Two Monitoring Methods of Oral Anticoagulant Therapy in Patients with Mechanical Heart Valve Prothesis: a Meta-analysis

Oral anticoagulant therapy (OAT) with warfarin has become the standard therapy for the patients with mechanical heart valve prothesis. The monitoring method of self-monitoring or self-management was promising to optimize the use of warfarin, but most of previous studies have included patients with various indications of OAT, which made it difficult to extrapolate the results to the specific patient population with mechanical heart valve prostheses. This study was intended to evaluate the new and traditional monitoring methods in patients with mechanical heart valve prostheses. Relevant literature finished before Dec. 2010 were searched through a number of digital databases. And then they were pooled by RevMan 4.2 and R 2.13.0 in three fields: rate within the target range, test frequency and occurrence rate of poor events. Five randomized control trials with a total of 2,219 patients were identified. Pooled estimates showed reductions in thromboembolic events (OR 0.52, 95% CI 0.35-0.77; P = 0.0012) and all-cause mortality (OR 0.50, 95% CI 0.29-0.86; P = 0.0115). No difference was noted in major and minor haemorrhage. All trials reported improvements in the mean proportion of international normalized ratios in range. Self-monitoring and self-management can improve the quality of OAT in the patients with mechanical heart valve prostheses. The patients spend more time within the therapeutic range resulting in decreases in thromboembolic events and mortality, with no increase in haemorrhage. However, self-monitoring and self-management was not feasible for all patients, and require identification and education of suitable candidates. The success of self-monitoring and self-management method depends on consistent, regular, and frequent testing.