Bicuspid Aortic Valve and Associated Aortopathy: Surgical Considerations

Introduction

The human aortic valve is normally a tricuspid structure but may occur as bicuspid or quadricuspid structures (Figure 1). Bicuspid aortic valve (BAV) is one of the most common congenital heart anomalies and the most common congenital anomaly in adults, occurring in 0.5-2% of the population based on echocardiography and autopsy series.^{1, 2} It is an inherited defect that appears to occur in an autosomal dominant pattern. BAV is the cause of aortic stenosis in 70-85% of pediatric cases³ and about 50% of adult cases.⁴ Indications for aortic valve replacement (AVR) in BAVs is the same as rheumatic or senile calcific degeneration aortic valves. BAVs are different, however, in that the tissue pathology is not limited to the valves’ leaflets but extends from the left ventricular outflow tract to the ascending thoracic aorta. BAVs are associated with several congenital anomalies, infective endocarditis, and acute thoracic aortic emergencies such as aneurysm and dissection. These associations lead to surgical considerations different from other aortic valve pathologies.