Descriptive Study of Aneurysmal and Nonaneurysmal Subarachnoid Hemorrhage and the Role of Confirmative Digital Subtraction Angiography in Patients with Nonaneurysmal Subarachnoid in Puerto Rico

Cerebrovascular disease is the fifth cause of mortality in Puerto Rico. There is no descriptive study for the presentation of spontaneous subarachnoid hemorrhage (SAH) in our institution. Therefore, our primary aim was to perform a retrospective analysis of adult patients with spontaneous SAH and assess the need for digital subtraction angiography (DSA) after initially aneurysm-negative computed tomography angiography (CTA) in nonaneurysmal SAH, specifically perimesencephalic SAH (PM-SAH). Medical records of 324 adult patients with aneurysmal and nonaneurysmal SAH treated at the Puerto Rico Medical Center from 2015 to 2018 were retrospectively analyzed. Demographics, past medical history, clinical characteristics, and imaging information were extracted. Acute hydrocephalus, mortality at 30 days, prevalence of diffuse SAH pattern, and Fisher and World Federation of Neurosurgical Societies grades >2 on initial examination were higher in the aneurysmal SAH subgroup. Patients with nonaneurysmal SAH had a significantly higher prevalence of chronic kidney disease and diabetes mellitus. Of the patients with nonaneurysmal PM-SAH with initial aneurysm-negative CTA, 100% were subsequently confirmed by DSA. Patients in the aneurysmal SAH subgroup correlated with an increased disease burden. Furthermore, this study shows that in our population, patients with nonaneurysmal PM-SAH with a low Fisher and World Federation of Neurosurgical Societies grade and with comorbid diabetes mellitus and chronic kidney disease may not need DSA after a negative initial CTA result.