Cardiac Breakthrough Could Offer Lifesaving Treatment to More Patients

A new study suggests that an implantable defibrillator could help more people with heart problems. This device, called an implantable cardioverter-defibrillator (ICD), is usually only given to patients with severe heart issues. However, the new research shows it might also benefit those with milder heart dysfunction and scarring.

The trial lasted over ten years. It found that ICDs could help some patients under 70 years old. These patients had mild-to-moderate heart dysfunction and scarring.

Expanding Treatment Options

Professor Joseph Selvanayagam from Flinders University led the study. He presented the findings at the 2026 European Society of Cardiology Congress. The results were also published in the Journal of the American Medical Association (JAMA).

The trial included 18 sites in Australia, Germany, and the UK. It looked at whether ICDs could help a broader group of patients. An ICD is a small device that corrects dangerous heart rhythms. These rhythms can lead to sudden cardiac death.

Current guidelines only recommend ICDs for patients with severely reduced heart function. But Professor Selvanayagam's team studied patients with mild-to-moderate heart dysfunction. This meant their left ventricular ejection fraction (LVEF) was between 36% and 50%. They also had heart muscle scarring, found by cardiac MRI. The goal was to see if an ICD could reduce sudden cardiac death or serious irregular heartbeats in this group.

Key Findings for Younger Patients

The study found that ICDs did not significantly reduce the main problem across all age groups. This main problem was a combination of sudden cardiac death and serious irregular heartbeats.

However, a specific analysis of patients younger than 70 showed a significant reduction in this problem. The researchers also found that ICDs reduced sudden cardiac death across the entire study group. This was a secondary finding.

This is the first trial of its kind. It helps doctors decide about ICDs for patients with heart scarring and an LVEF of 36-50%.

Professor Selvanayagam explained that an ICD is like having a personal paramedic for your heart. He noted that many people who die suddenly from heart events do not have severe heart dysfunction. This means they currently don't get offered an ICD.

He believes this research could save lives. He suggests that if you have mild-to-moderately reduced heart function due to a heart attack or other heart disease, you should get a cardiac MRI. If the MRI shows significant scarring, you should talk to your cardiologist about an ICD, especially if you are under 70.

Deep Dive & References

Cardiovascular Magnetic Resonance to Guide Defibrillator Implantation for LVEF of 36% to 50%: The CMR GUIDE Randomized Clinical Trial - JAMA, 2026