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

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.

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.

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.

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.