T wave alternans in idiopathic long-QT syndrome: insight from body surface mapping.
Body surface mapping was recorded during T wave alternans in two patients with idiopathic long QT syndrome. Eighty-seven lead ECGs of two consecutive beats during T wave alternans demonstrated that alternating changes in the morphology and polarity of the T wave existed mainly in the left frontal chest. The QRST isointegral maps of the same two consecutive beats showed alternation of a large negative area appearing mainly in the left frontal chest. These results indicate that T wave alternans in the two patients were related to alternate heterogeneous prolongation of the action potential duration in this region.
Shimizu
W
W
Department of Internal Medicine, National Cardiovascular Center, Osaka, Japan.
Kamakura
S
S
Arakaki
Y
Y
Kamiya
T
T
Shimomura
K
K
D000200:Action Potentials / Q000502:physiology; D018780:Body Surface Potential Mapping; D002648:Child; D002675:Child, Preschool; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008133:Long QT Syndrome / Q000175:diagnosis* / Q000503:physiopathology; D008297:Male