Transcatheter aortic valve implantation: Association between skin flora and infective endocarditis?

Infective endocarditis is a rare but severe complication that may arise following transcatheter aortic valve implantation. Recent advances in microbiological epidemiology have highlighted staphylococci and enterococci as the primary pathogens involved.

To investigate the prevalence of these bacteria in patients' cutaneous flora before and after transcatheter aortic valve implantation procedures, and to assess the implications for antibiotic prophylaxis recommendations.

A single-centre prospective epidemiological study was conducted, enrolling patients admitted consecutively for transcatheter aortic valve implantation procedures between June 2021 and February 2022. Cutaneous samples were obtained from each patient at the puncture site of the transcatheter aortic valve implantation procedure, before and after skin detersion, and from operator hands after skin detersion.

One hundred patients were included, with a mean age of 82±6.1years, a male-to-female ratio of 0.48 and a mean body mass index of 29±4.4kg/m². Before skin detersion, cutaneous samples were positive in 58 patients; among them were coagulase-negative staphylococci (n=48, 82%, 95% confidence interval 71-91%), enterococci (n=12, 21%, 95% confidence interval: 11-33%), Staphylococcus aureus (n=2, 3%, 95% confidence interval 0-12%) and Enterobacteriaceae (n=4, 7%, 95% confidence interval: 2-17%).

Enterococci are frequently present in patients' cutaneous flora at the puncture site before skin detersion, suggesting a potential source for infective endocarditis after transcatheter aortic valve implantation. These findings support considering amoxicillin-clavulanate as antibiotic prophylaxis before transcatheter aortic valve implantation procedures to mitigate the risk of infective endocarditis associated with enterococcal colonization.