Anticoagulation Therapy in Patients with Atrial Fibrillation in Ambulatory Consultant Cardiology Clinics after Availability of New Oral Anticoagulants

Introduction: Anticoagulation is effective therapy in AF patients for stroke prevention: vitamin K antagonists were the only used anticoagulant agents till New Oral Anticoagulants (NOACs) began to be available in clinical practice.
We investigated the utilization of NOACs in AF patients in ambulatory consultant cardiology clinics.

Patients and Methods: We studied consecutive patients with documented diagnosis of AF sent to our cardiology clinics over a 4 months period. The recorded information included demography, co morbidities, prescribed drugs, CHADS₂, CHA₂DS₂-VASc₂, HAS-BLED scores.
National health law provides general health coverage to all Israeli citizens. NOACs therapy for non rheumatic AF is covered for the following indications: CHADS₂ score ≥3; CVA or TIA in patients treated by warfarin; unstable INR on warfarin.

Results: Two hundred forty six patients with non valvular rheumatic AF were our study population. Hypertension was the most frequent co morbidity (77.6%), followed by diabetes mellitus (37%). β-Blockers (75.3%), Ace Inhibitors (63%) and Statins were the most frequent prescribed drugs.
In patients with CHADS₂ score 2 score ≥3 Warfarin and NOACs were used in 23 (23%) and 72 (72%) patients respectively (p= 0.00001) 32 patients (13%) did not received anticoagulant therapy: 15 patients (6.1%) according to ESC guidelines (3 patients received aspirin); 9 patients (3.7%) refused anticoagulants and agreed only to aspirin therapy; 8 patients (3.2%) refused both kind of therapies; 7 patients (2.8%) received Warfarin with aspirin.

NOACs were given at low dose in 69 patients (65.7%) and at the standard dose 36 patients (34.3%).

Conclusions: The use of NOACs is limited by insurance coverage restriction. In daily clinical practice the use of NOACs at a lower dose is more frequent than the lower NOACs dose used in the Trials.