[Transitory left ventricular outflow tract obstruction after mitral valve reconstruction]. / Passagere Obstruktion des linksventrikulären Ausflusstraktes nach Mitralklappenrekonstruktion.

ABSTRACT

HISTORY AND ADMISSION FINDINGS: A few days after uneventful surgical reconstruction of the mitral valve a 43-year-old man was found to have a systolic murmur due to prolapse of the posterior leaflet, suggesting renewed mitral regurgitation. INVESTIGATIONS Echocardiography revealed haemodynamically significant left ventricular outflow tract obstruction (LVOT) with a left ventricle to aorta systolic gradient of 83 mm Hg. In addition there was moderately severe mitral regurgitation as well as a pericardial effusion but no signs of tamponade. TREATMENT AND COURSE The obstruction was at first treated with verapamil, later with sotalol. The pericardial effusion was interpreted as part of a postcardiotomy syndrome. The effusion regressed under steroid administration, and the LVOT and mitral regurgitation also decreased. A provocation test five months postoperatively no longer brought about an outflow gradient. The good results were still present 12 months postoperatively. CONCLUSION: The described, rarely seen form of LVOT was probably caused by a combination of a very large anterior mitral leaflet, postoperative pericardial effusion and pharmacological effects. If the obstruction first occurs postoperatively, appropriate medication may improve the cardiac status and reoperation may be avoided. Echocardiography is an important method of diagnosis and serial monitoring.