Pulmonary Vein Isolation With Optimized Linear Ablation vs Pulmonary Vein Isolation Alone for Persistent AF The PROMPT-AF Randomized Clinical Trial

Caihua Sang, MD; Qiang Liu, MD; Yiwei Lai, MD; et al.

By: Ann Garfield

5 Key Take Aways

1. Adding EIVOM and linear ablation to PVI significantly improved atrial arrhythmia freedom in persistent AF patients, with a 9.2% higher success rate than PVI alone.
2. The combination approach led to longer procedure and fluoroscopy times but resulted in better arrhythmia control and fewer repeat procedures.
3.  EIVOM facilitated durable mitral isthmus block and enhanced ablation success by eliminating epicardial conduction, improving lesion durability.
4. Despite improvements, technical challenges such as undetectable VOM and anatomical barriers, limited some ablation success, highlighting the need for refined techniques.
5. The trial’s monitoring method using weekly ECG patches may have underestimated atrial arrhythmia recurrence compared to implantable loop recorders, limiting result precision.

Persistent atrial fibrillation (AF) remains a challenging condition for clinicians, as it is associated with significant morbidity, increased healthcare burden and reduced quality of life.  Pulmonary vein isolation (PVI) is a cornerstone treatment for managing AF through catheter ablation, particularly effective for paroxysmal AF.  However, in cases of persistent AF, where arrhythmias last longer and are more resistant to therapy, the efficacy of PVI alone is often limited.  The PROMPT-AF randomized clinical trial investigated whether combining PVI with optimized linear ablation and ethanol injection into the vein of Marshall (EIVOM) could improve outcomes for patients with persistent AF.

The study found that at the 12-month follow-up, patients who received PVI along with linear ablation and EIVOM demonstrated a significant reduction in arrhythmia recurrence. Approximately 70.7% achieved freedom from atrial arrhythmias lasting more than 30 seconds, compared to 61.5% in the group that underwent PVI alone.  Despite the reduction in recurrence, secondary outcomes, including overall AF burden and patient-reported quality of life, showed no meaningful differences between the groups.  Moreover, the combined intervention came at the cost of longer procedures and increased procedural complications, particularly a higher incidence of pericarditis and pericardial effusion.

The trial was conducted as a multicenter, randomized controlled study at 12 tertiary centers in China, involving 498 patients with drug-refractory persistent AF lasting more than three months. All participants were undergoing first-time ablation and were randomized into two groups: one receiving standard PVI and the other receiving PVI with additional linear ablation and EIVOM. The linear ablation targeted specific areas, including the mitral isthmus, left atrial roof, and cavotricuspid isthmus.  To improve success rates, ethanol injection was used to modify the vein of Marshall.  Patients were followed for 12 months with a combination of wearable single-lead ECG monitors, symptom-triggered ECG recordings, and periodic Holter monitoring,

The primary outcome of the trial was assessed using survival analysis techniques.  The freedom from atrial arrhythmias lasting over 30 seconds without the use of antiarrhythmic drugs served as the primary endpoint.

The PROMPT-AF trial’s large sample size, randomization, and comprehensive monitoring strengthened its reliability and validity.  By focusing on persistent AF, it addressed a significant clinical gap in ablation strategies.  However, its increased procedural complexity and risks highlight limitations that require careful consideration in practice.

However, the trial has limitations.  The increased procedural complexity and duration associated with the combined approach may limit its feasibility in routine clinical practice, especially in centers with limited resources or less experienced operators.  Furthermore, the higher complication rates raise concerns about patient safety and the trade-offs involved in achieving incremental benefits.  Another limitation is the lack of improvement in secondary outcomes, such as AF burden and quality of life, which questions the overall clinical significance of the observed reduction in arrhythmia recurrence.  The study’s 12-month follow-up period, while sufficient to demonstrate short-term efficacy, does not provide insights into long-term outcomes, including the durability of arrhythmia control and potential late complications.  Lastly, the exclusive focus on Chinese tertiary centers may limit the generalizability of findings to other populations and healthcare systems with differing patient demographics and procedural practices.

The findings of the PROMPT-AF trial have important implications for clinical practice.  For patients with persistent AF, adding linear ablation and EIVOM to PVI offers a modest reduction in arrhythmia recurrence but at the cost of increased procedural time and complications. Clinicians must carefully consider patient selection, weighing the potential benefits against the procedural risks.  The lack of improvement in AF burden and quality of life suggests that the combined approach may not substantially enhance the patient experience.  As newer technologies, such as pulsed field ablation emerge with the promise of greater safety and efficacy, future studies should explore their integration into the management of persistent AF.

In conclusion, the PROMPT-AF trial provides evidence that supplementing PVI with optimized linear ablation and EIVOM can modestly improve arrhythmia control in persistent AF.  However, the increased complexity, risks, and limited impact on secondary outcomes highlight the need for continued innovation in AF management strategies.  Longer-term studies and broader patient populations will be essential to refining these approaches and determining their role in clinical practice.

Bibliography

Sang, MD C, Liu, MD Q, Lai, MD Y. Pulmonary Vein Isolation With Optimized Linear Ablation vs Pulmonary Vein Isolation Alone for Persistent AF The PROMPT-AF Randomized Clinical Trial. Jama.