Surgery Versus Fibrinolytic Therapy for Left-sided Prosthetic Heart Valve Thrombosis

Malfunction of mechanical heart valves due to clot formation is a potentially devastating complication. It often results in heart failure, death or stroke. This condition occurs frequently in patients with mechanical valves in developing countries because they are unable to monitor and adjust the dose of blood thinning medications. The best treatment modality for the treatment of patients with this condition is not known. There is no reliable data from clinical trials to guide treatment and there are no firm guidelines. Treatment with clot-busting drugs is most commonly used because these drugs (e.g., streptokinase) are readily available, cheap, and easy to use. However, this treatment is associated with high rates of treatment-related side-effects (death, life-threatening bleeding and stroke). Moreover, some recent studies suggest that clot-busting drugs may not be as efficacious in restoring valve function, as previously believed. Emergency surgery is less often used because it is more expensive and the required facilities and manpower are not available at all times at all places. But there is evidence to suggest that surgery results in better success rates with a lower risk of bleeding and stroke. Well-designed prospective randomised trials (the "gold-standard" for reliable evidence) comparing the efficacy, safety and cost-effectiveness of the two modalities, are needed to help doctors in developing countries make informed decisions when treating patients with clotted mechanical heart valves. The investigators propose to perform a randomised controlled trial comparing emergency surgery with treatment with clot-busting agents in patients with clotted mechanical valves. The study will be conducted over 4 years at a single, university hospital in a developing country. This study will determine how often patients who are treated with surgery will be discharged from hospital, with completely restored valve function, without having suffered a stroke or life-threatening