Experimental study of myocardial infarction through the use of body surface isopotential maps: ligation of the anterior descending branch of the left coronary artery.

This investigation was undertaken to diagnose the location and extent of myocardial infarction with the use of maps which give significant information about the ventricular activation process. Myocardial infarction was experimentally caused by ligation of the anterior descending branch of the left coronary artery. All classes were classified into three groups (A,B, and C) according to the location and extent of infarction. The map of each group had its own characteristics, as follows. In Group A no pisitive potentials appeared on the left anterior chest surface all through ventricular depolarization. In Group B, like Group A, the negative area occupied the whole left anterior chest surface in the early stage. But in the later stages there appeared a positive area on the left anterior surface. As to Group C, there was no abnormality in its early stage, but in its middle stage, the negative area was found on the left anterior chest surface. Thus the sequential maps can be helpful in diagnosing the location and extent of myocardial infarction, and will be applied to clinical use much more.