The role of nimodipine in preventing cerebral ischaemia and neurological deterioration in cerebral arteriovenous malformations: a systematic review

INTRODUCTION: Cerebral arteriovenous malformations (cAVMs) are congenital cerebrovascular anomalies that are associated with a high risk of intracerebral bleeding, which may be exacerbated by cerebral vasospasm (CVS). Despite advances in treatment modalities such as microsurgical resection, stereotactic radiosurgery, and endovascular embolization, CVS remains a significant concern, often precipitating significant neurological morbidity and mortality. Nimodipine, a calcium channel blocker, is widely used in aneurysmal subarachnoid haemorrhage (aSAH) to reduce neurological deficits. However, its role in cAVM-related CVS remains unclear. MATERIALS AND METHODS: We performed a comprehensive review, collecting all cases reporting nimodipine use in adult cAVM patients in the literature. We aimed to identify the role of nimodipine in preventing cerebral ischaemia and deterioration in these patients. We executed a qualitative synthesis and calculated risk ratios for aneurysmal presence and odds ratios between the use and absence of nimodipine. Fisher's exact test was also used to calculate p-values when n < 5. RESULTS: A total of 12 articles were included, reporting 27 patients with a mean age of 41.3 years and equal gender distribution. Postoperative neurological deficits were reported in 40.7% of patients receiving nimodipine. Patients who received nimodipine had lower mortality (10.7%) compared with those who did not (33.3%). CONCLUSION: Current evidence is confined to small, heterogeneous case series; prospective, controlled studies with standardised nimodipine regimens are required to define its role in cAVM-related vasospasm and neurological outcome.