Predictors of Outcome after Mechanical Thrombectomy for Anterior Circulation Large Vessel Occlusion in Patients Aged ≥80 Years

Abstract

Background: There is uncertainty about the role of endovascular recanalization procedures for the treatment of acute ischemic stroke in patients aged ≥80 years. Therefore, careful patient selection is mandatory. Our aim was to find valid predictors of clinical outcome after mechanical thrombectomy (mTE) based on the sparse information available in the emergency setting. Methods: We included consecutive patients aged ≥80 years treated by mTE for anterior circulation thromboembolic vessel occlusion in our department between January 2008 and January 2013. Successful recanalization was defined as a thrombolysis in cerebral infarction (TICI) score of 2b or 3. The rates of parenchymal hemorrhage types I (PHI) and II (PHII) according to the ECASS definition and the rate of focal and diffuse subarachnoid hemorrhage (SAH) were reported. A modified Ranking scale (mRS) score of 0-2 at 90 days was defined as a favorable outcome. We evaluated the influence of gender, smoking habits, atrial fibrillation, diabetes, hypertension, hyperlipidemia, coronary artery and peripheral artery disease, National Institutes of Health Stroke Scale (NIHSS) score, Totaled Health Risks in Vascular Events (THRIVE) score, Alberta Stroke Program Early CT Score (ASPECTS), and duration of symptoms on favorable outcome. Significant predictors were then included in a stepwise logistic regression analysis. Odds ratios (OR), 95% confidence intervals (CI), and receiver operating characteristics (ROC) curves were calculated. p < 0.05 was considered statistically significant. Results: In the defined period, we treated 109 patients aged ≥80 years with 116 occluded anterior circulation target vessels. Successful recanalization was achieved in 87.9% of the targets. The rates of PHI, PHII, and focal and diffuse SAH were 6.4, 5.5, 12.8, and 7.3%, with an overlap between PH and SAH. The combined rate of PHII and/or diffuse SAH was 9.2%. Despite good recanalization rates and reasonable rates of hemorrhage, only 19 patients (17.4%) were functionally independent at 90 days. An additional 12 patients (11.0%) suffered from moderate disability (mRS score 3), 26 (23.9%) were severely disabled (mRS score 4-5) and 52 (47.7%) were deceased. NIHSS, ASPECTS, and THRIVE scores significantly predicted a favorable outcome. Stepwise logistic regression identified NIHSS (OR 0.89; 95% CI 0.82-0.96; p = 0.009) and ASPECTS (OR 2.27; 95% CI 1.28-4.02; p = 0.005) as independent predictors. The ROC area was 0.81. Conclusion: ASPECTS and NIHSS were independent predictors of a favorable outcome in patients aged ≥80 years after mTE for anterior circulation large vessel occlusion and may support decision making with regard to the treatment modality. Since the chances of gaining functional independence are limited, careful consideration of each individual case is mandatory. Further studies comparing endovascular and standard treatment in octogenarians are warranted.