OPTIMAL FREQUENCY OF RADIOFREQUENCY CATHETER ABLATION IN VITRO AND IN VIVO FOR TREATING VENTRICULAR TACHYCARDIAS : A study using various frequencies
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概要
- 論文の詳細を見る
The purpose of this study was to determine the optimal frequency for radiofrequency catheter ablation of ventricular tachycardias. A radiofrequency current was delivered from a 6F bipolar electrode catheter with a tip electrode width of 4 mm. Ablation was performed for a pulse duration of 10 sec at 20 watts (50 V and 0.4 A) at seven different frequencies between 10 and 500 kHz. We used 35 canine isolated left ventricular endocardial sites in vitro and 14 anesthetized dogs in vivo. The lesions which were ablated at frequencies of 200 and 300 kHZ were significantly larger than those at other frequencies, with a mean surface areas of 78.5 and 76,3 mm^2 and mean depths of 4.0 and 4.1 mm, respectively (p<0.05). The appearance of ventricular arrhythmias during ablation increased as the frequency decreased. One dog, to which a frequency of 100 kHZ Was applied, developed spontaneous ventricular fibrillation and died. All of the dogs which received a current with a frequency under 50 kHZ exhibited muscle cramping during ablation. Ventricular stimuli applied after ablation did not in-duce ventricular tachycardia. These results suggest that the optimal frequency for ablating a large lesion is between 200 and 300 kHz. To avoid inducing malignant ventricular arrhythmia during ablation, the frequency must exceed 200 kHz. Furthermore, a frequency below 100 kHZ Should not be used in radiofrequency catheter ablation because of the risk of arrhythmias and muscle cramping.
- 社団法人日本循環器学会の論文
- 1993-08-20
著者
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Ikeda Takanori
Kyorin University Hospital
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Ikeda Takanori
Department Of Cardiovascular Medicine Graduate School Of Medicine Kyoto University
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Yabuki So
Toho University School Of Medicine Ohashi Hospital Third Department Of Internal Medicine
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Sugi Kaoru
Division Of Cardiovascular Medicine Toho University Ohashi Medica Center
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Ninomiya Kenji
3rd Department of Internal Medicine, Ohashi Hospital, Toho University, School of Medicine
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IKEDA TAKANORI
The Third Department of Internal Medicine, Ohashi Hospital, Toho University School of Medicine
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SUGI KAORU
The Third Department of Internal Medicine, Ohashi Hospital, Toho University School of Medicine
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ENJOJI YOSHIHISA
The Third Department of Internal Medicine, Ohashi Hospital, Toho University School of Medicine
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ABE RYOJI
The Third Department of Internal Medicine, Ohashi Hospital, Toho University School of Medicine
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NINOMIYA KENJI
The Third Department of Internal Medicine, Ohashi Hospital, Toho University School of Medicine
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YABUKI SO
The Third Department of Internal Medicine, Ohashi Hospital, Toho University School of Medicine
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MAGUCHI TETSUYA
The Third Department of Internal Medicine, Toho University School of Medicine Ohashi Hospital
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Sugi Kaoru
National Sanatorium Kanagawa Hospital
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Yabuki So
Third Department Of Internal Medicine Toho University Ohashi Hospital
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Ninomiya Kenji
3rd Department Of Internal Medicine Ohashi Hospital Toho University School Of Medicine
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Suemoto Yoshinobu
Department Of Cardiology Kawaguchi Municipal Medical Center
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Yabuki Sou
1st Dept. Of Intern. Med. Toho Univ. School Of Med.
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Yabuki So
Third Department Of Internal Medicine
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Yabuki Sou
Third Department Of Internal Medicine Toho University Ohashi Hospital
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Ninimiya Kenji
Third Department Of Internal Medicine Toho University Ohashi Hospital
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Yabuki So
3rd Division Department Of Internal Medicine Toho University Ohashi Hospital
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Enjoji Yoshihisa
Division Of Electrophysiological Lab. Cardiovascular Center Kyoto Katsura Hospital
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Abe Ryoji
3rd Department Of Internal Medicine Ohashi Hospital Toho University School Of Medicine
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Maguchi Tetsuya
The Third Department Of Internal Medicine Toho University School Of Medicine Ohashi Hospital
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Saito Yoshinori
Third Department Of Internal Medicine
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Yabuki So
The Third Dept. Of Int. Med. Toho Univ. School Of Med. .
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Sato Yuichi
Dept. Of Cardiol. Cedars-sinai Med. Ctr.
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