Temporal Trends in Pharmacological Stroke Prevention in Patients with Acute Ischemic Stroke and Known Atrial Fibrillation.

INTRODUCTION: Oral anticoagulation (OAC) substantially reduces stroke risk in patients with atrial fibrillation (AF) at risk for stroke. Whether non-vitamin K-dependent oral anticoagulants (NOACs) improve OAC use in stroke prevention requires investigation. METHODS: To investigate temporal trends of OAC use in patients with known AF pre-stroke, we retrospectively analyzed records of 6,803 stroke patients admitted in 2003-2004 (n=1,496), 2008-2010 (n=1,638) or 2013-2015 (n=3,669) to the Charité-Universitätsmedizin Berlin, Germany. Adjusted regression models were used to identify factors associated with OAC use. RESULTS: Of 1,209 AF patients (mean age 79 years, 55.9% female) with given indication for OAC according to the CHADS2/CHA2DS2-VASc score, 484 (40.0%) were anticoagulated prior to the index stroke, 458 (37.9%) received antiplatelets and 236 (19.5%) had no antithrombotic medication. Compared to 2003-2004 and 2008-2010, there was a higher rate of pre-admission OAC in 2013-2015 (28.2% vs. 49.6%, p<0.001). After adjustment for possible confounders, factors associated with OAC pre-admission were young age (OR 0.74 per decade [95%CI 0.64-0.85]), previous stroke/TIA (OR 1.29 [95%CI 1.00-1.67]), absence of heart failure (OR 0.63 [95%CI 0.47-0.85]) and admission in 2013-2015 (OR 2.45 [95%CI 1.91-3.15]). Prescription of OAC at hospital discharge increased from 2003-2010 compared to 2013-2015 (45.2% vs. 69.5%, p < 0.001). CONCLUSIONS: Irrespective of temporal trends and despite given indication, more than half of all patients with known AF were not anticoagulated prior to the index stroke. In the NOAC era, there was an increase in OAC intake pre-stroke and a higher rate of OAC prescription at hospital discharge in stroke survivors with known AF.

Impact of pre-admission oral anticoagulation on ischaemic stroke volume, lesion pattern, and frequency of intracranial arterial occlusion in patients with atrial fibrillation.

Aims: Therapeutic oral anticoagulation on hospital admission reduces morbidity and mortality after acute ischaemic stroke in patients with atrial fibrillation (AF). The underlying mechanism is not fully understood. In order to assess the impact of INR-level on admission on stroke volume, lesion pattern and the frequency of intracranial arterial occlusion, we analysed serial MRI measurements in AF patients suffering acute ischaemic stroke. Methods and results: This subgroup analysis of the prospective '1000Plus' study included patients with acute ischaemic stroke and known AF or a first episode of AF in hospital. All patients underwent serial brain magnetic resonance imaging. Stroke patients were categorized as follows: Group1, phenprocoumon intake, international normalized ratio (INR) ≥1.7 on admission, no thrombolysis; Group2, INR < 1.7 on admission, thrombolysis; and Group3, INR < 1.7, no thrombolysis. In 98 AF patients {77 ± 9 years, 60% male; median National Institute of Health Stroke Scale [NIHSS] score on admission 5 (interquartile range [IQR] 2-8)} with known AF before admission, territorial infarction was less often found in Group 1 (n = 20) compared with Group 2 + 3 (20% vs. 47%, P = 0.022). Arterial occlusion rate on admission differed among groups (30%, 75%, and 35%, respectively, P = 0.004) but not between Group 1 vs. Group 2 + 3 (30% vs. 45%, P = 0.31). Median FLAIR volume on Days 5-7 was lower in Group1 compared with Group 2 (n = 20) [3.2 cm3 (IQR 1.1-11.3) vs. 18.6 cm3 (IQR 8.2-49.4); P = 0.009] but not compared with Group 2 + 3 [7.8 cm3 (IQR 1.6-25.9); P = 0.23]. An INR ≥ 1.7 on admission was not associated with smaller stroke volume in multivariable regression analysis. Adding 57 patients with a first AF episode during the in-hospital stay, similar results were observed in 155 AF patients. Conclusion: In this AF cohort, an INR ≥ 1.7 at stroke onset affects lesion pattern but does not affect significantly lower stroke volume and the frequency of arterial occlusion on admission.