Late diagnosis of severe aortic coarctation in a 65-year-old endurance athlete: Insights into exercise physiology and collateral compensation

Abstract

Background

Coarctation of the aorta (CoA) is a relatively rare congenital narrowing of the distal aortic arch to proximal descending thoracic aorta, usually diagnosed in infancy or early childhood with upper extremity hypertension as a typical finding. Late detection in asymptomatic, physically active older adults is rare and can be clinically significant.

Case presentation

We present the case of a 65-year-old lifelong endurance athlete found to have transient severe left ventricular (LV) systolic dysfunction after completing a marathon. Stress testing revealed a hypertensive response, prompting cardiac MRI, which detected a new severe juxta-ductal CoA with collateralization. The patient underwent successful endovascular stenting with improved blood pressure response and stabilization of LV function.

Conclusion

This case underscores the importance of thorough cardiovascular assessment in older athletes and highlights the impact of lifelong exercise in compensating for congenital defects like CoA.

1. Introduction

Coarctation of the aorta (CoA) is a congenital narrowing of the aorta accounting for 5 % of congenital heart defects and usually diagnosed in early life before 10 years of age [1,2]. A late diagnosis in older lifelong athletes, without prior medical history is uncommon. Late presentations in older adults, particularly in those without symptoms, are often attributed to well-developed collateral circulation which, compensates for the aortic arch stenosis. In highly trained lifelong endurance athletes, adaptive cardiovascular changes such as relatively lower blood pressures (BP), increased stroke volume, and slower resting heart rates compared to non-athletes may additionally mask clinical signs, delaying diagnosis.

2. Case presentation

2.1. Patient history and diagnostics

A 65-year-old male, asymptomatic, lifelong athlete presented to his primary care doctor for general assurance that he could continue his high-volume exercise regimen. He had no significant personal or family medical history. His lifestyle included long-distance running, weightlifting, SCUBA diving and high intensity strength and conditioning workouts. A week prior to evaluation, he completed a marathon with sustained heart rates of more than 120 bpm for over 6 hours without any distress.

Initial examination revealed a resting blood pressure of 130/65 mmHg and bradycardia (40 bpm). Initial transthoracic echocardiography (TTE) showed a severely enlarged left atrium (LA) (volume index: 50 mL/m²), a moderately to severely enlarged left ventricle (LV) (end-diastolic diameter: 67mm) (Image-1, Image-2) and a reduced LV ejection fraction (EF) of 35 %. Moderate aortic regurgitation and aortic root dilation (45 mm) were noted. A treadmill single photon emission computed tomography (SPECT) stress test showed a peak heart rate of 144 bpm (93 % predicted), a hypertensive response (peak BP 260/70 mmHg) and a small apical reversible perfusion defect. CT angiogram revealed mild non-obstructive CAD.

Image-1.

TTE showed: severely enlarged left atria with LA Volume Index- 50ml/m.².

Image-2.

TTE showed: moderate to severely enlarged left ventricle with LV end systolic diameter- 67mm.

The patient was then referred to a cardiovascular specialty institution for further evaluation. On cardiovascular exam, a 2/6 systolic murmur was noted in the left infraclavicular area. BP discrepancies included 149/69 mmHg (left arm), and 130/82 mmHg (left leg). Femoral pulses were delayed compared to radial. Repeat TTE revealed LVEF recovery to 63 % but persistent LA and LV dilation; additionally, a previously unapparent, bicuspid aortic valve was identified with partial left-right cusp fusion, mild aortic regurgitation without aortic valve stenosis. EKG revealed marked sinus bradycardia (37 bpm). Laboratory results including complete blood count, comprehensive metabolic panel and fasting lipid profile were within normal limits. Given the unexplained transient decrease in LVEF and high BP response on exercise stress test, a cardiac MRI (CMRI) was ordered (Image-3), which identified severe juxta-ductal aortic coarctation with an effective area of 0.46 cm²/m² and a lumen diameter of 8 mm with post-stenotic dilation. Collateral flow was observed, with prominent brachiocephalic, subclavian and internal mammary arteries, indicating hemodynamic significance. There was no evidence of significant myocardial late gadolinium enhancement (LGE) to suggest infiltration, inflammation, or scarring. The repeat cardiac CT angiogram was consistent with the CMRI findings, confirming the presence of a post-ductal aortic coarctation (Image-4).

Image-3.

Cardiac MRI showed: severe aortic coarctation (red arrow) 5cm distal to left subclavian artery , with mild post-stenotic dilation, prominence of brachiocephalic, subclavian, internal mammary artery and collaterals (blue arrows).

Image-4.

CT Cardiac Angiography showed-post-ductal coarctation located approximately 5cm distal to the left subclavian artery (red arrow).

2.2. Management and intervention

Management included initiation of metoprolol succinate 25mg/day and losartan 12.5mg/day. Given the diagnosis of severe juxta-ductal coarctation of the aorta, successful endovascular repair was performed, involving 10-cm Gore TAG stent graft placement followed by balloon angioplasty (Image-5).

Image-5.

Cardiac catheterization image post-stent placement with 10 cm Gore TAG graft which improved the luminal waist from 8 mm to 24 mm.

2.3. Procedure outcome and follow-up

Post-procedure, the peak-to-peak systolic gradient at the coarctation site improved from 34 mmHg to no residual gradient and the luminal waist improved from 8 mm to 24 mm. Chest radiography confirmed intact graft placement and magnetic resonance brain angiogram ruled out any associated berry aneurysms. Follow-up TTE showed normal LV systolic function (EF 55 %), with no significant descending thoracic aorta gradient but persistently enlarged cardiac chambers. Two months after the vascular repair, a maximal effort cardiopulmonary exercise test showed an 80 mmHg decrease in peak exertional systolic BP with excellent peak volume of oxygen uptake (VO2) of 36.9 mL/min/kg (123 % predicted). A year later, exertional capacity remains intact based on stress testing and he continues to perform high volumes of exercise.

3. Discussion

CoA is usually diagnosed early in life, with rare cases [[3], [4], [5], [6], [7], [8], [9]]^- identified after age 40 [10]. This case illustrates a rare, late presentation of severe CoA in a lifelong endurance athlete. In such individuals, compensatory collateral formation and physiological remodeling may delay symptom onset.

Generally, untreated coarctation of the aorta (CoA) is associated with significant morbidity and mortality. It increases left ventricular workload, resulting in ventricular hypertrophy and sustained hypertension, which predispose patients to severe complications such as congestive heart failure (26 %), aortic rupture (21 %), bacterial endocarditis (18 %), and intracranial hemorrhage (12 %). In one series, 90 % of untreated patients die before the age of 50, and an additional 5 % between the ages of 50 and 60 [11]. This patient's CoA had been largely asymptomatic with preserved supranormal functional status for years, likely due to extensive network of collateral vessels which maintained distal blood flow and allowed him to exercise at high volume. Given that exercise is known to help collateral vessel formation (angiogenesis and arteriogenesis) with chronic total coronary occlusions [12], it is possible that his lifelong exercise contributed to the extent of collateral blood flow that was formed. This compensatory mechanism could explain the prolonged survival and low clinical expression observed in some older patients [3,7], until it reaches a critical point, as in this case, where exertional hypertension and transient post-exercise left ventricular dysfunction was seen. Persistently high blood pressure related to his coarctation during the marathon may have caused transient stress cardiomyopathy-like myocardial contractility depression as no injury was seen on cardiac MRI to explain the temporary reduction in LVEF.

The bicuspid aortic valve (BAV) identified in this patient is consistent with the 50–70 % CoA-BAV association, stemming from common embryologic origins [13]. Given BAV as the most common congenital heart disease with prevalence of 0.5–2 % in general population [14], aortic coarctation should always be ruled out in such patients.

A clinical lesson highlighted by this case is the role of careful peripheral pulse examination, particularly the femoral pulse, in routine cardiovascular assessment. The presence of delayed or diminished femoral pulses relative to upper limb pulses is a classic and important physical finding suggestive of aortic coarctation. Despite advances in imaging, bedside detection of these discrepancies remains invaluable for early recognition, especially in settings where imaging may be delayed or unavailable.

Additionally, accurate measurement of differential blood pressures plays a vital role in the evaluation of suspected CoA. In most cases, it is recommended to compare the right arm and leg pressures, as the left subclavian artery can be involved in or distal to the coarctation segment. This can result in falsely lower blood pressure readings in the left arm, potentially masking the true degree of upper-to-lower extremity gradient. However, anatomical variations such as aberrant right subclavian artery should also be considered, as they can alter the hemodynamic profile and affect interpretation of pressure gradients.

The inappropriate hypertensive response on exercise stress test in this physically active male with no other risk factors led to further assessment confirming the severe CoA on CMRI. MRI remains the preferred imaging modality for assessing CoA and follow-up post-stenting due to its ability to non-invasively quantify flow and detect residual gradients or aneurysms without radiation [15]. The patient's persistent left atrial and ventricular dilation were likely related to his lifelong, high volume of exercise and possibly due to his higher exertional blood pressures. His strong peak VO2 result on cardiopulmonary exercise testing and his CMRI showing no signs of myocardial inflammation or scarring suggests more physiological than pathological remodeling.

Interestingly, in our case, the initial CT coronary angiography ordered to assess obstructive coronary disease and performed in a lower volume radiology center, failed to detect the CoA in this patient, possibly because the field of view was limited to the heart, excluding the aortic arch, highlighting the importance of thoroughly reviewing all available imaging and keeping a broad differential.

The most recent guidelines from the Joint Committee of the American Heart Association/American College of Cardiology (2022) on Clinical Practice [16] and the European Society of Cardiology (2020) [17] recommend interventional therapy for aortic coarctation under three scenarios [1]: peak-to-peak pressure gradient greater than 20 mmHg on catheterization [2]; gradient over 10 mmHg accompanied by reduced left ventricular systolic function or notable collateral circulation; and [3] in hypertensive patients with more than 50 % narrowing of the aorta compared to the diaphragmatic aortic diameter, as shown by MRI, CT, or angiography, regardless of gradient.

In our 65-year-old patient, cardiac catheterization revealed a peak-to-peak gradient of 34 mmHg and the presence of significant collateral vessels—meeting the criteria for interventional therapy. The minimally invasive endovascular treatment was preferred in this case due to its proven efficacy in older patients, excellent immediate outcomes, faster recovery and cost-effectiveness. Surgical repair, in contrast generally reserved for neonates, infants and in complex anatomical coarctations [[18], [19], [20]].

The patient underwent successful endovascular stenting and balloon angioplasty, resulting in significant improvement of his exercise-induced hypertension based on CPET. This case illustrates the effectiveness of this approach, as well as the importance of timely intervention to prevent further complications. It also highlights the importance of considering CoA in older individuals, even in the absence of typical symptoms, as it can remain undiagnosed for many years due to compensatory mechanisms. The patient's favorable outcome following intervention highlights the importance of comprehensive cardiovascular evaluation in athletes to detect any underlying cardiovascular abnormalities that may not be apparent at rest.

4. Conclusion

This rare case of late-diagnosed severe aortic coarctation in an older endurance athlete, characterized by exercise-induced hypertension and temporary left ventricular dysfunction, underscores the need for high clinical suspicion and multimodal imaging. Thorough evaluation including physical examination, timely diagnosis, and intervention can prevent complications and allow safe return to full physical activity.

5. Learning points

• •Aortic coarctation can remain undiagnosed in older endurance athletes due to extensive collateral development and adaptive cardiovascular remodeling.
• •Exertional hypertension in athletes warrants clinical suspicion for structural heart disease, including aortic coarctation.
• •MRI is a valuable modality for both diagnosis and follow-up in adult aortic coarctation.
• •Endovascular stenting is effective and safe in older aortic coarctation patients, supporting functional recovery.

CRediT authorship contribution statement

Arundhati Sharma: Writing – original draft. Anubhuti Sharma: Writing – original draft. Kalyan Chaliki: Writing – review & editing. Marco Antonio Fernandes: Writing – review & editing. Francois Marcotte: Writing – review & editing. Satyajit Reddy: Writing – review & editing, Supervision.

Informed consent statement

The patient consented to the publication of his case report, including any relevant medical information and images, and understood that his identity would be protected and that the publication was for educational and research purposes.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.