Aortic valvar atresia with ventricular septal defect with well-developed mitral valve and balanced ventricles may mimic common arterial trunk.

Aortic valvar atresia is a congenital cardiovascular malformation in which there is no patency of the aortic valve, and thus no communication between aorta and either ventricle. A hypoplastic ascending aorta is a constant feature, usually in the context of a small left ventricle and mitral valve. A subset of this group is aortic atresia with a ventricular septal defect with well-developed mitral valve and balanced ventricles. This morphological variant is often misdiagnosed as common arterial trunk on echocardiography and computerised tomography. In the absence of coarctation or focal narrowing of the aortic arch, one can misdiagnose this entity as common arterial trunk with a single coronary artery from the brachiocephalic artery. Patients with this variant may have hypoplastic left heart physiology, but can potentially undergo a biventricular repair. Herein, we describe aortic valvar atresia with a large pulmonary trunk and ventricular septal defect, with balanced ventricles and a well-developed mitral valve. The patient was originally misdiagnosed as having a common arterial trunk. We emphasise the morphological differences, as well as the surgical importance, including technical considerations, conduction of cardiopulmonary bypass, and myocardial protection.