Onset of Reentrant Ventricular Tachycardia Modulated by Variable Impulse Propagation through the Zone of Slow Conduction

Yoshiaki Kaneko, Tadashi Nakajima, Tadanobu Irie, Akihiro Saito, Masaki Ota, Toshimitsu Kato, Takafumi Iijima, Mio Tamura, Hiroaki Kobayashi, Masahiko Kurabayashi
2011 Internal medicine (Tokyo. 1992)  
We report an 18-year-old woman, who had undergone surgical repair of tetralogy of Fallot, and then underwent successful intracardiac recordings within the zone of slow conduction (ZSC) of the reentry circuit on the initiation of premature ventricular contractions (PVC) and reentrant ventricular tachycardia (VT), obtained with multielectrode basket catheter. PVC a) were caused by wavefronts of sinus cycles entering and exiting the ZSC, and b) were not repetitive because the wavefront of the PVC
more » ... vefront of the PVC could not reenter the ZSC. Similarly, VT developed after delayed potentials of sinus cycles, and was sustained because the wavefront following the 1st cycle of VT was able to repetitively reenter and exit the ZSC. Thus, spontaneous changes in the conductivity of the ZSC, like an on-off switch, appeared to determine the onset and sustenance of reentrant VT. An 18-year-old woman, who had undergone surgical repair of tetralogy of Fallot at 2 years of age, was referred to our hospital for catheter ablation of sustained VT. The surgical technique included patch closure for ventricular septal defect (type III), infundibular resection and H-shaped valvotomy for pulmonary stenosis, following a transverse resection of the right ventricular outflow tract. The 12-lead ECG during sinus rhythm showed first-degree AV block and
doi:10.2169/internalmedicine.50.4230 pmid:21245634 fatcat:3vcyoedzyjgdll5etwdoikp2wm