[Paroxysmal mitral insufficiency caused by ischemic dysfunction of the papillary muscles. Hemodynamic and angiographic study of 18 cases. Pathogenic hypotheses].

18 of 39 cases of ischaemic papillary muscle dysfunction reported elsewhere underwent cardiac catheterisation and angiography. Fifteen patients had previous myocardial infarction. The average age of the patients was less than in the overall series (69 vs 73 years) but the incidence of infarction and the degree of cardiac disease were greater. The absence of catheter data in the other patients is explained by their older age (76.4 years) and the longer period of recruitment. Their results and outcome of medical or surgical treatment are reported. The pathogenesis of the syndrome is reconsidered in the perspective of paroxysmal forms. A protocol for investigation is suggested to guide the therapeutic options. Right heart catheterisation at rest (n = 16), on exercise (n = 12), under vasodilator therapy (n = 6) and during angiography (n = 2) does not show a specific profile. These investigations only provide haemodynamic data related to therapy but they are essential for the interpretation of ventriculography. Ventriculography (n = 8) demonstrated 4 cases of mitral regurgitation (2 major and 2 minor), a reduced EF (0.47 +/- 0.17), asynergy of 36.1 p. 100 of segments analysed, predominantly in the inferior and lateral zones. Coronary angiography showed triple vessel disease in 6 cases, double vessel disease in 1 case and 1 stenosis of the left main coronary artery. Stenosis was commonest on the left circumflex (87.5 p. 100) and right coronary arteries (87.5 p. 100) but also frequently involved the left anterior descending artery (75 p. 100). Of the 12 patients treated medically, 8 died (66.6 p. 100) and the survivors remain symptomatic (33.3 p. 100), half with and half without attacks. After surgery (n = 8) comprising coronary bypass surgery (n = 6) or mitral valve replacement (n = 2), patients were asymptomatic. 1 patient died of cancer. These paroxysmal forms of mitral regurgitation may be explained by the association of aggravating, reversible ischaemic or haemodynamic factors to organic mitral lesions. Mitral valve replacement is justified when dysfunction becomes permanent and coronary bypass surgery is advocated whenever possible. The indications for surgery can only be taken into account after complete haemodynamic and angiographic investigation. A protocol for the interpretation of these investigations is suggested.