An additional treatment performed in conjunction with catheter ablation reduced the risk of recurrence in patients with persistent atrial fibrillation. This is shown in a randomised study led by researchers at Karolinska Institutet and published in JAMA. The treatment also improved patients' quality of life without increasing the risk of serious complications.
Atrial fibrillation is the most common cardiac arrhythmia and increases the risk of conditions such as stroke and heart failure. An established treatment is catheter ablation, in which physicians use thin catheters to create small scars in the heart tissue to block the electrical signals that cause the arrhythmia. Despite treatment, many patients with the more difficult-to-treat form, persistent atrial fibrillation, experience recurrence.
Researchers at Karolinska Institutet and Karolinska University Hospital have now investigated whether outcomes can be improved by also treating areas in the heart's left atrium that show signs of fibrosis or scarring. These areas are identified as so-called low-voltage zones, where the electrical signal is weaker than in healthy heart tissue.
The study was conducted at five Swedish hospitals and included 209 patients with persistent atrial fibrillation and clearly defined low-voltage zones in the left atrium. Participants were randomly assigned to either standard treatment with pulmonary vein isolation or pulmonary vein isolation combined with targeted treatment of the low-voltage zones. The patients were followed for twelve months.
Better prognosis with a personalised strategy
The results showed that 67.6 per cent of patients who received the combination treatment were free from atrial arrhythmias at follow-up, compared with 37.4 per cent of patients who received standard treatment. The difference corresponds to approximately 30 percentage points.
"Patients with persistent atrial fibrillation and signs of extensive remodelling of the atria often have poorer treatment outcomes than other patients. Our results suggest that a more personalised ablation strategy may improve the prognosis for this group," says Nikola Drca , researcher at the Department of Medicine, Huddinge , Karolinska Institutet, and principal investigator of the study.
Improved quality of life
"We also found that patients who received the additional treatment reported greater improvements in health-related quality of life. At the same time, we could not identify any statistically significant difference in serious complications between the groups," says Astrid Paul-Nordin , affiliated researcher at the same department and the study's first author.
The study, IDEAL-AF, was conducted by researchers at Karolinska Institutet and Karolinska University Hospital in collaboration with Linköping University Hospital, Sahlgrenska University Hospital, Danderyd Hospital and Umeå University Hospital.
The research was funded by, among others, the Swedish Research Council, the Swedish Heart-Lung Foundation, the Centre for Innovative Medicine (CIMED), ALF funding and the Åke Wiberg Foundation. Several of the researchers report receiving compensation from, or having research collaborations with, companies that develop medical technology for cardiac rhythm treatment. Coala Solutions AB provided the rhythm monitoring devices used in the study but had no role in the conduct, analysis or publication of the study.
Publication
Low-Voltage Ablation in Persistent Atrial Fibrillation: The IDEAL-AF Randomized Clinical Trial
Paul Nordin A, Charitakis E, Carnlöf C, Åkerström F, Saluveer O, Almroth H, Karlsson LO, Hassel Jönsson A, Herczku C, Tapanainen J, Höglund N, Svennberg E, Braunschweig F, Bourke T, Schwieler J, Bastani H, Saygi S, Asaad F, Türkmen Y, Jensen-Urstad M, Drca N. JAMA, online 30 August 2026, doi: 10.1001/jama.2026.17274.
