Pacemaker trial aims to beat heart failure

Technology developed by the NIHR Guy's and St Thomas' BRC is being trialled to see if it could improve outcomes for the many thousands of patients fitted with pacemakers in the UK each year.

Researchers at the National Institute for Health Research (NIHR) Guy’s and St Thomas’ Biomedical Research Centre (BRC) have used AI to develop software called the Guide CRT (Cardiac Resynchronisation Therapy) platform. The technology identifies the best location in the heart to fit a pacemaker during CRT. The software was developed in a partnership between Guy’s and St Thomas’ Department of Cardiology, biomedical engineers at King’s College London and Siemens Healthineers.

CRT is a common procedure offered to patients whose heart is not beating normally due to uncontrolled electrical activity. This means the organ struggles to circulate blood and oxygen around the body, leading to patients straining with everyday tasks causing tiredness, breathlessness and even fainting. A special type of pacemaker is fitted to ensure the contraction between the two chambers of the heart is synchronised to make it beat more effectively.

Most pacemakers have one or two wires to the heart, but CRT requires an extra wire that is more challenging to fit than the other wires. Up to one third of patients may not respond to treatment due to the lead being placed on scar tissue. The electrical pulse from the pacemaker’s lead is significantly less effective in this tissue.

The randomised study, called Tactic CRT, is taking place at a state-of-the-art catheter laboratory in St Thomas’ Hospital. During the study, half of patients will have pacemakers fitted using the MRI guidance and the other half will not in order to assess whether MRI guidance improves outcomes.

Aldo Rinaldi, consultant cardiologist and professor of cardiac electrophysiology at Guy’s and St Thomas’ and King’s College London, said:

For the first time we are able to accurately position a pacemaker in the heart which means we can avoid scar tissue in people with heart failure.

This combination of imaging technologies means we can identify exactly where we want the pacemaker leads to be in order to maximise the electrical charge they carry in order to properly re-synchronise the heart.

The first patient on the study was 68-year-old David Butler from the Isle of Sheppey (pictured above), who has had four heart attacks and has been suffering with severe breathlessness. David was transferred to Guy’s and St Thomas’ where he was offered the chance to be on the Tactic CRT study.

Since having the operation, David has said:

Each day I feel better and better and last week I was on a building site and had to climb five sets of stairs and I was able to do it while younger people with me were tired. I can’t praise the cardiology team and the nursing staff at St Thomas’ enough. They were fantastic.

Read the full article over on the NIHR Guy’s and St Thomas’ BRC website.

We are working collaboratively with colleagues in our partner organisations through the King’s Health Partners Cardiovascular Institute to support the integrated heart failure service to develop and adapt, to deliver efficient and effective care which makes a real difference to the health and wellbeing of our local population.