Ground-breaking clinical trial aims to reduce sudden cardiac deaths

A landmark clinical trial that could reduce deaths from sudden cardiac arrests has opened in Southampton.

The BRITISH trial is now recruiting at University Hospital Southampton (UHS), with sites in Portsmouth and Aberdeen opening soon.

The trial is funded by £1.8m from the British Heart Foundation. It aims to work out which patients could benefit from having an implantable cardioverter defibrillator (ICD) fitted under the skin in their chest.

Consultant cardiologists Dr Andrew Flett and Professor Nick Curzen at UHS are leading the trial. It is co-ordinated by the NIHR Southampton Clinical Trials Unit (CTU).

A world-first trial

Non-ischemic cardiomyopathy (NICM) is a common type of heart failure which can lead to abnormal heart rhythms. Sudden cardiac arrests are a major cause of death in patients with the condition.

ICDs are small devices fitted in a patient’s chest. They can stop abnormal rhythms and treat cardiac arrest by delivering an electric shock to the heart.

Current guidelines look at how well the heart is pumping to decide which patients should get an implant, but this may not be the best method. Many patients who have an ICD fitted will never benefit from it.

“As with any surgical procedure, there is a risk of complications from having an ICD fitted,” explained Dr Andrew Flett, Chief Investigator of the BRITISH trial.

“We therefore want to find a better way to assess which patients will truly benefit from one of these devices before it is fitted.

“There is evidence that scar tissue in the heart muscle may be the cause of dangerous heart rhythms for patients with NICM. This will be the first ever trial to look at whether scar tissue can predict who should be fitted with an ICD.”

First patients

The BRITISH trial is now open to patients at UHS, who are sponsoring the trial.

Researchers in 35 UK hospitals will recruit over 2,500 NCIM patients. They can take part if an MRI scan has detected evidence of scarring in the heart.

Participants will be randomly allocated into one of two trial arms. One half will be fitted with an ICD and the other half will be fitted with an implantable loop recorder (ILR). The ILR device monitors heart activity so that the team can review abnormal rhythms but does not shock the heart.

“The trial will also involve a registry of patients who do not have scar tissue and are therefore treated according to current guidelines,” said Anna Cebula, Trial Manager at Southampton CTU.

“This means we will be able to review data from all three groups and compare patient outcomes to establish whether scar tissue is an indicator of who should have an ICD.”

Dr Flett added: “The ultimate goal of any research is to improve treatment for our patients. The BRITISH trial will inform UK and international guidelines for the treatment of NICM heart failure.

"If the BRITISH trial is successful, it could identify a group of patients who we know will benefit from ICDs and reduce unnecessary procedures for patients who don’t need them. This will help ensure cost effective use of our health service in the future.”