Prior Anticoagulation in Patients with Ischemic Stroke and Atrial Fibrillation

Abstract

Objective The aim was to evaluate, in patients with atrial fibrillation (AF) and acute ischemic stroke, the association of prior anticoagulation with vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs) with stroke severity, utilization of intravenous thrombolysis (IVT), safety of IVT, and 3‐month outcomes. Methods This was a cohort study of consecutive patients (2014–2019) on anticoagulation versus those without (controls) with regard to stroke severity, rates of IVT/mechanical thrombectomy, symptomatic intracranial hemorrhage (sICH), and favorable outcome (modified Rankin Scale score 0–2) at 3 months. Results Of 8,179 patients (mean [SD] age, 79.8 [9.6] years; 49% women), 1,486 (18%) were on VKA treatment, 1,634 (20%) on DOAC treatment at stroke onset, and 5,059 controls. Stroke severity was lower in patients on DOACs (median National Institutes of Health Stroke Scale 4, [interquartile range 2–11]) compared with VKA (6, [2–14]) and controls (7, [3–15], p < 0.001; quantile regression: β −2.1, 95% confidence interval [CI] −2.6 to −1.7). The IVT rate in potentially eligible patients was significantly lower in patients on VKA (156 of 247 [63%]; adjusted odds ratio [aOR] 0.67; 95% CI 0.50–0.90) and particularly in patients on DOACs (69 of 464 [15%]; aOR 0.06; 95% CI 0.05–0.08) compared with controls (1,544 of 2,504 [74%]). sICH after IVT occurred in 3.6% (2.6–4.7%) of controls, 9 of 195 (4.6%; 1.9–9.2%; aOR 0.93; 95% CI 0.46–1.90) patients on VKA and 2 of 65 (3.1%; 0.4–10.8%, aOR 0.56; 95% CI 0.28–1.12) of those on DOACs. After adjustments for prognostic confounders, DOAC pretreatment was associated with a favorable 3‐month outcome (aOR 1.24; 1.01–1.51). Interpretation Prior DOAC therapy in patients with AF was associated with decreased admission stroke severity at onset and a remarkably low rate of IVT. Overall, patients on DOAC might have better functional outcome at 3 months. Further research is needed to overcome potential restrictions for IVT in patients taking DOACs. ANN NEUROL 2021;89:42–53

Challenges of Acute Ischemic Stroke Treatment in Orally Anticoagulated Patients via Telemedicine

“…Indeed, prior NOAC intake represented a major obstacle in administering IVT. These findings are in line with data from conventional in-person settings [ 3 , 5 ].…”

“…Nevertheless, while the relative risk of hemorrhagic strokes has been halved by using NOACs as compared to warfarin, a vitamin K antagonist (VKA), the rate of ischemic stroke has remained largely unchanged [ 1 ]. Consequently, acute ischemic stroke (AIS) develops frequently despite oral anticoagulation [ 2 , 3 ]. Current evidence about the optimal treatment strategies in patients with AIS under therapy with NOACs is still limited [ 4 ].…”

Recanalisation therapies for acute ischaemic stroke in patients on direct oral anticoagulants

“… 31 32 However, 18 of the 20 certified stroke units in Switzerland have access to specific tests for patients who had a stroke with comparable safety results and treatment metrics. 33 …”

“…The overall reported rate of sICH in this study was 2% (2 patients) and none of the patients selected using DOAC plasma levels had sICH. Data from the Swiss Stroke Registry of 69 patients on DOACs receiving IVT found no increased risk of sICH compared with patients without anticoagulation and those on VKAs with INR ≤1.7 33 (18 of 23 centres used DOAC plasma levels for patient selection).…”

Coagulation Assay and Stroke Severity upon Admission of Patients with Cardioembolic Cerebral Infarction during Direct Oral Anticoagulant Use

“…[3][4][5] Furthermore, it has been reported that the proportion of patients with large vessel occlusion (LVO) at the onset of cerebral infarction is lower in patients receiving DOACs. 6 Moreover, low DOAC plasma levels are reportedly associated with LVO and higher stroke severity on admission to hospital. 7 However, the measurement of plasma DOAC levels is difficult by routine testing in clinical practice.…”