IS THE ECHOCARDIOGRAM AN APPROPRIATE ECG VALIDITY STANDARD FOR THE DETECTION AND CHANGE IN LEFT-VENTRICULAR SIZE

The echocardiogram (Echo) is the validity standard for left ventricula r mass (LVM) and LV hypertrophy (LVH). Numerous studies have confirmed modest correlations between the electrocardiogram (EGG) and Echo for LVM and low ECG sensitivity for Echo-LVH. In spite of this, investigat ors continue modeling ECG parameters to optimize their relation with t he Echo. The authors studied the association between eight ECG criteri a and Echo-LVM estimates in a biracial population of men and women wit h mild hypertension. The Echo-LVM was determined by the Penn conventio n and expressed in grams, g/m, g/m(2), and g/m(2.7). The ECGs and Echo s were recorded at baseline, 3 months, and annually for 4 years. The E CGs were computer processed to define the following criteria: (1) Casa le/Devereux, (2) Cornell product, (3) Cornell voltage, (4) 12-lead vol tage product, (5) sum of the 12-lead, (6) Rautaharju, (7) Sokolow-Lyon and (8) Romhilt-Estes point score. The major findings were: (1) corre lations between the ECG and Echo were modest for level and minimal for change, (2) Echo indexing did not alter correlations with ECG criteri a, (3) white men and women show higher correlations for level and chan ge than blacks, (4) repeatability of the Echo-LVM index was 0.7, makin g it a ''moving'' validity standard for the EGG, (5) further ECG model ing to predict Echo-LVH, especially in whites, is not a productive app roach, and (6) ECG measurements should be combined with other non-ECG characteristics when detecting LVH, and future ECG-LVM studies should investigate the prognostic value of ECG characteristics and use diseas e outcome as the validity standard.