Open AccessMechanism of alternans of diastolic potential cycles during overdrive pacing of ventricular tachycardia
Author(s) -
Kaneko Yoshiaki,
Nakajima Tadashi,
Irie Tadanobu,
Kato Toshimitsu,
Iijima Takafumi,
Ota Masaki,
Tamura Mio,
Iizuka Takashi,
Kurabayashi Masahiko
Publication year - 2013
Publication title -
journal of arrhythmia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.463
H-Index - 21
eISSN - 1883-2148
pISSN - 1880-4276
DOI - 10.1016/j.joa.2012.09.003
Subject(s) - medicine , cardiology , diastole , mechanism (biology) , ventricular tachycardia , tachycardia , blood pressure , philosophy , epistemology
A 77-year-old man with a history of healed inferior myocardial infarction underwent radiofrequency catheter ablation for drugrefractory ventricular tachycardia (VT) with right bundle branch block and superior axis. VT was reproducibly induced by programmed ventricular stimulation. Pacing during VT at the basal edge of the low voltage zone, where a low-amplitude diastolic potential (DP) was recorded, showed concealed entrainment, in which the pacing stimulus-QRS was nearly equal to the DP-QRS interval, and the post-pacing interval (PPI) of the DP was equal to the tachycardia cycle length (TCL), consistent with pacing on the essential pathway of the reentrant circuit (Fig. 1). The delivery of radiofrequency energy at that site terminated and eliminated the induction of VT. Before ablation, overdrive pacing with identical output and a cycle length slightly shorter than that of the VT near the successful ablation site caused alternans of the DP to DP intervals (Fig. 2). What is the mechanism of this DP alternans?