Case presentation: A 60-year-old female patient presented with a 10-day history of shortness of breath and exertional angina, with ischemic heart disease, mitral regurgitation, heart failure 5 years ago. Her physical examination revealed a grade III/VI systolic murmur over the apex. Electrocardiogram showed normal sinus rhythm with left ventricular enlargement, poor R wave progression in the precordial leads. The patient’s echocardiographic imaging revealed dilated left-sided heart chambers, as well as reduced left ventricular ejection fraction (43%), severe mitral valve insufficiency and elevated systolic pulmonary artery pressure (60 mmHg). Multislice computed tomography with three dimensional reconstruction showed that the left main coronary artery originated from posterior side of the main pulmonary artery, confirming the diagnosis of ALCAPA (Figure). The patient was treated by ligation of the left coronary artery from the pulmonary artery combined with coronary artery bypass grafting and mitral valve repair.
Discussion: 85% of all cases of ALCAPA present within the first two months of life. However, symptoms may be misinterpreted (as in our case) or even be absent. In adult life patients with ALCAPA could present with symptoms of heart failure, mitral valve insufficiency, angina or arrhythmias. Objective findings include cardiomegaly on chest X-ray, and ECG may display an anterolateral infarct pattern. The diagnosis can often be made by two-dimensional echocardiography with direct visualization of the abnormal origin of the left coronary artery and retrograde flow into the pulmonary artery. In cases where the clinical suspicion is strong, a coronary angiography or CT-angiography should be performed.
Conclusion: the diagnosis of ALCAPA should be considered in adults without evidence of ischemic heart disease presenting with arrhythmias, left sided heart failure with or without mitral valve dysfunction, since an early diagnosis and surgical treatment generally results in an excellent prognosis.