International Stroke Conference
Pouya Tahsili-Fahadan, MD
Vasospasm and delayed cerebral ischemia (DCI) following subarachnoid hemorrhage (SAH) are a major cause of morbidity and mortality. The only proven medication to improve outcomes after SAH is nimodipine.
Cilostazol is a phosphodiesterase III inhibitor that has been shown to decrease vasospasm and DCI in animal studies, as well as in small clinical series. The proposed mechanisms include increase in endothelial release of nitric oxide (NO) and inhibition of platelet derived growth factor (PDGF), vascular smooth muscle proliferation, and expression of adhesion molecules on endothelium.
Dr. Muhammad F. Ishfaq presented the results of a meta-analysis of previous studies on the effects of cilostazol on vasospasm and DCI. A total of 6 studies were included in the meta-analysis after reviewing 33 studies (three studies were randomized clinical trials). The primary end-point was incidence of DCI secondary to vasospasm. Secondary end-points included: angiographic vasospasm, new stroke, mortality, and major disability (defined as modified Rankin scale 4-6 at discharge and follow-up exams).
The vast majority of the cases underwent microsurgical clipping. A total daily dose of 200 mg of cilostazol (divided in 1 or 2 doses) was administered for 14 days after surgery. Cilostazol administration was associated with a significant decrease in angiographic vasospasm (RR 0.67, 95% CI 0.51-0.84) and major disability (RR 0.59, 95% CI 0.44-0.89), but no significant mortality advantage (RR 0.64, 95% CI 0.15-2.76).
A notable limitation of this study was application of various clinical and/or neuroimaging definitions for vasospasm and DCI. New infarcts were mostly detected based on CT scan that can miss small or posterior strokes. Also high-grade SAH cases that carry the highest risk for DCI were excluded in some studies. In addition, a high rate of clipping in the studied population does not reflect the common practice of endovascular coiling in the United States. Despite all these limitations, looking for new and more effective preventive treatments for vasospasm and DCI is a step forward.
Dr. Adnan Qureshi, the senior author of the study, was agreeable to representation of the meta-analysis results on Blogging Stroke.