Influence of Platelet Count on Procedure-Related Outcomes After Mechanical Thrombectomy for Large Vessel Occlusion: A Systematic Review and Meta-Analysis.

OBJECTIVE:To compare outcomes between patients who underwent mechanical thrombectomy for large vessel occlusion based on platelet count: low versus normal. METHODS:Three studies were included with a pooled cohort of 1125 patients. Data points were collected and pooled by meta-analysis of proportions via a logit transformation to provide a summary statistic. Both fixed-effect and random-effects models were recruited for the analysis. In this meta-analysis, risk of developing symptomatic intracranial hemorrhage, unfavorable clinical outcomes (modified Rankin Scale score >3), and mortality of patients with low platelet counts were compared with patients with normal platelet counts according to the criteria for inclusion used by each study. RESULTS:Of patients, 50 (4.7%) had low platelet count, and 1075 (95.3%) had normal platelet count. Patients in the low platelet count group had a substantially higher risk of mortality (risk ratio 1.93, 95% confidence interval 1.43-2.60, P < 0.0001, I2 = 0%), but no differences in clinical outcomes (risk ratio 0.66, 95% confidence interval 0.40-1.11, P = 0.12, I2 = 0%) or symptomatic intracranial hemorrhage (risk ratio 2.03, 95% confidence interval 0.87-4.70, P = 0.10, I2 = 15%) were noted. CONCLUSIONS:Patients with low platelet counts had increased mortality compared with patients with normal platelet counts following mechanical thrombectomy for large vessel occlusion.