Introduction: The use of an intracranial stent requires dual antiplatelet therapy to avoid in-stent thrombosis. We investigated whether use of dual antiplatelet therapy is a risk factor for hemorrhagic complications in patients undergoing ventriculoperitoneal shunt for hydrocephalus following aneurysmal subarachnoid hemorrhage (aSAH).

Methods: Patients were given 325mg acetylsalicylic acid and 600mg clopidogrel during coil/stent procedure and maintained on dual antiplatelet therapy with acetylsalicylic acid 325mg and clopidogrel 75mg daily for 6 weeks post-treatment. Placement of ventriculoperitoneal shunt occurred at a delayed time during initial hospitalization, usually between 7 and 21 days following aSAH. Post-operative computed tomography scans were reviewed for hemorrhages.

Results: 206 patients were admitted to the University of Iowa Hospitals and Clinics with aSAH between July 2009 and October 2010. Thirty-seven patients were treated with ventriculoperitoneal shunt for persistent hydrocephalus. Twelve patients(32%) had previously undergone stent-assisted coiling and were on dual anti-platelet therapy. The remaining 25(68%) patients had undergone surgical clipping or aneurysm coiling and were not on antiplatelet therapy. Four(10.8%) new intracranial hemorrhages associated with ventriculoperitoneal shunt placement were observed. All four hemorrhages (33%) occurred in patients on dual antiplatelet therapy for stent-assisted coiling, compared to no new intracranial hemorrhages in patients not on dual antiplatelet therapy [4/12(33%) vs. 0/25(0%), p=0.0075]. All four hemorrhages occurred along the ventricular catheter tract. Only one hemorrhage (1/12, 8.3%) was clinically significant, resulting in proximal shunt occlusion requiring revision. The patient did not incur any permanent morbidity related to the hemorrhage.

Conclusions: This small series suggests placement of ventriculoperitoneal shunt in patients on dual anti-platelet therapy to be associated with an increased, but low rate of symptomatic intracranial hemorrhage. In patients who are poor candidates for open surgical clipping and with 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.

Patient Care: This study will alert Neurosurgeons to the potential hazards of dual antiplatelet therapy in aneurysmal subarachnoid hemorrhage patients requiring treatment of hydrocephalus. The highlighted example of clinically significant hemorrhage should also serve to alert clinicians of small hemorrhage as a potential cause of shunt malfunction. Awareness of such risks can better inform treatment strategies in complex aneurysmal subarachnoid hemorrhage patients, and hopefully result in better patient outcomes.

Learning Objectives: At the completion of this session, participants should be able to 1) Appreciate the complexity of clinical decision-making in hydrocephalic aneurysmal SAH patients who are treated with stent-assisted coil embolization, 2) Recognize hemorrhage risk during ventriculoperitoneal shunt procedures in patients on dual antiplatelet therapy and incorporate this knowledge into treatment strategies for these complex patients.

References: 1. Amenta PS, Dalyai RT, Kung D, Toporowski A, Chandela S, Hasan D, et al: Stent-assisted coiling of wide-necked aneurysms in the setting of acute subarachnoid hemorrhage: experience in 65 patients. Neurosurgery 70:1415-1429; discussion 1429, 2012 2. Benitez RP, Silva MT, Klem J, Veznedaroglu E, Rosenwasser RH: Endovascular occlusion of wide-necked aneurysms with a new intracranial microstent (Neuroform) and detachable coils. Neurosurgery 54:1359-1367; discussion 1368, 2004 3. Bodily KD, Cloft HJ, Lanzino G, Fiorella DJ, White PM, Kallmes DF: Stent-assisted coiling in acutely ruptured intracranial aneurysms: a qualitative, systematic review of the literature. AJNR Am J Neuroradiol 32:1232-1236, 2011 4. Chalouhi N, Dumont AS, Hasan D, Tjoumakaris S, Gonzalez LF, Starke RM, et al: Is packing density important in stent-assisted coiling? Neurosurgery 71:381-386; discussion 386-387, 2012 5. Chalouhi N, Jabbour P, Gonzalez LF, Dumont AS, Rosenwasser R, Starke RM, et al: Safety and efficacy of endovascular treatment of basilar tip aneurysms by coiling with and without stent assistance: a review of 235 cases. Neurosurgery 71:785-794, 2012 6. Fiorella D, Albuquerque FC, Han P, McDougall CG: Preliminary experience using the Neuroform stent for the treatment of cerebral aneurysms. Neurosurgery 54:6-16; discussion 16-17, 2004 7. Gao X, Liang G, Li Z, Wei X, Hong Q: Complications and adverse events associated with Neuroform stent-assisted coiling of wide-neck intracranial aneurysms. Neurol Res 33:841-852, 2011 8. Garell PC, Mirsky R, Noh MD, Loftus CM, Hitchon PW, Grady MS, et al: Posterior ventricular catheter burr-hole localizer. Technical note. J Neurosurg 89:157-160, 1998 9. Hoh BL, Kleinhenz DT, Chi YY, Mocco J, Barker FG, 2nd: Incidence of ventricular shunt placement for hydrocephalus with clipping versus coiling for ruptured and unruptured cerebral aneurysms in the Nationwide Inpatient Sample database: 2002 to 2007. World Neurosurg 76:548-554, 2011 10. Howard MA, 3rd, Srinivasan J, Bevering CG, Winn HR, Grady MS: A guide to placement of parietooccipital ventricular catheters. Technical note. J Neurosurg 82:300-304, 1995 11. Ingall TJ, Whisnant JP, Wiebers DO, O'Fallon WM: Has there been a decline in subarachnoid hemorrhage mortality? Stroke 20:718-724, 1989 12. Kaluza GL, Joseph J, Lee JR, Raizner ME, Raizner AE: Catastrophic outcomes of noncardiac surgery soon after coronary stenting. J Am Coll Cardiol 35:1288-1294, 2000 13. Kung DK, Policeni BA, Capuano AW, Rossen JD, Jabbour PM, Torner JC, et al: Risk of ventriculostomy-related hemorrhage in patients with acutely ruptured aneurysms treated using stent-assisted coiling. J Neurosurg 114:1021-1027, 2011 14. Little AS, Zabramski JM, Peterson M, Goslar PW, Wait SD, Albuquerque FC, et al: Ventriculoperitoneal shunting after aneurysmal subarachnoid hemorrhage: analysis of the indications, complications, and outcome with a focus on patients with borderline ventriculomegaly. Neurosurgery 62:618-627; discussion 618-627, 2008 15. Lodi YM, Latorre JG, El-Zammar Z, Swarnkar A, Deshaies E, Fessler RD: Stent assisted coiling of the ruptured wide necked intracranial aneurysm. J Neurointerv Surg 4:281-286, 2012 16. Martin AR, Cruz JP, Matouk CC, Spears J, Marotta TR: The pipeline flow-diverting stent for exclusion of ruptured intracranial aneurysms with difficult morphologies. Neurosurgery 70:21-28; discussion 28, 2012 17. McAuliffe W, Wenderoth JD: Immediate and midterm results following treatment of recently ruptured intracranial aneurysms with the Pipeline embolization device. AJNR Am J Neuroradiol 33:487-493, 2012 18. O'Kelly CJ, Kulkarni AV, Austin PC, Urbach D, Wallace MC: Shunt-dependent hydrocephalus after aneurysmal subarachnoid hemorrhage: incidence, predictors, and revision rates. Clinical article. J Neurosurg 111:1029-1035, 2009 19. Piotin M, Blanc R, Spelle L, Mounayer C, Piantino R, Schmidt PJ, et al: Stent-assisted coiling of intracranial aneurysms: clinical and angiographic results in 216 consecutive aneurysms. Stroke 41:110-115, 2010 20. Sharma AK, Ajani AE, Hamwi SM, Maniar P, Lakhani SV, Waksman R, et al: Major noncardiac surgery following coronary stenting: when is it safe to operate? Catheter Cardiovasc Interv 63:141-145, 2004 21. Than KD, Rohatgi P, Wilson TJ, Gregory Thompson B: Perioperative management of a neurosurgical patient requiring antiplatelet therapy. J Clin Neurosci 19:1316-1320, 2012