Preferential Conduction Across the Ventricular Outflow Septum in Ventricular Arrhythmias Originating From the Aortic Sinus Cusp
Takumi Yamada, MD*,*,
Yoshimasa Murakami, MD
,
Naoki Yoshida, MD
,
Taro Okada, MD
,
Takeshi Shimizu, MD
,
Junji Toyama, MD
,
Yukihiko Yoshida, MD
,
Naoya Tsuboi, MD
,
Masahiro Muto, MD
,
Yasuya Inden, MD
,
Makoto Hirai, MD
,
Toyoaki Murohara, MD
,
Hugh T. McElderry, MD*,
Andrew E. Epstein, MD*,
Vance J. Plumb, MD* and
G. Neal Kay, MD*
* Division of Cardiovascular Diseases, University of Alabama at Birmingham, Birmingham, Alabama
Division of Cardiology, Aichi Prefectural Cardiovascular and Respiratory Center, Ichinomiya, Japan
Division of Cardiology, Nagoya Dai-ni Red Cross Hospital, Cardiovascular Center, Nagoya, Japan
Department of Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan.

View larger version (53K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 1 Activation Map of the RVOT and the Cardiac Tracings During PVCs (Case 8)
Activation mapping of the premature ventricular contractions (PVCs) was performed in a limited area of interest on the remap, which was made by extracting the anatomical frame out of the baseline map during sinus rhythm. The earliest ventricular activation (EVA) indicated by the red area was observed in a fairly wide area on the posterior septum of the right ventricular outflow tract (RVOT) during the PVCs. The EVA relative to the onset of the QRS was 0 ms, and the unipolar electrogram at the EVA site showed a small initial r wave on the shoulder. A few radiofrequency applications targeting the EVA site in the RVOT could not eliminate the PVCs. ABLd/p = the distal/proximal electrode pair of the ablation catheter in the RVOT; ABLuni = the distal unipolar electrode of the ablation catheter in the RVOT; PA = posteroanterior.
|
|

View larger version (18K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 2 Pace Mapping (Case 8)
The PVCs with a left coronary sinus cusp (LCC) origin showed a left bundle branch block and inferior QRS axis morphology with a QRS transition between V4 and V5. An excellent pace map was obtained at the EVA site in the RVOT (pace map [PM] score = 22/24). However, a poor PM was obtained at the EVA site in the LCC (PM score = 5/24). The pacing stimulus to QRS interval was 0 ms and 50 ms during pace mapping from the RVOT and LCC, respectively. Abbreviations as in Figure 1.
|
|

View larger version (63K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 3 Activation Map of the RVOT and LCC During PVCs (Case 8)
The EVA was observed in the LCC (white arrows), and a single RF application there could successfully eliminate the PVCs. The distance between the EVA in the RVOT and successful ablation site in the LCC was 9.7 mm. RL = right lateral; other abbreviations as in Figure 1.
|
|

View larger version (60K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 4 The Successful Ablation Site in the LCC (Case 8)
The local ventricular activation preceded the onset of the QRS by 24 ms, and the unipolar electrogram showed a QS pattern at the successful ablation site. The pink line indicates the coronary angiographic catheter deployed in the left coronary artery (LCA). ABL = the ablation catheter in the left coronary sinus cusp; LAO = left anterior oblique; RAO = right anterior oblique; RVA = right ventricular apex; RVOTd/p = the distal/proximal electrode pairs of the right ventricular outflow tract catheter; other abbreviations as in Figures 1 and 2.
|
|

View larger version (29K):
[in this window]
[in a new window]
[Download PPT slide]
|
Figure 5 Schema of the Ventricular Arrhythmia Origin, Breakout Site, and Preferential Conduction From the LCC Origin to the RVOT or Left Ventricular Septum
(A) A schema corresponding to the group 2 cases. (B) A schema corresponding to the group 1 cases. (C) A schema corresponding to the group 3 cases. LAD = left anterior descending coronary artery; LCX = left circumflex coronary artery; NCC = noncoronary sinus cusp; RCC = right coronary sinus cusp; other abbreviations as in Figures 1 and 2.
|
|
Copyright © 2007 by the American College of Cardiology Foundation.