Diagnosis of adult ALCAPA with computed tomography coronary artery

Background Anomalous left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital anomaly where the left main coronary artery arises from the pulmonary artery, instead of the coronary sinus of the ascending aorta. ALCAPA is divided into infant and adult types. Life-threatening complications such as malignant arrhythmia and sudden death could ensue in adult type of ALCAPA. Imaging is the current preferred modality for ALCAPA. It is indeed a challenge to diagnose ALCAPA due to its non-specific clinical presentation and laboratory findings. We report a case of adult type ALCAPA presented with unstable angina surprisingly surviving into adulthood with no symptoms prior to presentation, which is extremely rare. Case presentation A 53-year-old lady presented with sudden onset of chest pain and worsening shortness of breath. She was initially treated as unstable angina. Physical examination revealed normal heart sound. Computed tomography coronary angiography (CTCA) showed an anomalous origin of the left coronary artery from the posterior wall of the proximal pulmonary artery, compatible with ALCAPA. The anomalous left coronary artery bifurcates into left anterior descending and left circumflex arteries. Cardiothoracic surgeon planned for occlusion of ALCAPA via the pulmonary artery, owing to the fact that unfeasible rerouting in the presence of well-established collateral supply. Conclusions ALCAPA is a rare and life-threatening condition in adults which may lead to myocardial infarction and sudden death in untreated cases. CTCA is one of the preferred modern imaging modality in ALCAPA owing to its superior ability for direct visualization of the anomaly. Hence, early identification and surgical intervention of the anomaly are paramount to reduce the morbidity and mortality.