Pulsed field ablation (PFA) is a non-thermal (not using extreme heat or cold) method of biological ablation (removal of structure or functionality) utilizing high-amplitude pulsed (microsecond duration) electric fields to create irreversible electroporation in tissues. [1] [2] It is used most widely to treat tumors (cancer) or cardiac arrhythmias. [3]
Atrial fibrillation frequently results from bursts of tachycardia that originate in muscle bundles extending from the atrium to the pulmonary veins. [4] Pulmonary vein isolation ablation technology has used thermal methods (radiofrequency ablation or, less often, cryoablation) to destroy pulmonary vein cells. [5] As with thermal methods of ablation, in pulsed field ablation, a thin, flexible tube (catheter) is inserted into a blood vessel in the groin and threaded up into the heart to ablate the areas of the pulmonary vein causing excessively rapid electrical signals. [6]
A major reason for recurrence of atrial fibrillation after ablation has been the belief of electrical pulmonary vein reconnection, which has not been seen for PFA. [7] In one study, atrial fibrillation recurrence in the thermal ablation group was 39% compared to 11% in the PFA group. [8] PFA can achieve pulmonary vein isolation faster than other ablation methods. [1] [8] Compared to radiofrequency ablation, PFA produces lesions of greater uniformity. [5]
Cell death following PFA is usually due to apoptosis, which is a far less damaging and inflammatory form of cell death than necrosis. [1] [3] In contrast to thermal methods of ablation, PFA specifically kills cardiomyocytes (cardiac muscle cells) without injuring surrounding tissues. [1] [2] Thermal ablation methods can damage the esophagus, phrenic nerve, and coronary vessels (as high as 5% [8] ), which are spared by PFA. [1] One study showed an overall complication rate of 0.7% for PFA and no occurrence of phrenic nerve, esophageal, or pulmonary vein injury. [9]
Because PFA is a relatively newer ablation technique, there is a lack of uniformity in the parameters for its delivery. [8] Better standardization could help reduce instances of coronary artery spasm and pulmonary artery hemorrhage, which can occur. [8] The equipment cost and lack of specialized training have limited the widespread use of PFA, making it unavailable to many patients. [8]
Recent (2024) comparisons of PFA with thermal methods have shown reduced time spent in surgery, but no superiority in safety and no better reduction of atrial fibrillation. [10] When used in areas other than the pulmonary vein, injuries have been seen. [10]
There are several commercial systems in use or pending release: