Multimodal Stress Testing and Morphologic Predictors of Ischemia in Anomalous Aortic Origin of a Coronary Artery

Abstract Background Anomalous aortic origin of a coronary artery (AAOCA) can cause myocardial ischemia and sudden cardiac death. The optimal stress-testing strategy and impact of coronary morphology on ischemia remain unclear. We assessed the effect of coronary morphology on stress-test completion and results across multiple test modalities. Methods This retrospective cohort study included 531 adults with AAOCA at our institution (7/2015 – 3/2023). Coronary morphology was characterized by the anomalous coronary (right [RCA], left main [LMCA], left anterior descending [LAD], left circumflex) and the course type (intramural, interarterial-only, transseptal, and other [prepulmonic and retroaortic]). Exercise and pharmacologic stress tests were positive if ischemia included the territory of the anomalous coronary. A mixed-effect logistic regression modeled the odds of a positive test based on morphology, comorbidities, and modality. A random forest regression analyzed the stress iFR as a continuous outcome. Results Stress test results were available for 396 (75%) of patients (age 50 ± 17 years; 42% female). Stress testing included 699 ECGs, 198 echocardiograms, 288 SPECTs, 133 PETs, and 103 dobutamine iFR studies. Completion of invasive dobutamine iFR (versus noninvasive-only) stress testing was associated with high-risk coronary morphology, p