Acute Type A Dissection Repair by High-Volume Vs Low-Volume Surgeons at a High-Volume Aortic Center

Background. Previous studies suggest improved outcomes for acute type A dissections (ATAAD) treated at high-volume centers. It is unclear if outcomes are a result of individual surgeon experience or inherent resources available at high-volume centers. To explore this question, we stratified outcomes for ATAAD repair by low-volume and high-volume surgeons at a high-volume center. Methods. We reviewed our institutional experience with ATAAD between 1999 and 2016 (n = 580). To evaluate surgeon experience with ATAAD repair, we categorized surgeons as high-volume aortic surgeons (HVASs) (> 10 cases/year) or low-volume aortic surgeons (LVASs) (<= 10 cases/year). Analysis was stratified according to the following: HVAS in primary and first assist roles, HVAS as primary with LVAS as first assist, LVAS as primary and HVAS as first assist, and LVAS in both roles. Results. The total experience for HVAS and LVAS as primary surgeon for the study period was 513 and 67, respectively. Mean annual experience as primary surgeon was 15.2 cases for HVAS and 3.4 cases for LVAS. Inhospital mortality was 14.0% if an HVAS was present and 24.0% with an all-LVAS team (P = .27). After adjusting for preoperative factors, the mortality odds ratio (OR) for an all-LVAS team was 3.72 (P = .01). Conclusions. ATAAD repair by an all-LVAS team had nearly a 4-fold increase in-hospital mortality compared with an all-HVAS team. Improved outcomes at high-volume centers may be predominantly due to surgeon experience and not from center-specific resources. This study may have implications on call coverage for ATAAD repair at high-volume centers. (C) 2019 by The Society of Thoracic Surgeons