The Laboratory has made important contributions toward improved electrocardiographic detection and quantification of left ventricular hypertrophy. Following earlier work to establish improved voltage criteria, we have developed more sensitive criteria based on the product of QRS duration and voltage, as an approximation of the area under the QRS complex, without any loss in specificity. As an extension of this approach, algorithms for derivation of time-voltage areas from the standard ECG have been developed for additional improvement in test sensitivity and for simple estimation of ventricular mass. Additional work focuses on gender differences in criteria for hypertrophy and on application of these newly developed criteria to multicenter population studies for both identification of hypertrophy and for risk stratification in patients with Hypertension. The laboratory is also involved in the development and testing of new ECG measures of repolarization abnormality, based on both simple QT dispersion measurements as well as more complex analyses of the T-wave vector using principal component analysis, for risk stratification.