47 Anticoagulation variability as a predictor of bleeding in patients with mechanical heart valves

Abstract

Background Patients with mechanical heart valves require life-long anticoagulation with warfarin. Variability of anticoagulation is a major concern in such patients. Previously, we found that mechanical heart valve patients spent only 66% of their time within the therapeutic range (TTR). However, there is currently little data relating quality of anticoagulation to bleeding risk in patients with mechanical heart valve prostheses. Methods This was a cross-sectional study of patients attending a Nurse-Led Heart Valve Anticoagulation Clinic. Data analyzed included patient demographics, comorbidities, and concurrent drug therapy to calculate HAS-BLED and ATRIA scores. International normalized ratio (INR) values were used to calculate time spent in the therapeutic range (TTR) by the Rosendaal Method. The relationship between variables was analyzed using linear correlation (Spearman Rho) and logistic regression as deemed appropriate. Data were analyzed using SPSS (SPSS for Windows), with p Results The study cohort consisted of 260 patients with a mean age of 54±15 years. The mean TTR was 66+16%. 27 (10%) patients had HAS-BLED scores of more than 3 (high risk). Bleeding (cerebral, gastrointestinal, or hemoglobin Conclusion Similar to previous reports of patients with atrial fibrillation, ATRIA and HAS-BLED scores were the best predictors of bleeding in our cohort of patients with mechanical heart valves, with no independent contribution of TTR to estimation of bleeding risk.