Single-center Experience of Slow Thrombolysis in Stuck Mechanical Mitral Valve in India

Abstract

ABSTRACT Introduction: India is the rheumatic heart disease (RHD) capital of the world. It is home to 40% of all people of RHD. Many of these patients undergo valve replacement surgeries in our country. These patients present with prosthetic heart valve thrombosis (PHVT) as the international normalized ratio (INR) is not monitored due to several restraints. Many precious lives are lost due to the scarcity of cardiac surgery centers and the high mortality associated with redo procedures. Various international studies have proved the efficacy and low complication rate of slow thrombolysis with tissue plasminogen activator (tPA) compared to surgery in PHVT. Most Indian studies have used streptokinase for PHVT and data on tPA are lacking. Materials and Methods: Twenty-one patients with prosthetic mechanical mitral valve presenting with dyspnea, a high gradient across the prosthetic valve, and decreased leaflet motion were included in the study. As it is not always possible to differentiate pannus from a thrombus and association of some degree of thrombosis even in pannus, we offered thrombolysis as the first line of treatment to all patients. Slow thrombolysis with 25 mg of tPA over 6 h followed by unfractionated heparin for 18 h was given, and thereafter, patients were reassessed for thrombolytic success or complications if any. A total four sessions of thrombolysis were given, and thereafter, patients with failed thrombolysis were referred for valve replacement surgery. Results: Out of 21 patients, 67% were females. The mean age of patients was 54.33 ± 10.6 years. Fifty-seven percent of patients were in the New York Heart Association (NYHA) III/IV. Atrial fibrillation was present in 62% of patients. The mean time of interval from the time of valve surgery to the time of thrombosis was 80 ± 57 months and the mean INR was 1.43 ± 0.4. The total success rate was 71% in this study, 9% had complications, and 19% had failed thrombolysis and underwent redo mitral valve replacement. The mean dose of tPA was 56.58 mg in this study and a mortality rate of 4%. Age had no effect on the success of thrombolysis. The presence of sinus rhythm, NYHA class I/II status, EF more than 40%, and mean gradient <20 mmHg was associated with a higher likelihood of success. Conclusion: In this study of PHVT in Indian patients, slow (6 h) infusion of low-dose (25 mg) tPA proves to be associated with a low complication rate, low mortality, and a promising success rate. This regimen can be offered to PHVT patients in our peripheral centers where cardiac surgical facilities are not readily available.