Distance correction for precordial electrocardiographic voltage in estimating left ventricular mass. An echocardiographic study

This study was undertaken to assess both the relation between echocardiographic measurement of left ventricular (LV) mass and commonly used electrocardiographic criteria for LV hypertrophy and the effect of the distance from the center of LV mass to the anterior chest wall on precordial voltage. Echocardiograms and standard 12 lead electrocardiograms were obtained on 100 persons, ages 3 to 79. The correlation coefficients of echocardiographically determined LV mass with ECG precordial voltage (S(v1) + R(v5) or (v6)), the Estes point score system, and a V(L) R wave voltage were .686, .721, and .531, respectively. Extrapolating from the dipole nature of the heart, the precordial voltage was multiplied by the square of the chest wall to mid LV distance to correct for the loss of energy across the distance from LV to recoding electrode. Utilizing this correlation, a much improved precordial voltage estimation of LV mass (r=.846) was obtained. The authors conclude that the distance of the center of LV mass from the chest wall influences the amplitude of recorded precordial voltage and that correction for this influence improves the correlation of precordial voltage with LV mass.