T loop in posterior myocardial infarction: a useful clue to vectorcardiographic diagnosis.
In order to differentiate posterior (posterolateral) myocardial infarction (PMI) from the anterior shift of the QRS loop in "normal variant" cases using a vectorcardiogram, the T loop as well as the QRS loop in the transverse plane (TP) were analyzed in 34 elderly Japanese males with angiographically-proven PMI and in 197 elderly Japanese males with normal coronary arteries and ventricles. T loops in the TP were longer, narrower and more anterior in PMI cases. After this analysis, we propose new criteria for PMI: (A and B) A: maximal T vector equal or anterior to 60 degrees in TP B: at least two of the following three: maximal QRS voltage/maximal T voltage in TP equal to or less than 3.0; QRS-T angle equal to or less than 75 degrees in TP; width/length of T equal to or less than 0.15 in TP. These new criteria for PMI are more specific (p less than 0.01) and more sensitive (p less than 0.05) than Hoffman's criteria.
Takatsu
F
F
Osugi
J
J
Nagaya
T
T
Uwatoko
M
M
Watabe
S
S
Ishikawa
H
H
D000328:Adult; D017023:Coronary Angiography; D004562:Electrocardiography / Q000379:methods; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000503:physiopathology; D014672:Vectorcardiography / Q000379:methods*