Keeping heart lines clean

Professor David McGiffin, Professor Anton Peleg, Dr Yue Qu

The ventricular assist device (VAD), a mechanical pump that helps the heart move blood, can be a vital therapy for end-stage heart disease. However, infections on the ‘driveline’, the cable connecting the internal pump to the batteries and computer controlling the device carried outside the body, can cause serious complications.

Monash University microbiologists Dr Yue Qu and Professor Anton Peleg are part of a collaboration that has gained a grant from the Medtronic External Research Program to further research into driveline infection.
Medtronic Inc. is the world’s leading medical device company. The one-year grant also comes with custom-made VAD drivelines, which are otherwise hard to access, for this research.

Dr Qu is an expert in biofilm-related medical device infections based at the Monash Biomedicine Discovery Institute (BDI). Professor Peleg, a world-renowned infectious diseases and microbiology clinician-researcher, is Head of Department of Infectious Diseases at The Alfred Hospital, and a researcher at both the Monash Central Clinical School and Monash BDI. These two researchers work closely with Professor David McGiffin, an Alfred Hospital surgeon, researcher and a pioneer in the field of heart-lung transplant; and Dr Helmut Thissen from CSIRO Manufacturing, an expert in polymeric biomedical materials and the control of bio-interfacial interactions.

The team, which has published several joint research papers, attracted the attention of Medtronic after Professor Peleg gave two oral presentations at the International Society of Heart and Lung Transplantation conference in Florida in April 2019 about their latest research, and also because of a paper on driveline infections the team had published the month previous. The paper, appearing in the well regarded Journal of Thoracic and Cardiovascular Surgery had prompted a number of phone calls from potential industry partners.

“What we are trying to do now is to establish a very good understanding of how bacteria form the structure called biofilms, how they migrate from outside the body along the driveline, get into deep tissue and cause severe infection,” he said.

Once a microbial biofilm is established on the surface of a driveline, the embedded bacteria/fungi become extremely resistant to antimicrobial treatment and the human immune system.

“When we understand how they work then we can develop a strategy to prevent infection,” Dr Qu said.

He said VADs are being used successfully in Australia and widely around the world as a bridge to heart transplant or as a ‘destination therapy’ – an alternative to heart transplantation for people with end-stage heart failure but who are ineligible for transplant.

Laboratory work for the project is being carried out in Professor Peleg’s laboratory at the Monash BDI, supported by the Alfred Hospital’s Department of Cardiothoracic Surgery & Transplantation, and Department of Infectious Diseases. The Alfred Hospital implants the most ventricular assist devices in patients in Australia.