Analysis of bites on three-dimensional vectorcardiography after coronary artery ligation in dogs.
The serial changes in the QRS loops of vectorcardiograms were investigated following ligation of a branch of the left anterior descending artery (LAD) by the three-dimensional rotation method in 18 dogs. Concave inflections of the QRS loop, defined as "bites," were best delineated when the loop was viewed from a left cranial or right caudal direction. Bites appeared 48 +/- 8 minutes after LAD ligation in all of the dogs, and their development was closely related to the temporal changes in the % sigma R and QRS point score on a standard 12-lead electrocardiogram. Q waves were not observed on the electrocardiograms in 9 dogs. In the remaining 9, they appeared 117 +/- 18 minutes after LAD ligation. The bite duration, area, and amplitude were compared with the anatomical extent of the infarcts. A significant positive correlation was found between bite duration and infarct size. The detection of bites on the three-dimensionally rotated vectorcardiogram appears to have a high sensitivity for anterior myocardial infarction and could potentially become a useful diagnostic tool.
Morikawa
J
J
Third Department of Internal Medicine, Kyoto Prefectural University of Medicine, Japan.
Furukawa
T
T
Tanaka
H
H
Tsujimura
Y
Y
Bamba
M
M
Kitamura
K
K
Habuchi
Y
Y
D000818:Animals; D003331:Coronary Vessels; D004285:Dogs; D004562:Electrocardiography; D008026:Ligation; D008433:Mathematics; D009203:Myocardial Infarction / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology*; D014672:Vectorcardiography / Q000379:methods