Resident Physicians Choices of Anticoagulation for Stroke Prevention in Patients With Nonvalvular Atrial Fibrillation

Atrial fibrillation (AF) is a common cardiac arrhythmia and is associated with an increased risk of ischemic stroke. The aim of this study was to identify practice patterns of Canadian resident physicians pertaining to stroke prevention in nonvalvular AF according to the Canadian Cardiovascular Society guidelines. A Web-based survey consisting of 16 multiple-choice questions was distributed to 11 academic centres. Questions involved identification of risks of stroke, bleeding, and selection of appropriate therapy in clinical scenarios that involve a patient with AF with a Congestive Heart Failure, Hypertension, Age, Diabetes, Stroke/Transient Ischemic Attack (CHADS2) score of 3 and no absolute contraindications to anticoagulation. There were 1014 total respondents, of whom 570 were internal, 247 family, 137 emergency medicine, and 60 adult cardiology residents. For a patient with a new diagnosis of AF, warfarin was chosen by 80.3%, novel oral anticoagulants (NOACs) by 60.3%, and acetylsalicylic acid (ASA) by 7.2% of residents. To a patient with a history of gastrointestinal bleed during ASA treatment, warfarin was recommended by 75.1%, NOACs by 36.1%, ASA by 12.1%, and 4% were unsure. For a patient with a history of an intracranial bleed, warfarin was recommended by 38.8%, NOACs by 23%, ASA by 24.8%, and 18.2% were unsure. For a patient taking warfarin who had a labile international normalized ratio, 89% would switch to a NOAC and 29.5% would continue warfarin. This study revealed that, across a wide sampling of disciplines and centres, resident physician choices of anticoagulation in nonvalvular AF differ significantly from contemporary Canadian Cardiovascular Society guidelines.