Large study shows pulsed field ablation technique safe and effective for atrial fibrillation treatment
A groundbreaking study involving over 17,000 patients has demonstrated the safety of pulsed field ablation (PFA) for treating atrial fibrillation. The MANIFEST-17K trial, led by researchers from the Icahn School of Medicine at Mount Sinai, provides compelling evidence that this novel technique avoids many of the complications associated with traditional thermal ablation methods.
Atrial fibrillation (AF) affects millions worldwide, causing irregular heartbeats and increasing the risk of stroke. Catheter ablation has long been a standard treatment option, but conventional thermal-based methods carry risks of collateral damage to surrounding tissues. The advent of PFA represents a significant leap forward in addressing these concerns.
Senior author Vivek Reddy, MD, The Leona M. and Harry B. Helmsley Charitable Trust Professor of Medicine in Cardiac Electrophysiology at the Icahn School of Medicine at Mount Sinai
Dr Vivek Reddy, senior author and Professor of Medicine in Cardiac Electrophysiology at Icahn Mount Sinai, emphasised the importance of the findings: “MANIFEST-17K provides confidence that, unlike conventional thermal ablation, PFA with the pentaspline catheter does not cause the most feared complication of AF ablation –oesophageal damage – nor does it cause pulmonary vein stenosis or persistent injury to the diaphragm.”
Understanding pulsed field ablation
PFA utilises short, high-energy electrical pulses to create precise lesions in cardiac tissue, unlike the temperature-based approaches of radiofrequency ablation and cryoablation. This novel mechanism allows for greater precision and potentially reduced risk to adjacent structures.
The study, published in Nature Medicine [1], analysed data from 17,642 patients who underwent PFA procedures at 106 centres in 2021. All procedures employed the pentaspline PFA catheter, currently the most widely used PFA device globally.
Safety profile surpasses expectations
The results of the MANIFEST-17K trial are remarkably promising. Researchers observed no instances of energy-specific complications typically associated with thermal ablation techniques. Notably absent were cases of oesophageal damage, pulmonary vein stenosis, or persistent phrenic nerve injury.
The overall major complication rate was a mere 1%, with specific rates as follows: pericardial tamponade occurred in 0.36% of cases, vascular complications in 0.30%, stroke in 0.12%, and death in 0.03% of patients. These figures compare favourably to historical data from conventional ablation techniques, suggesting a significant improvement in patient safety.
Unexpected findings
Whilst the safety profile of PFA is overwhelmingly positive, the study did uncover two unexpected complications. Coronary arterial spasm was observed in 0.14% of cases, and haemolysis-related acute renal failure necessitating haemodialysis occurred in 0.03% of patients.
Dr Reddy acknowledged the need for ongoing surveillance: “While we should continue to remain vigilant to identify any other rare complications of PFA that may be identified in the future, these favourable safety outcomes in over 17,000 patients increase our confidence in the use of this PFA catheter technology.”
Implications for clinical practice
The MANIFEST-17K study provides robust evidence supporting the safety of PFA in a large, diverse patient population. This data is likely to accelerate the adoption of PFA as a first-line treatment option for many patients with atrial fibrillation.
The absence of thermal-related complications, particularly oesophageal injury, addresses one of the primary concerns that has historically limited the widespread use of catheter ablation in AF patients. As confidence in the safety of PFA grows, more patients may have access to this potentially curative treatment earlier in their disease course.
Limitations and future research
While the MANIFEST-17K trial offers compelling safety data, it is important to note its retrospective, observational design. Prospective, randomised studies comparing PFA directly to conventional ablation techniques will be crucial to definitively establish its superiority.
Additionally, long-term efficacy data will be necessary to fully understand the role of PFA in AF management. Future studies should focus on assessing recurrence rates, quality of life improvements, and potential cost-effectiveness compared to traditional ablation methods.
Conclusion
The MANIFEST-17K study represents a significant milestone in the evolution of atrial fibrillation treatment. By demonstrating the safety of pulsed field ablation in a large, real-world patient cohort, this research paves the way for a paradigm shift in how we approach catheter ablation for AF.
Reference:
- Ekanem, E., Neuzil, P., Reichlin, T., et. al. (2024). Safety of pulsed field ablation in more than 17,000 patients with atrial fibrillation in the MANIFEST-17K study. Nature Medicine. https://doi.org/10.1038/s41591-024-03114-3
