Safety and efficacy of endovascular thrombectomy in patients with abnormal hemostasis: pooled analysis of the MERCI and multi MERCI trials

Stroke. 2009 Feb;40(2):516-22. doi: 10.1161/STROKEAHA.108.525089. Epub 2008 Dec 18.

Abstract

Background and purpose: Patients with abnormal hemostasis are not considered candidates for thrombolysis. We analyzed the MERCI/Multi MERCI cohort as an attempt to establish the risks and benefits of thrombectomy in this patient population.

Methods: Two patient groups were identified: Group 1 (n=35): patients with INR >1.7 or PTT >45 seconds or platelet count <100,000/microL; Group 2 (n=270): patients with INR <or=1.7, PTT <or=45 seconds, and platelet count >or=100,000/microL. Clinical, radiographic, and revascularization outcomes were subsequently compared.

Results: In Group 1, 20 patients had INR >1.7 (mean: 2.4; range: 1.8 to 4.9), 11 had PTT >45 seconds (mean: 95; range: 46 to 190), and 6 had platelets <100,000/microL (mean: 63 400; range: 16,000 to 94,000). Two patients had both INR >1.7 and PTT >45 seconds. The two groups did not significantly differ in terms of age, gender, baseline NIHSS scores, intraarterial thrombolytic use/dosage, or occlusion site. Time-to-treatment was slightly earlier in Group 1. There was no significant difference in the rates of revascularization (TIMI 2 to 3: 60% versus 65%), mortality (40% versus 38%), or major symptomatic intracranial hemorrhage (SICH; 8.6% versus 8.5%). Group 2 had higher rates of good clinical outcomes (9% versus 35%; P=0.002). This was likely related to a lower prestroke health status in Group 1 patients. In Group 1, successful revascularization was associated with improved outcomes (P=0.015) and lower mortality (24% versus 64%; P=0.033).

Conclusions: Patients with abnormal hemostasis who undergo thrombectomy do not appear to be at a higher risk for SICH but have lower rates of good outcomes. In this patient group, successful revascularization appears to be associated with improved clinical outcomes and lower mortality.

Publication types

  • Multicenter Study

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Brain / diagnostic imaging
  • Cerebral Angiography
  • Cerebral Hemorrhage / epidemiology
  • Cerebral Hemorrhage / surgery
  • Cohort Studies
  • Data Collection
  • Female
  • Hemostatic Disorders / physiopathology*
  • Humans
  • International Normalized Ratio
  • Male
  • Middle Aged
  • Neovascularization, Pathologic / pathology
  • Partial Thromboplastin Time
  • Platelet Count
  • Retrospective Studies
  • Risk Assessment
  • Thrombectomy* / adverse effects
  • Thrombosis / mortality
  • Thrombosis / physiopathology
  • Thrombosis / surgery*
  • Treatment Outcome