The Electrocardiogram in Ventricular Hypertrophy and Bundle-Branch Block

DR. KOSSMANN: Our panel has been assigned the task of unravelling for you, to the best of our ability, the dual problems of the electrocardiogram in ventricular hypertrophy and in bundle-branch block. For the achievement of this formidable assignment we have been allotted exactly 45 minutes. That we will succeed in clarifying a subject that was destined, almost from its inception a half century ago, to be characterized by repeated experimental error, fanciful speculation, and whimsical nomenclature is not likely, or more correctly, is not possible. But perhaps our deliberations will show at least that there are inadequate facts to justify making certain electrocardiographic interpretations, and drawing inevitable anatomic conclusions therefrom as is commonly practiced in the clinic. Historically the matter of bundle-branch block got off on the wrong foot, or more exactly, on the wrong side. After Eppinger and Rothberger' introduced the concept in 1910, Lewis and Rothschild2 performed experiments on dogs and defined the criteria for left and right bundle-branch block. Roughly 15 years later the classic experiments of Barker, Macleod, Alexander, and Wilson3 on an exposed human heart demonstrated that the usually meticulous Lewis, probably due to the unusual thoracic position of the dog's heart in his experiments, had mistakenly reversed the sides of the block in his conclusions. With the advent of chest leads and practical methods for recording vectoreardiograms the quest for greater refinement in the diag-