Electrical space-time abnormalities of ventricular depolarization in patients with Brugada syndrome and patients with complete right-bundle branch blocks studied by magnetocardiography.
BACKGROUND
Both ventricular depolarization abnormalities (QRS complex) and repolarization ones (ST/T) are still controversial in literature. The objective of this study was to clarify the space-time variations that occur in patients carriers of Brugada syndrome using Magnetocardiography and also compare them with cases of complete right-bundle branch block (CRBBB) and individuals without any dromotropic disorder (control group).


RESULTS
Magnetocardiograms (MCGs) of Brugada syndrome patients (n = 16), CRBBB patients (n = 14), and members of a control group (n = 46) at rest were recorded. The MCGs were used to produce a whole-heart electrical-activation diagram (W-HEAD), which can visualize the spatial time-variant activation in the whole heart. In the W-HEAD pattern, three activations were located in the left ventricle, and CRBBB patients had a wide peak with about 65-ms delay on the right anterior side. While the Brugada syndrome pattern has a posteromedian left-ventricle excitation, that is half the amplitude that occurs in CRBBB patients, the electrical conduction rate to the posterosuperior septum area was low.


CONCLUSIONS
The W-HEAD data made it possible to visualize space-time depolarization abnormalities. These findings suggest that the electrical conduction rate to the posterosuperior septum area in Brugada syndrome cases is low, and this low activation may be a feature of typical Brugada syndrome.
Kandori
Akihiko
A
Central Research Laboratory, Hitachi, Ltd., Kokubunji, Tokyo, 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
D000328:Adult; D002037:Bundle-Branch Block / Q000175:diagnosis / Q000503:physiopathology*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008280:Magnetics; D008297:Male; D008875:Middle Aged; D013577:Syndrome