Guidelines for physical activity in children with heart disease

ABSTRACT

Justification:

In recent years, there has been increasing recognition of children with heart disease in our country. These children belong to different age groups and have untreated, partially treated, or completely treated heart disease. The role of physical activity for optimal physical, emotional, and psychosocial well-being for children is well understood. There is a challenge for the parents and the medical professionals to take a decision regarding the type of physical activity safe for the child as heart disease may affect the hemodynamic demands. Most of the existing international guidelines focus on competitive sports in operated heart disease children. This may be of limited use when we have a mixed population of children with heart disease, different types of sports in our country and where a larger subset is looking for recommendations to leisure time activities.

Process:

The Pediatric Cardiac Society of India decided to formulate recommendations for physical activity in children with heart diseases. A committee of experts, who were well-versed with the subject of physical activity in children with heart disease, volunteered to take up the task of writing the guidelines. The recommendations emerged following deliberations of the committee members, on the virtual platform as well as mails. The final version of manuscript was approved by all committee members and all members are co-authors of this manuscript. The different types of physical activities were defined including leisure sports and competitive sports. The exercise was classified based on the mechanical action of muscles involved into dynamic and static components. Each type of exercise was then classified based on the intensity into low, medium, and high. Recommendations for the type of physical activity for individual heart lesions were decided based on the rationale available.

Objectives:

The recommendations here are made with an intention to provide general guidelines for physical activity in children with operated and unoperated heart diseases, not excluding a need for individualizing a plan, serial assessment, and comprehensive checkup in special situations.

Recommendations:

We hope the recommendations mentioned below would provide basic clarity in planning physical activity in children with heart disease. This is with the hope to encourage physically active life, at the same time ensuring a safety net.

INTRODUCTION

Congenital heart defects (CHDs) are the most common birth defects, the birth prevalence being 8-12 per 1000 live births.[1] The overall survival rates and life expectancy have dramatically improved across the world due to the advances in pediatric cardiology and cardiac surgery. In regions with good access to screening, early diagnosis, and treatment, over 90% of patients born with CHD survive to adult life with good long-term outcome, although majority require ongoing surveillance.[2] In middle and low-income countries, lack of advanced level of care for children with CHD results in mixed CHD population, consisting of those with native, un-intervened CHD, and those where a complete or partial intervention has been done. These children/adults; with CHD have increased cardiovascular risks due to their intrinsic structural defect, ventricular dysfunction, pulmonary hypertension, or rhythm abnormalities. The question that commonly bothers the medical fraternity and the parents is how to decide which type of physical activity can be safely recommended to these patients and to what extent.

Justification for developing Indian guidelines

International guidelines on physical activity in CHD that mostly focus on patients who have been operated in the past, and on competitive sports, might not be useful in Indian settings, where the types of sports may also differ. These guidelines are summarized in Table 1.[3,4,5,6,7] Keeping in mind these challenges, the Pediatric Cardiac Society of India decided to formulate guidelines to help the medical team to decide safe physical activity on a regular basis for children and adolescents with congenital or acquired structural heart disease, either operated or unoperated. Since every child is different in terms of disease affliction with different structural defects, functional class, and underlying residual abnormalities, it necessitates different protocols for exercise. We hope that these guidelines would help individualize the advice related to any physical activity. The serial assessment might be required as the hemodynamic status could change over time for some children with structural heart disease.

Table 1.

Summary of guidelines published on physical activity in congenital heart disease

Year the article was published	Study performed by	Details related to the physical activity
		Type	Age group	Diseases included
2004 (Maron BJ et al.)	American Heart Association	Recreational sports	Young patients	Genetic cardiovascular diseases
2005 (Graham TP et al.)	American College of Cardiology (36th Bethesda conference)	Competitive athletes	Patients with cardiovascular abnormalities	Congenital heart diseases, acquired heart diseases, coronary artery disease, arrhythmias
2005 (Pelliccia A et al.)	European Society of Cardiology	Competitive sports participation	Young and adult age	Shunt lesions, stenotic lesions, cyanotic heart diseases, valvular heart diseases, ischemic heart disease, cardiomyopathies, arrhythmia
2012 (Takken T et al.)	Association for European Pediatric Cardiology	Physical activity, recreational sport, exercise training	Pediatric patients	Congenital heart disease (shunts, stenotic lesions, cyanotic diseases)
2015 (Van Hare GF et al.)	American Heart Association and American College of Cardiology	Competitive athletes	Patients with cardiovascular abnormalities	Congenital heart disease (shunts, stenotic lesions, cyanotic diseases)

Preamble

• 1. A complete diagnosis including the functional status of the patient must be made before applying these guidelines for advice regarding physical activity. The patient may be referred to a higher center if required

• 2. The proposed guidelines are meant to assist the health care provider (pediatrician, cardiologist, and pediatric cardiologist) for recommending physical activity/exercise for patients with CHD-operated or unoperated. While these may be applicable to the majority, each case needs an individualized approach, and exceptions may have to be made. Guidelines should not replace clinical judgment

• 3. These guidelines are made keeping in mind the current health care status in India. Subsequent modifications may be necessary in the future as pediatric cardiac care evolves

• 4. The recommendations are classified into three categories according to their strength of agreement.[8]

  • • Class I (Strong): Is recommended/is indicated and should be administered. Benefit >>> Risk
  • • Class IIa (Moderate): Is reasonable, can be useful/effective. Benefit >> Risk
  • • Class IIb (Weak): May be reasonable and may be considered. Effectiveness is not well established. Benefit ≥ Risk
  • • Class III No benefit (Moderate): Is not recommended. Should not be administered
  • • Class III Harm (Strong): Potentially harmful, should not be administered

Level (Quality) of evidence: 5 levels

• • Level A: High-quality evidence from more than one randomized controlled trial (RCT)

• • Level B-R (Randomized): Moderate quality evidence from 1 or more RCTs or meta-analysis

• • Level B-NR (Nonrandomized): Moderate quality evidence from well-designed non-RCT/observational/registry studies

• • Level C-LD (Limited data): Studies with limitations of designs or execution

• • Level C-EO (Expert opinion): Consensus of expert opinion based on clinical experience.

Aims and objectives

• 1. To decide the recommendation regarding the type/duration/frequency of exercise for individual CHDs and some acquired heart diseases seen in the pediatric population

• 2. To consider certain parameters such as ventricular function, dilatation, hypertrophy, pulmonary artery pressures, oxygen saturation, aortic dimensions, cardiac rhythm, history of syncope, prescribed medications while formulating these recommendations

• 3. To formulate specific guidelines for each CHD seen commonly in practice. Separate recommendations will be made for patients with native CHDs and for patients with operated CHDs (with or without residual defects).

Defining various types of physical activities

The terms “physical activity” and “exercise” are often confused with each other. Physical activity is defined as any body movement executed by muscle contraction, leading to an additional energy consumption exceeding basal metabolic rate.[9] The level of physical activity can be variable. For example, vigorous activity is defined as activities that increase the metabolic rate to more than six time the resting rate, i.e., more than 6 metabolic equivalents of task (MET) whereas moderate activity is defined as an activity within 3-6 MET. Physical activity is a broader understanding of all types of physical movements, and it positively correlates with physical fitness. Exercise is a subset of physical activity that is planned, structured, repetitive with an objective of improving or maintaining physical fitness.[9]

Other terms used are leisure sports and competitive sports. A leisure sport is a recreational physical activity without the pressure to play or continue to play or play at a higher intensity than is desired by the participant.[6] On the other hand, competitive sport is organized, competitive and skillful physical activity with fixed rules of commitment and pressure to train/play or continue to play at a high intensity regardless of whether that intensity is desired by the participant.[6] Exercise training is specialized, planned methods of physical activity to increase one’s physical activity capacity, performance, or fitness levels.[6]

Types of exercise

Physical activities can be characterized into two types based on the mechanical action of the muscles involved. (1) Dynamic component (isotonic) and (2) static component (isometric).[10] However, most sports involve both components. The dynamic exercise involves changes in muscle length and joint movement with rhythmic contractions that develop a relatively small intramuscular force. Static exercise, on the other hand, involves the development of a relatively larger intramuscular force with little/no change in muscle length or joint movement.[11]

The cardiovascular system responds acutely in different ways to both types of physical activities.[12,13] Dynamic exercise performed with a large muscle mass causes a marked increase in oxygen consumption. There is a substantial increase in cardiac output, heart rate, stroke volume, systolic blood pressure (BP), and a moderate increase in mean arterial pressure. This is accompanied by a decrease in diastolic pressure resulting in a marked decrease in total peripheral resistance. In contrast, static exercise causes a small increase in oxygen consumption, cardiac output and heart rate and no change in stroke volume. There is a marked increase in systolic, diastolic, and mean arterial pressure and no appreciable change in total peripheral resistance. Overall, dynamic exercise causes a volume load on the left ventricle (LV), whereas static exercise causes a pressure load. The acute response to both dynamic and static exercise includes factors that are important in determining myocardial oxygen demand. The chronic adaptation to repeated bouts of dynamic exercise causes a large absolute LV mass and chamber size, whereas static exercise causes a large LV mass with no increase in chamber size.[12,13]

In addition to static-dynamic classification, some physical activities might be associated with high risk of injury if loss of consciousness occurs, and some have a high possibility of body collision or trauma that could have serious consequences (like bleeding or aortic dissection).[6]

Classification of sports and exercise

Each type of exercise, whether dynamic or static is further classified by the level of its intensity into low, medium, and high. The increasing dynamic component is defined in terms of the estimated percent of maximal oxygen uptake achieved (VO2), whereas the increasing static component is related to the estimated percent of maximal voluntary contraction. As most of the activities involve both components, it can be classified into nine types, with different intensities of dynamic and static components, as shown in Table 2[5,11] (modified for Indian sports).

Table 2.

Adapted and modified from Mitchell et al

	Low dynamic (I) <40% VO2	Moderate dynamic (II) 40%-70% VO2	High dynamic (III) >70% VO2
Low static (A) <20% MVC	Cricket Golf Riflery Billiards	Table tennis Tennis (doubles) Volleyball	Running (marathon) Badminton
Moderate static (B) 20%-50% MVC	Gymnasticsc Archery Auto racingcs Motorcyclingcs Sailing Divingcs Equestriancs	Kho-Kho Kabaddic Field events (Jumping) Figure skatingc Running (sprint) Synchronized swimmings	Basketballc Running (mid/long) Swimming Tennis (single) Field hockeyc
High static (C) >50% MVC	Field events (throwing) Martial artsc Rockclimbingcs Weightliftingc	Body buildingc Wrestlingc	Boxingc Cyclingcs Rowing Speed-skatingcs

^cDanger of bodily collision, ^sIncreased risk of syncope. MVC: Maximal voluntary contraction, VO₂: Maximal oxygen uptake

I (A) would cause the lowest total cardiovascular demand and III (C) the highest. I (B), I (C), II (A), II (B), II (C), III (A), and III (B) would cause moderate cardiovascular demand.

High-intensity interval training (HIIT) is described as high-intensity exercise with aerobic intervals, with the target intensity existing in submaximal VO₂ max between 85% and 95% of the peak heart rate. Sprint interval training (SIT) involves low-volume supramaximal (i.e., all-out) performance. These exercise protocols require a shorter exercise duration to obtain the same benefit as that provided by moderate-intensity exercises.[14] HIIT has shown a relatively low rate of major adverse cardiovascular events for patients with coronary artery disease or heart failure when applied within cardiac rehabilitation (CR) settings.[15] However, prescription of HIIT is complex since there are an unlimited number of possible exercise/recovery interval combinations, which should be adapted to the individual patient. SIT has been adopted only in healthy, sedentary, and usually young people and should not be adopted in individuals with underlying cardiovascular disease as the potential risk has not been evaluated in this population.[14]

Advantages of physical activity in patients with congenital heart defects

Data from high-income countries suggest that obesity is common in children with CHD and acquired heart disease and may pose additional cardiovascular risk.[16] Obesity might be due to a sedentary lifestyle because of restrictions imposed by parents or physicians or due to inadequate communication by the practitioner. This indirectly could be rooted in the fear and anxiety of living with a chronic disease and the possibility of having sudden cardiovascular death due to exercise. In addition, these children are at risk to experience depression, anxiety, behavioral disorders, and low self-esteem which may persist into adulthood.

There is overwhelming evidence that exercise is safe in most patients with structural heart disease. Studies have shown that most of the sudden cardiovascular deaths happening in adult patients with CHD occur at rest.[17] There is evidence that exercise training within adult cardiac rehabilitation (CR) promotes cardiorespiratory fitness, strength, flexibility, and metabolic health; reduces morbidity, mortality, and hospital admissions; and improves the quality of life.[18] Emerging research with pediatric populations with cardiac conditions similarly suggests that exercise training can have beneficial effects, although there is some variability in effects.[19,20] In addition to numerous physiological and functional benefits, exercise is associated with enhanced self-esteem, confidence, initiative, and perception of skill improvement.[21] It improves overall health and is an important recognized tool for preventing chronic diseases later in life. Hence, the benefits are multifocal, not only limited to physiological improvement, but also to psychological, cognitive, and social well-being. These benefits would improve the long-term cardiovascular health of children with heart disease.

Assessment of physical activity

While deciding about the exercise recommendation in children with CHD, two questions need to be answered – one is the ability of the patient to perform the physical activity and second is the safety of the child for that physical activity, based on the understanding of the impact of that physical activity on the heart.

Conventionally, assessment of physical activity is done by asking questions to the child or parents, like “how long can you walk/how many flights of stairs can you climb?” We understand that in this manner we may not accurately understand their functional capacity. There also could be a discrepancy between what the patient is perceiving compared to what the parents are perceiving about the child’s physical capacity. For an objective analysis, the following tests are recommended. In general, dynamic exercise is preferred for testing as it can elicit maximal cardiovascular response, compared to static exercise where fatigue might limit further exercise.

1. 6-minute walk test (6MWT): It measures the distance a patient can quickly walk on a flat surface in a period of 6 minutes (6MWD).[22] The course is a straight path 30 m in length and turn each time he reaches the end of the course. As most activities of daily living are performed at submaximal levels of exertion, the 6MWD may better reflect the functional exercise level for daily physical activities. No exercise equipment or advanced training for technicians is required. Baseline pulse oximetry (baseline heart rate and oxygen saturation) and dyspnea – fatigue level (Borg scale) is measured. Heart rhythm and ECG are not monitored here. Post-walk pulse oximetry and Borg Scale is recorded. The number of laps are recorded at the end of 6 minutes. 6MWT assesses the submaximal exercise capacity which is practically the functional exercise level for daily physical activities. Although 6MWD correlates well with peak oxygen consumption in highly symptomatic patients, its utility and validity in patients with only mild-to-moderate impairments are dubious.[23] The 6MWT is a useful measure of functional capacity targeted at patients with at least moderately severe impairment. In a population-based study aiming to provide normative data for the 6MWT in healthy children between 11 and 14 years, the mean distance walked in 6 minutes was observed to be 576 ± 93 m in boys and 545 ± 92 m in girls, respectively.[24]. The information obtained here is considered complementary to the cardiopulmonary exercise test.

2. Stress test: The child’s physiological response to exercise is measured by stress test and then interpreted against established standards. The stress test is used to assess exercise tolerance, to evaluate the safety of exercise for a child with CHD, and to elicit abnormalities that are not evident at rest. The normal stress test is done with BP, heart rate and ECG monitoring, and pulse oximeter using exercise protocols (Modified Bruce protocol[25]) that increase with intervals, commonly with a treadmill. Exercise capacity is reported in metabolic equivalents (METs) of exercise. In stress test, a good exercise capacity is more than 10 METs. Exercise is terminated mainly when the heart rate reaches a percentage of predicted maximum heart rate and/or when the child has symptoms. The major limitations of stress test include the subjective nature of the self-reported symptoms by the child and baseline rhythm abnormalities such as sinus node dysfunction where monitoring of the heart rate may be unreliable. Children with pulmonary hypertension, cardiomyopathy with heart failure/arrhythmia, severe outflow obstruction, prolonged QTc, severe aortic dilatation are at high risk for stress test, which should be avoided.

3. Cardiopulmonary exercise testing (CPET) can provide all the parameters such as maximal oxygen consumption, maximal heart rate (MHR), and first ventilatory anaerobic threshold. However, CPET is an expensive equipment and not easily available. Fortunately, the rate of perceived exertion (RPE) or Borg scale correlates well with the blood lactate levels and oxygen consumption.[26] The fixed percentage of MHR correlates well with RPE of the Borg Scale[27] [Table 3]. Hence, monitoring of both the heart rate and RPE can be used.[28]

Table 3.

The relation between the rate of perceived exertion and % of maximal heart rate

RPE/Borg scale	Subjective description of exercise intensity	Feels like	Percentage of MHR
<10	Very light	Nothing	<35
10-11	Light	Something	35-54
12-13	Moderate	Perspiring	55-69
14-16	Hard	Sweating working	70-89
17-19	Very hard	Hard working	≥90
20	Maximal	Cannot breathe anymore	100

RPE: Rate of perceived exertion, MHR: Maximal heart rate

Based on Tables 2 and 3, the dynamic activity which is considered to be relative intensity is classified into low, moderate, and high as follows[29] [Table 4]. The relative intensity can be measured based on the stress test parameters.

Table 4.

Assessment of dynamic activity based on the stress test parameters

Relative intensity	Low (%)	Moderate (%)	High (%)
VO2 (%)	<40	40-70	>70
Borg scale	11-12	13-14	15-17
Percentage of MHR (%)	<60	60-75	75-90

VO₂: Maximal oxygen uptake, MHR: Maximal heart rate

ATRIAL SEPTAL DEFECT

Rationale

There is no demonstrative data that children with hemodynamically insignificant atrial septal defect (ASD) require exercise limitations or that it is related to acknowledged episodes of sudden cardiac death (SCD).[30] Patients with significant ASDs have an impaired exercise capacity and their VO2 max is reduced until 60% of predicted values and decreases with age.[31] Patients with significant ASDs with associated pulmonary hypertension can have reduced exercise capacity or can develop arrhythmias, syncope, chest pain, or sudden death with exercise.[32,33] Patients with right-to-left shunt across the ASD can have increased hypoxemia on exercise with a very high risk of sudden death.[30,33]

Once the ASD is closed, the reduction of volume overload is associated with rapid RV remodeling (≅1 month after the procedure) and a significant exercise capacity improvement (≅6 months after the procedure).[34] The improvement in terms of exercise capacity after ASD closure occurs in patients of all ages, even elderly ones[34] but is more marked when the procedure occurs at an early stage during childhood.[35] No randomized trial has compared catheter and surgical ASD closures in terms of CPET parameters’ variation. The existence of an impaired exercise capacity after ASD closure may be associated with RV dysfunction and/or abnormal vascular pulmonary response to exercise.[36]

Recommendations

(A) Untreated atrial septal defect

• 1. Small and moderate ASD: Should be allowed to participate in all sports (Class I; Level of Evidence C-EO)

• 2. Large ASD: (i) With no PAH: Should be allowed to participate in all sports (Class I; Level of Evidence C-EO)

• (ii). With PAH, arrhythmias, and mitral regurgitation: Should be allowed low intensity sports (Class I; Level of Evidence C-EO), restriction for competitive sports in case of symptomatic atrial or ventricular arrhythmias, and for high-intensity sports in case of pulmonary arterial hypertension (PAH) arterial systolic pressure >40 mmHg)

• 3. ASD with right-to-left shunt: Should be allowed only low dynamic sport leisure activities and be forbidden competitive sports (Class III; Level of Evidence C-EO).

(B) ASD closed by surgical repair or catheter intervention:

• 1. Closed in childhood with no right heart dilatation and no PAH: Should be allowed to participate in all sports 3-6 months after the procedure (Class I; Level of evidence B-NR), after device closure lighter physical activity can be resumed in 10-14 days once the puncture site in the groin is healed and contact sports to be avoided till 6 months (Class I; Level of evidence C-EO)

• 2. Closed in adulthood (after 40 years of age): Should be allowed at least low-intensity sports (Class I; Level of evidence B-NR)

• 3. With residual PAH, arrhythmias, and ventricular dysfunction: Should be allowed low-intensity sports, restriction for high-intensity sports (Class I; Level of evidence B-NR).

VENTRICULAR SEPTAL DEFECT

Rationale

When children with hemodynamically insignificant ventricular septal defects (VSDs) or surgically closed VSDs have undergone exercise testing, results have generally showed normal exercise capacity despite a mild chronotropic limitation in the latter group.[30,37,38] This is seen with the practice of surgical closure of significant VSDs in the first 2 years of life as this avoids or minimizes the cardiopulmonary abnormalities produced by myocardial dysfunction or progressive pulmonary vascular disease.[39] Pulmonary arterial hypertension significantly affect exercise capacity and thus, quality of life.[40] Moreover, strenuous or extreme isometric efforts can be dangerous and should be discouraged in pulmonary artery hypertension with any congenital heart disease patients.[41] Patients with Eisenmenger physiology, apart from exhibiting a markedly impaired exercise capacity, have the risk of sudden death.[40]

Recommendations

(A) Untreated ventricular septal defect

• 1. Small VSD and moderate VSD with normal pulmonary artery pressures: Should be allowed to participate in all sports (Class I; Level of Evidence B-NR)

• 2. Moderate VSD with mild-to-moderate pulmonary hypertension: Low-intensity sports recommended, and competitive sports are contraindicated (Class III, Level of evidence C-EO)

• 3. Large VSD with severe hyperkinetic PAH and left-to-right shunt: Not applicable as would be a candidate for repair

• 4. Large VSD with right-to-left shunt: Should be allowed only low dynamic sport leisure activities and should be forbidden competitive sports (Class III; Level of Evidence C-EO).

(B) Ventricular septal defects closed by surgical repair or catheter intervention

• 1. With no/small residual defect, no pulmonary artery hypertension, no arrhythmias, no myocardial dysfunction: After 3-6 months should be allowed to participate in all sports (Class I; Level of Evidence B-NR), after device closure lighter physical activity can be resumed in 10-14 days once the puncture site in the groin is healed and contact sports to be avoided till 6 months (Class I; Level of evidence C-EO)

• 2. With arrhythmias, mild-to-moderate pulmonary hypertension or myocardial dysfunction: Low-intensity sports recommended, and competitive sports are contraindicated (Class III, Level of evidence C-EO)

• 3. With severe pulmonary artery hypertension: Should be allowed only low dynamic sport leisure activities and should be forbidden competitive sports (Class III; Level of Evidence C-EO).

PATENT DUCTUS ARTERIOSUS/AORTOPULMONARY WINDOW

Rationale

There is no demonstrative data that children with hemodynamically insignificant patent ductus arteriosus (PDA) require exercise limitations or that it is related to the acknowledged episodes of SCD.[30] Pulmonary arterial hypertension with PDA significantly affect exercise capacity and thus quality of life.[40] Moreover, strenuous or extreme isometric efforts can be dangerous and should be discouraged in pulmonary artery hypertension with PDA.[41] Patients with Eisenmenger physiology and PDA, apart from exhibiting a markedly impaired exercise capacity, have risk of sudden death.[40]

Recommendations

(A) Untreated patent ductus arteriosus

• 1. Small PDA and moderate PDA with normal pulmonary artery pressures: Should be allowed to participate in all sports (Class I; Level of Evidence B-NR)

• 2. Moderate PDA with mild-to-moderate pulmonary hypertension: Low-intensity sports recommended and competitive sports are contraindicated (Class III, Level of evidence C-EO)

• 3. Large PDA with severe hyperkinetic PAH and left-to-right shunt: Not applicable as would be a candidate for repair

• 4. Large PDA with right-to-left shunt: Should be allowed only low dynamic sport leisure activities and should be forbidden competitive sports (Class III; Level of Evidence C-EO).

(B) Patent ductus arteriosus closed by surgical repair or catheter intervention

• 1. With no/small residual defect, no pulmonary artery hypertension, no arrhythmias, no myocardial dysfunction: After 3-6 months should be allowed to participate in all sports (Class I; Level of Evidence B-NR)

• 2. With mild to moderate pulmonary hypertension or myocardial dysfunction: Low intensity sports recommended, and competitive sports are contraindicated (Class III, Level of evidence C-EO)

• 3. With severe pulmonary artery hypertension: Should be allowed only low dynamic sport leisure activities; competitive sports must be forbidden.(Class III; Level of Evidence C-EO).

AORTIC STENOSIS

Rationale

A significant proportion of seemingly asymptomatic patients with aortic stenosis (AS) have an abnormal response to exercise, associated with a higher increase in mean pressure gradient, with a limited LV contractile reserve (latent LV dysfunction).[42] With exercise, pulmonary artery pressure may rise further, presumably due to left ventricular diastolic dysfunction, and exercise pulmonary hypertension has been found to be associated with a high risk of cardiac events.[43] Sudden death is more likely to occur in patients with severe LV hypertrophy, exertional syncope, chest pain, dyspnea, or LV strain pattern on the ECG.

Exercise capacity following the treatment of AS is dependent on how close to normal the residual valve function is, and to what degree a preoperative impaired myocardial function and/or an increased pulmonary vascular resistance is normalized, which may take up to 12 months’ time.[44] Following aortic valvuloplasty during early infancy, the exercise capacity is, in general, remarkably well preserved.[45] In a subset of patients without symptoms, however, there may be profoundly depressed peak oxygen uptake, related primarily to an inability to augment forward stroke volume to appropriate levels at peak exercise.[45] After treatment, patients may be left with residual valve gradient, aortic insufficiency, or both, and may experience recurrence or progression, and thus, continued clinical follow-up is needed.[7]

Recommendations

(A) Untreated aortic stenosis

• 1. Mild (a mean Doppler gradient of <25 mm Hg, normal ECG, normal exercise tolerance, no symptoms): Can participate in all competitive sports but should undergo serial evaluations of AS severity on at least an annual basis (Class I; level of evidence C-EO).

• 2. Moderate (mean Doppler gradient of 25-40 mm Hg, mild or no LV hypertrophy, no LV dysfunction, absence of LV strain pattern on ECG, no symptoms): Selected athletes with moderate AS may participate in low static or low and moderate dynamic competitive sports, if exercise testing to at least the level of the sports activity demonstrates satisfactory exercise capacity without symptoms, ST-segment depression, or ventricular tachyarrhythmias, and with normal BP response (Class IIa, level of evidence C-EO). Follow-up is recommended every 6 months.

• 3. Moderate (mean Doppler gradient of 25-40 mm Hg, symptomatic, LV dysfunction at rest or under stress): Should not engage in any competitive sports and may only consider participation in low-intensity leisure sport activity depending on symptoms and exercise testing results (Class III, level of evidence C-EO)

• 4. Severe (mean Doppler gradient of >40 mm Hg with or without symptoms like exercise intolerance, chest pain, near syncope/syncope, LV hypertrophy with strain on ECG, and abnormal BP response to exercise): Should not engage in any competitive sports and may only consider participation in low-intensity leisure sport, depending on symptoms and exercise testing results (Class III, level of evidence C-EO).

(B) Aortic stenosis after balloon dilation or surgery

• 1. Athletes with residual AS may be considered for participation in sports, after 3 months, according to the above recommendations based on severity (Class IIb; Level of Evidence C-EO). Furthermore, those with prosthetic or bioprosthetic valves who are receiving anticoagulant treatment should not participate in sports with a risk of bodily collision

• 2. Athletes with aortic valve regurgitation (AR) after AS surgery may be allowed to participate in sports depending on the degree of valve insufficiency. Children with mild or moderate aortic regurgitation need not be withheld from any kind of physical activity in the absence of LV dilatation, aortic dilatation/aneurysm, or arrhythmia (Class I, level of evidence C-EO). Those with severe AR and significant LV diastolic enlargement as well as those with mild or moderate AR and symptoms (regardless of LV dimension) should not participate in any competitive sports (Class III, Level of evidence C-EO).

The recommendations for those having bicuspid aortic valve with dilated aorta are being described under the head of aortopathy.

MITRAL STENOSIS

Rationale

Most patients with significant mitral stenosis (MS) will be sufficiently symptomatic during exercise that the question regarding participation in competitive sports will not arise, but patients with mild-to-moderate MS may be asymptomatic even with strenuous exercise. MS results in increased left atrial (LA) pressure, leading to pulmonary hypertension.[5] With exercise (with an increase in heart rate and cardiac output), there can be a sharp increase in the gradient across the mitral valve, leading to sudden marked increase in pulmonary capillary and pulmonary artery pressures, at times resulting in sudden acute pulmonary edema.[46]

In patients who have undergone valvuloplasty, significant increases in peak exercise oxygen uptake and cardiac output have been observed on exercise testing after 6 months.[47]

Recommendations

(A) Untreated mitral stenosis

• 1. Mild stenosis (mitral valve area >1.5 cm², mean gradient ≤7 mm Hg, rest pulmonary artery systolic pressure <35 mm Hg and exercise pulmonary artery wedge pressure less than or equal to 20 mm Hg), sinus rhythm: Can participate in all competitive sports, except for high dynamic and high static (Class IIa; Level of Evidence C-EO). Follow-up annually to determine whether sports participation can continue (Class I; Level of Evidence C-EO)

• Exercise testing to at least the level of activity achieved in competition and the training regimen is useful in confirming asymptomatic status in patients with MS (Class I; Level of Evidence C-LD).

• 2. Moderate stenosis (mitral valve area >1.5 cm², mean gradient between 8 and 15mm Hg, rest pulmonary artery systolic pressure less than or equal to 50 mm Hg), sinus rhythm: May participate in low and moderate static and low and moderate dynamic competitive sports if exercise testing has shown normal tolerance to the level of activity (Class IIb; Level of Evidence C-EO). Follow-up yearly.

• (Mild and moderate MS is considered under the progressive MS category).

• 3. Severe stenosis (mitral valve area <1.5 cm², mean gradient >15 mm Hg, rest pulmonary systolic pressure >50 mm Hg, and exercise pulmonary artery wedge pressure >25 mm Hg), atrial fibrillation (AF) or sinus rhythm: should not participate in competitive sports, except for low-intensity sports (Class III; Level of Evidence C-EO)

• 4. Patients with MS of any severity who are in atrial fibrillation or have a history of atrial fibrillation, and who must receive anticoagulation therapy, should not engage in any competitive sports involving the risk of bodily contact (Class III; Level of Evidence C-EO).

(B) MS after percutaneous valvuloplasty or surgery:

• Athletes with residual MS may be considered for participation in sports 6 months post-intervention, according to the above recommendations based on severity (Class IIb; Level of Evidence C-EO), provided there is no pulmonary hypertension and no significant regurgitation. Furthermore, those who are receiving anticoagulant treatment should not participate in sports with a risk of bodily collision.

PULMONARY STENOSIS

Rationale

In pulmonary stenosis (PS), right ventricle (RV) systolic pressure and oxygen demand are increased at rest[48] and exercise capacity is decreased with significantly higher resting heart rate and lower peak oxygen uptake.[48] Diminished exercise tolerance in children with moderate-to-severe PS indicates impaired ability to sustain adequate cardiac output.[6]

Medium and long-term follow-up studies have shown favorable results with either surgical or balloon valvuloplasty in terms of freedom from reintervention, cardiac function, and exercise capacity.[6] Following balloon valvuloplasty, in the long term, pulmonary regurgitation (PR) and consequent RV dilation are related to impaired exercise cardiopulmonary function.[49] Cardiac performance may remain abnormal in adults after relief of stenosis likely due to myocardial fibrosis causing slow and reduced improvement of right ventricular hypertrophy.[50]

Recommendations

(A) Untreated pulmonary stenosis

• 1. Mild PS (Doppler peak gradient across the obstruction <36 mm Hg or peak velocity <3 m/s),[51] normal RV function: Can participate in all competitive sports (Class I; Level of Evidence B-NR). Annual re-evaluation is recommended

• 2. Moderate PS (Doppler peak gradient 36-64 mmHg or peak velocity 3-4 m/s), normal RV, normal ECG, or only mild RV hypertrophy: can consider participation only in low and moderate dynamic and low static sport (Class IIb; Level of Evidence B-NR). Follow-up every 6 months.

• 3. Severe PS (Doppler peak gradient is >64 mmHg or peak velocity >4 m/s), variable degree of RV hypertrophy: May participate only in low-intensity leisure physical activity based on symptoms and individual assessment (Class IIb, level of evidence B-NR). Should not engage in any competitive sports (Class III, level of evidence C-EO). Eligibility to competitive sports can be granted only after successful repair, either by balloon valvuloplasty or surgical valvotomy.

(B) Pulmonary stenosis after percutaneous valvuloplasty or surgery

• 1. Mild PS, 6 months postinterventional/postsurgical, only mild PR, normal RV function (ejection fraction >50%), normal ECG or only mild RV hypertrophy, no significant arrhythmias: Can participate in all competitive sports (Class I, level of evidence C-EO). Yearly follow-up is necessary

• 2. Moderate PS, 6 months postinterventional/postsurgical, mild to moderate PR, normal RV, normal ECG, or only mild RV hypertrophy can participate in low and moderate dynamic and low static sport (Class IIb; Level of Evidence B-NR). Follow-up every 6 months

• 3. Severe PS, 6 months posttreatment, usually with RV hypertrophy: Should restrict their physical activity to low intensity, preferably dynamic sport, based on symptoms and individual assessment (Class IIb, level of evidence C-EO). Should not engage in any competitive sports (Class III, level of evidence C-EO)

• 4. Severe pulmonary insufficiency with no significant RV volume overload enlargement, no arrhythmias: If asymptomatic and with normal RV systolic function on serial examinations and exercise testing: May participate in all sports, except high-intensity competitive sports, (Class IIb; Level of Evidence C-EO). If severe pulmonary insufficiency with marked RV enlargement or RV function abnormal: May participate in low-intensity competitive sports only, following a complete clinical examination with ECG, echocardiogram, ambulatory ECG monitor, and exercise test (Class III; Level of Evidence C-EO).

COARCTATON OF AORTA

Rationale

Coarctation of the aorta (CoA) imposes significant afterload on the LV, resulting in compensatory left ventricular hypertrophy, LV dysfunction, and the development of arterial collaterals.[51] Exercise capacity is reduced in patients of CoA before intervention and even after a good result of intervention with no residual stenosis.[40,52]

Many patients after coarctation repair are normotensive at rest but might develop a disproportionate rise in systolic BP during exercise.[52,53] Even after successful treatment, persistent arterial hypertension at rest or during exercise is an important risk factor for premature coronary artery disease, ventricular dysfunction, and rupture of aortic or cerebral aneurysms.[51]

Recommendations

(A) Untreated coarctation of aorta

• 1. Mild coarctation, defined as resting systolic BP gradient <20 mm Hg between the upper and lower limbs, a peak systolic BP not exceeding the 95^th percentile of predicted with exercise, no significant ascending aortic dilation, no cerebral aneurysm with a normal exercise test: Can participate in all competitive sports, except those with a very high static component (Class IIa, level of evidence C-EO). Exercise testing to evaluate for exercise-induced hypertension may be reasonable in older children and adults with CoA who can exercise (Class IIb, Level of evidence C-LD)

• 2. Hemodynamically significant coarctation, defined as a systolic BP arm/leg gradient >20 mm Hg or exercise-induced hypertension (a peak systolic BP exceeding the 95^th percentile of predicted with exercise) or with significant ascending aortic dilation (z score >3.0): Sports of only low intensity static and dynamic component may be allowed (Class IIb; Level of Evidence C-EO).

(B) Treated by surgery or balloon angioplasty or stent

• 1. During the first postoperative year, athletes should refrain from high-intensity static exercise and sports that pose the danger of bodily collision (Class IIb; Level of Evidence C-EO)

• 2. Athletes who are >3 months past surgical repair or stent placement with <20 mm Hg arm/leg BP gradient at rest, normal BP at rest and exercise, as well as (1) a normal exercise test with no significant dilation of the ascending aorta (z score <3.0), (2) no aneurysm at the site of coarctation intervention, and (3) no significant concomitant aortic valve disease: May be considered for participation in competitive sports, but with the exception of high-intensity static exercise, as well as sports that pose a danger of bodily collision (Class IIb; Level of Evidence C-EO). Yearly follow-up is recommended, with complete reassessment every second year

• 3. Athletes with evidence of significant aortic dilation or aneurysm formation (not yet at a size to need surgical repair) may be considered for participation only in low-intensity dynamic and static sports (Class IIb; Level of Evidence C-EO)

• 4. Systolic hypertension on exercise test in children operated upon for coarctation of the aorta: May participate only in leisure physical activity of low to moderate intensity. High-intensity static sports and competitive sports are to be avoided (Class IIb; Level of Evidence C-EO).

TETRALOGY OF FALLOT

Rationale

Cyanotic congenital heart disease is associated with exercise intolerance and patients are unlikely to engage in competitive sports because of their own self-limiting activity.[4] CPET shows significant desaturation with exercise, with performance and symptoms related to underlying anatomy, including in those with palliative shunts.[4,7]

In patients with repaired TOF, some of the anatomic abnormalities and complications encountered are residual right ventricular outflow tract (RVOT) stenosis, branch pulmonary (PA) stenosis, significant pulmonary regurgitation (PR) (following a transannular patch repair), tricuspid regurgitation (TR), RV dilation and dysfunction, residual VSD with consequent LV volume overload, aortic root dilation with AR, LV dysfunction, atrial/ventricular tachycardia (VT), and SCD.[51,54]

The following are the reported risk factors for SCD: Right and/or left ventricular dysfunction, extensive ventricular fibrosis (on CMR), QRS ≥180 ms, significant PR, nonsustained ventricular tachycardia (VT) on Holter monitoring, inducible VT at EP testing, long-lasting palliative shunts, and older age at the time of repair.[51] Exercise performance of young patients operated on for tetralogy of Fallot is marked by lower maximal heart rate (MHR) and systolic blood pressure (BP) values,[55] an abnormal ventilatory response[6] and a significantly reduced peak workload, irrespective of the surgical approach.[55] Patients with late repair frequently develop greater degrees of RV hypertrophy with reduced compliance of the RV, leading to diastolic RV dysfunction after complete repair.[6]

Recommendations

(A) Untreated Tetralogy of Fallot

Clinically stable, no symptoms of heart failure and arterial saturation above approximately 80%: May be considered for participation in only low-intensity sports (Class IIb; Level of Evidence C-EO). Prior to competitive participation in low-intensity sports, a complete evaluation, including exercise testing, is recommended (Class I; Level of Evidence C-EO).

(B) Palliated

Arterial saturation above approximately 80%, absence of tachyarrhythmias, ventricular dysfunction or symptoms of impaired consciousness: Can participate in low-intensity sports (Class IIb; Level of Evidence C-EO).

(C) Post-repair

• 1. Asymptomatic, no, or only mild RVOT obstruction, no more than mild PR, a normal or near normal biventricular function (EF >50%), and no evidence of arrhythmia on ambulatory ECG monitoring or exercise testing: May be considered for participation in moderate to high-intensity sports (Class I, level of evidence C-EO). Before participation in competitive sports, complete evaluation, including clinical assessment, ECG, imaging assessment of ventricular function, and exercise testing is recommended (Class I; Level of Evidence B-NR). Yearly follow-up with complete reassessment every second year is recommended.

• 2. Asymptomatic, moderate residual lesion with RV pressure <50% of systemic pressure, or residual VSD or moderate PR, but normal biventricular function, no arrhythmias on ambulatory ECG monitoring or exercise test: May participate in low and moderate static and dynamic sport (Class IIb; Level of Evidence B-NR). Sports eligibility should be re-assessed every 6 months by a thorough cardiovascular evaluation.

• 3. Marked PR and right ventricular volume overload, residual right ventricular hypertension (peak systolic RV pressure greater than or equal to 50% systemic pressure), significant residual intracardiac shunt not amenable to correction: May participate in low-intensity competitive sports only, following a complete clinical examination with ECG, echocardiogram, ambulatory ECG monitor and exercise test (Class IIb; Level of Evidence C-EO).

• 4. High-risk patients for clinical arrhythmia or SCD, patients with advanced biventricular dysfunction (EF <40%), severe outflow tract obstruction, or patients with marked ascending aortopathy: Should be restricted from all competitive sports, except for low-intensity static and dynamic leisure activity (Class III; Level of Evidence B-NR).

D-TRANSPOSITION OF GREAT ARTERIES

Rationale

Exercise capacity after repair of d-transposition of great arteries depends on the initial pathology and type of surgery performed. After a Mustard or a Senning atrial switch procedure, most patients have diminished exercise capacity with diminished peak oxygen consumption.[51,56] They may be at higher risk of sudden death with a high proportion of sudden death events occur during exertion. The strongest predictors of sudden death are the presence of significant atrial or ventricular arrhythmias and severe systemic ventricular dysfunction, although prior VSD, age at repair, QRS duration, and heart failure symptoms may also be associated with an increased risk.[57,58]

After an arterial switch operation, exercise performance in children and adolescents, as assessed by cardiopulmonary exercise test in various studies, show subnormal to preserved maximal oxygen consumption and peak heart rate.[59,60] Significant RV outflow tract obstruction and abnormal pulmonary flow distribution (due to branch PA stenosis) and reduced LV stroke volume have been evaluated as independent risk factors for reduced peak VO2.[6,61] Patients with symptoms like syncope or exertional chest pain are at risk of sudden death due to reduced coronary flow.[7,62]

Adult patients with complex transposition who had a Rastelli-type repair can be entirely asymptomatic with a normal exercise capacity; however, residual abnormalities, relating to the conduit, or arrhythmias may occur.

Recommendations

• (A) Uncorrected (survivors of uncorrected d-transposition of great arteries, associated with VSD and PS): Please refer to recommendations for Tetralogy of Fallot.

• (B) Post atrial switch (Mustard or Senning)

• 1. Asymptomatic, no history of atrial flutter, supraventricular tachycardia, or ventricular tachyarrhythmia, no history of syncope, no ventricular dysfunction, normal exercise test, no exercise-induced ischemia: May participate in low and moderate static or low dynamic competitive sports, after a detailed clinical assessment (Class IIb; Level of Evidence C-EO).

• 2. Symptomatic, history of arrhythmias, suboptimal hemodynamics: Individualized recommendations for physical activity should be made, based on clinical stability (Class IIb; Level of Evidence C-EO).

• 3. Severe clinical systemic RV dysfunction, or recurrent or uncontrolled atrial or ventricular arrhythmias: Should be restricted from all competitive sports, except for low-intensity leisure physical activity (Class III; Level of Evidence C-EO).

• (C) Postarterial switch operation

• 1. Asymptomatic, normal ventricular function, normal exercise test, and no atrial or ventricular tachyarrhythmias: Can participate in low and moderate-intensity sports and all leisure sports activities. Participation in high-intensity competitive sports may be individualized based on detailed clinical assessment including ECG, imaging for ventricular function, Holter monitoring, and exercise testing (Class IIb; Level of Evidence C-EO). Yearly follow-up is recommended.

• 2. More than mild hemodynamic abnormalities (left or right ventricular dysfunction, ventricular hypertrophy, or dilation; RV outflow tract stenosis with the gradient of >30 mm Hg; more than mild neo-aortic insufficiency), no signs of ischemia or arrhythmia on exercise ECG: Can participate in low and moderate static or low dynamic competitive sports, after detailed clinical assessment, provided that the exercise test is normal (Class IIb; Level of Evidence C-EO). Sports eligibility should be re-assessed every 6 months.

• 3. Evidence of coronary ischemia: should be restricted from all competitive sports, except for low-intensity leisure physical activity (Class III; Level of Evidence B-NR).

EBSTEIN’S ANOMALY OF THE TRICUSPID VALVE

Rationale

Hemodynamic status in Ebstein’s anomaly depends on the severity of the tricuspid valve dysfunction, the degree of atrialization of RV, contractility of the remaining functional and systemic ventricle, type and severity of concomitant anomalies, and arrhythmias.[51] An atrial level shunt is present in over one-third of hearts, with subsequent potential right–left shunting.[6] Accessory pathways are frequent[51] and even mild cases may be associated with important arrhythmias.[4] Severe cases can be associated with physical disability and increased risk for sudden death with exercise.[4]

Patients with Ebstein anomaly have been noted to have an abnormal heart rate response to exercise, likely due to sinus node dysfunction, both pre- and postoperatively.[63] In nonoperated patients, exercise capacity deteriorates over time due to progressive decline in the ability to augment the forward stroke volume and heart rate during exercise.[64,65] The anatomical and functional severity of Ebstein anomaly, specifically the atrialized RV volume, has been found to be related to reduced exercise capacity.[66] Even after surgery, only a small minority of postoperative patients have been found to have a normal exercise capacity.[63]

Recommendations

(A) Unrepaired Ebstein’s anomaly of the tricuspid valve

• 1. Mild: Asymptomatic, no cyanosis, normal RV size, no more than mild tricuspid regurgitation, normal LV systolic function, no evidence of atrial or ventricular tachyarrhythmias on 24-hour ECG monitoring: Can participate in all sports (Class IIb; Level of Evidence C-EO)

• 2. Moderate: Asymptomatic, moderate tricuspid regurgitation, normal arterial saturation, no evidence of arrhythmia on 24-hour ECG monitoring other than isolated premature contractions: Can participate in low-level dynamic and low to moderate-level static physical activities, and only low-intensity competitive sports (Class IIb; Level of Evidence C-EO)

• 3. Severe tricuspid regurgitation significantly dilated right atrium and RV, right atrial pressure >20 mmHg, LV systolic dysfunction, symptoms during exercise or at rest, chronic atrial arrhythmias (atrial fibrillation) or repetitive ventricular arrhythmias: should be precluded from undertaking physical exercise of any level (Class III; Level of Evidence C-EO).

(B) Post-repair

• 1. No residual anomalies (absent or mild tricuspid regurgitation, no substantial increase in cardiac chamber size), asymptomatic, no atrial or ventricular tachyarrhythmias on ambulatory ECG monitoring and exercise test: Low-intensity static and low dynamic competitive sports may be permitted 3 months after surgical repair (Class IIb; Level of Evidence C-EO). Selected athletes with an excellent hemodynamic result after repair may be permitted additional participation on an individual basis after 3 months from repair.

• 2. Residual abnormalities (more than mild TR, ventricular dysfunction, shunting, arrhythmias, or other complications): Should be precluded from sports participation in proportion to the severity of their problems (Class III; Level of Evidence C-EO).

CONGENITALLY CORRECTED TRANSPOSITION OF THE GREAT ARTERIES

Rationale

The clinical course and exercise tolerance of patients with congenitally corrected transposition of great arteries (ccTGA) often depend on the presence and severity of associated cardiac anomalies, such as VSD, PS, and systemic AV valve abnormalities.[4,54] The anatomically abnormal systemic atrioventricular valve is at risk of progressive TR, with consecutive systemic RV dysfunction and heart failure, which is an independent predictor of exercise intolerance and death in ccTGA.[6,7,54] These patients are also at increasing risk for the development of supraventricular tachycardia and spontaneous complete heart block with age.[4,6]

A few studies on isolated ccTGA have shown markedly diminished peak oxygen consumption.[67,68] Chronotropic incompetence and impaired stroke volume response of the systemic RV are thought to be the prevalent causes.[6] RV dysfunction has been found to be associated with increased RV filling pressure on tissue Doppler imaging,[6,68] with reduced coronary flow reserve on positron emission tomography, and with myocardial fibrosis on cardiac MRI.[6]

Limited data are available to assess the risks associated with sports participation in those who have had a double-switch procedure resulting in the redirection of pulmonary venous blood to the LV and aorta.[7] Individualized assessment including evaluation of the venous baffle and Rastelli or arterial switch integrity is required before consideration of sports participation.[7]

Recommendations

(A) Unrepaired ccTGA

• 1. Isolated ccTGA, asymptomatic, no systemic ventricle enlargement or dysfunction, no evidence of atrial or ventricular tachyarrhythmia on ambulatory ECG monitoring or exercise testing, no exercise-induced ischemia: May be eligible for participation in low to moderate static and low dynamic sports (Class IIb; Level of Evidence C-EO). Sports with a large static component are not recommended.

• Periodic re-evaluation is important to detect the development of arrhythmias and deterioration of systemic RV function or systemic AV valve regurgitation and should include clinical assessment, ECG, imaging assessment of ventricular function, Holter monitor, and exercise testing (Class I; Level of Evidence B-NR).

• 2. Severe clinical systemic RV dysfunction, severe RV outflow tract obstruction, or recurrent or uncontrolled atrial or ventricular arrhythmias: Should be restricted from all competitive sports, except for low-intensity leisure sports (Class III; Level of Evidence C-EO).

• (B)Postrepair (VSD closure, tricuspid valve replacement, sub pulmonary LV to PA conduit or double-switch surgeries): Recommendation for physical activity should be individualized depending on the clinical status.

TRUNCUS ARTERIOSUS

Rationale

Truncus arteriosus is usually repaired in early childhood, and the surgical repair may involve VSD closure, RV to Pulmonary artery (PA) conduit placement, and replacement of the truncal (neoaortic) valve.[54] In the older patient with unrepaired truncus arteriosus, Eisenmenger physiology is typical.[54] Recommendations regarding physical activity in truncus arteriosus can be inferred from the recommendations for the specific components, such as VSD or aortic valve disease. In this section, recommendations regarding RV to PA conduit or Eisenmenger syndrome in unrepaired truncus arteriosus have been discussed.

Studies on early and mid-term follow-up after surgical repair for truncus arteriosus have shown acceptable results. Cases with right ventricle to pulmonary artery conduit may present with symptoms of exertional dyspnea, palpitations, and syncope on follow-up[51] and complications such as truncal valve regurgitation, truncal valve stenosis, conduit obstruction, reoperations for truncal valve or conduit replacement, ascending aortic dilation, or residual pulmonary hypertension may be seen.[51,69]

Patients who have pulmonary vascular disease may develop cyanosis at rest and intense cyanosis with exercise[7] or syncope due to right heart failure with reduced cardiac output[6] and are at risk for sudden death during sports activity.[7]

Recommendations

(A) Repaired using right ventricle-PA conduit, no residual pulmonary hypertension

• 1. Asymptomatic, no, or mild conduit obstruction: May participate in all sports (Class I; Level of evidence C-EO). Regular follow-up is recommended every year and must include an assessment of exercise capacity, RV systolic pressure (conduit gradient), RV function, and arrhythmias

• 2. Symptomatic, high RV pressure due to conduit obstruction: Must generally limit themselves to low-intensity physical activity, although individualized recommendations for physical activity should be made, based on symptoms and clinical assessment (Class IIb; Level of Evidence C-EO).

(B) With pulmonary hypertension

• 1. Pulmonary artery peak systolic pressure ≤30 mm Hg or mean pulmonary artery pressure of <25 mm Hg: Can participate in all competitive sports (Class I; Level of Evidence B-NR)

• 2. Moderate or severe pulmonary hypertension, with a mean pulmonary artery pressure >25 mm Hg: Should be restricted from all competitive sports, except for low-intensity dynamic or low static physical activity, provided the arterial oxygen saturation remains above 80%, tachyarrhythmia with symptoms of impaired consciousness is not present and ventricular function is not or only mildly impaired (Class III; Level of Evidence B-NR).

SINGLE VENTRICLE LESIONS

Rationale

Hemodynamic status in children with single ventricle lesions depends on many variables such as type, contractility of the functional systemic ventricle, severity of AV valve regurgitation, presence of cyanosis, obstructions in systemic outflow, and underlying arrhythmias. Patients who have undergone palliation with Fontan operation are known to have significantly reduced exercise performance which is multifactorial.[7]

Recommendations

• 1. Patients with single ventricles who have not undergone palliative surgeries are advised against any kind of sports participation.(Class IIa, Level of evidence B-NR), needs to be individualized

• 2. It is advised that a thorough assessment be done for all patients with Fontan operation prior to sports participation for evaluating risk factors associated with sudden death. A comprehensive evaluation should include cardiac imaging, ECG, and CPET.(Class I; Level of evidence B)

• 3. After Fontan operation, if there is significant exercise intolerance during a maximal effort test, as evidenced by an inability to increase BP or heart rate, systemic desaturation, or development of arrhythmias, restriction from participation in moderate and high-intensity sports should be considered.(Class III; Level of Evidence C-EO)

• 4. Athletes who have undergone the Fontan procedure and who have no symptomatic heart failure or significantly abnormal intravascular hemodynamics and no arrhythmias can participate only in low-intensity class IA sports (Class I; Level of Evidence C-EO).

• 5. All Fontan patients requiring chronic anticoagulation should be restricted from participation in contact sports.

CONGENITAL ANOMALY OF THE CORONARY ARTERY

Rationale

Congenital coronary artery anomalies include the anomalous aortic origin of a coronary artery (AAOCA), anomalous left coronary artery arising from the pulmonary artery (ALCAPA), coronary myocardial bridges, and coronary artery fistulas. Of these, the most frequent is the anomalous origin of the left coronary or the left anterior descending artery from the right coronary sinus of the aorta.[70] AAOCA is the second most common cause of SCD in children and adolescents, after hypertrophic cardiomyopathy (HCM).[71] High-risk features include intramural course, interarterial course, slit-like ostium, or acute angulation.[71]. A ‘scissor-like’ physiologic effect has been proposed in case of an interarterial AAOCA course, in which coronary artery compression between the great vessels occurs during times of high cardiac output, like exercise, leading to myocardial ischemia,[72] lethal ventricular arrhythmia or SCD. Anomalous aortic origin of the left coronary artery carries a significantly greater risk of SCD, notably with high intensity, competitive sports.

In case of ALCAPA, despite normalization of global left ventricular function after surgical intervention, limitations associated with the myocardial blood flow or chronic myocardial injury can persist for years after surgery,[73] as evidenced by myocardial scarring on MRI.[74] Even in the absence of scar tissue, regional left ventricular function may be reduced in the long term, after repair.[75] Malignant ventricular arrhythmias can develop from an old infarct-related scar tissue or as a result of an acute ischemic event during exercise.[76]

A normal 12-lead electrocardiography does not exclude the anomalous origin of a coronary artery and the exercise test may also be negative.[70] Transthoracic echocardiography is a better tool to identify the origin and course of the proximal coronary arteries. Further tests may include coronary computed tomography angiography, magnetic resonance angiography, or cardiac stress testing using stress echocardiography or stress myocardial perfusion imaging, among others. Several surgical procedures are available including coronary unroofing, coronary artery reimplantation, ostial plasty, pulmonary artery translocation and rarely, coronary artery bypass grafting.

Recommendations

(A) Uncorrected coronary artery anomalies

• 1. Athletes with an anomalous origin of a right coronary artery from the left sinus of Valsalva (AAORCA) should be evaluated by an exercise stress test. For the asymptomatic person with a negative exercise stress test, permission to compete can be considered after adequate counseling of the family as to risk and benefit, with appropriate clinical follow-up (Class IIa; Level of Evidence C-EO).

• 2. Nonoperated athletes with AAORCA who exhibit symptoms, arrhythmias, or signs of ischemia on exercise stress test should be restricted from participation in all competitive sports, except for class IA sports, before a surgical repair (Class III; Level of Evidence C-EO).

• 3. Athletes with an anomalous origin of a left coronary artery from the right sinus of Valsalva, especially when the artery passes between the pulmonary artery and aorta, should be restricted from participation in all competitive sports, except for class IA sports, before surgical repair.(Class III; Level of Evidence B-NR).

(C) Post-repair

• 1. Following surgical correction, athletes should be restricted from competitive sports for 3 months. Prior to clearing patients from competitive exercise restriction, a stress test should be performed in patients without a history of ischemic chest pain or aborted sudden cardiac death (SCD) to rule out ischemia. Athletes may return to competitive exercise training if no inducible ischemia is present after maximal exercise stress testing and there are no ischemic symptoms present.

• 2. Patients with aborted SCD should only return to competitive exercise at least 12 months after surgery, and only if they remain free of ischemic symptoms and if exercise stress testing does not show evidence of ischemia or high-risk arrhythmias.

• 3. After repair of anomalous origin of a coronary artery from the pulmonary artery, decisions regarding exercise restriction may be based on presence of sequelae such as myocardial infarction or ventricular dysfunction (Class IIb; Level of Evidence C).

HYPERTROPHIC CARDIOMYOPATHY

Rationale

Myofibrillar disarray, ventricular hypertrophy, microvascular ischemia, and fibrosis predispose patients with hypertrophic cardiomyopathy (HCM) to re-entrant ventricular arrhythmias. Triggering arrhythmias and sudden deaths in short term and inappropriate long term maladaptive effects on the heart are the major concerns for exercise in HCM patients. Initial guidelines recommend restricting competitive sports participation for individuals with HCM to low-static/low-dynamic sports such as golf or bowling, and vigorous recreational exercise has also been recommended against.[77]

HCM patients with high risk for SCD need to be identified prior to exercise planning, which can be challenging. Clinical guidelines recommend that all patients should undergo SCD risk stratification at their initial evaluation and periodically thereafter prior to sports prescription. The ESC risk score uses seven variables (age, syncope, family history of SCD from HCM, maximal LV wall thickness, left atrial diameter, LV outflow obstruction, and non sustained ventricular tachycardia (NSVT)) to assess the risk of SCD of patients with HCM.[78] It is however not validated for children <16 years. Children with any of the following risk factors such as a family history of sudden death, prior exercise-associated syncope or arrhythmia, abnormal blood pressure (BP) response on exercise testing (defined as either the failure to increase by at least 20 mmHg or a drop of at least 20 mmHg during effort), ejection fraction <55%, and New York Heart Association class IV are considered high risk and recommended to refrain from all kinds of exercises.[78]

It should be however noted that the absence of risk factors does not convey immunity to SCD. Thus, adopting an individualized approach with risk stratification is necessary. Patients with HCM wishing to pursue a competitive sport are advised to start with a low intensity sport followed by gradual exercise training over a period of 4-6 months with a close watch on symptoms such as pre syncope. This has shown to result in improvements in peak oxygen consumption. Goal will be to achieve an appropriately safe level of exercise intensity that will not increase arrhythmia risk or exacerbate symptoms. Sports involving burst exertion which causes abrupt rise in heart rate should be avoided for example, sprinting as compared to swimming.

Recommendations

• 1. Patients with any of the following conditions as below should be considered as absolute contraindication for sports (Class II B/Level C LD).[79]

• (1) History of aborted SCD; (2) Symptoms, particularly unheralded syncope (3) Exercise-induced VT (4) High ESC 5-year risk score (5) Significant increase in LV outflow gradient (>50 mmHg) (6) Abnormal BP response to exercise.

• 2. Athletes with low-risk profile, asymptomatic, mild clinical expressions, LVOT gradients <30 mmHg, low ESC risk score, normal exercise testing may be considered to participate in all competitive sports and recreational sports, apart from contact sports. Such athletes should be reviewed annually to assess the changes in symptoms and risk profile.(Class II B/Level C LD).[79]

• 3. Prior to engaging in sports, it is advisable to evaluate the HCM athlete by ambulatory ECG (monitoring period should include a exercise session if possible), Cardiac MRI to measure extent of myocardial fibrosis by late gadolinium enhancement (LGE) (involving >15% of LV myocardium, suggestive of high risk for SCD and VT), exercise testing (or CPET) for peak VO2 and detecting abnormal BP response to exercise (defined as <20 mmHg increase in SBP from baseline, or exercise-induced hypotension) (Class II A/Level C EO).

DILATED CARDIOMYOPATHY

Rationale

The clinical course of dilated cardiomyopathy (DCM) is variable, and it is difficult to predict to what extent the dysfunctional ventricle can perform to accommodate the need for an increase in cardiac output during exercise. Evaluation under the following headings is necessary prior to exercise prescription: (i) Degree of LV dilatation and dysfunction, (ii) Hemodynamic response to exercise, (iii) Presence of exercise-induced arrhythmias, and (iv) Peak VO2 values on exercise.

Assessment during exercise with failure to increase LVEF at peak exercise by more than 10% and low CPET values can provide clues in asymptomatic individuals whose LV may not withstand high-intensity sports. As a rule, symptomatic individuals with DCM should abstain from most competitive sports associated with moderate or high exercise intensity.

Athletes with an unequivocal diagnosis of DCM but only mildly reduced LV systolic function (ejection fraction [EF] ≥45%50%) may be considered low risk for an adverse event if they are asymptomatic, without prior history of unexplained syncope, and without frequent/complex ventricular tachyarrhythmias on ambulatory ECG monitoring and exercise stress testing.[79]

However, individuals with Laminin A/C or filamin C mutations are associated with an increased risk of life-threatening arrhythmias. There is emerging evidence that exercise may have an adverse effect on cardiac function and risk for potentially fatal arrhythmias in this subset.[79]

DCM patients who are symptomatic, or have LVEF <45%, or extensive LGE (i.e., >20%) on cardiac MRI, and/or frequent ventricular tachyarrhythmias on ambulatory ECG monitoring and exercise stress testing, or unexplained syncope, are all grouped under high risk for intensive sports and should be advised to limit their exercise to leisure-time activities.

The clinical outcome of left ventricular noncompaction (LVNC) is determined by the presence of symptoms, severity of LV dysfunction, and the nature of the ventricular arrhythmias (VAs).[79] There are no reported adverse cardiac events in the absence of LV dysfunction regardless of the severity of LV trabeculation.[79] The recommendations for LVNC are the same as DCM.

Recommendations

• 1. Those who are asymptomatic with mild LV systolic dysfunction (LVEF >45%-50%) with no history of arrhythmia (normal ambulatory 24 h Holter), no previously identified high-risk genetic mutations (Laminin A/C), no LGE on MRI and no family history of cardiomyopathy or sudden death may indulge in competitive sports of all levels only after thorough evaluation for risk.(Class IIb/Level C LD)

• 2. Children with a diagnosis of DCM with any of the following: LVEF <45%, extensive LGE on CMR (>20%), symptomatic, with a history of syncope and frequent ventricular arrhythmia complexes on Holter or exercise testing should not indulge in competitive sports but can participate in leisure activities (Class III/Level C LD).

MYOCARDITIS

Rationale

Myocarditis is defined as an inflammatory process of the myocardium, with histological evidence of myocyte degeneration and necrosis of nonischemic origin, associated with inflammatory infiltration.

It has been a consensus that those with a clinical diagnosis of myocarditis should be temporarily excluded from competitive and amateur leisure-time sports activity to promote the resolution of the inflammatory process. This recommendation is independent of age, gender, and extent of LV dysfunction.

Following the resolution of the clinical picture (at least 6 months after the onset of the disease), clinical reassessment (imaging studies, exercise stress test, and Holter monitor) is indicated prior to resuming competitive sports.[80] However, there is no specific test that can establish a complete resolution of the inflammatory process in myocarditis. Depressed LV function, presence of LGE, and complex VAs during exercise or Holter monitoring are the recognized risk markers for adverse outcomes.[79] Patients in whom the findings of acute inflammation have resolved may still harbor the risk for arrhythmias related to the resultant myocardial scar. LV dysfunction and tachyarrhythmias are the major prognostic determinants of adverse events.[81]

Recommendations

1. Athletes diagnosed with myocarditis should be restricted from exercise for 6 months to promote resolution of inflammation, depending on the clinical severity and duration of the illness and LV function, and extent of inflammation.(Class II B/Level C)

2. It may be reasonable to allow participation in competitive sports of moderate-intensity following 6 months since myocarditis if the LV function has normalized, and absence of arrhythmias on 24-hour Holter (Class IIA/Level C).

III. ACQUIRED VALVULAR HEART DISEASE

Eligibility for competitive sports participation in patients with valvular heart disease is dependent on severity of valve disease, functional capacity, symptomatic status, myocardial status (ventricular dilatation and function), and risk of arrhythmia. Aortic and mitral stenosis has already been discussed and the guidelines will remain the same whether it is congenital or acquired.

AORTIC REGURGITATION

Rationale

Aortic regurgitation (AR) can occur due to a congenitally abnormal valve (bicuspid), loss of coaptation due to aortic root enlargement, or degeneration following infective process (rheumatic/infective endocarditis). Chronic AR causes dilatation and hypertrophy of LV due to volume overload. It may be difficult to assess a dilated LV in an athlete as an increase in size can occur either due to endurance activity or due to AR. Although AR hemodynamics may improve with exercise because of shortened diastole and reduced peripheral vascular resistance, in some cases, coronary perfusion may be compromised because of increased wall stress, LV hypertrophy, and reduced diastolic BP.[46] Exercise testing is important to identify symptomatic status and guidelines are based on exercise tolerance during exercise testing in these individuals. Exercise testing to at least the level of activity achieved in competition and the training regimen is helpful in confirming asymptomatic status and assessing BP responses.[46]

Recommendations

• 1. Athletes with mild to moderate AR, with normal LV dimensions and function and normal exercise testing can participate in all competitive sports (Class I, Level of evidence C-LD)

• 2. Athletes with mild-to-moderate AR, with LV dilatation (>35 mm/m²) can still participate in all competitive sports if there is no progression of LV dimensions, LVEF >50% and exercise testing parameters are normal (Class I, Level of evidence C-LD)

• 3. Individuals with more than moderate AR can participate in competitive sports only if LVEF >50%, nondilated LV (LVEDD <35 mm/m²)[79] and normal exercise tolerance on exercise testing (Class IIB Level of evidence C-EO)

• 4. In patients with severe AR, participation is reasonable in low static and low dynamic sports only if LVEF >50%, with mild LV dilation, no progression of LV dilatation, and normal exercise testing (Class IIb Level of evidence C-EO)

• 5. Patients with severe AR and any of the following: LV ejection fraction <50%, LVESD >25 mm/m², abnormal exercise testing should not participate in any competitive sport. (Class IIB, Level of evidence C-EO).

MITRAL REGURGITATION

Rationale

Exercise recommendation in athletes having mitral regurgitation is dependent on the severity of mitral regurgitation (MR), extent of LV dilatation, LV systolic function, and presence or absence of pulmonary hypertension. Static exercise that results in an increase in BP or heart rate can result in increased regurgitant volume and pulmonary capillary pressures and may be potentially deleterious.[46]

The recommendations are selective for patients having primary MR due to causes such as rheumatic heart disease, infective endocarditis, connective tissue disorder including the more common etiology of mitral valve prolapse. MR due to secondary causes such as coronary disease and HCM are not included.

Special consideration and workup are necessary for athletes with mitral valve prolapse syndrome. This subset is known for progression of MR, infective endocarditis, and supraventricular arrhythmias and rarely SCD. T-wave inversions and ventricular arrhythmias arising from LV are known high-risk factors for sudden death in athletes with MVP.[82] They should further be evaluated with exercise testing and 24-hour ECG and should be advised for cardiac MRI (CMRI) if either of the above risk factors are present.

Recommendation

• 1. Asymptomatic athlete with mild to moderate MR with normal LV size (LVEDD <35 mm/m² in men or <40 mm/m² in women), no arrhythmias and preserved LV function (LVEF >60%) with systolic PAP <50 mmHg can participate in all competitive sports⁷⁹ (Class I; Level of Evidence C EO).

• 2. Athletes with severe MR can participate in low-intensity sports only if the results of exercise testing are normal, normal LV systolic function at rest (LVEF >60%), LV size is normal to mildly enlarged with systolic PA pressures <50 mmHg and there are no ventricular arrhythmia or ventricular premature beats on 24-hour Holter.(Class IIB; Level of Evidence LD).

• 3. Asymptomatic athletes with MVP with mild to moderate MR and absence of risk factors can participate in all competitive sports.[79] However, in the presence of risk factors, competitive sports should be avoided, and only low-intensity aerobic exercises should be encouraged to improve functional capacity.

• 4. Patients in atrial fibrillation or a history of atrial fibrillation who are receiving long-term anticoagulation should not participate in sports involving risk for bodily collision.

AORTOPATHY

Rationale

Aortopathies in children are broadly grouped into those associated with CHD and those with inherited thoracic aortopathies. Inherited aortopathies are further divided into syndromic heritable thoracic aortic disease (sHTAD) which include Marfan syndrome, Turner syndrome, Loeys-Dietz syndrome, vascular Ehlers-Danlos syndrome, and Shprintzen-Goldberg syndrome. Nonsyndromic thoracic aortic disease (nsHTAD) describes a familial form of aortopathy without any systemic features with mutations in genes encoding members of TGFb signaling pathway; extracellular matrix, FBN1; COL3A1 or smooth muscle cells, including actin (ACTA2), myosin (MYH11), myosin light chain kinase (MYLK) [83,84]. Aortic dilatation associated with the bicuspid aortic valve results from an interplay between altered transvalvular hemodynamics and intrinsic aortopathy.

Intense exercise induces acute elevations in systolic BP and stroke volume in dynamic sports (isotonic) and substantial rise in systemic vascular resistance in isometric exercise. This exerts shear stress on the weakened aortic wall leading to rapid dilatation and acute catastrophic aortic dissections. Approximately 1-5% of sudden death in young athletes is caused by acute aortic dissections.[85] On the other hand, recent studies have also demonstrated that mild-to-moderate dynamic exercise have a positive effect on aortic wall structure and compliance.[86]

Recommendations

• 1. Assessment of the aorta using advanced imaging modality CMR/CT and exercise testing with BP monitoring is recommended in all patients with aortopathies before exercise and sports recommendations.(Class I, Level of Evidence C EO)

• 2. Patients with bicuspid aortic valve with normal-sized aortic root and ascending aorta (z score <2) can be allowed to participate in all competitive sports. It is important that function of the bicuspid valve, whether stenotic or regurgitant, be established in determining participation.(Class I; Level of evidence C LD)

• 3. Those with bicuspid aortic valve with aortic dimensions above the normal range z scores: 2-3.5, participation in low static and moderate dynamic competitive sports with a low likelihood of significant bodily contact may be considered. For these athletes, avoidance of intense weight training should be considered (Class IIb, Level of Evidence C LD)

• 4. Athletes with bicuspid aortic valve and severely dilated aorta z scores >3.5 should not participate in any competitive sports (Class 1 Level of evidence C EO)

• 5. Patients with Marfan’s syndrome and those with nonsyndromic aortopathies (proven genetic mutations) may be allowed to participate in low dynamic and up to moderate static if they do not have one or more of the following risk factors: (Class IIa Level of evidence C LD)

  • i. Aortic root or ascending aorta z score >2
  • ii. Moderate-to-severe mitral regurgitation
  • iii. Left ventricular systolic dysfunction (ejection fraction <40%)
  • iv. Family history of aortic dissection

• 5. Patients with Marfan’s syndrome and nonsyndromic aortopathies should not participate in any competitive, bodily contact or high resistant sports if the aorta or ascending aorta dimensions z score >2 (Class I Level of evidence B)

• 6. It is reasonable to allow those diagnosed with Ehlers Danlos and Loeys Dietz in low dynamic and low static sports only if following risk factors are absent: (Class II, Level of evidence C EO)

  • i. Aortic enlargement (score >2) or dissection, or branch vessel enlargement
  • ii. Moderate to severe mitral regurgitation
  • iii. Extracardiac organ system involvement that makes participation hazardous.

KAWASAKI DISEASE

Rationale

Kawasaki disease is an acute vasculitis of childhood leading to coronary artery aneurysms in 25% of untreated patients.[87] It is known that despite resolution of aneurysms, coronaries in Kawasaki patients can have abnormal responses to vasodilators like nitroglycerin and can have lower myocardial perfusion reserve compared with controls.[88,89] Studies have demonstrated that exercise capacity of these patients is normal regardless of the extent of coronary artery involvement.[88,89,90] Exercise prescriptions in these patients is tailored based upon inducible myocardial ischemia, arrhythmias, and bleeding associated with thromboprophylaxis.[91]

Recommendations

• 1. Participation in competitive sports or high-intensity activities should be guided by results from testing for inducible myocardial ischemia or exercise-induced arrhythmias in patients with coronary aneurysms/dilatations.(Class IIa; Level of Evidence C-LD)

• 2. Patients with no coronary aneurysms or transient aneurysms and with no exercise-induced ischemia or arrhythmias may be considered for participation in all sports starting 8 weeks after the illness has resolved (Class IIb; Level of Evidence C-LD). Risk reassessment is recommended at 3-to 5-year intervals or according to the current guidelines (Class IIb; Level of Evidence C-LD)

• 3. For patients taking dual-antiplatelet or anticoagulation therapy, activities involving a risk of bodily contact, trauma, or injury should be restricted or modified.

CONCLUSION

This paper provides the recommendations for physical activity in children with congenital heart disease, operated and unoperated. Many of the recommendations are based on expert opinion, which may change as more scientific evidence emerges in the future. For now, we hope that this paper would offer reassurance to parents and the practitioners to encourage patients to have a physically active life and would also help providing an individualized prescription. The routine follow-up visits can be used as an opportunity by the practitioners with the help of a nutritionist/psychologist to counsel the parents and the child about the maintenance of healthy safe lifestyle. We acknowledge the need for further studies with ideal research methodology to have high level of evidence and stronger recommendations and long-term follow-up to assess the effect of such advice.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.