Left Axis Deviation

Abstract

Our understanding of the meaning of the electrocardiogram is greatly furthered by careful comparison of cardiac hypertrophy and cardiac damage observed post mortem with electrocardiograms taken during the last weeks of life. An electrocardiographic-pathologic correlation of 672 cases is reported in which the roles of left ventricular hypertrophy, myocardial infarction, and other factorsin the production of left axis deviation are examined. A heretofore unrecognized QRS-complex syndrome of infarction is described in which the QRS forces are diagnostically abnormal but no "Q waves" are seen in the conventional leads. The roles of hypertrophy, variations in body build, chronic pulmonary disease, and various types of "parietal block" in the production of left axis deviation are studied.