Biofilm formation and migration on ventricular assist device drivelines

Yue Qu, David McGiffin, Christina Kure, Berkay Ozcelik, John Fraser, Helmut Thissen, Anton Y. Peleg

Research output: Contribution to journalArticleResearchpeer-review

2 Citations (Scopus)

Abstract

Objectives: Driveline infections remain an important complication of ventricular assist device therapy, with biofilm formation being a major contributor. This study aimed to elucidate factors that govern biofilm formation and migration on clinically relevant ventricular assist device drivelines. Methods: Experimental analyses were performed on HeartWare HVAD (HeartWare International Inc, Framingham, Mass) drivelines to assess surface chemistry and biofilm formation. To mimic the driveline exit site, a drip-flow biofilm reactor assay was used. To mimic a subcutaneous tissue environment, a tunnel-based interstitial biofilm assay was developed. Clinical HVAD drivelines explanted at the time of cardiac transplantation were also examined by scanning electron microscopy. Results: Common causative pathogens of driveline infections were able to adhere to the smooth and velour sections of the HVAD driveline and formed robust biofilms in the drip-flow biofilm reactor; however, Pseudomonas aeruginosa and Candida albicans had greater biomass. Biofilm migration within the interstitial driveline tunnel was evident for Staphylococcus epidermidis, Staphylococcus aureus, and C albicans, but not P aeruginosa. Biofilm formation by staphylococci was 500 to 10,000 times higher in the tunnel-based model compared with our exit site model. The 3-dimensional structure of the driveline velour and the use of silicone adhesive in driveline manufacturing were found to promote biofilm growth, and explanted patient drivelines demonstrated inadequate tissue in-growth along the entire velour with micro-gaps between velour fibers. Conclusions: This work highlights the predilection of pathogens to different parts of the driveline, the importance of the subcutaneous tunnel to biofilm formation and migration, and the presence of micro-gaps in clinical drivelines that could facilitate invasive driveline infections.

Original languageEnglish
Pages (from-to)491-502.e2
Number of pages14
JournalJournal of Thoracic and Cardiovascular Surgery
Volume159
Issue number2
DOIs
Publication statusPublished - Feb 2020

Keywords

  • biofilms
  • Candida albicans
  • driveline
  • interstitial biofilm
  • Pseudomonas aeruginosa
  • Staphylococcus aureus
  • Staphylococcus epidermidis
  • VAD

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