Anticoagulation use in the setting of atrial fibrillation in a typical outpatient cardiology population

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background The risk of cerebrovascular events has been greatly reduced with the guideline recommendation of anticoagulation in the presence of atrial fibrillation (AF). Based on current epidemiological evidence, over ⅓ of patients with known AF who are eligible for anticoagulation, do not receive them. The elderly population are especially susceptible to this disparity. The CHA2DS2-VASC score is currently being used to assess for need for anticoagulation in patients with AF. More recently, the HAS-BLED score has been developed to assess for bleeding risk. Weighing the bleeding risk using HAS-BLED score with stroke risk using CHA2DS2-VASC score, we assessed if a segment of the Canadian population with AF were appropriately anti-coagulated. Purpose Assess the concordance of one outpatient cardiology practice with anticoagulation guidelines for atrial fibrillation. Materials & Methods Patients were randomly selected from a single centre outpatient Cardiology practice between January and May 2021. The patients were selected by 1 researcher. The patients selected must have been diagnosed with atrial fibrillation by ECG and Holter analysis. The HAS-BLED and CHA2DS2-VASC scores were calculated for each individual. Results 101 patients were selected for this study. 66 were male and 35 were female with ages ranging from 33 to 91 years old. Patients with a CHA2DS2-VASC score greater than 1, were anti-coagulated with direct oral anticoagulation (DOAC) unless they were in severe renal failure (creatinine clearance <30ml/min) in which case Warfarin was used. In the age group of 65 and under, 12 patients had a CHA2DS2-VASC score greater than 1 and were anti-coagulated. In the age group 65 and over, 72 had a CHA2DS2-VASC score greater than 1. Of the 72 individuals, 71 were appropriately anti-coagulated. In the age group 80 and over, 29 individuals had a CHA2DS2-VASC score greater than 1 and were anti-coagulated. For the individuals on anticoagulants, the HAS-BLED score was less than or equal to the CHA2DS2-VASC score. Only one of the patients in the study with a CHA2DS2-VASC score greater than 1, was not anti-coagulated. There were no reported major bleeding risks in the patients reviewed. Conclusion In a sample of the typical Canadian population, based on risk factor assessments using both the CHA2DS2-VASC and HAS-BLED scores, 99% of patients were appropriately anti-coagulated in the presence of AF. This shows a significant increase in appropriate management of AF patients compared to the current national and global averages. There were no major bleeding events reported in any of the patients receiving full anticoagulation. This supports the recommendation that the benefit of anticoagulation in stroke reduction from thromboembolism outweighs the risk of major bleeding events.