A Statewide Quality Initiative to Promote Aortic Annular Enlargement: Leading an Evolving Paradigm Shift

D. E.. Magouliotis¹, A. Can. Topcu², R. Mendoza³, R. R.. Dabir⁴, M. J.. Clark⁵, A. L.. Pruitt⁶, F. D.. Pagani⁷, B. Yang^8
1Lankenau Institute for Medical Research, Wynnewood, Pennsylvania ²Kosuyolu Education and Research Hospital, Instanbul, Istanbul ³Laval University, Quebec, Quebec ⁴Oakwood Hospital, Dearborn, Michigan ⁵Michigan Society of Thoracic and Cardiovascular Surgeons Quality Collaborative, Pinckney, Michigan ⁶Michigan Heart & Vascular Institute - CT Surgeons of Ann Arbor, Ypsilanti, Michigan ⁷University of Michigan, Ann Arbor, Michigan ⁸University of Michigan / Michigan Medicine, Ann Arbor, Michigan

Purpose: Aortic annular enlargement (AAE) represents an important adjunct strategy during aortic valve replacement (AVR) enabling implantation of a larger-size prosthesis to prevent patient-prosthesis mismatch. This review evaluates the results of a statewide quality improvement intervention (QII) that promoted the adoption of an AAE strategy, including the novel “Y-incision” technique.

Methods: A state-wide database using The Society of Thoracic Surgeons (STS) adult cardiac surgery data was used to identify patients undergoing AVR +/- AAE+/- other concomitant procedures from January 2018 to December 2023. Emergency and endocarditis cases were excluded. A QII was initiated in September 2021 and May 2023 that employed wet-lab training for surgeons in AAE techniques. The study cohort was divided into pre-QII (before wet-lab) and post-QII (after wet-lab) groups. The operative notes of all patients were reassessed to assess the accuracy of the assignment of each AAE technique. The incidence of AVR+AAE and mean valve size were the primary endpoints. Thirty-day mortality, intraoperative transfusions, and morbidity were the secondary endpoints. Additional sensitivity analyses were performed evaluating the isolated AVR+AAE and “Y-incision” technique subgroups. A two-tailed unpaired t-test and Mann-Whitney U-test were performed for parametric and non-parametric continuous data, respectively. A chi-square test was performed for categorical variables.

Results: A total of 817 patients (pre-QII: 330; post-QII: 487) were included in the study cohort. Following the review of all operative notes, 11.6% (103/889) of records audited were found to have an incorrect AEE technique and were reassigned to the QII “Y-incision” subgroup. Pre-QII and post-QII groups were similar with respect to baseline characteristics. Approximately, one third of the included patients underwent a concomitant procedure at the time of AVR+AAE. There was a significant increase in the incidence of AVR+AAE following the QII (7% vs. 19%; p< 0.001). The difference in the incidence of AVR+AAE was higher in the isolated AVR+AAE subgroup analysis (8% vs. 23%; p< 0.001). The median size of the implanted prostheses increased from a size 23 in the pre-QII group to a size 25 in the post-QII group, p< 0.001. The incidence of use of the “Y-incision” AAE technique increased significantly in the post-QII group (30% vs. 70%; p< 0.001), and was the most commonly used AAE technique in the post-QII group. No significant differences were found between the two groups with respect to intraoperative transfusions, STS-defined adverse events, length of hospital stay, 30-day readmission and mortality. The validity of the demonstrated outcomes was further supported by the sensitivity analyses.

Conclusion: A pilot QII in AAE led to a greater adoption of AAE at the time of AVR, increasing the size of the implanted AV prosthesis. The addition of AAE at the time of AVR is safe and can be performed without a significant increase in morbidity or mortality statewide.

Identify the source of the funding for this research project: Support for MSTCVS-QC is provided by Blue Cross Blue Shield of Michigan and Blue Care Network as part of the BCBSM Value Partnerships program" and the disclaimer "Although Blue Cross Blue Shield of Michigan and MSTCVS-QC work collaboratively, the opinions, beliefs and viewpoints expressed by the author do not necessarily reflect the opinions, beliefs and viewpoints of BCBSM or any of its employees.