Introduction: The purpose of this study was to identify the outcomes of surgical management in patients with unruptured low-grade bAVMs non-neurologically impaired patients and compare them with the natural history of bAVMs.
Methods: A retrospective review of all patients who underwent surgical resection, with or without preoperative embolization, for unruptured Spetzler-Martin grade I or II bAVMs 2004 through 2014 was performed. Patients with minimal symptoms (headaches and seizures only) and intact neurological presentation were included. Patients with any focalized neurological deficit, hemorrhage, and/or clinical impairment were excluded from analysis. The primary endpoint, identical to the one used in the ARUBA trial, was a composite of stroke or death from any cause. Clinical outcome was evaluated using the modified Rankin Scale (mRS).
Results: Of the 61 patients (17 grade I, 44 grade II bAVM) meeting inclusion criteria, 28 (45.9%) were male, mean age was 38.2±17.2 years old. No patients experienced a major stroke (primary outcome), death, or severe neurological impairment associated with management. Cure was achieved in all patients regardless of grade, and no recurrences were observed at last follow-up (mean 39.8±32.1 months). Immediately after surgery and at last follow-up, all grade I bAVM patients were non-clinically impaired and 94.1% had a good outcome. At last follow-up, 97.7% of grade II bAVM patients were neurologically intact and 97.7% had a good outcome. Seizures completely resolved without further medication in 60.7% of patients. Postoperative and post-embolization complication rate was 6.3% and 4.7%, respectively. At last follow-up, an impaired clinical status (mRS =2) was present in only 1.6% of patients.
Conclusions: Surgical resection of unruptured low-grade bAVMS in non-impaired patients is safe and results in a low rate of clinical deterioration in experienced hands. Patients present improvement from transient deficits following surgery, which could be considered superior than the natural history.
Patient Care: Surgical management of unruptured low-grade bAVM in neurologically intact patients provides better outcomes than the natural history of the disease.
Learning Objectives: Surgical management of unruptured low-grade bAVMs in non-neurologically impaired patients is a safe procedure in experienced hands, with good clinical outcomes and less risk of reaching primary outcome than natural history.