RESUMO
BACKGROUND: Thrombosis of mechanical prosthetic heart valves (TMPHV) is one of the major complications that accounts for the highest morbidity and mortality related to Bileaflet Mechanical Prosthetic Heart Valves (BMPHV). MATERIALS AND METHODS: During the last six years we had ten cases of bileaflet mechanical valve thrombosis. All patients had undergone emergency surgical interventions except one who developed systemic embolization and massive brain insult immediately after admission for surgery and died two months later. We divided the patients in two groups, first group includes five patients who came in acute pulmonary edema and emergency operation was done either to replace the thrombosed BMPHV (in two) or successful thrombectomy was achieved (in three) and all of them have survived. The second group (four patients) presented with cardiogenic shock and required emergency femoro-femoral bypass. Two patients survived after thrombectomy and the other two could not come off bypass after changing the TMPHV and in spite of Intra-aortic balloon pump, they died 24 and 48 hours after the procedure. All patients received intravenous heparin on admission. Preoperative i.v. Streptokinase was given in two cases, of which one required thrombectomy and the other had valve replacement and died 24 hours later. RESULTS: Early diagnosis and operation still had the best results in TMPHV though thrombolytic therapy was successful in few reported early presented cases. All patients who had thrombectomy of the TMPHV have survived without any morbidity. Follow up of survived patients ranged between two months and six years with a mean of 24.1 months. It is worth attempting thrombectomy of the thrombosed BMPHV rather than re-replacement which carries higher morbidity and mortality, because of the longer ischemic arrest during operation which further depletes the energy of the myocardium. CONCLUSIONS: Though this is a small number of patients to make a definite conclusion, thrombectomy was more feasible in CarboMedics Prosthetic Heart Valves, since its in situ rotation that allows reorientation of its leaflets and declotting of valve hinge to be performed.
