The Frontal Plane Vectorcardiogram in Old Inferior Myocardial Infarction

Abstract

The mid-to-late part of the frontal plane QRS loop (Frank lead system) of 150 consecutive subjects with an old inferior myocardial infarction was analyzed. During the acute episode all cases had to satisfy Myers' classical ECG criteria for the diagnosis. The vectorcardiogram was recorded months to years later. As a result of this analysis and in order to prevent overlap with values found in 450 normal control subjects, four VCG criteria are proposed for this diagnosis. The VCGs of 75 of the 150 patients fulfilled one or more of the four VCG criteria. The ECG, done at the time of VCG, satisfied Myers' or Goldberger's criteria or both criteria in 33 of these 75 patients, and an additional 24 of the 150 fulfilled either or both of these ECG criteria but had none of the four VCG criteria. Among 131 consecutively catheterized subjects who had significant disease of one or more major coronary arteries, 40 fulfilled one or more of the VCG criteria. Thirty-six of the 40 showed significant stenosis of at least the right coronary artery, and the other four, of at least the left circumflex but not of the right coronary artery. Six of these 40 fulfilled Myers' or Goldberger's criteria. Five of the 131 fulfilled either or both of these ECG criteria but none of the four VCG criteria.