Warfarin and atrial fibrillation: from ideal to real the warfarin affaire

Abstract

Vitamin K Antagonists (VKAs) are widely used in clinical practice and nearly 1% of the entire population receives oral anticoagulation at least once in life. However, the rate of prescription of anticoagulation is low, compared to what it should be. No more than 50-60% of patients affected by atrial fibrillation (AF) receive anticoagulation. In the setting of AF, VKAs are safe and effective when properly managed, reducing stroke and systemic embolism by more than 60%. VKAs safety and effectiveness are closely related to the quality of anticoagulation (e.g. time in therapeutic range), and anticoagulation clinics offer the best management of anticoagulant therapy. However, a sizeable proportion of patients are managed elsewhere. In clinical practice, in the setting of AF, a low prescription rate of VKAs is frequently observed and this is due also to difficulties in managing laboratory monitoring and drug dose adjustment. The suboptimal management of therapy with VKAs leads to a lesser efficacy than that reported in clinical trials, and to an increase in adverse reactions. VKAs still remain the first and only available therapy for a number of diseases (e.g. valvular atrial fibrillation and mechanical prosthetic heart valves). Now, since approval of the new oral anticoagulants (NOAs), the choice of anticoagulant therapy in definite settings, such as stroke prevention in non-valvular atrial fibrillation (SPAF) or treatment of venous thromboembolism, has surely become more intriguing but also more problematic. In light of these new therapeutic options, we reviewed VKAs therapy, in the setting of atrial fibrillation, focusing on VKAs impact in real life. We analyzed the data about efficacy and safety of warfarin at three levels: clinical trial and real life, outside and inside anticoagulation clinics.

Evaluation of the impact of warfarin time in therapeutic range on outcomes of patients with atrial fibrillation in Turkey: Perspectives from the observational, prospective WATER Registry

“…Lower TTR values in real life patients rather than randomized controlled trial patients have been confirmed consistently throughout different countries [8,9]. Data on AF epidemiology and management in Turkey are quite limited and prospective mild-to long-term studies are lacking.…”

The Impact of Ischemic Stroke on Atrial Fibrillation-Related Healthcare Cost: A Systematic Review

“…It is estimated that 10-30% of AF are not diagnosed 32,35 and more than 40% of patients at high risk of stroke fail to receive guideline-recommended oral anticoagulant treatment 11,35 . 39 and increased risk of stroke 40,41 . All these gaps highlight unmet needs for stroke prevention in undiagnosed and undertreated AF, which will shed light on the strategies needed to eliminate disparities in treatment.…”

Quality of anticoagulation among patients with nonvalvular atrial fibrillation in the Primary health care center 'Novi Beograd'

“…Квалитет антикоагулантне терапије пацијената са атријалном фибрилацијом у Дому здравља ''Нови Београд'' Општа медицина 2017;23 (3)(4):59-66…”

“…Израчунавањем CHA 2 DS 2 -VASc скора издвајамо па-цијенте са малим ризиком за мождани удар (мушкарци са скором 0 и жене са скором 0-1) код којих није индико-вана тромбопрофилакса, док су сви остали кандидати за примену оралне антикоагулантне терапије (АКТ)³. Адек-ватна орална антикоагулантна терапија смањује ризик од можданог удара за 65% и морталитет за 26% и далеко је ефикаснија од примене само аспирина (>50%) или двој-не антиагрегационе терапије (>30%) 4 . Прва терапијска линија у превенцији шлога код па-цијената са АФ јесу антагонисти витамина К (VKA).…”