Hemorrhage Risk of Brain Arteriovenous Malformations During Pregnancy and Puerperium in a North American Cohort.

BACKGROUND AND PURPOSE: Conclusions reached in existing literature about risk of arteriovenous malformation (AVM) hemorrhage during pregnancy are controversial. This study compares the risk of hemorrhage in pregnant and nonpregnant female patients with AVM in a North American cohort. METHODS: We retrospectively reviewed female patients with AVM evaluated from 1990 to 2015. Exposure period for pregnancy and puerperium was calculated as 40 and 6 weeks, respectively, for each full-term pregnancy and 6 weeks for each abortion. Hemorrhage events and patient-years were calculated during an exposure period (pregnancy and puerperium), and a nonexposure period defined as either the interval from birth until AVM obliteration or until last follow-up after subtracting exposure period. Poisson rate ratio test was used to compare rate of hemorrhage between exposure and nonexposure periods. RESULTS: For 270 female patients with AVM, mean age was 35.0±19.6 years, and race distribution was white (n=165, 61.1%), black (n=59, 21.9%), Hispanic (n=9, 3.3%), Asian (n=6, 2.2%), and other (n=31, 11.5%). From 191 total pregnancies occurring before AVM obliteration, there were 175 (91.6%) term deliveries and 16 (8.4%) abortions. Overall annual hemorrhage rate for 149 total hemorrhages during an average of 11 097 patient-years was 1.34%. There were 140 hemorrhages in nonexposed women and 9 hemorrhages in pregnant women, translating to an annual hemorrhage rate of 1.3% in nonpregnant women versus 5.7% in pregnant women (P<0.001). Identical analysis for reproductive age patients (15-50) demonstrated a rate of 1.3% versus 7.0% (P<0.001). CONCLUSIONS: Our results conflict with those from a recent study describing no increased rate of rupture during pregnancy. This difference may reflect unique population attributes influencing brain AVM hemorrhage during pregnancy.

Treatment decision for occipital arteriovenous malformations (AVMs) to achieve hemorrhagic control while maximizing visual preservation: Our experience and review of literature.

Despite concern of hemorrhagic risk, patients with occipital AVMs are at significant risk for visual disturbances after treatment. We aim to characterize the hemorrhage risk and visual disturbance in occipital AVMs patients from our experience and literature review. We performed retrospective review of occipital AVM patients seen at our institution from 1990 to 2015. Patient characteristics were compared using multivariable logistic regression with follow-up visual disturbance as the outcome. We also systematically reviewed the PubMed database for English literature describing occipital AVMs (with exclusion of case reports). Ninety-seven patients satisfied inclusion criteria for our study. Mean age was 34.9 ±â€¯16.4 years, with 50.5% male. Thirty-one (32.0%) presented with hemorrhage, and 32 (33.0%) presented with visual disturbance. Average AVM size was 4.0 ±â€¯2.5 cm. Twenty-five (25.8%) were conservatively managed, 13 (13.4%) underwent surgery, and the rest were managed by radiosurgery (52.6%) or embolization (8.2%), with an obliteration rate of 38.9% in treated patients. During average follow-up of 5.4 years, 6 patients (6.7%) hemorrhaged yielding an annual hemorrhage rate of 1.2% for all patients, and 0.0% for surgically-treated patients. Thirty-seven (38.3%) patients experienced visual disturbance in some capacity, nineteen (21.1%) had de novo visual disturbance, fourteen of which were surgically treated patients (19.4%). Multivariable analysis reveals visual disturbance at presentation (p = .012) and microsurgery (p = .047) are significantly predictors of follow-up visual disturbance. While hemorrhage control remains the primary goal of AVM treatment, visual preservation in occipital AVMs is also a major concern. Recommending patients for microsurgery should be weighed carefully and individualized as it bears the highest risk of visual field disturbance despite most optimal hemorrhage control.