Impact on Outcome of Abdominal Aortic Aneurysm Repair Centralization: An Early Experience in Public Health System

Abstract

Introduction: Several studies described that high volume centers have better outcomes than low volume centers in the treatment of abdominal aortic aneurysm (AAA). However, the real benefit of centralization of this pathology has not been well demonstrated yet. The aim of this study is to analyze the impact of centralization on AAA treatment outcomes in Catalonia (Spain). Methods: Data were collected from official national registries related to AAA treated with endovascular aneurysm repair (EVAR) or open repair (OR) in a ten year period. Two time periods were selected for comparison: before centralization (from January 2008 to May 2015) and after complete centralization (from June 2015 to December 2017). Primary endpoint was to determine the influence of centralization in terms of in-hospital mortality and length of stay (LOS) after treatment of intact AAA (iAAA) and ruptured AAA (rAAA), in low and high volume centers. Data are presented as either mean values with standard deviations (SD) within parentheses or percentages, and compared with Pearson Chi Square or T-Test for independent samples. Results: In overall, 4236 AAA treatments were included (89.8% iAAA, 10.2% rAAA). After centralization a significant decrease in overall mortality in both iAAA and rAAA repairs was observed (4.1% vs 1.9%, p = .001; 52.8% vs 37.2%, p = .003, respectively). In spite of an increase in EVAR proportion after centralization (62.8% vs 77.5%, p < .001 for iAAA and 35.4% vs 67.4% for rAAA, p < .001), mortality reduction in iAAA was significant for OR (7.8% vs 3.3% , p = .014), but not for EVAR (1.9% vs 1.5%, p = .412). Overall LOS decreased as well, mainly in iAAA (9.54 ± 10.93 vs 7.4 ± 12.07, p < .001). Also, regarding only high volume centers, a significant reduction in mortality after centralization for both iAAA (3.8% vs 1.9%, p = .004) and rAAA repair (52.3% vs 37.0%, p = .004) was observed. Conclusion: After centralization, in-hospital mortality significantly decreased for iAAA and rAAA repairs, mainly for OR. LOS was also significantly decreased. Furthermore, high volume centers experienced an improvement in their own results after centralization. Thereafter, centralization for AAA repair into high-volume reference centers should be considered in public health systems. Disclosure: none