Discovering the unforeseen. MINOCA in the setting of stented aortic coarctation resulting in heart failure, the value of cardiac magnetic resonance beyond mere morphological assessment. (QF_SA_111)

Aortic coarctation is a cardiac condition that frequently occurs in young patients and can lead to significant cardiovascular complications. In this context, the assessment of hemodynamics and ventricular function is essential for the appropriate management of these patients, particularly those who have undergone interventions such as the placement of aortic stents. Cardiac Magnetic Resonance (CMR) with tissue characterization, angiography and added sequences as 4D Flow is a comprehensive tool for the non-invasive evaluation of these aspects.

We present the case of a 38-year-old male patient with history of a stented aortic coarctation. Over the past three months, the patient experienced increased shortness of breath during exercise and an increase in blood pressure, requiring up titration of his treatment. The physical examination revealed a discrete murmur in the dorsal region, while the electrocardiogram showed signs of left ventricular hypertrophy and the  transthoracic echocardiogram  mild ejection fraction impairment but inconclusive due to suboptimal acoustic windows.

Diagnostic Techniques and Their Most Important Findings:

An ungated aortic computed tomography revealed left ventricular dilation and a patent aortic stent with a small dilatation distal to the stented area. (Image A.)

Evaluation with CMR was performed using a 1.5 Tesla machine, which included several sequences both before and after gadolinium administration. The cine images showed regional hypokinesia in the lateral and inferior walls of the left ventricle, with a slightly reduced ejection fraction (49%). The 4D Flow sequences demonstrated the presence of flow vortices post-stent, with a maximum velocity of 1.6 m/s and a significant "diastolic tail", suggesting hemodynamically significant stenosis (Image B). Also, the aortic angiography and aortic arch cines showed an small aneurysmatic area distal to the stent. The inversion recovery sequences showed subendocardial late gadolinium enhancement in the inferior and lateral walls (Image C.). These findings led to the performance of an invasive coronary and aortic angiography, which confirmed the presence of a peak to peak  gradient of 20 mmHg across the stent and the abscense of significative coronary stenosis ,  stablishing the diagnosis of MINOCA and upper -normal aortic gradient.

Learning Points from this Case:

This case highlights the utility of CMR , as it allows for non-invasive hemodynamic evaluation in patients already treated for aortic coarctation through the analysis of aortic diameters, hemodynamic assessment using phase contrast and 4D flow, and especially the comprehensive analysis of myocardial tissue. In this case, the diagnosis of MINOCA was established as the main contributor to the patient's clinical deterioration, along with indirect data suggestive of re-coarctation.