The echocardiographic features were recorded in three patients with spontaneous disruption of implanted tissue aortic valves. Two of the patients had xenografts, and one had a homograft. Aortic regurgitation had developed in all three spontaneously in the absence of active infective endocarditis. In each case there was severe disruption of the valve. Similar echocardiographic features have been found, usually in association with infective endocarditis or with myxomatous degeneration of the aortic valve. They have not previously been reported in association with implanted tissue aortic valves.