Purpose: In
this study, we examined the hypothesis that the preferential conduction
property along left lateral ridge (LLR) might affect the arrhythmogenicity of
left pulmonary veins (LPVs).
Methods: The study population included 40 consecutive AF patients.
Radiofrequency energy (RF) was
sequentially delivered along the LLR from a lower to upper manner during postero-lateral CS pacing
during an isoproterenol infusion.
Results: The
conduction time during pacing from the CS was
significantly prolonged during radiofrequency (RF) deliveries (before vs. after, upper; 91±26ms vs. 127±38ms,
p<0.001, lower; 86±21ms vs. 103±22ms, p<0.001). Remarkable prolongation
of more than 30ms was observed in 19 of 40 patients (48%) (both LPVs, 6; only
the upper LPVs, 12; and only the lower LPV, 1). Sites with a remarkable
prolongation were observed at the carina between the LPVs (4), anterior site of
the upper LPV carina (10), anterior wall of the lower LPV (3), and bottom of
the lower LPVs (2). Thirty-three arrhythmogenic foci (AMF) from the LPVs were
observed in 23/40 patients (56%). The
conduction time during pacing
from the LPVs during the
RF delivery was significantly longer in the patients with AMF from the upper
LPV than in those patients without (107±36ms vs. 146±40ms, p<0.01).
Conclusion: The LLR includes the
preferential conduction properties between the CS and LPVs, and the observation
of the serial changes during the RF delivery could provide us information about
the LPVs arrhythmogenicity.
Credits: Toshiya Kurotobi, MD PhD; Yoshihisa Shimada, MD PhD; Naoto Kino, MD; Kazato Ito, MD; Kosuke Takehara, MD; Daisuke Tonomura, MD; Tomohiro Nakashoji MD; Kentaro Yano, MD; Chiharu Tanaka, MD; Masataka Yoshida, MD. PhD; Takao Tsuchida, MD PhD; Hitoshi Fukumoto, MD PhD