Postoperative Strokes and Intracranial Bleeds in Patients With Atrial Fibrillation: The FibStroke Study.

BACKGROUND: Patients with atrial fibrillation (AF) frequently undergo invasive procedures. Optimal perioperative use of oral anticoagulation (OAC) and heparin bridging is not well defined. HYPOTHESIS: Discontinuation of OAC for minor procedures/operations places AF patients at risk for thromboembolism. METHODS: In this study, we assessed perioperative antithrombotic treatment in patients with AF who suffered a postoperative stroke or intracranial bleeding. The FibStroke Study includes AF patients with an ischemic stroke or intracranial bleed identified from the discharge registries of 4 Finnish hospitals. In total, 3632 consecutive patients developed 3252 ischemic strokes and 794 intracranial bleeds. All invasive procedures during the 30 days preceding the stroke or intracranial bleed were identified. RESULTS: A total of 194/3252 (6.0%) ischemic strokes and 23/794 (2.9%) intracranial bleeds were preceded by a procedure. Altogether, 69% of the patients were on OAC prior to index procedure, OAC was interrupted in 81.2% of the procedures preceding a stroke, and heparin bridging was used in 27.8% of interruptions. Of the procedures leading to stroke, 42.3% were low-bleeding-risk procedures, and OAC was interrupted in 84.7% of these procedures. The median time from procedure to stroke was 4 days. Heparin bridging was used in 54.5% of OAC interruptions preceding intracranial bleeding and combination of anticoagulation with antiplatelet therapy by 43.5% of patients with postoperative intracranial bleeding. CONCLUSIONS: Perioperative interruption of OAC is common in patients who suffer a postoperative stroke, even in patients with low-bleeding-risk procedures. Postoperative intracranial bleeding is frequently preceded by perioperative heparin bridging.

Strokes after cardioversion of atrial fibrillation--The FibStroke study.

BACKGROUND: Cardioversion of atrial fibrillation (AF) is associated with an increased risk for stroke. We identified all cardioversions during the 30 days preceding stroke or transient ischemic attack (TIA) in patients with a previously diagnosed AF, and sought to assess the characteristics of cardioversions leading to stroke or TIA. METHODS: FibStroke is a cross-sectional observational multicenter registry that included AF patients with an ischemic stroke or intracranial bleed identified from a discharge registry of four Finnish hospitals. In total 3677 consecutive AF patients suffered 3252 strokes and 956 TIA episodes during 2003­2012. This pre-specified analysis focused on the 1644 events that occurred to patients with paroxysmal or persistent AF at the time of stroke/TIA. RESULTS: A total of 78 strokes and 22 TIA episodes were preceded by a cardioversion. Post-cardioversion strokes accounted for 6.4% of strokes in patients with paroxysmal/persistent AF. Of the 100 cardioversions leading to an ischemic event, 77 were acute and 23 were elective, 63 events occurred in patients not using anticoagulation, and 5 patients had periprocedural INR < 2. Importantly, 21 patients were in low risk of stroke, i.e. CHA2DS2-VASc score < 2. The median delay from cardioversion to event was 2 days. All nine patients who after an unsuccessful cardioversion developed a stroke had a spontaneous cardioversion prior to stroke. CONCLUSIONS: Every sixteenth stroke of patients with paroxysmal/persistent AF is preceded by a cardioversion. Most post-cardioversion strokes occur in patients not using oral anticoagulation before cardioversion of acute AF.