Magnetocardiography study on ventricular depolarization-current pattern in patients with brugada syndrome and complete right-bundle branch blocks.
BACKGROUND
The objective of this study is to use magnetocardiography to determine the existence of a small abnormal current during ventricular depolarization in patients with Brugada syndrome. To understand this small difference in abnormal current during ventricular depolarization, we compared abnormal currents of patients with cases of complete right-bundle-branch block (CRBBB).


RESULTS
We developed a whole-heart electrical bull's eye map (WHEBEM) that uses magnetocardiograms (MCGs) to visualize the current distribution in a circular map. MCGs of Brugada syndrome patients (n = 16), CRBBB patients (n = 10), and controls (n = 12) at rest were recorded. In the WHEBEMs of Brugada syndrome patients, the magnitude of the S-wave current in the upper-right direction of the anterior side is larger than that of the controls. In addition, the R-wave current direction is similar to that of the controls, and the R-wave vector is distributed over a larger area than that of the controls. On the other hand, the CRBBB patients have a distribution of R-wave currents over a larger area in the left anteromedian region and the left posteromedian region. Moreover, in all CRBBB patients, S-wave currents with a large magnitude have the same direction distributed over a small area.


CONCLUSIONS
The WHEBEM findings suggest that there is an abnormal current in the direction to the upper right (in the S-wave) in the anterosuperior region of Brugada syndrome patients. We thus conclude that a WHEBEM has the potential to detect characteristics of heart disease.
Kandori
Akihiko
A
Advanced Research Laboratory, Hitachi, Ltd., Kokubunji, Tokyo 185-8601, Japan. kandori@rd.hitachi.co.jp
Miyashita
Tsuyoshi
T
Ogata
Kuniomi
K
Shimizu
Wataru
W
Yokokawa
Miki
M
Kamakura
Shiro
S
Miyatake
Kunio
K
Tsukada
Keiji
K
Yamada
Satsuki
S
Watanabe
Shigeyuki
S
Yamaguchi
Iwao
I
D000293:Adolescent; D000328:Adult; D018780:Body Surface Potential Mapping / Q000379:methods*; D053840:Brugada Syndrome / Q000503:physiopathology*; D002037:Bundle-Branch Block / Q000503:physiopathology*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D053798:Magnetocardiography / Q000379:methods*; D008297:Male; D008875:Middle Aged; D014584:User-Computer Interface