Open heart surgery. Aortic valve removed during surgery to replace a bicuspid aortic heart valve (BAV) and part of the aorta (the body's main artery). The aorta had become dilated due to the BAV. BAV is a congenital defect of the aortic valve where it has two cusps (sealing flaps) rather than the usual three. This can disrupt the flow of blood from the heart to the aorta and reduce the strength of the descending aorta, leading to an increased risk of dilation or aneurysm.