8 - Ablation energy sources

Abstract

Radiofrequency (RF) is the most frequently used mode of ablation energy for most atrial and ventricular arrhythmias. A major limitation of standard RF ablation is the relatively small depth of tissue injury produced, which can potentially limit the success of the ablation procedure. Larger ablation lesions can be obtained by increasing the size and surface area of the ablation electrode, using an electrode material with high thermal conductivity, active or passive cooling of the electrode-tissue interface, and the use of pulsed energy. Furthermore, real-time measurement of tissue contact and contact force can help to optimize catheter-tissue contact and improve lesion formation. Alternative ablation energy sources include cryoenergy, laser, microwave, and ultrasound. Currently, two different types of cryoablation catheters are available: traditional-tip ablation catheters and balloon catheters. The cryoballoon catheter is specifically designed for pulmonary vein (PV) isolation. Catheter-based cryoablation can have specific advantages over RF energy in certain patient populations; however, it is unlikely that cryoablation will replace standard RF ablation in unselected cases. Laser energy has been used with balloon technology for PV isolation. Irreversible electroporation using pulsed field ablation is currently being investigated for catheter ablation of cardiac arrhythmias and can potentially offer several distinct advantages.