Aortic regurgitation with dove-coo murmur with special references to the mechanism of its generation using dual echocardiography.

Triphasic dove-coo murmur in a patient with aortic regurgitation was studied as to the mechanism of its generation using simultaneous recording phonocardiography and dual echocardiography. The murmur arose coincident with the coarse regular fluttering of aortic posterior wall during the opening of mitral valve and decreased coincident with the protrusion of mitral valve anterior leaflet into the left ventricular outflow tract. Thus the murmur might occur, provided that normal mitral valve opening and closure was maintained. It may well explain why the murmur hardly occurs in aortic regurgitation of rheumatic origin in which rheumatic lesion often is thought to involve mitral valve, restricting mitral opening during diastole and thereby inhibits aortic root vibrations.