RESIDENT PHYSICIAN ATTITUDES TOWARD ANTICOAGULATION FOR STROKE PREVENTION IN PATIENTS WITH NONVALVULAR ATRIAL FIBRILLATION

BACKGROUND: Atrial fibrillation (AF) is the most common cardiac arrhythmia. It is associated with an increased risk of ischemic strokes. Stroke prevention is the mainstay of management. Novel oral anticoagulants (NOACs) are part of the current therapeutic arsenal and resident physicians should be familiar with their use. The aim of this study was to identify practice patterns of Canadian resident physicians with respect to stroke prevention in patients with nonvalvular AF. METHODS: This was a cross-sectional survey, inviting internal, family, emergency medicine and adult cardiology residents from 8 academic centres across Canada. A web-based survey consisting of 13 multiple-choice questions was distributed. Questions focused on identifying risks of stroke and bleeding and selecting appropriate therapy in clinical scenarios involving patients with CHADS2 scores of 3. RESULTS: There were 704 respondents, of which 393 were internal, 196 family, 84 emergency medicine, and 31 adult cardiology residents. When determining the risk of stroke, 85% used CHADS2 and 70% used CHA2DS2-VASc scores. Assessment of bleeding risk was determined using theHAS-BLED score by 82% and 43% used clinical impression as an adjunct. When recommending one or more agents for a patient with no contraindications to anticoagulation, warfarin was chosen by 83% followed by rivaroxaban (55%), dabigatran (51%) and apixaban (48%). In a patient who had a history of gastrointestinal bleeding on acetylsalicylic acid (ASA) 1 year prior, 76% recommended warfarin, 34% apixaban, 29% rivaroxaban, 23% dabigatran and 13% ASA. For a patient on warfarin with labile INRs, 31% continued warfarin and provided more education, while 52% switched to a NOAC.When deciding on who should prescribe anticoagulation for a patient with a new diagnosis of AF in the emergency department, 46% chose family doctor, 32% emergency physician and 13%would consult internal medicine. If a reversal agent were to become available for theNOACs, 64% indicated theywould no longer prescribe warfarin for stroke prevention in most patients. CONCLUSION: This study revealed that, across a wide sampling of disciplines and centres, resident physician attitudes toward anticoagulation in patients with nonvalvular AF differ significantly from the current Canadian Cardiovascular Society guidelines. Lack of familiarity, fear of adverse events and absence of a reversal agent were identified as potential barriers to the use of NOACs. This study highlights the need for further education of Canadian resident physicians in the use of anticoagulants for stroke prevention in patients with nonvalvular AF.