[Left ventricular outflow tract obstruction after mitral valve plasty; report of a case].

: A 65-year-old female was admitted to our hospital with mitral regurgitation (MR). Transthoracic echocardiography showed severe mitral valve prolapse and subaortic septal hypertrophy with no pressure gradient. Mitral valve plasty consisted of artificial chorda implantation and ring annuloplasty was performed. During intensive care unit( ICU) stay after operation, systolic murmur and low cardiac output syndrome were noted and echocardiography revealed left ventricular outflow tract obstruction (LVOTO) without systolic anterior motion and MR. Cessation of catecholamine, volume administration, beta-blocker and negative inotropic drug like cibenzoline rapidly reduced LVOTO and the hemodynamic condition was improved. Even in a case of subaortic septal hypertrophy with no pressure gradient, emergence of LVOTO should be considered when new systolic murmur and low cardiac output syndrome appeared.