Quadricuspid Aortic Valve: An Introduction for Clinicians

Quadricuspid aortic valve (QAV) is a congenital heart anomaly in which the aortic valve has four cusps of various size possibilities, as opposed to the three symmetrical cusps generally observed. This cardiac valvular abnormality is rarely identified, with an estimated incidence rate of 0.013% to 0.043%, although recent technological advancements in diagnostics have contributed to an increase in detection. Historically, it had been typically encountered during open heart surgery or postmortem; however, it is presently diagnosed primarily via ultrasound echocardiography, and could go undetected unless specifically considered. It was first reported by Babington in 1847, and since then approximately 300 cases have been published. This condition is sporadically associated with additional congenital cardiovascular defects, with coronary artery irregularities being the most common. In more than half of published QAV incidences it has led to the progressive development of aortic regurgitation (AR) usually sans aortic stenosis, particularly amongst elderly patients, often requiring surgical intervention after 50 years of age. A fifth of total instances, but two-thirds of instances with AR, warrant surgery seldom amidst complications, with reconstructive tricuspidization preferred over valve replacement.