OBJECT: The use of an intracranial stent requires dual antiplatelet therapy to avoid in-stent thrombosis. In this study, the authors sought to investigate whether the use of dual antiplatelet therapy is a risk factor for hemorrhagic complications in patients undergoing permanent ventriculoperitoneal (VP) shunt for hydrocephalus following aneurysmal subarachnoid hemorrhage (aSAH). METHODS: Patients were given 325 mg acetylsalicylic acid and 600 mg clopidogrel during the coil/stent procedure, and they were maintained on dual antiplatelet therapy with acetylsalicylic acid 325 mg daily and clopidogrel 75 mg daily during hospitalization and for 6 weeks posttreatment. Patients underwent placement of VP shunt at a later time during initial hospitalization, usually between 7 and 21 days following aSAH. Postoperative CT scans obtained in each study patient were reviewed for hemorrhages related to placement of the VP shunt. RESULTS: A total of 206 patients were admitted to the University of Iowa Hospitals and Clinics with aSAH between July 2009 and October 2010. Thirty-seven of these patients were treated with a VP shunt for persistent hydrocephalus. Twelve patients (32%) had previously undergone stent-assisted coiling and were on dual antiplatelet therapy with acetylsalicylic acid and clopidogrel. The remaining 25 patients (68%) had undergone surgical clipping or aneurysm coiling and were not receiving antiplatelet therapy at the time of surgery. Four cases (10.8%) of new intracranial hemorrhages associated with VP shunt placement were observed. All 4 hemorrhages (33%) occurred in patients on dual antiplatelet therapy for stent-assisted coiling. No new intracranial hemorrhages were observed in patients not receiving dual antiplatelet therapy. The difference in hemorrhagic complications between the 2 groups was statistically significant (4 [33%] of 12 vs 0 of 25, p = 0.0075]). All 4 hemorrhages occurred along the tract of the ventricular catheter. Only 1 hemorrhage (1 [8.3%] of 12) was clinically significant as it resulted in occlusion of the proximal shunt catheter and required revision of the VP shunt. The patient did not suffer any permanent morbidity related to the hemorrhage. The remaining 3 hemorrhages were not clinically significant. CONCLUSIONS: This small clinical series suggests that placement of a VP shunt in patients on dual antiplatelet therapy may be associated with an increased, but low, rate of symptomatic intracranial hemorrhage. It appears that in patients who are poor candidates for open surgical clipping and have aneurysms amenable to stent-assisted coiling, the risk of symptomatic hemorrhage may be an acceptable trade-off for avoiding risks associated with discontinuation of antiplatelet therapy. The authors' results are preliminary, however, and require confirmation in larger studies.