Home-based cardiac rehabilitation: development, implementation and outcome evaluation in patients with coronary artery diseases in Lahore, Pakistan – a mixed-methods study protocol

Abstract

Introduction

Cardiac rehabilitation (CR) is an important strategy to bring cardiac patients back to a normal life after a cardiac event. The benefits of CR as part of secondary prevention are widely known among people who have undergone myocardial infarction or revascularisation. As evidenced by several systematic reviews and meta-analyses, home-based CR (HBCR) has similar or greater effects on health-related quality of life, health outcomes, physical activity, anxiety and unplanned visits to the emergency department as compared with centre-based CR. The purpose of this study is to develop a contextual HBCR intervention and evaluate its effects on quality of life, health behaviours, bio-physiological parameters and emergency hospital visits of patients with coronary artery diseases in Lahore, Pakistan.

Methods and analysis

This study will employ a mixed-method exploratory sequential research design. The researchers will invite 15–20 cardiac patients and 12–15 healthcare providers for semi-structured interviews in the qualitative phase of the study. Once the intervention is developed and validated through the qualitative phase, the outcomes will be evaluated through a single-blinded randomised control trial in the quantitative phase. A total of 118 patients with acute coronary syndrome will be recruited through a screening checklist and randomly allocated into the control and intervention groups (59 patients in each group). The inductive coding approach will be used for the thematic analysis of qualitative data, whereas the quantitative data will be analysed through descriptive and inferential statistics using SPSS to see the difference within the groups, between groups and between three intervals.

Ethics and dissemination

The Ethical Review Committee of Aga Khan University and Mayo Hospital Lahore under the registration number 2023-8282-24191 and No/75749MH have approved this study protocol, respectively. The results of this study will be disseminated to participating patients (in the Urdu language), healthcare professionals and the public by publishing the manuscript in an open-access peer-reviewed journal and presenting it at different conferences.

Trial registration number

Australian New Zealand Clinical Trial Registry (ACTRN12623000049673p).

STRENGTHS AND LIMITATIONS OF THIS STUDY.

• A strength of this study is that it employs a mixed-methods research design to explore the needs of Pakistani patients and develop a contextual home-based cardiac rehabilitation (CR).

• Another strength of this study is that healthcare providers before implementation will validate the interventions developed through a qualitative approach.

• Another strength is that the implementation will be done through a single-blinded randomised control trial to minimise selection and assessment bias.

• The main weakness of this study is that the comparison could not be done with the centre-based CR due to the lack of CR facilities available in the country.

• Another weakness is that one study setting has been selected for data collection.

Introduction

Pakistan is facing a dual burden of disease (communicable and non-communicable). Among all the non-communicable diseases, premature mortality due to cardiovascular diseases (CVDs) is reported to be 29% and it possesses a major cause of mortality worldwide.¹ In the year 2020, 240 720 people died of coronary heart disease in Pakistan 2020, which makes up around 16.5% of all mortalities. With a rate of 193.56 mortalities per 100 000 population, Pakistan ranked 30th in the world.² There is an increase in the prevalence of CVDs-related deaths in low-income and middle-income countries whereas prevalence has declined in high-income countries. Very little attention has been given to preventing the risk factors of CVDs at both the primary and secondary levels in South Asia, particularly in Pakistan.³

Despite this fact, the treatment modalities for CVDs are far more advanced now as compared with the past two decades. These modalities are available in many acute coronary care units and revascularisation centres in large cities in Pakistan. However, the incidents of cases are still on the rise. Based on statistics in Pakistan, at least 46 people die in an hour due to heart attacks in a country.⁴ It indicates that despite the advancements in treatment modalities for CVDs, we are unable to get the incidents down; there is still a need to ensure such efforts for secondary prevention.

If we analyse the reasons behind these increasing numbers of CVDs, we come to realise that it is difficult to have control over it until risk factors for CVDs are avoided. In Pakistan, people do not regularly exercise or do physical activity (41.5%), they smoke a cigarette or/and use tobacco (19.7%), eat an unhealthy high saturated fatty diet in routine (36.3%) and a majority of them are living a sedentary lifestyle.^{5 6}

A great number of those patients who have experienced the first cardiac event in their lives, even after the treatment do not change their behaviour toward modifiable risk factors due to this perception in society that their unhealthy behaviour has nothing to do with their health. The majority of patients perceive that; smoking is not a cause of cardiac disease (52.34%), dietary habits have no role (77.88%) and 89.78% of patients assume that physical inactivity has no role in the development of ischaemic heart disease.⁷ As a result, they experience subsequent cardiac events. According to the National Organisation for coronary heart disease (CHD), all CHD patients should be prompted to participate in a cardiac rehabilitation (CR) programme after discharge.⁸

To make their behaviours change, CR as part of secondary prevention is an utmost strategy for those who experienced a cardiac event or underwent any other cardiac procedure to get back to their activities of daily living. Therefore, CR is one of the best strategies to bring the increasing number of cases down.⁹ CR possesses strategies for secondary prevention that allow cardiac patient to rebuild their capacity and reduce the number of hospital visits. Only four centres are offering CR facilities for the entire CVD population in Pakistan and all of them to the best of the researcher’s knowledge are located in two major cities in Pakistan (Karachi and Lahore).

These centres are facing some challenges including physicians’ reluctance to refer some patients, and the lack of resources, capacity and funding.¹⁰ Both physicians and patients had reported poor uptake of centre-based CR (CBCR). Some physicians showed reluctance when referring patients, whereas, patients’ willingness and distance from their residence are also reported barriers of the patients.¹¹

CBCR and home-based CR (HBCR) has greater effects on the quality of life, morbidity and mortality, and risk factors in patients. There are no differences in the effects of both when compared concerning smoking, systolic blood pressure (BP), triglycerides, exercise capacity, cardiac events and mortality. Comparatively, adherence to HBCR was higher than that of the centre-based. The patients, who had more than 65 years of age, adhered to it better. They also found that patients with better family support had higher adherence to HBCR.^{12 13}

Exercise-based CR has positive effects on clinical outcomes of patients with myocardial infarction (MI) in the absence of obstructive coronary artery disease (CAD) (coronary artery stenosis <50%). It improves physical health, quality of life (154.93±4.6 vs 134.20±8.2), and 6 min walking distance, and reduces reduction in all-cause mortality with no reported complications during and after the intervention.¹⁴

CBCR and HBCR has similar effects on morbidity, mortality, modifiable risk factors for CVDs, health-related quality of life, cardiac events, exercise capacity, BP, total cholesterol and low-density lipoprotein (LDL) cholesterol. Similarly, HBCR alone has the potential to improve exercise capacity, total cholesterol, anxiety and depression. Furthermore, the HBCR intervention includes an exercise programme, smoking-cessation counselling, and education regarding risk factors, nutrition and the medication used.^{15 16}

This work is predicated on a few assumptions such as CAD is Pakistan’s top cause of mortality among CVDs. A significant population suffers from a second cardiovascular event as a result of inadequate CR services provision, limited institutions and low patient compliance as well.

Furthermore, the incorporation of theory into the development of CR as secondary prevention intervention is a unique strategy to lay down the foundation of intervention on the theoretical concepts. Therefore, the Betty Neuman System Model (NSM) has been planned to be a guide for this research, as systems comprise several lines of defence and stressors threatening the system best fit to the concept of CR.^{17 18} Furthermore, almost all of the studies found were randomised control trial (RCT) and mostly measured health-related quality of life whereas very little is known about the effects of HBCR on cardiac health behaviours, cardiac anxiety, bio-physiological parameters and emergency hospital visits. Similarly, no study has used a mixed-method study approach to develop a contextual HBCR.

Thus, the study aims to develop and implement a contextual HBCR as part of a secondary prevention programme, thus preventing further coronary events and reducing the overall burden of CAD-related morbidity by improving quality of life and health behaviours and reducing the number of emergency hospital visits.

Primary research questions

• How do the experiences of cardiac patients and healthcare professionals help design home-based cardiac rehabilitation interventions suitable for patients with CADs in Lahore, Pakistan?

• What is the effect of HBCR as compared with usual care on quality of life and health behaviours of patients with CADs in Lahore, Pakistan?

Secondary research question

• What is the effect of HBCR as compared with usual care on cardiac anxiety, bio-physiological parameters, and emergency hospital visits of patients with CADs in Lahore, Pakistan?

Primary objectives

• To explore the experiences of cardiac patients and healthcare professionals in helping to design home-based cardiac rehabilitation interventions suitable for patients with coronary artery diseases in Lahore, Pakistan.

• To evaluate the effect of HBCR as compared with usual care on the quality of life and health behaviors of patients with CADs in Lahore, Pakistan.

Secondary objective

• To evaluate the effect of HBCR as compared with usual care on cardiac anxiety, bio-physiological parameters, and frequency of emergency hospital visits of patients with CADs in Lahore, Pakistan.

Null hypotheses

• H₀₁: There is no difference in the quality of life, health behaviours, cardiac anxiety, and bio-physiological parameters of patients with CADs who have received usual care with and without HBCR.

• H₀₂: There is no difference in the frequency of emergency hospital visits of patients with CADs who have received usual care with and without HBCR.

Methods and analysis

Research design

This research will employ a mixed-methods (exploratory sequential) study design. This research design is rooted in the pragmatic paradigm. The pragmatic paradigm is built on the principle of employing the best methods to investigate real-world problems. It permits the use of multiple data sources to answer one research question. This premise of pragmatism offers its philosophical and methodological appropriateness for mixed methods research. In this method, both quantitative and qualitative data are collected and integrated.¹⁹

Study phases

This implementation research will be conducted in two phases using a mixed-method exploratory sequential design. In phase I, a quality descriptive exploratory design will be used to explore experiences, challenges and perceived solutions for CR.

The phase II will employ a single-blinded parallel group RCT. The protocol for this trial followed SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) guidelines (refer online supplemental file 1).

Research setting

In this study, the patients will be recruited from the Cardiology Department of Mayo Hospital Lahore, Pakistan. Mayo Hospital is a public sector tertiary care hospital. It is the oldest and largest hospital in Pakistan with a capacity of 2399 beds to date. It offers almost all diagnostic and therapeutic services including cardiac medicine and surgery and is located in the centre of Lahore. Due to its geographic location and wide range of health services, patients from different sociodemographics seek care for their health conditions. Mayo Hospital Lahore does not have CR services and patients treated for CAD receive usual care as routine practice. Therefore, this setting will be used to offer contextually developed HBCR to the intervention group and results will be compared with patients who receive usual care.

Selection criteria for the quantitative phase

Phase II: inclusion criteria

• Patients with age between 18 and 65 years.

• Male and female.

• Patients diagnosed with acute ST elevated MI (STEMI), non-ST elevated MI (NSTEMI) and/or unstable angina.

• Patients underwent first percutaneous coronary intervention (PCI) and/or managed medically.

• Patients with New York Heart Association (NYHA) classification for dyspnoea I and II.

• Patients residing within 50 km of the vicinity of the Mayo Hospital Lahore.

• Patients who can understand, read and speak Urdu.

Exclusion criteria

• Patients with left ventricular ejection fraction <50%.

• Patients with resting systolic BP>200 mm Hg or resting diastolic BP>110 mm Hg.

• Patients with signs and symptoms of postprocedure ischaemia.

• All those patients who have been prescribed restricted mobility due to comorbidities such as aortic stenosis and dysrhythmias.

• All those patients who have altered quality of life such as due to comorbidities end-stage renal disease, liver failure and respiratory failure.

HBCR: intervention group

Quality of HBCR training module

The contextual HBCR intervention module will be developed by interviewing the expert in each domain of CR. After development, the same experts before implementation will review the module. Furthermore, each clinician will sign each component of the HBCR intervention before compiling it in the form of a booklet.

Referrals for CR

To make the process of random allocation smooth, the researcher will work closely with the cardiology team to develop a plan of referral for CR evaluation. Referrals will be initiated for the admitted patients after the procedure. This would help the researcher to review the patients’ data for eligibility based on the selection criteria of the study.

Phases of HBCR

CR involves coordinated care of many professionals and services. There will be three phases of CR starting after the cardiac procedure until 1 year of discharge.

HBCR phase I

In this phase, a few hours after the procedure, patients’ capacity to mobilise, risk factors and education, and possible facilitation into the programme will be assessed. Furthermore, the researcher will initiate phase I by examining the cardiac risk factors for all eligible patients by blood pressure, heart rate, NYHA classification for dyspnoea and present symptoms. Along with that, the patient’s cognitive function, readiness for a lifestyle change and overall health needs will also be evaluated. The complete assessment will be done in approximately 1 hour during hospitalisation, in a private room of the hospital. A few hours after the event or procedure is a critical window in which patients often feel highly motivated to initiate lifestyle changes.

HBCR phase II

Phase II includes functional capacity, physical activity and exercise, risk-factor modification, tobacco/smoking cessation, nutritional guidance, psychological counselling and medication adherence. Before entering into this phase, a submaximal exercise test, the 6 min walk test (6MWT) will be used as qualifying as well as for initiating the exercise prescription. The minimum distance required to qualify will be 150 m for non-surgical patients.²⁰ The 6MWT will be performed at the first follow-up that is, within 7 days after the procedure in a hospital setting for patients with stable angina, post-PCI, and with following MI. On the same visit, each patient in the HBCR group will receive a hard copy of the booklet as a guide to physical activity and exercise, strategies for risk-factor modification, nutritional guidance and the importance of medication adherence. The booklet will be developed specifically for this study with the help of NHS Hospitals and Intermountain.org guidelines. An electronic/soft copy of the booklet (pdf) will also be shared on their WhatsApp number. A reminder through a text message will be given every week to ensure their compliance with the educational module.

Furthermore, they will receive accessible videos freely about the home exercises, which include; aerobics, breathing, muscle relaxation, standing resistance band and upper body seated resistance band exercises on their WhatsApp numbers. The videos regarding the home exercises are readily available at Intermountain.org. Additionally, a structured personal health journal will be developed and provided for documenting daily activities such as BP, heart rate, physical activity and dietary intake.

After subsequent assessment and enrolment into phase II, patients will be followed physically in the clinics on their scheduled appointment/follow-up, that is, at 7 days, 4 weeks, 8 weeks and 12 weeks postdischarge and will be compensated financially (travel fare) for these visits. The topics mentioned in the handbook will be covered in these sessions and they will be taught about self-monitoring the exercise with a targeted heart rate between 60% and 75% and Borg dyspnoea scale for perceived exertion, respectively. The aim is to achieve a minimum of 150 min of moderate activity level each week as determined by a targeted heart rate between 60% and 75% and a Borg dyspnoea scale for perceived exertion. The researcher for the individual patient will calculate the targeted heart rate.

For the risk-factor modification, patients will be motivated to avoid smoking and tobacco use, weight management, and diabetes control (if applicable). For nutritional guidance, patients will be counselled to avoid food that contains high saturated fat and cholesterol such as processed meat, fried food, baked food, sweets, etc. These counselling sessions of 45–50 min will be conducted on their scheduled appointment/follow-up at hospital private rooms that is, at 7 days, 4 weeks, 8 weeks and 12 weeks postdischarge. Furthermore, seven 5–10 min telephonic follow-up sessions will be conducted by researcher and a trained cardiac nurse within 12 weeks (weekly for the initial 3 weeks (2nd, 3rd and 4th weeks), and then biweekly (6th, 8th, 10th, 12th weeks) until the 12th week).

HBCR phase III

On completion of phase II CR after the 12th week, patients will be continuing the CR as phase III. Phase III will be the long-term maintenance programme that includes monthly phone calls for a total of seven 5–10 min telephonic follow-up sessions by the researcher and a trained cardiac nurse up to 6 months from the date of discharge (16th, 20th and 24th weeks). The patients will be encouraged to continue the personal health journal until 24 weeks of enrolment. In this phase, patients will be followed physically in the hospital as part of their routine visit to the hospital on the 15th, 19th and 23rd weeks. The goal of HBCR is to support patients to adopt a healthy lifestyle in the end by putting each part of the intervention into their daily lives such as physical activity, healthy diet, etc.

Usual care: control group

Patients in the control group will receive the usual care. The usual care for this study is defined as following the cardiac procedure, patients get discharged and called for first follow-up on 7 days after the procedure with subsequent follow-ups on every 15-day interval. There is no CR facility available in the study setting. The routine care will be administered by face-to-face consultation physically on their scheduled follow-ups by cardiologists and researchers in the clinics for 15–20 min. Patients will be followed up to 6 months from the date of discharge from the hospital. However, if patients in the control group receive any outsource rehabilitation from any other institution, they will be considered dropped out, and their data will not be analyzed.

Explanation for choosing usual care as a comparator

After a careful review of the literature, the majority of studies have reported ‘usual care’ as a comparator arm to CBCR or HBCR. Furthermore, CR facility is not widely available in majority of the hospitals as part of routine care in Pakistan. Similarly, HBCR is also not implemented in a country. Since this study will first in Pakistan to develop and implement a contextual HBCR, the results will inform its effectiveness compared with routine care in improving quality of life, health behaviours, cardiac anxiety, bio-physiological parameters and frequency of unplanned hospital visits among patients. Therefore, having very limited CBCR facilities and a focus on health outcomes, the research team decided to have usual care available in the study setting as a comparator arm to evaluate the contextually developed intervention in a better way.

Study outcomes

Quality of life

Quality of life will be measured through a Licensed MacNew Heart—health-related quality of life instrument (Urdu version). It will be measured at baseline (1 day following the procedure), 3rd month and 6th month postdischarge.

Cardiac health behaviour

The health behaviours of cardiac patients will be measured by health protective behaviour CHB-K21 questionnaire. It will be measured at baseline (1 day following the procedure), 3rd month and 6th month postdischarge.

Emergency hospital visits

It will be measured by the frequency of unplanned hospital visits. The data for unplanned hospital visits will be collected from participants through telephonic follow-up at 3rdmonth and 6th month postdischarge.

Cardiac anxiety

The anxiety related to cardiac events/procedures will be checked through Cardiac Anxiety Questionnaire (CAQ-18). It will be measured at baseline (1 day following the procedure), 3rd month and 6th month postdischarge.

Bio-physiological parameters

Systolic and diastolic BP, heart rate, blood glucose, body mass index, LDL, high-density lipoprotein, triglyceride and haemoglobin. Data for all the above parameters will be collected on the follow-up visits at baseline, at 3rd month and 6th month.

Study phase I (qualitative)

Research population

Patients who recovered from MI and have been treated (medically and/or with PCI) for CADs for the last 6 months at Mayo Hospital Lahore, and healthcare providers including cardiac nurses, cardiologists, physiotherapists, nutritionists, pharmacists and psychologists will be approached individually from different tertiary care hospitals will be population for the phase I of this study.

Sampling strategy

The purposive sampling technique will be used to invite patients and healthcare providers for semi-structured qualitative interviews. The purposive sampling technique is the most common method used in qualitative research.²¹

Sample size

The sample will be considered adequate once data saturation is achieved. Tentatively, the study is expected to enrol 15–20 participants for qualitative interviews.²²

Study phase II (quantitative)

Research population

Patients with acute coronary syndrome (STEMI or NSTEMI and/or unstable angina) will be the population for phase II.

Sample size determination

The sample size is calculated using the formula of a randomised controlled trial with continuous outcomes using the following parameters:

$${\displaystyle n_{trt}=\frac{{\left(Z_{1-\frac{\alpha }{2}}+Z_{1-\beta }\right)}^2\left[{\sigma }_{trt}^2+\frac{{\sigma }_{con}^2}{r}\right]}{{\mathrm{\Delta }}^2}}$$

$${\displaystyle r=\frac{n_{con}}{n_{trt}},\mathrm{\Delta }={\mu }_{trt}-{\mu }_{con}}$$

Mean quality of life in a treatment group=80.80, SD in a treatment group=13.70.²³

Mean quality of life in a control group=73.20, SD in a control group=13.00.²³

Ratio (control/treatment)=1.00.

Alpha (α)=0.05, Z (0.975)=1.959964.

Beta (β)=0.20, Z (0.800)=0.841621.

Calculated sample size: treatments=49, controls=49.^{24 25}

The calculated sample size is 49 for each group.

After adding a 20% dropout rate, the final sample size is=59 participants in each group.

Recruitment

The subjects will be assessed based on the eligibility criteria through a screening checklist by the researcher. The researcher will obtain written informed consent from the eligible patients; they will be informed about the purpose of the study, objectives, potential risks and benefits, data collection procedure and outcome of the study.

Allocation

Eligible subjects willing to participate will be referred to an independent allocator who will have sealed opaque envelopes containing codes for both groups. The allocator will be blinded to the codes and their meaning. Envelopes will be mixed well to ensure the prevention of selection bias. The allocator will open an envelope for each subject and assign him or her codes. The allocator will share the list of patients containing their names, and assign codes, and contact numbers to the researcher. The researcher will then divide the patients based on the coding system he developed to allocate study subjects to either control or interventional groups. The patients will be kept unaware of their group assignment, however, they will be provided with an intervention if they are assigned to an intervention group. Since the intervention will be on an individual basis, therefore, the study subjects will be blinded for: (1) their group assignment (subjects will not be informed about the group they are in) and (2) from the intervention or control group and vice versa.

Blinding

In this study, the independent outcome assessors and the patients will be blinded to group assignment. In health, behaviour, and rehabilitation interventions, blinding the investigator/researcher or subjects is difficult; the outcome assessor can be blinded to the group assignment.²⁶

Data collection methods

Phase I (qualitative)

Interviews will be performed using an interview guide created from the literature, supported by the premise of stressors in the Betty Neuman System model, and discussions among the fellow and supervisory team. After obtaining informed written consent, patients will be invited for semi-structured interviews in the language of their choice (Urdu, Punjabi and English). Interviews will take 45±10 min and will be taped and transcribed. The transcripts will be double-checked by an Urdu expert/colleague. It will improve the data’s consistency and accuracy. The goal of the interviews is to learn about self-management strategies participants adopted during their rehabilitation phase. Patients’ comfort will be taken into consideration.

Phase II (quantitative)

The assessors will be trained by the researcher to collect the baseline data for quality of life, health behaviours, bio-physiological parameters and cardiac anxiety through validated questionnaires. To prevent detection bias, the outcome assessors will be blinded to group allocation. No information will be shared with the assessors regarding the groups’ allocation. They will be asked to collect data from all study subjects by meeting them during the physical follow-up. The researcher with the help of secret coding will segregate the collected data. Following the baseline data collection, the intervention will last up to 12 weeks with additional 12 weeks of follow-up. One nurse will be trained to administer the intervention with the researcher. The conventional group will receive usual care, whereas, the intervention group will receive usual care with HBCR. The data for quality of life, health behaviours, bio-physiological parameters and cardiac anxiety will be collected at baseline (1 day following the procedure), 3rd month and 6th month intervals from both groups. Whereas the data for emergency hospital visits from both groups will be collected at the 3rd month and 6th month intervals (figure 1).

Figure 1.

This figure depicts the overall flow of randomised control trial in the second phase of the study. Beginning with the screening of eligible study subjects, their enrolment, randomisation into two different groups, duration of intervention, follow-up, data collection point times and then the final analysis. Study timeline: this timeline illustrates a tentative timeframe for all the research activities including qualitative data collection, training of data collectors, predata collection, intervention, postdata collection, data entry, analysis, write-up and submission. HBCR, home-based cardiac rehabilitation.

• At the beginning of the consent process, a schedule will be shared with the patients mentioning how long their participation will be required to allow them to think about their willingness to participate. To make them more clear, the duration of the intervention, its phases, and intervals of data collection and follow-ups (physically and telephonically) will also be made understood to them.

• Patients will be followed physically in the clinics of Mayo Hospital Lahore while for their off-clinic weeks, they will be given a phone call to monitor their progress regarding intervention.

• For physical follow-ups, patients will be compensated for their travel expenses.

• Researchers will make the process of data collection as convenient as possible for patients to allow their maximum retention until the completion of the study.

The researcher will transcribe interviews into audio-recorded verbatim. The transcriptions will be confirmed by the participants for the accuracy of the information they shared during the interview. The inductive coding approach will be used for thematic analysis to examine the data collected during these interviews. The data will be organised and reduced by identifying codes emerging from the data. The code will be combined to develop categories. Then, similar categories will be used to develop themes. The data will be analysed and added to as needed during the process.

The researcher will do the first data entry. To minimise the errors and ensure data accuracy, an independent data entry operator will also be hired for double data entry. The data will be entered and analysed through SPSS V.24.0. After ensuring the normality, the data will be analysed through descriptive (mean, median, mode) and inferential statistics such as dependent t-test/Wilcoxon signed-rank, independent t-test/Mann-Whitney U and repeated measures analysis of variance/Friedman to see the difference within the groups, between groups, and between three intervals, respectively. The data from patients who withdraw or do not complete the follow-up will be analysed after seeking permission from them.

Risk management plan

In this study, patients with mild to moderate risk will be recruited. For instance, before entering into second phase of CR, a submaximal exercise test; the 6MWT will be used as qualifying as well as for initiating the exercise prescription. The minimum distance required to qualify will be 150 m for non-surgical patients. The 6MWT will be performed in a hospital setting for patients with stable angina, post-PCI, and with >7 days following MI. This test will ensure the risk status of the patients and allow researchers to select patients with minimal risk for the second phase of HBCR. However, in case of any adverse event, the following actions will be taken as part of the risk management plan:

• The patients will be taught to take caution and stop physical activity/exercise if they feel chest discomfort, chest pain, unexpected shortness of breath, nausea, dizziness, palpitations, excess sweating or feeling of being unwell and report the same immediately to the researcher on personal contact provided on the consent form.

• The cardiologist in the research team will be on board to analyse the symptoms and guide the immediate treatment.

• In case any patient needs hospitalisation during the intervention, transporting the patient via ambulance and treatment expenses will be compensated from the amount of the research budget.

Patient and public involvement

We incorporated input from cardiac patients and members of the public during the design of this protocol. Patients who suffered a heart attack were involved to identify their basic health needs during the recovery period, which helped the research team to formulate research objectives and questions. The outcome measures were prioritised according to patients’ experience and affected health needs. The research tools were translated into a local language (Urdu) and presented to patients and members of the public to assess the readability of the tools and understanding of questions.

The qualitative interview guide was developed after the exploration of patient needs during their recovery period based on the concepts of the NSM. The basic design and components of HBCR intervention were outlined after the involvement of patients (n=4), their family members as part of the public (n=4) and healthcare professionals (n=3). Furthermore, the intervention booklet will be developed with the help of patients’ involvement in assessing the burden, frequency and time of intervention needed to follow at home.

Ethics and dissemination

The Ethical Review Committee of Aga Khan University and Mayo Hospital Lahore under the registration number 2023-8282-24191 and No/75749MH have approved this study protocol, respectively. Researchers shall follow ethical criteria that safeguard research participants from harm and ensure that their permission is based on information and awareness about the study, that participation is voluntary, and that the researcher adheres to confidentiality and anonymity regulations. The researcher will conduct the informed procedure without coercion or improper influence.²⁷

Informed consent

The researcher will obtain written informed consent from the study subjects; they will be informed about the study’s purposes, objectives, potential risks and benefits, data collection procedure and outcome of the study. The consent will be taken in the Urdu language. The study participants/subjects will be given enough time to ensure their understanding of the research. The researcher will answer any query about the study.

All participants in the study will be told that they will have the option to withdraw their consent at any time. The participants would never be pressured or influenced by the researcher to continue once the decision to withdraw permission is made. Furthermore, participants would not be required to give any reasons for withdrawing their agreement, and the withdrawal of consent would have no ramifications. Furthermore, any data provided by the participant who withdraws from the study will be deleted if s/he desires or will be included if s/he agrees.

Anonymity and confidentiality

The research procedure necessitates anonymity and confidentiality. When participants’ data are not connected to their identities, anonymity is achieved. However, qualitative research approaches make this difficult because the researcher is aware of the participants’ identities.²⁸ As a result, the researcher will take steps to protect their identities. Each participant will be given a code number and a pseudonym in this study. Any mention of a health service, a doctor, a family member or a significant other that may disclose the participants’ identities will be removed.

Dissemination

The research team intends to disseminate the study results to the research participants (in the Urdu language). The results will also be disseminated to healthcare professionals and the public by publishing the manuscript in an open-access peer-reviewed journal and presenting it at different conferences.

Protocol amendments

Changes in the protocol or any plan will be communicated to AKU-ERC and ANZCTR through an online portal. A request would be generated to update the trial information.

Ethics statements

Patient consent for publication

Not applicable.