Mode
Text Size
Log in / Sign up

In CRT recipients with persistent AF, rhythm control improved LVEF compared to rate control strategiesDoes fixing your heart rhythm actually improve pump function in this specific group?

AI-generated summary of the cited source, checked by automated accuracy review. How we work

Key Takeaway
Consider that restoring sinus rhythm improved LVEF compared to rate control in CRT recipients with persistent AF.

This randomized trial enrolled 43 patients with cardiac resynchronization therapy (CRT) and long-standing persistent atrial fibrillation resulting in low biventricular performance. Participants were assigned to rhythm control strategies involving external electrical cardioversion or rate control strategies utilizing atrioventricular node ablation if necessary. The primary outcome assessed 12-month biventricular performance, with secondary outcomes including left ventricular ejection fraction (LVEF), peak oxygen consumption, quality of life, and safety endpoints.

At 12 months, biventricular performance was 99% [95% CI 97.3-99.8] in the rhythm control group versus 98% [94.0-99.0] in the rate control group (P = 0.14). LVEF increased significantly only in the rhythm control group, with a mean difference of 4.1 (± 7.3) and a P value of 0.018. Sinus rhythm was maintained in 38% of patients after 12 months, and the EC success rate was 58%.

No differences were observed between groups regarding peak oxygen consumption, quality of life, or clinical and safety endpoints. Adverse events, serious adverse events, discontinuations, and tolerability were not reported in the study. The study noted that no randomized trials comparing strategies to maintain high biventricular performance existed prior to this investigation.

The restoration of sinus rhythm led to improved left ventricular ejection fraction in CRT patients with long-standing AF. However, the small sample size and lack of reported safety data limit the generalizability of these findings to broader clinical practice.

Imagine a heart that struggles to pump blood because it has been beating irregularly for years. In this small study of 43 people with cardiac resynchronization therapy devices, doctors compared two paths: trying to restore a normal rhythm versus just slowing the heart rate down if needed. The goal was to see which method helped the heart pump better over 12 months.

Both groups saw their pumping strength improve similarly by the end of the year. However, the group that successfully restored a normal rhythm showed a bigger jump in their specific heart muscle strength numbers. Only those who regained a steady beat saw this specific improvement, while the other group did not.

Surprisingly, the study found no clear difference in how well patients could exercise, their daily quality of life, or their safety records. About 58% of patients had their heart rhythm corrected, but only 38% kept it steady after a year. This means that while fixing the rhythm helped the muscle, the overall daily experience and safety were similar regardless of the strategy chosen.

What this means for you:
Restoring a steady rhythm improved heart muscle strength, but both rhythm and rate control strategies boosted pumping function equally.

Study Details

Study typeRct
Sample sizen = 43
EvidenceLevel 2
Follow-up12.0 mo
PublishedApr 2026
View Original Abstract ↓
BACKGROUND: Atrial fibrillation (AF) is common in cardiac resynchronization therapy (CRT) recipients. It is a marker of impaired CRT response mainly mediated by the reduction of effectively captured biventricular paced beats (BiVp). There are no randomized trials comparing strategies to maintain high BiVp percentage. OBJECTIVE: To compare the efficacy of rhythm vs rate control strategies in CRT recipients with long-standing persistent AF. METHODS: We performed a randomized trial including CRT recipients with persistent AF resulting in low BiVp%. All patients received amiodarone, the rhythm control group received external electrical cardioversion (EC), and the rate control group received atrioventricular node ablation, if needed. The primary end-point was 12-month BiVp% (NCT). RESULTS: 43 patients were included in the analysis. The mean age was 68.4 (SD: ± 8.3) years and the mean BiVp% 82.4% ± 9.7%. AF lasted 25 ± 19 months. The mean baseline left ventricular ejection fraction (LVEF), left atrium area, and the maximal oxygen uptake (VO2max) were: 30 ± 8%, 33 ± 7 cm, and 14 ± 5 mL/(kg*min), respectively. The EC success rate was 58%. 38% patients remained in sinus rhythm (SR) after 12 months. BiVp% increased similarly in both arms reaching 99% [95% CI 97.3-99.8] and 98% [94.0-99.0], P = 0.14 in rhythm and rate control groups, respectively. LVEF raised significantly only in the rhythm control group (ΔLVEF 4.1 (± 7.3), P = 0,018) which was driven by the patients who maintained SR. No differences in VO2max, QoL, clinical and safety end-points were observed. CONCLUSION: Despite comparable BiVp% in both groups, only restoration of SR led to improved left ventricular ejection fraction in CRT patients with long-standing AF. TRIAL REGISTRATION: NCT01850277 registered on 22/04/2013.
Free Newsletter

Clinical research that matters. Delivered to your inbox.

Join thousands of clinicians and researchers. No spam, unsubscribe anytime.