Elena Zapata-Arriaza, MD

Meinel TR, Kniepert JU, Seiffge DJ, Gralla J, Jung S, Auer E, et al. Endovascular Stroke Treatment and Risk of Intracranial Hemorrhage in Anticoagulated Patients. Stroke. 2020;51:892–898.

Symptomatic intracranial hemorrhage (sICH) involves a potential complication in patients treated with rtpa or mechanical thrombectomy (MT), which influences functional and vital prognosis of ischemic stroke patients. Patients under oral anticoagulation (OAC) suffer higher risk of sICH per se; however, the association of mentioned oral treatment with recanalization therapies (IV fibrinolysis or MT) may increase cerebral bleeding. This is the aim of Dr. Meinel and colleagues, among others, like mortality and sICH risk in MT patients under OAC, sensitivity analysis with patients with confirmed therapeutic anticoagulation activity, and finally the presentation of a meta-analysis about the topic.

The authors performed a retrospective, multicenter non-randomized observational study to investigate safety and efficacy of a market-release neurothrombectomy device, including their data in the BEYOND-SWIFT registry. Patients were grouped according to their OAC intake prior to admission: Group 1: VKA (vitamin K antagonist); Group 2: DOACs (Direct oral anticoagulants); Group 3: No OAC. The primary endpoint was sICH rate (according to ECASS II (European Co-Operative Acute Stroke Study-II) criteria). The secondary endpoints were technical efficacy and all-cause mortality at 3 months.

Among 1932 included patients, the main finding of the study is that VKA prescription was associated with increased odds for sICH and mortality (adjusted odds ratio [aOR], 2.55) as compared with the control group, whereas no association with DOAC intake was observed. Sensitivity analyses considering only patients within the confirmed therapeutic anticoagulation range did not alter the findings. The meta-analysis corroborated prior observations, yielding an increased rate of sICH and mortality in VKA patients after endovascular procedure but not in DOAC patients. Regarding technical efficacy, rate of successful reperfusion was higher in DOACs patients, which needed shorter procedural times.

These findings show results in line with randomized clinical trials carried out to compare the efficacy and safety of direct anticoagulants versus VKA. The latter show irregular efficacy and are affected by their variability throughout the day, alternating periods of poor efficacy (infratherapeutic INR) with overdose stages that increase the risk of bleeding per se. In the case of patients undergoing mechanical thrombectomy and/or rtPa, we treated patients with a possible residual ischemic lesion that could present a hemorrhagic transformation on its own. Although the therapeutic ranges have not been shown to affect the risk of sICH, it is true that VKAs increase the risk of such complication and could be related to the daily individual variability of the dosage ranges. In any case, these patients should not be excluded from the indication for MT; however, after performing this, we should further explore risk predictors in this subgroup of patients in order to establish action protocols that minimize the risk of sICH and mortality in patients who are under VKA treatment.