Comparison of Epicardial Cryoablation and Irrigated Radiofrequency Ablation in a Swine Infarct Model

Abstract

Epicardial cryoablation with an 8 mm tip cryocatheter led to larger lesion volume in infarcted myocardium compared to a 3.5 mm irrigated RF catheter. This is likely related to a combination of cryoadherence, more efficient energy delivery with horizontal orientation, and lack of warming by circulating blood. Cryoablation merits further investigation as a modality for treating ventricular tachycardia of epicardial origin in humans. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1016-1023, September 2012).

Feasibility of Rapid Linear-Endocardial and Epicardial Ventricular Ablation Using an Irrigated Multipolar Radiofrequency Ablation Catheter

“…This equation was adapted from those previously used for assessment of individual radiofrequency lesion volumes. [14][15][16] Impedance and power at each linear electrode during each second of ablation was recorded by the ablation generator and was exported for statistical analysis. For focal lesions, starting and nadir impedance and maximum power were recorded manually.…”

Safety and Feasibility of Open Chest Epicardial Mapping and Ablation of Ventricular Tachycardia During the Period of Left Ventricular Assist Device Implantation

“…In our cohort, intraoperative electrophysiologic activation and/or substrate mapping was also performed along with testing for inducibility of VT postablation. Further, Chilli™ ablation catheter was used for epicardial mapping in all patients, although it is possible that cryoablation may have led to improved outcomes given its larger lesion diameter and volume . At the present time, we often use a Chilli™ ablation catheter and/or surgical cryoablation based on the operator's preference.…”

“…Further, Chilli TM ablation catheter was used for epicardial mapping in all patients, although it is possible that cryoablation may have led to improved outcomes given its larger lesion diameter and volume. 27 At the present time, we often use a Chilli TM ablation catheter and/or surgical cryoablation based on the operator's preference. Chilli TM catheter provides the advantage of real time substrate and activation mapping.…”

Epicardial Catheter Ablation Using High-Intensity Ultrasound

“…Radiofrequency lesion sizes in our study were comparable with those seen in other in vivo studies. [7][8][9] The main limitation of our study is that in vivo lesions were assessed acutely, and swine were not survived to assess lesion development over time, primarily because of cost limitations. Before development for clinical use, HIU lesions, particularly over coronary arteries, should be studied in survival studies to assess chronic lesion sizes, and delayed effects on coronary arteries.…”

“…1 However, when compared with patients with postinfarction VT undergoing ablation, patients with nonischemic cardiomyopathy (NICMP) have higher VT recurrence rates, ranging from 47% to 67% in long-term follow-up. [2][3][4] This is largely because scar in patients with NICMP is more often located in the midmyocardium or epicardium, 5,6 and the VT circuit is, therefore, difficult to reach given the limited depth of standard radiofrequency ablation (1.9-6.7 mm [7][8][9] ). Percutaneous subxyphoid pericardial access, pioneered by Sosa et al, 10 has provided another route for mapping and ablating epicardial substrate in patients with NICMP VT.…”