Stent-retriever thrombectomy after intravenous t-PA vs. t-PA alone in stroke.

BACKGROUND: Among patients with acute ischemic stroke due to occlusions in the proximal anterior intracranial circulation, less than 40% regain functional independence when treated with intravenous tissue plasminogen activator (t-PA) alone. Thrombectomy with the use of a stent retriever, in addition to intravenous t-PA, increases reperfusion rates and may improve long-term functional outcome. METHODS: We randomly assigned eligible patients with stroke who were receiving or had received intravenous t-PA to continue with t-PA alone (control group) or to undergo endovascular thrombectomy with the use of a stent retriever within 6 hours after symptom onset (intervention group). Patients had confirmed occlusions in the proximal anterior intracranial circulation and an absence of large ischemic-core lesions. The primary outcome was the severity of global disability at 90 days, as assessed by means of the modified Rankin scale (with scores ranging from 0 [no symptoms] to 6 [death]). RESULTS: The study was stopped early because of efficacy. At 39 centers, 196 patients underwent randomization (98 patients in each group). In the intervention group, the median time from qualifying imaging to groin puncture was 57 minutes, and the rate of substantial reperfusion at the end of the procedure was 88%. Thrombectomy with the stent retriever plus intravenous t-PA reduced disability at 90 days over the entire range of scores on the modified Rankin scale (P<0.001). The rate of functional independence (modified Rankin scale score, 0 to 2) was higher in the intervention group than in the control group (60% vs. 35%, P<0.001). There were no significant between-group differences in 90-day mortality (9% vs. 12%, P=0.50) or symptomatic intracranial hemorrhage (0% vs. 3%, P=0.12). CONCLUSIONS: In patients receiving intravenous t-PA for acute ischemic stroke due to occlusions in the proximal anterior intracranial circulation, thrombectomy with a stent retriever within 6 hours after onset improved functional outcomes at 90 days. (Funded by Covidien; SWIFT PRIME ClinicalTrials.gov number, NCT01657461.).

Age dependency of successful recanalization in anterior circulation stroke: the ENDOSTROKE study.

BACKGROUND: Clinical outcome after endovascular stroke therapy (EVT) for proximal anterior circulation stroke is often disappointing despite high recanalization rates. The ENDOSTROKE study aims to determine predictors of clinical outcome in patients undergoing EVT. Here we focus on the impact of age and recanalization on proximal middle cerebral artery (M1-MCA) or carotid T occlusion. METHODS: ENDOSTROKE is an investigator-initiated, industrially independent multicenter registry launched in January, 2011, for consecutive patients undergoing EVT for large-vessel stroke. This analysis focuses on patients treated in 11 academic and nonacademic stroke centers with angiographically proven M1-MCA (n = 259) or carotid T occlusion (n = 103). Recanalization was defined as Thrombolysis in Myocardial Infarction (TIMI) score 2 or 3, and in patients with available Thrombolysis in Cerebral Ischemia (TICI) data (n = 309) as TICI scores 2b-3. Good outcome was defined as modified Rankin Scale (mRS) score of 0-2 assessed after 3 months or later. RESULTS: The median age was 68 years (25th and 75th percentiles: 56, 76 years), and the median National Institutes of Health Stroke Scale (NIHSS) score at admission was 16 (13, 19); 41% of the patients had a favorable (mRS scores 0-2), and 59% had an unfavorable (mRS scores 3-6) outcome; 83% reached TIMI 2-3 flow. Independent predictors of good outcome were younger age, lower initial NIHSS scores, TIMI 2/3 recanalization and lower serum glucose levels. Outcome was highly dependent on patients' age: 60% of the patients within the lowest age quartile (range: 18-56 years) experienced good clinical outcome, decreasing stepwise over 47% (57-68 years) and 37% (69-76 years) to 17% in the highest age quartile (77-94 years). The proportion of patients with poor clinical outcome despite TIMI 2/3 recanalization ('futile recanalization') increased dramatically from only 29% in the lowest age quartile over 34% and 40% (2nd and 3rd age quartiles) up to 53% in the highest age quartile. Results were similar in patients with available TICI scores, with 'futile recanalization' rates increasing from 24% to 46% (lowest to highest age quartile). CONCLUSIONS: This study emphasizes the dramatic impact of patients' age on outcome in EVT for M1-MCA or carotid T occlusion, even in the presence of recanalization. Reasons for this age-related decrease in clinically successful recanalization rates urgently need clarification and may comprise patient-related factors (age-related increase in cardioembolic strokes, collateral status, comorbidities) as well as periprocedural issues (tortuous vessel anatomy in the elderly, age-dependent negative impact of general anesthesia in EVT).