Effects of sex on mechanical embolectomy outcome

Given that women have demonstrated a greater margin of benefit than men from treatment with thrombolytics in certain acute stroke trials, the current study explored whether this sex effect extends to mechanical embolectomy and can be explained by revascularization rate. The study included the 305 patients enrolled in the Mechanical Embolus Removal in Cerebral Ischemia (MERCI) and Multi MERCI trials. Demographic, risk factor, and procedural characteristics were evaluated in women and men. Odds ratios for outcomes by sex were compared in patients with revascularization and those without revascularization, defined as a Thrombolysis in Myocardial Infarction score of 2-3 at the end of the procedure. Outcomes included a modified Rankin Scale (mRS) score of 0-2 and mortality at 90 days, as well as the presence of symptomatic intracranial hemorrhage (sICH). Patient and procedural characteristics did not differ between women and men except for mean age (women, 70.1 years; men, 64.8 years; P = .003), hypertension (women, 78.0%; men, 65.5%; P = .021), and number of vertebrobasilar occlusions (women, 8/159 [5.0%]; men, 20/146 [13.7%]; P = .01). Revascularization was significantly associated with favorable outcomes in both women and men (P < .0001), and rates of favorable outcome, mortality, and sICH did not differ between women and men when the vessel was revascularized. Likewise, mechanical embolectomy with the Merci Retriever was not associated with different outcomes in women and men when the vessel was revascularized. Our data suggest that the sex differences seen in thrombolytic trials might be due to factors other than immediate postprocedural large vessel opening.