Late Outcomes of Surgery Versus Medical Therapy in Patients With Type A Aortic Intramural Hematoma: Meta-Analysis of Reconstructed Time-to-Event Data

The effect of an initial surgical approach (in comparison with initial medical therapy) in acute type A intramural hematoma remains insufficiently explored. We designed a pooled analysis of Kaplan-Meier-derived individual patient data from studies with follow-up for overall survival (all-cause death). Restricted mean survival time was calculated to evaluate lifetime gain or loss. The Risk of Bias in Non-Randomized Studies of Interventions tool (ROBINS-I) was used to assess risk of bias. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) was applied to assess certainty of evidence. Eight studies met our eligibility criteria, including a total of 654 patients (311 patients treated with surgery and 343 patients treated with medical therapy alone). All the studies were non-randomized and observational. The median follow-up was 4.6 years (interquartile range 1.0 to 7.7). Patients who underwent surgery had a significantly lower risk of mortality compared with patients receiving medical therapy alone (hazard ratio 0.51, 95% confidence interval 0.35 to 0.74, p <0.001). The restricted mean survival time was overall 1.1 years greater with surgery compared with medical therapy, and this difference was statistically significant (p <0.001), which means that surgery is associated with lifetime gain. The overall risk of bias (ROBINS-I) was considered moderate-to-serious and the certainty of evidence (GRADE) was deemed to be low. In conclusion, in the overall follow-up, surgery as the initial approach was associated with better late survival and lifetime gain in comparison with medical therapy alone in the setting of acute type A aortic intramural hematoma; however, high-quality randomized trials are warranted to establish the efficacy of the surgical strategy.