2026 Southeastern Residency Conference

Title: Association between Enterococcal Infective Endocarditis following a Transcatheter Aortic Valve Replacement
Authors: Felipe Gómez; Caren Azurin; Stefanie Pappas
Affiliation: Ascension Saint Thomas Hospital West, Nashville, TN
Introduction Transcatheter aortic valve replacement (TAVR) is standard therapy for severe aortic stenosis. A severe complication is infective endocarditis (IE), predominantly caused by Enterococcus species (historically 24–34% of cases) due to patient comorbidities and groin contamination during transfemoral access. Our institution’s current prophylaxis protocol utilizes cefazolin, which lacks enterococcal coverage. The primary objective was to assess the association between surgical antibiotic prophylaxis and enterococcal IE risk following TAVR. Secondary objectives evaluated the time to infection, all-cause inpatient mortality, and surgical intervention rates.
Methods A single-center, retrospective observational review was conducted on 102 patients (≥18 years) who underwent TAVR between January 2023 and December 2024. Exclusions included prior antibiotic therapy, concurrent infections, or incarcerated status. Data was collected via REDCap. Statistical analysis utilized Fisher’s exact test for categorical variables and the Mann-Whitney U test for continuous data, with significance defined as p<0.05.
Results Of the 102 patients evaluated, 5 (4.9%) developed IE. Enterococcus spp. was the predominant pathogen, responsible for 80% (4 of 5) of cases. All patients who developed IE received 2 grams of cefazolin prophylaxis. Consequently, no significant association was found between prophylactic choice and IE (p=1.000) due to the near-universal administration of cefazolin. The mean time from surgery to enterococcal IE onset was 497.8 days. The infection rate was 6.4% for transfemoral access versus 0% for the carotid approach (p=0.585). Among the patients who developed IE, mortality was 0%, while 40% (n=2) required surgical intervention.
Discussion & Conclusion Enterococcus caused 80% of TAVR-related IE cases in this cohort, significantly exceeding historically reported rates. The data indicates that current institutional prophylaxis with cefazolin leaves a critical coverage gap for this specific population. Additionally, the higher infection rate in the transfemoral group highlights the risk of groin-sourced enterococcal inoculation. Despite limitations surrounding sample size and retrospective design, these findings provide actionable clinical evidence supporting the revision of the institutional TAVR protocol to incorporate agents with enterococcal activity (e.g., ampicillin/sulbactam) to target the predominant pathogen and improve patient outcomes.