Electrocardiographic characteristics, anthropometric features, and cardiovascular risk factors in a large cohort of adolescents

Abstract

AimsThe characteristics of electrocardiographic (ECG) patterns in the general population of adolescents are insufficiently defined. The purpose of this study is to report ECG patterns and their association with anthropometric characteristics.Methods and resultsTwenty-four thousand and sixty-two students of Roman schools, aged 12–19, were screened with ECG and physical examinations. Electrocardiographic abnormalities were classified as either minor/non-clinically relevant or major, and anthropometric measures were evaluated per age class. Obesity prevalence was 20.9%, with a higher rate in younger students (P < 0.008 for all comparisons, except for the pair 16–17 vs. 18–19 years). Stage 1 hypertension was found in 3.14% of adolescents, Stage 2 hypertension in 0.45% of adolescents, and isolated systolic hypertension in 11.7% of adolescents. Heart rate and QT interval corrected for heart rate (QTc) decreased with increasing age. The QTc was longer in females than in males over 14 years. A higher rate of incomplete right bundle branch block (RBBB) was observed in underweight students (21.58% vs. 15.10% in non-underweight students, P < 0.0001). Complete RBBB was the most common major ECG abnormality (1.6%). It was associated with height irrespective of age, sex, and body mass index (odds ratio 17.9; 95% confidence interval 5.0–64.6) and more frequent in students regularly practicing physical activity (1.80% vs. 1.02%, P = 0.0009).ConclusionHeart rate and QTc decreased with increasing age. The QTc was longer in females than in males over 14 years. RBBB was the most common major abnormality and was associated with higher stature. The prevalence of some cardiovascular risk factors in adolescents is provided.

Age-Related Electrocardiographic Characteristics of Male Junior Soccer Athletes

“…The distribution of HR, P-wave duration, PR interval, QRS duration, and QT and QTc intervals per 2-year age classes and quartiles are shown in Supplementary Figure 1. We divided it into 2year classes to be consistent with the previously published studies related to normal ECG systematic values in pediatric patients (7).…”

“…The mean HR slowed with increasing age, as in our population, however, HR ranged from 83.6 bpm for 12-13 years to 74.3 bpm for 18-19 years, while in our population of trained athletes, the same age classes manifested a significantly lower HR value (68 bpm for 12-13 years and 59 bpm for 17-18 years), suggesting the significant impact of intense training. Similarly, the PR interval was also increased (133 ms for 12-13-year-old high-school adolescents vs. 136 ms in 12-13-year-old athletes, reaching 143 ms at 18 years of age) as was the QRS duration (85 ms for 12-to 13-year adolescents vs. 90 ms for athletes, reaching 98 ms at 18 years of age), while the QT was inversely related, probably due to HR reduction (7). Only 67% of the study population of high-school students reported exercising regularly and this percentage declined at higher classes of age, dropping to 57% at 18 years, so almost a third of the student population was composed of sedentary adolescents.…”

“…The current literature has mainly focused on the prevalence and evolution of uncommon and training-unrelated ECG findings, such as T-wave inversion, which are a common feature of the juvenile pattern when present in the anterior leads (9,22); however, less is known about age-related physiological ECG characteristics in adolescents. Santini et al (7) evaluated a substantial population of 24,062 high-school students, describing the anthropometric characteristics, baseline ECG findings, and FIGURE 2 | Heatmap correlation between individual features and ECG variables. Each square of the heatmap represents the correlation between the x-axis and the y-axis variables, which ranges between −1 and +1.…”

“…A recent meta-analysis (6) has shown that pediatric athletes have a greater prevalence of training-related and training-unrelated ECG changes than non-athletes, and the magnitude, prevalence, and distribution of such changes are dependent on the chronological age of the pediatric athlete. Limited data (7) exist on normal age-related ECG changes in adolescents between different age groups and no data have been published regarding the athletic population classed into age intervals of 2 years. We have already published echocardiographic reference values related to physiological remodeling of the adolescent athlete's heart in soccer players (8), therefore in this study, we aimed to establish normal, age-related electrocardiographic measurements (P wave duration, PR interval, QRS duration, and QT and QTc interval) in a large cohort of adolescent athletes according to age at 2-year intervals, and to provide nomograms to better define the pediatric athlete's heart.…”

Body size influences heart rate in children aged 6 to 18 years old

“…Santini et al [ 12 ] studied a large cohort of 24,062 students in high school, documenting the anthropometric parameters, baseline ECG findings, and principal clinical findings according to age groups divided by 2 years. The average HR decreased with age, ranging from 84 bpm at 12 to 13 years to 74 bpm at 18 to 19 years.…”