Dual Antiplatelet Therapy Is Associated With Coagulopathy Detectable by Thrombelastography in Acute Stroke.

BACKGROUND: Thrombelastography (TEG) provides a global, dynamic measure of coagulation. We examined the effect of antiplatelet (AP) medications on coagulation in patients with acute stroke as measured by TEG. METHODS: We reviewed prospectively collected data on patients presenting with acute ischemic stroke (AIS) and spontaneous intracerebral hemorrhage (ICH) between 2009 and 2014. Patient demographics and baseline TEG values were compared among 4 different drug use groups: aspirin only, clopidogrel only, both aspirin and clopidogrel, and no AP. Multivariable regression models were conducted to compare the differences in TEG components. RESULTS: A total of 202 patients were included, 139 with AIS and 63 with ICH. Forty-eight (24%) patients were taking aspirin alone, 12 (6%) were taking clopidogrel, 16 (8%) dual AP, and 126 (62%) no AP. Dual AP use was associated with prolonged mean R (time to initiate clotting) of 5.5 minutes as compared to no AP use (4.6 minutes, P = .04). Additionally, mean maximal amplitude (MA; final clot strength) and angle (rate of clot formation) were decreased in the dual AP group (MA = 59.3 mm, angle = 57.8°) as compared to the no AP group (MA = 64.5 mm, angle = 64.5°; P = .04 and P = .01, respectively). Patients on single AP therapy (either aspirin or clopidogrel) did not differ from those on no AP therapy in any TEG parameters measured. CONCLUSION: Dual AP therapy is associated with a detectable coagulopathy which may have implications in the management of patients with AIS and hemorrhagic stroke. The effects of single AP therapy may not be demonstrated by TEG.

Association of Endovascular Thrombectomy vs Medical Management With Functional and Safety Outcomes in Patients Treated Beyond 24 Hours of Last Known Well: The SELECT Late Study.

Importance: The role of endovascular thrombectomy is uncertain for patients presenting beyond 24 hours of the time they were last known well. Objective: To evaluate functional and safety outcomes for endovascular thrombectomy (EVT) vs medical management in patients with large-vessel occlusion beyond 24 hours of last known well. Design, Setting, and Participants: This retrospective observational cohort study enrolled patients between July 2012 and December 2021 at 17 centers across the United States, Spain, Australia, and New Zealand. Eligible patients had occlusions in the internal carotid artery or middle cerebral artery (M1 or M2 segment) and were treated with EVT or medical management beyond 24 hours of last known well. Interventions: Endovascular thrombectomy or medical management (control). Main Outcomes and Measures: Primary outcome was functional independence (modified Rankin Scale score 0-2). Mortality and symptomatic intracranial hemorrhage (sICH) were safety outcomes. Propensity score (PS)-weighted multivariable logistic regression analyses were adjusted for prespecified clinical characteristics, perfusion parameters, and/or Alberta Stroke Program Early CT Score (ASPECTS) and were repeated in subsequent 1:1 PS-matched cohorts. Results: Of 301 patients (median [IQR] age, 69 years [59-81]; 149 female), 185 patients (61%) received EVT and 116 (39%) received medical management. In adjusted analyses, EVT was associated with better functional independence (38% vs control, 10%; inverse probability treatment weighting adjusted odds ratio [IPTW aOR], 4.56; 95% CI, 2.28-9.09; P < .001) despite increased odds of sICH (10.1% for EVT vs 1.7% for control; IPTW aOR, 10.65; 95% CI, 2.19-51.69; P = .003). This association persisted after PS-based matching on (1) clinical characteristics and ASPECTS (EVT, 35%, vs control, 19%; aOR, 3.14; 95% CI, 1.02-9.72; P = .047); (2) clinical characteristics and perfusion parameters (EVT, 35%, vs control, 17%; aOR, 4.17; 95% CI, 1.15-15.17; P = .03); and (3) clinical characteristics, ASPECTS, and perfusion parameters (EVT, 45%, vs control, 21%; aOR, 4.39; 95% CI, 1.04-18.53; P = .04). Patients receiving EVT had lower odds of mortality (26%) compared with those in the control group (41%; IPTW aOR, 0.49; 95% CI, 0.27-0.89; P = .02). Conclusions and Relevance: In this study of treatment beyond 24 hours of last known well, EVT was associated with higher odds of functional independence compared with medical management, with consistent results obtained in PS-matched subpopulations and patients with presence of mismatch, despite increased odds of sICH. Our findings support EVT feasibility in selected patients beyond 24 hours. Prospective studies are warranted for confirmation.

Cocaine Use is Associated with More Rapid Clot Formation and Weaker Clot Strength in Acute Stroke Patients.

INTRODUCTION: 1.1.Cocaine use is a known risk factor for stroke and has been associated with worse outcomes. Cocaine may cause an altered coagulable state by a number of different proposed mechanisms, including platelet activation, endothelial injury, and tissue factor expression. This study analyzes the effect of cocaine use on Thrombelastography (TEG) in acute stroke patients. PATIENT AND METHODS: 1.2.Patients presenting with Acute Ischemic Stroke (AIS) and spontaneous Intracerebral Hemorrhage (ICH) to a single academic center between 2009 and 2014 were prospectively enrolled. Blood was collected for TEG analysis at the time of presentation. Patient demographics and baseline TEG values were compared between two groups: cocaine and non-cocaine users. Multivariable Quantile regression models were used to compare the median TEG components between groups after controlling for the effect of confounders. RESULTS: 1.3.91 patients were included, 53 with AIS and 38 with ICH. 8 (8.8%) patients were positive for cocaine, 4 (50%) with AIS, and 4 (50%) with ICH. There were no significant differences in age, blood pressure, platelet count, or PT/PTT between the cocaine positive and cocaine negative group. Following multivariable analysis, and adjusting for factors known to influence TEG including stroke subtype, cocaine use was associated with shortened median R time (time to initiate clotting) of 3.8 minutes compared to 4.8 minutes in non-cocaine users (p=0.04). Delta (thrombin burst) was also earlier among cocaine users (0.4 minutes) compared with non-cocaine users (0.5 min, p=0.04). The median MA and G (measurements of final clot strength) were reduced in cocaine users (MA=62.5 mm, G=7.8 dynes/cm2) compared to non-cocaine users (MA=66.5 mm, G=10.1 dynes/cm2; p=0.047, p=0.04, respectively). CONCLUSION: 1.4.Cocaine users demonstrate more rapid clot formation but reduced overall clot strength based on admission TEG values.