Kawamura Mitsuharu, Kobayashi Youichi, Ito Hiroyuki, Onuki Tatsuya, Miyoshi Fumito, Matsuyama Taka-aki, Watanabe Norikazu, Ryu Shunshou, Asano Taku, Miyata Akira, Tanno Kaoru, Katagiri Takashi
Third Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan.
Circ J. 2006 Jul;70(7):926-32. doi: 10.1253/circj.70.926.
Transthoracic epicardial ablation can be an alternative to conventional treatment for critical pathways of ventricular tachycardia located in the epicardium. However, the usefulness and safety of epicardial ablation close to the coronary arteries (CA) is not clear. The purpose of the present experimental animal study was to analyze the efficacy and safety of epicardial radiofrequency (RF) ablation close to the CA.
Of the left ventricle-epicardium ablated sites, 35 lesions (20 with cooling and 15 without cooling) were close to the CA (left anterior descending artery < or = 15 mm) and 33 lesions (23 with cooling and 10 without cooling) were further from the CA. For sites close to the CA, epicardial ablation was effective in 77% (15/20) with cooling and in 40% (6/15) without cooling. There was a significant difference of effective ablation between with cooling and without cooling (p < 0.05). For cooling, epicardial lesion size could be predicted by the change of endocardial ventricular potential using a basket catheter. No damage to major epicardial arteries was detected when the catheter tip was positioned 5 mm away from the CA.
Close to the CA, RF ablation with cooling is more effective than RF without cooling and is safe if the ablation sites are located 5 mm away from the major CA.
