LAUSR

Introduction: Anomalous aortic origin of a right coronary artery (AAORCA) may lead to myocardial ischemia (ISCH) and sudden death in the young. Current guidelines deem asymptomatic patients (pts) low-risk if normal exercise stress test (EST). Hypothesis: The frequency of ISCH in AAORCA pts is seen more commonly on stress perfusion imaging (sPI) compared to EST. Method: Pts <21 yrs with AAORCA were prospectively enrolled and managed following a standardized approach (12/2012-04/2020). Coronary CTA was used to define details of AAORCA. EST and sPI were performed in pts >7 yrs and in younger pts if concern for ISCH. sPI included nuclear imaging initially and dobutamine stress cardiac MRI since 06/2014. High-risk features included intramural length (IML), abnormal ostium, symptoms or evidence of myocardial ISCH. Shared decision-making directed medical/surgical management. Results: Of 220 pts (male 135, 61%) enrolled at median age of 12 [IQR 6-15] yrs, 168 (76%) had no/non-exertional symptoms (Group-1) and 52 (24%) had exertional chest pain/syncope (Group-2). Coronary CTA was available in 180 and EST in 164 pts. EST was positive in 2/164 (1%), both had positive sPI. Of 162 negative EST, inducible ISCH was seen in 10/96 (10%) in Group-1 and 8/42 (19%) in Group-2. No difference in IML was noted between pts with/without ISCH (5.7±2.4 vs 6.0±2.1 mm, p=0.6). Surgery was indicated in 67 (30%) pts with high-risk features, not indicated in 143 (65%), and 10 (5%) are undergoing evaluation. In 51 operated pts (38 unroofing; 13 translocation), 3 await post-operative assessment, 48 on normal physical activities; median follow-up of 4.6 [IQR 2.3-6.3] yrs. All patients were alive at last follow-up; median of 2.9 [IQR 1.2-5.1] yrs. Conclusions: AAORCA pts can present with reversible ISCH on sPI regardless of symptoms or IML. EST may be a poor predictor of ISCH and caution should be given to determine low-risk. Most high-risk patients return to exercise and remain well at medium-term follow-up.