Predictive factors for obtaining a correct therapeutic range using antivitamins K: a tertiary centerexperience

Introduction: Patient adherence is an essential factor in obtaining an effi cient oral anticoagulation using antivitamin K drugs (AVK), a situation with a narrow therapeutic window. Therefore patient education and awareness are crucial for a good management. Auditing the current situation helps to understand the magnitude of the problem and to build tailored education programs for these patients. Methods: This study included 67 hospitalized chronically anticoagulated patients (pts) (mean age: 62.6 ± 13.1 years; men 45.6%) who responded to a 25-item questionnaire to assess their knowledge on AVK therapy management. Laboratory and clinical data were used to determine INR value at admission, as well as to calculate CHADS2-VASC and HAS-BLED scores for patients with atrial fi brillation (AF). Results: The majority of pts (61.8%) were receiving AVK for AF, the others having a mechanical prosthesis and previous thromboembolic disease or stroke. In the AF group, the mean CHADS2-VASC score was 3.1 ± 1.5, while average HAS-BLED score was 1.8 ± 1.2. More than half of all pts (52.9%) had at admission an INR outside of the therapeutic range, with the majority (42.1%) having a low INR. A correct INR value was predicted by the education level (higher education), the diagnostic indication (pts with mechanical prosthesis), and the concomitant use of other antithrombotic therapies. Pts presenting with a therapeutic INR had a trend towards longer treatment duration than those outside the therapeutic range (62 ± 72 vs 36 ± 35 months, p = 0.06). Conclusions: In a tertiary cardiology center, more than half pts receiving AVK are admitted with an INR falling outside the therapeutic range, irrespective of the bleeding or embolic risk. Pts with mechanic prosthesis and complex antithrombotic regimens appear as most careful with INR monitoring, especially if having higher education. Identifying pts groups with lowest therapeutic range rate could help attending physicians educate pts focusing on specifi c awareness issues.

ISSN – online: 2734 – 6382
ISSN-L 1220-658X
ISSN – print: 1220-658X
The Romanian Journal of Cardiology is indexed by:
ESC search engine
CODE: 379
CME Credits: 10 (Romanian College of Physicians)