[Detection of wall motion abnormality in old myocardial infarction with principal component analysis to body surface potential distribution].

The purpose of this study was to examine the correlation between body surface potential distribution and the extent of abnormally contracting segments (ACS) of the left ventricle in patients with old myocardial infarction (MI). Body surface potential distribution was quantitatively analyzed using principal component analysis. The first 6 principal components were extracted from data set obtained from both 25 normal subjects and 100 patients. The z scores were calculated at every 4 or 8 msec in another 81 patients with previous MI. In conclusion, the principal component analysis on body surface maps successfully condensed mapped data without significant loss of total variance and minute differences in the extent of ACS were sensitively detected on z scores of principal components.