Aortic regurgitation due to non-traumatic rupture of the aortic valve commissures: report of two cases.

Two cases of severe aortic regurgitation due to non-traumatic rupture of the aortic valve commissures are reported. The cause of rupture was hypertension in one patient, but it could not be identified in the other, where microscopic examinations of the aortic wall and the aortic cusps showed no particular pathologic changes. M-mode echocardiography revealed enlargement of the left ventricle, diastolic flutter of the anterior mitral leaflet and diastolic separation of the closure line of the aortic cusps in both patients. Two-dimensional echocardiography showed a downward displacement of the prolapsing motion of the aortic valve cusp during diastole toward the left ventricular outflow tract in one patient, and eccentricity of the coaptation point of the aortic valve without thickening of the cusps in the other. In addition to clinical features of progressive heart failure and characteristic cardiac murmur, echocardiographic studies provided correct diagnosis of aortic valve prolapse resulting from rupture of the aortic valve commissures. Both patients underwent aortic valve replacement successfully.