Electrocardiographic diagnosis of left ventricular hypertrophy: is the method obsolete or should the hypothesis be reconsidered?

The current ECG diagnosis of LVH is based on QRS voltage criteria and aims to estimate left ventricular mass. Its underlying hypothesis includes unsta ted assumptions about the non-spatial determinants of QRS voltage; that the electrical properties of hypertrophied myocardium do not differ from those healthy myocardium, and that they are not changed in the course of develop ing LVH. Since these two assumptions are not true, the performance of the v oltage criteria is limited and is reflected in the high number of so-called false negative ECG results, as well as their low sensitivity. The reconsid ered hypothesis is based on a more complex understanding of LVH and on the analysis of information provided by electrocardiography. It considers false negative results for LVH diagnosis as a relative voltage deficit, and intr oduces a new parameter for its quantification: the specific potential (the relative QRS voltage). The relative voltage deficit is related to changes o f active and passive electrical properties (electrophysiological remodellin g) of the hypertrophied myocardium. This new hypothesis also takes Into acc ount changes of the relative QRS voltage in different stages of LVH. The po tential of this concept is its usefulness as a parameter in the frame of di agnostics of LVH, of diffuse changes of myocardium, in cardiovascular risk assessment, and well as for evaluation of the effects of therapy. (C) 2001 Harcourt Publishers Ltd.