Usefulness of the pediatric electrocardiogram in detecting left ventricular hypertrophy: results from the Prospective Pediatric Pulmonary and Cardiovascular Complications of Vertically Transmitted HIV Infection (P2C2 HIV) multicenter study

Abstract

Background: A shortcoming of the pediatric electrocardiogram (ECG) appears to be its inability to accurately detect left ventricular hypertrophy (LVH). This study prospectively assesses the usefulness of the pediatric ECG as a screening modality for LVH.

Methods: Concomitant echocardiograms and ECGs from a large cohort of children who were exposed to the human immunodeficiency virus (HIV; uninfected) and children who were infected with HIV were compared. By use of the values of Davignon et al, qualitative determination of LVH and quantitative criteria for LVH (RV6, SV1, RV6+SV1, QV6, and Q(III) >98% for age, R/SV1 <98% for age, and [-]TV6) were compared to body surface area adjusted for left ventricular (LV) mass z score. Results were then stratified according to weight and weight-for-height z scores. New age-adjusted predicted values were then constructed from children of a mixed race who were HIV-uninfected, < or =6 years old, and similarly assessed.

Results: The sensitivity rate was <20% for detecting increased LV mass, irrespective of HIV status; the specificity rate was 88% to 92%. The sensitivity rate of the individual criteria ranged from 0 to 35%; the specificity rate was 76% to 99%. Test sensitivities remained low when stratified by weight and weight-for-height z scores. Areas under the receiver operator characteristic curves were between 0.59 and 0.70, also suggesting poor accuracy of the ECG criteria. By use of new age-adjusted predicted values, the sensitivity rate decreased to <17%, and the specificity rate increased to 94% to 100%.

Conclusion: The ECG is a poor screening tool for identifying LVH in children. Sensitivity is not improved with revision of current criteria.

Figure 1

Longitudinal changes in mean R amplitude in lead V₆ (A) and mean S amplitude in lead V₁ (B) according to HIV group and age. The vertical bars indicate the 95% CIs for the mean. A and B, RV₆ and SV₁, respectively, in mV for the neonatal cohort (n = 77 HIV-infected, group IIa; and n = 251 HIV-uninfected, group IIb) and for the older cohort (n = 106, group I). Scatterplots and rates of change for LV mass z scores versus RV₆ (C) and LV mass z scores versus SV₁ (D) for the older HIV-infected cohort (n = 148 and 147 children, respectively). Solid dots indicate LVH on ECG and open circles indicate no LVH on ECG.

Figure 2

Receiver operator characteristics curves for each LVH amplitude criterion. An receiver operator characteristic curve is a plot of the true-positive proportion (sensitivity) against the false-positive proportion (1−specificity) for various possible values for each ECG criterion. None of the ECG criteria provided strong discrimination of LVH on the basis of the echocardiogram LV mass z score.

Figure 3

Scatterplots, rates of change versus age, and 95% prediction intervals for each of the 7 ECG criteria for LVH. The linear regression and 95% prediction intervals were calculated by using 250 children who were HIV-uninfected without increased LV mass and who were observed from birth. The dashed lines identify the 98th or 2nd percentiles from Davignon et al. The regression equations are available from the authors at keasle2@sph.emory.edu.