Surgery for type A intramural hematoma: a systematic review of clinical outcomes

Background: Management of type A intramural hematoma (IMH) remains controversial, with opinions divided as to whether patients should be treated with early aggressive surgery or a more conservative approach. The present systematic review aims to evaluate the mortality and morbidities following surgery for type A IMH. Methods: Electronic searches were performed on five databases from dates of inception to December 2018. All studies with surgical outcomes for type A intramural hematoma were identified by two independent researchers and relevant data extracted. Random-effects meta-analysis of proportions or meta-analysis of means were performed to aggregate the data. Survival data were pooled using reconstructed individual patient data derived from Kaplan-Meier curves. Results: Fifteen studies with 744 patients were identified. Ten studies were from Asian countries (73% of patients). Overall mortality was 8.2% [95% confidence interval (CI): 4.6-13.9%]. Mortality from Asian centers was 5.3% (95% CI: 3.6-7.7%) and 18.9% (95% CI: 7.0-40.4%) in Western centers. Postoperative complications were poorly reported and hence not analyzable. Overall pooled survival of 343 patients from four studies at 1-, 2-, 3-, 5-, and 10-year was 91.8%, 90.2%, 89.2%, 87.7%, and 71.1%, respectively. Conclusions: There is an acceptable level of risk of death after surgery for type A IMH, though significant variations exist between results from Asian and Western centers. More detailed studies are required to clarify the controversies surrounding management of type A IMH.