Introduction: Anomalous aortic origin of a coronary artery (AAOCA) can result in sudden cardiac death in the young and risk stratification is challenging. Though dobutamine stress cardiac MRI (DS-CMR) is feasible in pediatric patients, exercise stress CMR (ES-CMR) has lower rates of adverse events, higher diagnostic accuracy, and the ability to better reflect the physiologic changes occurring with exercise. No studies have evaluated ES-CMR in the pediatric population. We aim to describe our institution’s experience with ES-CMR using supine bicycle ergometry in patients with AAOCA. Methods: We retrospectively reviewed the medical records of AAOCA patients who underwent ES-CMR at our institution between 2011 and 2024 for demographic, clinical presentation, cardiopulmonary exercise test (CPET) and ES-CMR data. The exercise-based portion of the CMR consisted of supine cycle ergometry utilizing a ramp protocol, immediately after which perfusion imaging was performed. We used descriptive statistics for data analysis. Results: Of 38 patients who underwent ES-CMR, the median age was 16 years (range 13-24) and 68% were male. Diagnoses included anomalous right coronary artery (N=28), anomalous left coronary artery (N=8), and single coronary artery (N=1 single right, N=1 single left). Median maximal heart rate (HR) during ES-CMR was 160 bpm (range 130-190, median 80% predicted) with a median maximal HR during patients’ most recent CPET of 187 bpm (range 160-203, median 97% predicted). No patients had perfusion defects at rest or with exercise stress, or evidence of myocardial scarring. There were no adverse events. Discussion: We demonstrate for the first time the use of ES-CMR in a cohort of pediatric and young adult patients with AAOCA. ES-CMR can provide a unique modality to assess for ischemia at rest and stress as a means of risk stratification and simulate physiologic changes occurring with exercise stress in a single study. Although maximum heart rates during supine cycle ergometry are lower than those reached during CPET, they are similar to those reached during DS-CMR. ES-CMR can be a helpful and safe diagnostic tool in patients with AAOCA.
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