![]() Bioprosthetic replacement approaches are effective, but not durable. Aortic valve replacement is the second most frequent cardiovascular surgical procedure, and the need for re-intervention is common. Therapy for CAVD remains primarily surgical and is restricted to late stage disease. Aortic valve sclerosis, a marker of cardiovascular risk, and to a lesser extent valve disease, is present in more than 25% of the aged. Aging is an independent risk factor for CAVD, resulting in a higher prevalence of disease as the population achieves greater longevity. The majority of valve disease at any age has an underlying valve malformation suggesting a genetic basis. Taken together, the public health impact and burden to society of CAVD is significant and underappreciated. The actual direct cost for valve disease in the US alone has been estimated at 1 billion dollars per year. Greater than 2.5% of the population has AVD, causing more than 25,000 deaths annually in the US. Human studies investigating valve disease have suggested that the base of the valve cusp and valve annulus regions is the origin of disease processes, including both sclerosis and calcification. Research efforts have focused on the valve cusp, and as a result the valve annulus has been largely overlooked. Histopathology from diseased valves explanted at the time of surgery from patients with CAVD demonstrates large nodules of overt calcification, in addition to cell-matrix abnormalities ( Figure 2). The diagnosis can be made clinically and confirmed by echocardiography, which quantifies the severity, and, over time, the progression of disease. Aortic valve stenosis is the most common manifestation of CAVD and classically presents as angina, syncope and heart failure. ![]() Ultimately, ventricular function can be compromised. Valve disease may manifest as stenosis, an obstruction to normal forward blood flow, or insufficiency, a defective closure resulting in backward blood flow. Aortic valve disease is defined by abnormal valve function. ![]() Ĭalcific Aortic Valve Disease is a growing public health problem. Rarely, a quadricuspid aortic valve (QAV, H) is identified. Bicuspid aortic valve (BAV) may manifest as fusion of the RL (E), RN (F), and rarely LN (G) commissures. UAV manifests as either partial fusion of all three commissures (red arrowheads, C) or complete fusion of both the RN and RL commissures (D). Three normal commissures are demonstrated in panel A, and normal opening of the commissures results in complete cusp separation to the wall of the aorta at the sinotubular junction (yellow arrowheads). Aortic valve malformation ranges from unicuspid (UAV) to bicuspid (BAV) to a thickened tricuspid (not shown) to quadricuspid (QAV) morphology. Distinct morphologies are based on fusion patterns of the commissures (dotted lines, B) as they relate to the right (R), left (L) and non (N) coronary sinuses of Valsalva (A). Normal tricommissural aortic valve (TAV) morphology is demonstrated in diastole (A) and systole (B). Aortic valve malformation Parasternal short axis echocardiographic views at the base of the heart showing the aortic valve en face (A-H). Phenotype definition: spectrum of aortic valve malformation. Presently, it remains unclear to what degree these variations of malformation represent true differences. In addition to BAV subtypes, there is a spectrum of aortic valve malformation ( Figure 1), ranging from various types of unicuspid to quadricuspid aortic valves with the three BAV morphology patterns and a thickened tricommissural aortic valve representing intermediate phenotypes. Rarely, cases have shown fusion of the left and non (LN) coronary cusps. Two patterns of BAV morphology are commonly observed: ~70% of isolated cases have fusion of the right and left (RL) coronary cusps with the remainder consisting almost entirely of those with fusion of the right and non (RN) coronary cusps. BAV itself is subclinical and the valve is typically functional, making BAV an endophenotype. ![]() ![]() The incidence of BAV is 1-2% in the general population and affects an estimated 3 million people. BAV is present at birth and is characterized by two rather than three cusps. Aortic valve malformation is the most common cardiovascular malformation (CVM), and bicuspid aortic valve (BAV, MIM#109730) is the most common type of aortic valve malformation. Aortic valve malformation has been appreciated since the Renaissance when artists advanced our understanding of anatomy and specifically, Leonardo da Vinci illustrated and described variants of aortic valve morphology. diseaseĪortic valve malformation is a spectrum including Bicuspid Aortic Valve. ![]()
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