Women left behind by treatment to get heartbeat back in rhythm
New research has highlighted a significant gender treatment gap for atrial fibrillation (AF), a common heart rhythm disorder which is projected to increase by 60 per cent over the next 15 years and dramatically heightens the risk of stroke and death.
The study led by Professor Peter Kistler, Head of Clinical Electrophysiology at the Baker Institute and the Alfred hospital, and his PhD fellow Dr Hari Sugumar, showed that a potential cure for AF — known as catheter ablation — is significantly less effective for women than men.
“Although AF is more common in men, women make up a significant proportion of the people with ‘persistent’ AF, those who experience longer lasting symptoms despite medication or other treatments,” Professor Kistler said.
“Women’s lives are at risk and we must get better at treating them. There hasn’t been a new drug developed for AF for more than 30 years. Most of the research and development has gone into catheter ablation. But the success rate for these procedures is sitting at around 60 to 70 per cent, and our study shows that figure is even lower for women with persistent AF.”
People with AF have a three-fold increased risk of heart failure, and are five times more likely to suffer a stroke than those without AF.
Professor Kistler’s study published recently in the journal Heart Rhythm looked at 281 patients — 30 per cent female and 70 per cent male — who had received more than one cardiac ablation procedure to treat AF.
It found that while 57 per cent of men in the group were free from atrial arrhythmias on follow-up, just 38 per cent of women were.
The data also showed that pulmonary vein re-connection — a key marker in treatment — was far less likely in women and the number of pulmonary veins reconnected was much smaller in women than in men.
“We must shift priorities away from a focus on AF as a predominately male condition, to examine the gender differences in its mechanisms and close the treatment gap,” Professor Kistler said.
Professor Kistler has just received funding from the Baker Department of Cardiometabolic Health, recently established at Melbourne Medical School, to support a trial of a new ablation treatment and test if it can generate better results.
Cardiac ablation works by scarring or destroying tissue in the heart that triggers or sustains an abnormal heart rhythm. It’s commonly used to help people with arrhythmias where medication is not working as it should be or is producing negative side effects.
“We want to improve the success of this procedure and have developed a new method that targets a bigger area in the heart’s left atrium. It’s a more time consuming procedure, but we’re hoping to show it can produce a better success rate in patients,” Professor Kistler said.
The CAPLA randomised controlled trial will monitor about 400 AF patients, half of who receive the regular ablation procedure, the other half who receive what Professor Kistler’s team is proposing as a new gold standard. Participants are then provided with the latest in mobile ECG technology, so researchers can intensively monitor their heart rhythm in the months following the procedure.
The trial will be conducted internationally across five sites in Victoria as well as sites in Canberra, Adelaide, the UK and Canada, over the next two years.
Professor Kistler said there were enormous benefits in running the trial through the new partnership between the Baker Institute and University of Melbourne.
“This is a multi-centred study, and to look at outcomes across a wide demographic area you need a broad team contributing patients and expertise globally,” he said.