Sato Hirokazu, Yagi Tetsuo, Namekawa Akio, Ishida Akihiko, Yamashina Yoshihiro, Nakagawa Takashi, Sakuramoto Manjirou, Sato Eiji, Yambe Tomoyuki
Division of Cardiology, Sendai City Hospital, Wakabayashi-ku, Shimizukouji3-1, Sendai, Japan.
J Interv Card Electrophysiol. 2012 Mar;33(2):127-33. doi: 10.1007/s10840-011-9622-9. Epub 2011 Oct 13.
Limited information is available about focal atrial tachycardia (AT) arising from cavotricuspid isthmus (CTI).
The purpose of this study is to evaluate the electrocardiographic and electrophysiologic characteristics of a focal AT arising from the CTI.
From a consecutive series of 92 patients undergoing radiofrequency catheter ablation (RFCA) for focal AT, three (4.4%) patients (three men) with a focal AT arising from the CTI were studied.
The median age was 71 years (range, 50 to 81 years). None of the patients had a history of CTI-dependent atrial flutter. The electrocardiogram (ECG) of a focal AT showed a significant negative F-wave in the inferior leads. Focal AT could be reproducibly initiated and terminated with programmed stimulation. The focus of the tachycardia was localized to the central isthmus in two and the paraseptal isthmus in one patient. The median tachycardia cycle length was 275 ms (range, 260 to 310 ms). In two patients, the focal AT was adenosine insensitive. In all of the patients, tachycardia was entrained from multiple right atrial sites, including the earliest activation site. RFCA was acutely successful in all patients. Long-term success was achieved in all patients over the median follow-up of 18 months (range, 6 to 33 months).
Cavotricuspid isthmus is an uncommon site of origin for focal AT. This focal AT has unique electrocardiographic characteristics such as saw-tooth morphology on ECG and is suggested to be caused by a focal reentrant circuit located at the CTI. Long-term success is achieved with focal ablation.
关于源自腔静脉三尖瓣峡部（CTI）的局灶性房性心动过速（AT）的信息有限。
本研究旨在评估源自CTI的局灶性AT的心电图和电生理特征。
在连续92例行射频导管消融（RFCA）治疗局灶性AT的患者中，研究了3例（4.4%）源自CTI的局灶性AT患者（3名男性）。
中位年龄为71岁（范围50至81岁）。所有患者均无CTI依赖性房扑病史。局灶性AT的心电图（ECG）在下壁导联显示明显的负向F波。局灶性AT可通过程序刺激反复诱发和终止。心动过速的起源部位在2例患者中位于中央峡部，1例患者位于间隔旁峡部。中位心动过速周期长度为275毫秒（范围260至310毫秒）。2例患者的局灶性AT对腺苷不敏感。在所有患者中，心动过速可从多个右心房部位（包括最早激动部位）被拖带。所有患者射频消融即刻成功。在中位随访18个月（范围6至33个月）期间，所有患者均获得长期成功。
腔静脉三尖瓣峡部是局灶性AT少见的起源部位。这种局灶性AT具有独特的心电图特征，如心电图上的锯齿样形态，提示由位于CTI的局灶性折返环引起。局灶性消融可获得长期成功。
