Grades of brain arteriovenous malformations and risk of hemorrhage and death

Abstract

Objective To assess the relationship of the grade of unruptured and untreated Brain Arteriovenous Malformations (AVMs), with the risk of subsequent stroke and death during follow‐up. Methods This prospective study was drawn from a cohort of adult patients with unruptured AVMs, who participated in the conservative treatment arm (medical management only for headache or seizures) of the randomized clinical trial of unruptured brain AVMs (ARUBA study). The grade of AVMs (Spetzler–Martin scale) was dichotomized into categories: AVMs of grades I and II were considered low grade; AVMs of grades III and IV were considered high grade. There were no grade V AVM patients in ARUBA. The primary outcome was symptomatic stroke (hemorrhagic or ischemic – documented by imaging) or death. Results The conservative treatment group had 123 patients (“as treated” analysis). 71 (57.7%) had lesions characterized for this analysis as low‐grade lesions and 52 (42.2%) as high grade. From the total of 10 (8.13%) primary outcomes, three occurred (4.22%) in low‐grade AVMs and seven (13.46%) in high‐grade AVMs (P = 0.0942). Interpretation Statistical analysis of the cohort of patients with unruptured and untreated AVMs from ARUBA study showed that the graduation categories (Spetzler–Martin grades) were not associated with the outcome of subsequent stroke or death.

Medical management with interventional therapy versus medical management alone for unruptured brain arteriovenous malformations (ARUBA): final follow-up of a multicentre, non-blinded, randomised controlled trial

“…23 No formal detailed guidelines on the management of unruptured brain AVM have emerged from professional associations. Two consensus reports endorsed by the American Heart Association, the first from 2001 cited that treatment results vary considerably 24 and the most recent from 2017 that medical management alone and three often complementary methods of interventional therapy exist. 25 In summary, after mean length of follow-up 50•4 months (SD±22•9; median 48•0, IQR 35•9-71•1), medical management alone remained superior to medical management with interventional therapy for the prevention of death or symptomatic stroke in patients with an unruptured brain arteriovenous malformation in the ARUBA trial.…”

“…Further, although outcomes in the medical arm were infrequent, and few patients with Spetzler-Martin Grade III to IV AVMs were randomised in ARUBA, a recent analysis of the original ARUBA data failed to show an association between haemorrhage rate and lesion size among patients in the medical management arm. 24 The declining slope of haemorrhage events in the Kaplan-Meier curves over the 10-year follow-up for those presenting without haemorrhage in the observational Multicentre Arteriovenous malformation Research Study (MARS) also suggests that the risk of rupture in unbled patients may subside over time. 25 How some lesions seem stable for decades or life-time is still unclear.…”

“…No formal guidelines on the management of unruptured brain AVM have emerged from professional associations. Two consensus reports endorsed by the American Heart Association, the first from 2001 cited that treatment results vary considerably 24 and the most recent from 2017 that medical management alone and three often complementary methods of interventional therapy exist. 25 since the initial publication of the results of the ARUBA trial, although an AHA scientific statement recently endorsed the trial's findings.…”

Untangling the Modern Treatment Paradigm for Unruptured Brain Arteriovenous Malformations

“…They also found less impaired outcomes in the SM I and II group compared to SM III-V [ 15 ]. Stefani et al found no association in the ARUBA trial between risk of stroke or death and the SM grade of the AVM in the medical arm, prompting a call for further study into which unruptured AVMs present the highest risk of hemorrhage [ 16 ].…”

Venous Rupture Following Transcatheter Arterial Embolization for Inferior Mesenteric Type II Arteriovenous Malformation

“…Hemorrhage frequency depends on the characteristics of the AVM, such as lesion size. With brain AVM, hemorrhage reportedly occurs in about 2%-4% of untreated cases [2]. Endovascular embolization, microsurgery, and radiosurgery have been used to prevent hemorrhage [1,3,4], but no comprehensive reports have clarified the treatment for pelvic AVM.…”