Untreated ALCAPA diagnosed in gestational ultrasonography.

ALCAPA is a rare congenital anomaly that presents with left ventricular (LV) dysfunction and mitral valve regurgitation. The mortality rate is roughly 90% if the intracoronary collateral isn't significantly augmented. Malignant arrhythmias resulting in sudden death are common, affecting nearly 90% of patients with a mean age of 35 years. Especially during pregnancy, untreated ALCAPA can lead to high mortality and complications. Pregnant women with congenital heart disease have high risks for both themselves and their fetuses. Therefore, screening for congenital heart disease is very important in early diagnosis, counseling, and management. Most women born with congenital heart disease (CHD) will reach reproductive age. We report a case of a 30-year-old woman in her second trimester of pregnancy who presents with ALCAPA, preserved ejection fraction (EF), and mild LV dilation. An uncommon feature, in this case, is the origin of the left main (LM) coronary artery from the posterior to the right of the main pulmonary artery (MPA), which is very close to the ascending aorta, mimicking the normal origin of the LM from the aortic root in 2D transthoracic echocardiography. The patient also has preserved left ventricular function with endocardial fibroelastosis. Echocardiography should be performed every 4 weeks to assess the progression of the disease during pregnancy.