Delayed Cerebral Ischemia and Vasospasm After Aneurysmal Subarachnoid Hemorrhage: Impact of Stents and Dual Antiplatelet Therapy

BACKGROUND AND OBJECTIVES: As stent-assisted coiling and flow diversion permeate the treatment armamentarium for appropriately selected ruptured aneurysms, the effect of dual antiplatelet therapy (DAPT) on hemorrhagic complications is primarily scrutinized. However, the effect of DAPT and the presence of a stent on vasospasm and delayed cerebral ischemia (DCI) is less well studied. METHODS: Our prospectively maintained institutional database of intracranial aneurysms was queried for DCI and postaneurysmal subarachnoid hemorrhage (aSAH) vasospasm among patients undergoing stent coiling/flow diversion with subsequent usage of DAPT (S-DAPT). This group was compared with a matched control cohort of patients treated endovascularly not requiring antiplatelets (No S-DAPT). A propensity score was matched for age, sex, presenting clinical (Hunt-Hess), and radiographic (modified Fisher score) grade. Subgroup analyses were stratified by Hunt-Hess grade and DAPT regimen. Impact sizes were adjusted in multivariate analyses. RESULTS: Of 285 aSAH patients treated endovascularly over the evaluated period, 29% underwent S-DAPT. DCI occurred in 24.2% overall. The S-DAPT group showed a significant reduction in moderate or severe angiographic vasospasm (37% vs 55%, P = .02). The DCI risk was lower numerically (18% vs 27%), although this difference was not statistically significant ( P = .14). Subgroup analyses of angiographic vasospasm identified the benefit of S-DAPT in grade 1-3 aSAH (95% CI of absolute-risk-reduction [7.9%-35.8%], P = .003). The synergistic effect of S-DAPT was associated with a 2-fold lower risk of angiographic vasospasm in multivariate analyses (adjusted odds ratio 0.47, 95% CI [0.26-0.85], P = .01). CONCLUSION: S-DAPT was associated with a lower risk of post-aSAH cerebral vasospasm. Future studies with greater power to evaluate the effect on DCI as well are warranted.