Outcome After Surgery for Type A Intramural Hematoma

Background: The nature and prognosis of type A intramural hematoma (TAIMH) are not well established. In this study, we evaluated the early and late outcome after surgery for this emergency condition. Methods: The ERTAAD registry included consecutive patients who underwent surgery for acute type A aortic dissection (TAAD) or TAIMH at 18 European centers for cardiac surgery. In this study, we compared the early and late outcomes of TAIMH and typical TAAD. Results: In total, 3902 consecutive patients were included in the ERTAAD registry, and 386 (9.9%) patients had TAIMH. Penn class a was present in 43.1% TAAD patients and in 34.5% TAIMH patients (p < 0.001). Among 3-month survivors, 10-year relative survival was 0.80 (95%CI 0.77-0.84) in TAAD patients and 0.76 (95%CI 0.63-0.88) in TAIMH patients. Propensity-score matching yielded 386 pairs of patients, and no significant difference was observed between the study groups in terms of early and late outcomes. In-hospital mortality rates were comparable (TAIMH 13.5% vs. TAAD 16.3%, p = 0.266). Ten-year mortality was 51.3% among TAIMH patients and 51.6% among TAAD patients (p = 0.274). TAIMH and TAAD had similar 10-year cumulative incidence rates of proximal (4.2% vs. 3.3%, p = 0.738) and distal aortic reoperations (12.6% vs. 7.6%, p = 0.779). Conclusions: This cohort study showed that the prevalence of patients with TAIMH requiring surgery is low and their risk profile is significantly different as shown by the Penn classification. The early and late outcomes of the study groups were not statistically different compared to typical TAAD when adjusted for baseline and operative variables. The relative survivals of 90-day TAIMH and TAAD survivors were low compared to the matched general population, indicating that surgically treated TAIMH demonstrated postoperative outcomes are poor and comparable to surgically treated TAAD after adjustment. Post-hoc power analysis suggested that much larger studies are needed to confirm these findings. These results are limited to TAIMH patients who underwent surgery, and this study did not address the outcome of patients who were conservatively treated.