Aortic regurgitation caused by dilatation of the aortic orifice and associated with a characteristic valvular lesion

Abstract

Some persons, mostly men beyond middle age, exhibit signs of aortic regurgitation which is not caused by syphilis, rheumatic heart disease, bacterial endocarditis, or arteriosclerotic degeneration. Hypertensive cardiovascular disease is usually present. This type of aortic regurgitation may be unaccompanied by most of the peripheral phenomena which are characteristic of aortic insufficiency of infectious origin. The diastolic murmur is usually merged with an accentuated aortic second sound. Patients with this lesion eventually die of congestive heart failure. Precordial pain is infrequent. Auricular fibrillation is common. Dilatation of the aortic ring is present in most cases. Occasionally, only supravalvular dilatation of the aortic arch occurs. In all cases the aortic leaflets appear insufficient to meet the need of increased coverage. They often show compensatory elongation. Depending on the length of the survival period, there is a variable development of structural changes in the aortic leaflets; this is apparently secondary to the dilatation of the aortic ring and is brought about by the eroding action of slow leakage. The change consists of a sclerotic thickening of the midportion of the free margin of the leaflet, without involvement of the commissures. The latter, however, may be slowly pulled apart in the course of marked ring dilatation. Bicornate lesions and sclerotic lipping in the mid-portion of the free margins of the leaflets are characteristic of this type of regurgitation. Syphilis may coexist in some cases; it may cause aortitis without involving the aortic valvular structure. Occasionally there may be both ring dilatation (“mechanical” insufficiency) and true syphilitic aortic valvular disease.