[Case load and quality indicators in the treatment of abdominal aortic aneurysms].

Background: The MTL30 (mortality, transfer, length of stay) was proposed as a surrogate parameter for evaluating the quality of large and potentially complication-prone visceral surgical interventions.

Objective: The aim of this study was to find out to what extent the MTL30 can be correlated with the results of the abdominal aortic aneurysm (AAA) registry of the German Institute for Vascular Health Research (DIGG) of the German Society for Vascular Surgery and Vascular Medicine (DGG) and with the case volume of the participating hospitals.

Material And Methods: Elective endovascular abdominal aortic aneurysm repair (EVAR) was performed in 14,282 patients and open repair (OAR) in 3923 patients. Case volume of the treating hospitals, hospital mortality, length of stay and transfer to another acute care hospital were determined 30 days after the index intervention.

Results: The hospital mortality was 1.3% for EVAR and 4.9% for OAR (p = 0.000), the MTL30 was 5.0% and 14.4%, respectively (p = 0.000). For EVAR, no relationship between case volume and hospital mortality (quintile 1: 1.0%; quintile 5: 1.3%) as well as case volume and MTL30 (quintile 1: 5.3%; quintile 5: 5.3%) could be demonstrated. Also in OAR there was no significant relationship between case volume and hospital mortality (quintile 1: 5.8%, quintile 5: 3.5%; p = 0.505) and case volume and MTL30 (quintile 1: 16.4%, quintile 5: 12.2%, p = 0.110). With a hospital mortality rate of 7.2% (5-10%) the MTL30 for OAR was 17.6%. In both EVAR and OAR, the length of stay correlated significantly with hospital mortality and MTL30.

Discussion: A clear relationship between hospital case volume and hospital mortality could not be shown in the AAA registry of the DIGG. The same was true for the MTL30. It remains to be seen whether the MTL30 offers an additional benefit compared to the recording of hospital mortality and inpatient length of stay as a quality parameter.