Optimal Oral Anticoagulation Therapy and Major Bleeding in Patients with Heart Diseases in a Peruvian Heart Institute

Abstract number: P2328

Cotrina R, Villar A

Introduction:  Use of warfarin in cardioembolic events prevention is a common practice in patients with heart diseases, being the greatest difficulties to keep therapeutic anticoagulant level and prevent major bleeding. In order to determine the prevalence of adequate anticoagulation and major bleeding during the treatment with Warfarin, we carried out this descriptive, transversal study during 2004.

Methods and patients:  We got the sample over a population of 1200 users of warfarin because of cardiac diseases, with an error tolerance 5% and a confidence level of 99%. We applied a questionnaire, measured blood pressure and took blood samples for INR, the risks and variables were defined according to the ACC/AHA and ACCP.

Results:  There were included 216 patients, 58.8% with prosthetic heart valves and 38.4% with atrial fibrillation, it was found optimal anticoagulant effect in 47.7%, 52.2% y 52.3% on the day of the study, 3 and 6 months before respectively. The 38.4, 28.3 y 33.5% of patients were poorly anticoagulated respectively; 12% had no anticoagulant effect at the time of control; 11.1% and 6.0% had cardioembolic stroke and a major bleeding respectively sometime during oral anticoagulation. The risk of major bleeding were age >65 years (44.9%), arterial hypertension (41.2%) and INR >3.5 (13.9%).

Conclusions:  (1) In our Peruvian heart Institute, only 50% of patients have kept optimal anticoagulant effect during their follow-up; 12% have not kept any anticoagulant effect at any moment and have suffered from stroke. Highly-prevalent risk factors for major bleeding were, age >65 years old and arterial hypertension, INR >3.5 was less frequent but of greater importance for major bleeding. (2) In order to guarantee the prevention of cardioembolic events in cardiac patients it is necessary an anticoagulant drug for chronic use with predictable anticoagulant effect, which does not interfere with drugs or food and which does not require laboratory monitoring.