Tomography of calcified aortic and mitral valves.

The purpose of this paper is to compare the value offluoroscopy and tomography in distinguishing aortic from mitral valve calcification. In view of this difficulty, certain criteria are recorded to aid their identification. Aortic valve calcification was first described in 1672 by Rayger (quoted by Bonetus, 1679). Eighty-two years later, Morgagni recorded a patient dying in cardiac failure who had a bony aortic valve. Single patients with both aortic and mitral valve calcification at necropsy were reported by Turner (1885) and Weber (1898). But not until the last twenty-five years have reports of aortic valve calcification been common and only since then has the condition been recognized in life (Christian, 1931; Sparks and Evans, 1934; Blackford et al., 1936; Berk and Dinnerstein, 1938). In 1933, Sosman and Wosika described the fluoroscopic recognition of mitral and aortic valve calcification. Further reports by Sosman appeared in 1939 and 1943. Tomography was first applied to the detection of aortic valve calcification by Davies and Steiner (1949) who recorded fourteen such patients: they found it to be more successful than fluoroscopy. Daley (1957), however, stated that fluoroscopy was more reliable than tomography for showing aortic valve calcification, but thought that the image intensifier was best. Simon (1956) thought that in centres where the image intensifier was not available, there was still a place for tomography of the heart valves. With the advent ofvalvotomy, the detection of calcification became important because its presence was soon found to affect the outlook for success. Both Baker et al. (1952) and Wood (1954) found that gross calcification of the mitral valve, especially when associated with mitral regurgitation, made a successful valvotomy unlikely. Even if regurgitation is not initially present, valvotomy may lead to this when the valve is calcified (Wood, 1954). Although Turner and Fraser (1956) agreed that calcification may make valvotomy difficult or even impossible, they found good results in more than half their patients. They confirmed Wynn's findings that heavy calcification of the mitral valve altered the mitral rhythm of Duroziez (1862) and thought fluoroscopy better than tomography for showing calcification. Campbell and Kauntze (1953) thought that calcification was nearly always present in congenital aortic stenosis after forty years of age and favoured stenosis of the valve rather than the subaortic region. Brock agreed (1957a) and thought it important that when there is calcification its site should be determined and recorded permanently (1957b).