Systolic anterior motion of the mitral valve after Carpentier ring valvuloplasty for mitral valve prolapse.

Between July 1983 and March 1985, 45 patients with severe mitral regurgitation underwent mitral valvuloplasty with insertion of a semirigid Carpentier ring. No patient had echocardiographic evidence of systolic anterior motion (SAM) preoperatively, whereas 5 patients had this echocardiographic finding postoperatively. All 5 had mitral valve prolapse as their underlying disease process and SAM developed at varying intervals after valvuloplasty. The development of SAM is related to insertion of the semirigid ring, persistence of a redundant anterior mitral leaflet, narrowing of the left ventricular (LV) outflow tract and the Venturi effect. LV and aortic pressure measurements with simultaneous Doppler echocardiography have confirmed the presence of a significant LV outflow tract gradient in these patients. Although all 5 patients are functionally improved after mitral valvuloplasty, the long-term implications of SAM after valvuloplasty are unknown.