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Updated: Feb 15, 2026

Standardized Technique of Aortic Valve Re-implantation for Valve-sparing Aortic Root Replacement
Published on: December 11, 2017
A Retrospective Analysis of the Variability in Case Duration for Aortic Valve Replacement and Association With
Rodney A Gabriel1, Byron D Fergerson2, Ethan Y Brovman3
1Department of Anesthesiology, University of California, San Diego, CA; Department of Biomedical Informatics, University of California, San Diego, CA.
Objective:
Currently, there are no large-scale studies that compare differences in case duration of aortic valve replacements (AVRs). The primary objective of this study was to determine associations of hospital facility type, geographic location, case volume per year, and time of day with duration of valve replacement surgery.
Design:
Retrospective.
Setting:
Data from the National Anesthesia Clinical Outcomes Registry.
Participants:
National data from university and non-university hospitals.
Interventions:
No interventions.
Measurements And Main Results:
All AVRs from the National Anesthesia Clinical Outcomes Registry were identified from 2010 to 2014. Mean case duration for all AVRs was 360.8 ± 95.8 minutes and was presented based on facility type (university hospital, large community hospital, medium-sized community hospital, and other); US geographic region; time of day (cases performed after 5 pm and before 7 am v day shift); and case volume per year. A multivariable linear regression model was built to determine the association of various patient, procedural, and facility characteristics with case duration. University hospitals were associated with increased case duration for AVRs (p < 0.0001).
Conclusions:
With this large national database, the authors demonstrated that academic hospitals, time of day of the surgery, US region, and case volume per year for a facility are related to the case duration of AVRs.
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