Age and sex dependent criteria for lower limits of QRS voltages

The aim of this study was to examine whether criteria for low QRS voltage should be age and sex dependent. A database of 1496 normal ECGs from healthy adults was analysed using the University of Glasgow ECG analysis program. Correlation coefficients between peak- to-peak QRS voltages (ppQRS) and age were obtained. Differences in ppQRS due to sex were measured statistically. New thresholds were picked from the observations made and were tested on a second study population. The lower limits of ppQRS for males were significantly higher than for females in leads VI to V6 (p = 0.031, exact binomial test). Lowering the threshold for abnormality in these leads to 0.8mV for females resulted in an increase in specificity from 99.7% to 99.9%. There was evidence of correlation with age in males. In particular, the evidence supported using a different threshold for males under 40.