Surgery for prosthetic valve obstruction. A single center study of 136 patients.

OBJECTIVES Prosthetic heart valve obstruction (PHVO) is a potentially fatal complication of heart valve replacement with mechanical substitute mainly due to thrombosis. The purpose of this report is to present a single-center experience of 136 consecutive patients operated on between 1978 and 2001. METHODS The diagnosis of PHVO was mainly assessed by fluoroscopy and/or echocardiography. Thrombosed valves were bileaflet (82), tilting disc (47) and ball cage (7) valves; of these, 90 were in mitral, 38 in aortic, six in aortic and mitral position, and two in tricuspid position. The mean interval between the first implantation and valve thrombosis was 7.4+/-6.6 years (range 1 day to 28 years); in 37 patients preoperative medical therapy (fibrinolysis in 21, and heparin alone in 16) was unsuccessful. RESULTS Operative procedures included valve re-replacement in 104 cases and declotting-pannus excision in 32 cases. Early hospital mortality was 10.3% (14 patients), all in NYHA class III or IV, and one patient suffered a perioperative cerebral embolic event. Surgery was then successful in 121 of 136 patients (89%), but during a 3.15-year follow-up, prosthetic heart valve thrombosis recurred in ten out of 122 survivors (8.1%). CONCLUSION From this experience, it can be concluded that for most PHVO, early operation is currently effective and safe, especially in patients in stable hemodynamic condition preoperatively.