Is standard ablation effective in patients with dilated cardiomyopathy and symptomatic atrial fibrillation?

From the Guidelines

Standard ablation can be an effective treatment option for patients with dilated cardiomyopathy and symptomatic atrial fibrillation, as it may improve symptoms and quality of life, although outcomes may vary depending on the extent of atrial remodeling and heart failure severity. According to the most recent guidelines, catheter ablation for pulmonary vein isolation (PVI) should be considered as a first-line rhythm control therapy to improve symptoms in selected patients with symptomatic atrial fibrillation 1. The procedure typically involves PVI, with additional substrate modification as needed, and should be considered particularly for patients who remain symptomatic despite optimal medical therapy, including rate or rhythm control medications.

Before ablation, patients should undergo comprehensive cardiac evaluation, including echocardiography to assess ventricular function and chamber dimensions, and optimization of heart failure therapy 1. Post-procedure, patients typically require anticoagulation for at least 2-3 months, with long-term continuation based on stroke risk factors. The effectiveness of ablation in patients with dilated cardiomyopathy is related to the complex interplay between atrial fibrillation and heart failure, as each condition can exacerbate the other. While ablation can improve symptoms and quality of life, patients should understand that multiple procedures may be necessary due to higher recurrence rates, and that maintaining sinus rhythm may help stabilize or improve cardiac function in some cases.

Key considerations for ablation in these patients include:

• Comprehensive cardiac evaluation before the procedure
• Optimization of heart failure therapy
• Anticoagulation post-procedure
• Potential need for multiple procedures due to higher recurrence rates
• Importance of maintaining sinus rhythm to stabilize or improve cardiac function. The most recent study on this topic suggests that catheter ablation can safely be performed with acceptable complication rates in patients with heart failure, and may be associated with improvement in prognostic surrogates for heart failure outcomes, including hospitalization for worsening heart failure and mortality 1.

From the Research

Effectiveness of Standard Ablation in Patients with Dilated Cardiomyopathy and Symptomatic Atrial Fibrillation

• The effectiveness of standard ablation in patients with dilated cardiomyopathy and symptomatic atrial fibrillation is a topic of ongoing research, with studies yielding mixed results 2, 3, 4, 5.
• A study published in 2015 found that standard ablation strategies, including circumferential pulmonary vein ablation, linear ablation, and complex fractionated atrial electrogram ablation, were not associated with long-term atrial fibrillation treatment success up to five years in patients with dilated cardiomyopathy 2.
• However, a 2018 study published in The New England Journal of Medicine found that catheter ablation for atrial fibrillation in patients with heart failure, including those with dilated cardiomyopathy, was associated with a significantly lower rate of a composite end point of death from any cause or hospitalization for worsening heart failure than medical therapy 3.
• Another study published in 2021 found that catheter ablation was associated with significantly lower odds of all-cause mortality at 12 months in patients with dilated cardiomyopathy and atrial fibrillation 4.
• An older study from 1993 suggested that atrial fibrillation may result in significant left ventricular dysfunction, which is reversible in some cases once the arrhythmia is controlled, and that aggressive antiarrhythmic therapy should be considered for patients initially diagnosed with dilated cardiomyopathy and atrial fibrillation 5.
• A 2016 study highlighted the importance of addressing and treating comorbid conditions, such as obesity, hypertension, and sleep-disordered breathing, to increase the likelihood of success in repeat ablation procedures 6.

Predictors of Recurrent Atrial Tachyarrhythmia

• A study found that longstanding persistent atrial fibrillation and larger left ventricular end-diastolic diameter were significant independent predictors of recurrent atrial tachyarrhythmia in patients with dilated cardiomyopathy undergoing catheter ablation 2.
• The study also found that freedom from atrial tachyarrhythmia was associated with improved heart failure symptoms, 6-minute walk distance, and left ventricular ejection fraction during long-term follow-up, but this improvement was not sustained beyond 3 years 2.