Relation between the location of the infarcted area in body surface isopotential mapping and the location of myocardial infarction in vectorcardiography.
In order to examine whether our method of determining the location of the infarcted area in body surface isopotential mapping (MAP) is adequate for clinical use, a comparison was made between the location of the infarcted area using MAP and the location of myocardial infarction using vectorcardiography (VCG). The percentage of agreement between MAP and VCG in the retrospective study was 91.7% in the anterior wall, 76.7% in the lateral wall, 93.3% in the inferior wall and 73.3% in the posterior wall. The reason for the disagreement between these two methods was investigated, and criteria for determining the infarcted area using MAP and vectorcardiographic criteria for myocardial infarction were partly corrected in anterior, lateral and (high) posterior infarction to increase the clinical accuracy of both methods. Consequently, the percentage of agreement in the four walls ranged from 83.7% to 87.9%, and the diagnostic value of MAP for the infarcted area was not inferior but was more sensitive than that of VCG except in anterior infarction. In the prospective study, the same result was obtained. Secondly, in order to establish the superiority of MAP or VCG, the sensitivity and specificity of MAP and VCG to SCG (thallium-201) were calculated. Except in the anterior wall, the sensitivity of MAP to SCG was higher than that of VCG to SCG, especially in the lateral and posterior walls. Accordingly, it is suggested that MAP is the method of choice in determining the infarcted area in clinical cases.