Assessment of the warfarin anticoagulation knowledge of patients with mechanical mitral valve prosthesis and its effect on therapy adherence and relevant complications

Introduction
The mechanical valves that are commonly used in replacement surgery pose risks of thromboembolic events. Thus, anticoagulation after surgery is essential. Warfarin is a widely used anticoagulant with a narrow therapeutic index and major side effects. This study aimed to assess the warfarin knowledge of patients with mechanical mitral valves and its effect on adherence and complications. This study aimed to assess the warfarin knowledge of patients with mechanical mitral valves and its effect on adherence and complications.

Material and methods
This cross-sectional study was conducted on a group of 168 patients, with a mean age of 61.76 ± 9.35 years, predominantly consisting of females. The patients were visited at their homes and interviewed directly using a self-developed questionnaire that assessed the profile and knowledge of the patients on warfarin anticoagulation and relevant side effects.

Results
The results demonstrated a poor level of knowledge among the patients, although they received medical information. The statistical analyses revealed a significant association between the medical knowledge provided and increased international normalised ratio (INR ) knowledge and adherence to prescriptions and follow-ups. The rates of complications were found to be significantly higher in patients who did not have knowledge about INR and who did not adhere to follow-up visits.

Conclusions
We identified a critical gap in the knowledge of patients about warfarin therapy. The significant association between the lower rates of complications and medical knowledge is promising. We suggest that the current study be extended onto larger and more focused research to develop standardised tools to educate patients on anticoagulation.