Kaoru Okishige1, Ken Okumura2, Takuo Tsurugi2, Akihiko Yotsukura3, Tadafumi Nanbu3, Hirotaka Sugiura4, Akiko Sanada4, Yusuke Kondo5, Masahiro Takano5, Takehiko Keida6, Masaki Fujita6, Hiroki Kamiya7, Kunihiko Tsuchiya7, Kazumasa Adachi8, Yukinori Katoh8, Kenichi Hiroshima9, Kei Yamamoto9, Keiichi Ashikaga10, Tadashi Hoshiyama10, Tetsuo Sasano11, Kenzo Hirao11. 1. Heart Center, Japan Red Cross Yokohama City Bay Hospital, Yokohama, Japan. okishige@yo.rim.or.jp. 2. Cardiovascular Department, Saiseikai Kumamoto Hospital, Kumamoto, Japan. 3. Cardiovascular Department, Hokko Memorial Hospital, Sapporo, Japan. 4. Cardiovascular Department, Niigata Medical Center, Niigata, Japan. 5. Department of Advanced Cardiovascular Therapeutics, Chiba University Graduate School of Medicine, Chiba, Japan. 6. Cardiology Department, Edogawa Hospital, Tokyo, Japan. 7. Cardiovascular Department, Gifu Heart Center, Gifu, Japan. 8. Cardiovascular Department, Akashi Medical Center, Akashi, Japan. 9. Cardiovascular Department, Kokura Memorial Hospital, Kokura, Japan. 10. Cardiovascular Department, Miyazaki Medical Association Hospital, Miyazaki, Japan. 11. Arrhythmia Center, Tokyo Medical and Dental University, Tokyo, Japan.
Abstract
PURPOSE: Cryoenergy has been demonstrated to be a safe alternative to radiofrequency ablation for catheter ablation of atrioventricular nodal reentrant tachycardia (AVNRT). This study aimed to evaluate the safety and efficacy of cryoablation in patients with AVNRT. METHODS: A multicenter retrospective study was performed. Two hundred eighty-three consecutive patients with AVNRT underwent cryoablation. Cryomapping at - 30 °C and - 80 °C was performed to predict cryoablation outcome and ascertain antegrade conduction. Cryoenergy was delivered subsequently at the same spot (cryoablation at - 80 °C) for 240 s. RESULTS: Ablation procedure was acutely successful in 281 out of 283 patients (99.3%). Of note, 22 patients (10.1%) had transient AV block during the cryoablation, but no injurious effects on AV conduction were provoked during cryomapping. During a follow-up period of 367 ± 35 days, the recurrence rate was 3.9% (11 out of 281). There were no significant differences among the patients with a complete elimination of slow pathway conduction, AH jump without an echo beat, and AH jump with a single echo beat, in terms of the long-term recurrence of AVNRT. CONCLUSIONS: Cryoablation of AVNRT appears to be effective both acutely and during the long-term with a minimal risk of unwanted injuries to the conduction system. It seems to be important to monitor the antegrade conduction during cryoenergy applications, even when cryomapping demonstrates a safe location for cryoablation. The recurrence rate of AVNRT did not differ according to the properties of the residual slow pathway conduction.
PURPOSE: Cryoenergy has been demonstrated to be a safe alternative to radiofrequency ablation for catheter ablation of atrioventricular nodal reentrant tachycardia (AVNRT). This study aimed to evaluate the safety and efficacy of cryoablation in patients with AVNRT. METHODS: A multicenter retrospective study was performed. Two hundred eighty-three consecutive patients with AVNRT underwent cryoablation. Cryomapping at - 30 °C and - 80 °C was performed to predict cryoablation outcome and ascertain antegrade conduction. Cryoenergy was delivered subsequently at the same spot (cryoablation at - 80 °C) for 240 s. RESULTS: Ablation procedure was acutely successful in 281 out of 283 patients (99.3%). Of note, 22 patients (10.1%) had transient AV block during the cryoablation, but no injurious effects on AV conduction were provoked during cryomapping. During a follow-up period of 367 ± 35 days, the recurrence rate was 3.9% (11 out of 281). There were no significant differences among the patients with a complete elimination of slow pathway conduction, AH jump without an echo beat, and AH jump with a single echo beat, in terms of the long-term recurrence of AVNRT. CONCLUSIONS: Cryoablation of AVNRT appears to be effective both acutely and during the long-term with a minimal risk of unwanted injuries to the conduction system. It seems to be important to monitor the antegrade conduction during cryoenergy applications, even when cryomapping demonstrates a safe location for cryoablation. The recurrence rate of AVNRT did not differ according to the properties of the residual slow pathway conduction.