TY - JOUR
T1 - Epicardial Catheter Ablation Using High-Intensity Ultrasound
T2 - Validation in a Swine Model
AU - Nazer, Babak
AU - Salgaonkar, Vasant
AU - Diederich, Chris J.
AU - Jones, Peter D.
AU - Duggirala, Srikant
AU - Tanaka, Yasuaki
AU - Ng, Bennett
AU - Sievers, Richard
AU - Gerstenfeld, Edward P.
N1 - Publisher Copyright:
© 2015 American Heart Association, Inc.
PY - 2015/12/1
Y1 - 2015/12/1
N2 - Epicardial radiofrequency catheter ablation of ventricular tachycardia remains challenging because of the presence of deep myocardial scar and adjacent cardiac structures, such as the coronary arteries, phrenic nerve, and epicardial fat that limit delivery of radiofrequency energy. High-intensity ultrasound (HIU) is an acoustic energy source able to deliver deep lesions through fat, while sparing superficial structures. We developed and tested an epicardial HIU ablation catheter in a closed chest, in vivo swine model. Methods and Results-The HIU catheter is an internally cooled, 14-French, side-facing catheter, integrated with A-mode ultrasound guidance. Swine underwent percutaneous subxyphoid epicardial access and ablation with HIU (n=10 swine) at 15, 20, and 30 W. Compared with irrigated radiofrequency lesions in control swine (n = 5), HIU demonstrated increased lesion depth (HIU 11.6±3.2 mm versus radiofrequency 4.7±1.6 mm; mean±SD) and epicardial sparing (HIU 2.9±2.1 mm versus radiofrequency 0.1±0.2 mm) at all HIU powers, and increased lesion volume at HIU 20 and 30 W (P<0.0001 for all comparisons). HIU ablation over coronary arteries and surrounding epicardial fat resulted in deep lesions with normal angiographic flow. Histological disruption of coronary adventitia, but not media or intima, was noted in 44% of lesions. Conclusions-Compared with radiofrequency, HIU ablation in vivo demonstrates significantly deeper and larger lesions with greater epicardial sparing in a dose-dependent manner. Further development of this catheter may lead to a promising alternative to epicardial radiofrequency ablation.
AB - Epicardial radiofrequency catheter ablation of ventricular tachycardia remains challenging because of the presence of deep myocardial scar and adjacent cardiac structures, such as the coronary arteries, phrenic nerve, and epicardial fat that limit delivery of radiofrequency energy. High-intensity ultrasound (HIU) is an acoustic energy source able to deliver deep lesions through fat, while sparing superficial structures. We developed and tested an epicardial HIU ablation catheter in a closed chest, in vivo swine model. Methods and Results-The HIU catheter is an internally cooled, 14-French, side-facing catheter, integrated with A-mode ultrasound guidance. Swine underwent percutaneous subxyphoid epicardial access and ablation with HIU (n=10 swine) at 15, 20, and 30 W. Compared with irrigated radiofrequency lesions in control swine (n = 5), HIU demonstrated increased lesion depth (HIU 11.6±3.2 mm versus radiofrequency 4.7±1.6 mm; mean±SD) and epicardial sparing (HIU 2.9±2.1 mm versus radiofrequency 0.1±0.2 mm) at all HIU powers, and increased lesion volume at HIU 20 and 30 W (P<0.0001 for all comparisons). HIU ablation over coronary arteries and surrounding epicardial fat resulted in deep lesions with normal angiographic flow. Histological disruption of coronary adventitia, but not media or intima, was noted in 44% of lesions. Conclusions-Compared with radiofrequency, HIU ablation in vivo demonstrates significantly deeper and larger lesions with greater epicardial sparing in a dose-dependent manner. Further development of this catheter may lead to a promising alternative to epicardial radiofrequency ablation.
KW - Catheter ablation
KW - epicardium
KW - phrenic nerve
KW - swine
KW - ventricular tachycardia
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U2 - 10.1161/CIRCEP.115.003547
DO - 10.1161/CIRCEP.115.003547
M3 - Article
C2 - 26546345
AN - SCOPUS:84950148692
SN - 1941-3149
VL - 8
SP - 1491
EP - 1497
JO - Circulation: Arrhythmia and Electrophysiology
JF - Circulation: Arrhythmia and Electrophysiology
IS - 6
ER -