Quadricuspid aortic valve

Associate Editors-In-Chief: ; Keri Shafer, M.D. [mailto:kshafer@bidmc.harvard.edu]

Overview
Quadricuspid aortic valve is a rare congenital anomaly and usually found at surgery or diagnosed preoperatively during echocardiographic examination or aortography.

The most common hemodynamic abnormality associated with this anomaly is aortic insufficiency.

Embryology
The semilunar valves are derived from mesenchymal swellings in the aortic and pulmonary trunk after the truncus arteriosus has been partitioned.

It is in the early stages of truncal separation that four subendothelial buds appear instead of three.

The presence of a corpus arnatii on all four cusps indicates that the valve resulted from abnormal embryogenesis.

History
The first known case report was written by Balington in 1862.

The prevalence of quadricuspid aortic valve is (by historical autopsy review) approximately 0.008%. A modern echocardiography database review showed the prevalence to be somewhat higher, depending on the years reviewed (0.013%–0.043%).

Pathophysiology
On pathological descriptions the aortic valve has four cusps:
 * a posterior cusp,
 * a left coronary cusp,
 * a right coronary cusp,
 * an anterior supernumerary cusp.

Raphes join the supernumerary cusp with the left and right coronary cusps. The raphes have been described as shallow and chordlike. The supernumerary cusp can have multiple fenestrations.

The cusps can vary in;


 * Size,
 * Thickness
 * Pliability

Classification

 * Four equal cusp,
 * Three equal large and one small cusp (the most common type),
 * Two equal large and two equal small cusps,
 * One large, two equal intermediate and one small cusps,
 * Three equal small and one larger cusps,
 * Two equal large and two unequal smaller cusps,
 * Four unequal cusps.

Associated cardiac abnormalities

 * Displaced coronary ostia
 * Single or accessory coronary ostia
 * Isolated coronary ostium
 * Patent ductus arteriosus
 * Congenitally deficient mitral leaflets
 * Ventricular septal defect
 * Fibromuscular subaortic stenosis
 * Non-obstructive hypertrophic cardiomyopathy
 * Aortic insufficiency (the most common)

Echocardiography

 * Quadricuspid Aortic Valve 1

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 * Quadricuspid Aortic Valve 2

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 * Quadricuspid Aortic Valve 3

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 * Quadricuspid Aortic Valve 4

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 * Quadricuspid Aortic Valve 5

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 * Quadricuspid Aortic Valve 6

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 * Quadricuspid Aortic Valve 7

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 * Quadricuspid Aortic Valve 8

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 * Quadricuspid Aortic Valve 9

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Pathological Findings
Image courtesy of Professor Peter Anderson DVM PhD and published with permission © PEIR, University of Alabama at Birmingham, Department of Pathology