Virulence Potential of Valvular Tissue Debris after Transcatheter Aortic Valve Implantation

Abstract

Background and Aims: Peri-interventional antibiotic prophylaxis is recommended to prevent early prosthetic valve endocarditis (PVE) in transcatheter aortic valve implantation (TAVI). The individual microbial spectrum of a native degenerated heart valve may determine the incidence of early PVE. We therefore studied the spectrum of pathogens in micro tissue debris obtained from degenerated aortic valves in order to identify possible agents associated with risk of developing early PVE.

Methods: Whole genome sequencing was performed of released micro debris captured using a cerebral embolic protection (CEP) system during TAVI to determine its pathogenic molecular fingerprint. The incidence of early PVE at 12 months was compared between patients with versus without genetic microbial detection.

Results: A total of 99 patients with micro debris captured in a CEP filter were selected from a population of 1,566 patients with aortic stenosis treated by TAVI between 04/2019 and 01/2021 at the Heart Center Leipzig. Detection of 1-4 pathogens in the micro debris of the native degenerated heart valve was possible in 41% patients. The most commonly detected organisms were Enterobacter cloacae (44%) and Staphylococcus aureus (39%). Patients with genetic pathogen detection had an increased risk of developing early PVE (hazard ratio: 7.29, 95% CI: 1.43-37.17, p=0.033).

Conclusions: Whole genome sequencing of micro tissue debris extracted during TAVI was able to identify specific organisms known to commonly cause early PVE in 41% of patients. Whether these patients should be prescribed appropriate periprocedural antibiotic therapy warrants further investigation.

 

Key Words: aortic stenosis, cerebral embolic protection, microbial diagnosis, tissue debris, transcatheter aortic valve implantation, whole genome sequencing