[The utility of body surface isochrone mapping of recovery time in diagnosing effort angina].
Myocardial ischemia is characterized by ST depression on a standard electrocardiogram caused by shortening of the action potential duration (APD). We investigated whether shortening of the APD can be used as a screening criterion, in place of ST depression, to diagnose effort angina. Estimation of APD was made based on recovery time (RT) on a 16-lead system signal-averaged electrocardiogram (SAE). RT was defined as the interval between the onset of the QRS complex and the maximum positive value during the T wave of SAE. The values of RT measured at each lead were plotted on a graph to produce an electrocardiographic isochrone map. RT were significantly shortened in all electrocardiographic leads in patients with effort angina. Shortening in RT was especially marked in the right precordal leads and was shown to be a highly specific criterion for screening effort angina.
Sasaki
R
R
First department of internal medicine, Hyogo College of Medicine.
Tani
H
H
Sugisawa
K
K
Iwasaki
T
T
D000368:Aged; D000787:Angina Pectoris / Q000175:diagnosis*; D018780:Body Surface Potential Mapping / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity