May 29, 2024
Cardiologists in Mayo Clinic's Heart Rhythm Services are performing safe and successful ablation in patients using a novel energy source. The FDA-approved pulsed field ablation (PFA) for atrial fibrillation (AFib) marks a milestone in electrophysiology.
Instead of using heat or cold energy as in traditional ablation, the PFA catheter therapy uses short bursts of high energy to affect heart tissue that causes AFib. The nonthermal energy source is also called irreversible electroporation.
The PFA therapy successfully transitioned to patient care when Mayo Clinic completed its first post-FDA approval PFA for a patient with AFib in February 2024. Mayo cardiac specialists have since used PFA to treat more than 53 patients for AFib. Mayo Clinic was one of the first of eight U.S. sites to conduct a post-approval clinical case.
Developing novel energy sources
The limitations of existing ablative therapy for AFib led to the new technology. The limitations include potentially highly morbid complications such as atrio-esophageal fistula and phrenic nerve injury. "The traditional approaches using thermal energy sources to treat AFib — radiofrequency, laser, cryo energy — all carry an associated injury risk to nearby structures, the esophagus and the phrenic nerve," says Suraj Kapa, M.D., a cardiac electrophysiologist at Mayo Clinic in Rochester, Minnesota.
The PFA technology has been in development for more than 18 years. Mayo Clinic's pioneering research in ablative therapy began under Samuel J. Asirvatham, M.D., a cardiac electrophysiologist at Mayo Clinic in Rochester, with a growing interest in developing novel energy sources to try to allow for cardiac-selective injury. "The principle underlying PFA is that, depending on the makeup of the cell membranes of different types of tissues, certain tissue may have different energy thresholds that may be 'killed' or ablated while other tissue types may be preserved," says Dr. Kapa. "Research through hundreds of preclinical trials has suggested that PFA of the heart tissue can allow for a heart tissue-specific approach to ablation while avoiding collateral injury to structures such as the esophagus or the phrenic nerve."
The research led to the development of two recently U.S.-approved systems to deliver pulsed field energy to the heart. "Both catheters are approved to treat AFib in the form of pulmonary vein isolation and have shown similar efficacy in clinical trials when compared with traditional radiofrequency ablation," says Dr. Kapa.
Benefits of PFA
Performing PFA for AFib may offer:
- Safer procedures.
- Shorter ablation times.
- Surrounding tissue protection.
- Successful results.
PFA can lead to faster procedures while reducing anesthesia time and removing some of the risks of traditional AFib ablation. "Minimizing risk and making potentially effective therapies more broadly available is critical to providing therapy to the largest number of patients," says Dr. Kapa.
It is estimated that 12.1 million people in the U.S. will be diagnosed with AFib by 2030 — more than double the number in 2010. Globally, the number of patients diagnosed with AFib is increasing.
"A growing body of evidence supports more-aggressive rhythm control with ablation, whether earlier in a patient's AFib diagnosis to achieve better long-term outcomes or in the setting of other comorbidities such as heart failure, in which ablation has shown to reduce mortality," says Dr. Kapa.
Next steps
Assessing how PFA may be used for other arrhythmias such as ventricular arrhythmias is in the works. "Some early preclinical data suggest potential superiority to current traditional thermal energy-based approaches," says Dr. Kapa.
Looking ahead, Dr. Kapa anticipates rapid growth and evolution in pulsed field therapy. "Within the next year, we expect the introduction of at least a half dozen catheters and systems utilizing pulsed field therapy, each offering new research opportunities and the potential to provide transformative, curative care for patients with arrhythmic diseases."
For more information
Refer a patient to Mayo Clinic.