Age at start of endurance training is associated with patterns of left ventricular hypertrophy in middle-aged runners

Young endurance training starting age in non-elite athletes is associated with higher proximal aortic distensibility

Objective

Decreased proximal aortic distensibility (AD) is known to significantly predict all-cause mortality and cardiovascular events among individuals without overt cardiovascular disease. This cross-sectional study investigated the association of endurance training (ET) parameters, namely, ET starting age, ET years and yearly ET volume with AD in non-elite endurance athletes.

Methods

Healthy, normotensive, male Caucasian participants of a 10-mile race were assessed with a 2D echocardiogram and comprehensive interview. Ascending aortic diameters were measured simultaneously with pulse pressure. Aortic strain, AD and aortic stiffness index were calculated. Predictors of AD were investigated among training parameters by linear regression models corrected for age, resting heart rate, stroke volume index and mean blood pressure.

Results

Ninety-two of 121 athletes (aged 42±8 years) had sufficient echocardiogram quality and were used for analysis. ET starting age (range 6–52 years) and years of ET (range 2–46 years) were highly collinear and used in two separate models for AD. Significant factors for AD were ET starting age, 10-mile race time and resting heart rate in model I, and age, years of ET, 10-mile race time and heart rate in model II (all p<0.01).

Conclusions

In our cohort of healthy, non-elite, middle-aged runners, AD was significantly higher in athletes with younger ET starting age or more years of ET (in the model adjusted for confounders). In the model with years of ET, age had a negative contribution to AD, suggesting that with older age, the benefit of more years of ET on AD decreased. Future studies assessing the effect of exercise training on arterial properties should include training starting age.

Age-Related Electrocardiographic Characteristics of Male Junior Soccer Athletes

Introduction

Very limited data exist on normal age-related ECG variations in adolescents and no data have been published regarding the ECG anomalies induced by intensive training, which are relevant in pre-participation screening for sudden cardiac death prevention in the adolescent athletic population. The purpose of this study was to establish normal age-related electrocardiographic measurements (P wave duration, PR interval, QRS duration, QT, and QTc interval) grouped according to 2-year age intervals.

Methods

A total of 2,151 consecutive healthy adolescent Soccer athletes (trained for a mean of 7.2 ± 1.1 h per week, 100% male Caucasians, mean age 12.4 ± 1.4 years, range 7–18) underwent pre-participation screening, which included ECG and transthoracic echocardiography in a single referral center.

Results

Their heart rate progressively slowed as age increased (p < 0.001, ranging from 80.8 ± 13.2 to 59.5 ± 10.2 bpm), as expected. The P wave, PR interval, and QRS duration significantly increased in older age classes (p = 0.019, p = 0.001, and p < 0.001, respectively), and after Bonferroni's correction, the difference remained significant in all age classes for QRS duration. The QTc interval diminished progressively with increasing age (p = 0.003) while the QT interval increased progressively (p < 0.001).

Conclusions

Significant variations in the normal ECG characteristics of young athletes exist between different age groups related to increasing age and training burden, thus, age-specific reference values could be adopted, as already done for echocardiographic measurements, and may help to further discriminate potentially pathologic conditions.

Cardiac remodeling induced by exercise in Caucasian male master athletes: a cross-sectional study

To describe cardiac remodeling in a population of male master athletes evaluated by transthoracic echocardiography and to analyse its relationship with several exercise-related characteristics. A total of 105 male master athletes aged ≥ 40 years old, mostly involved in endurance sports (81.0%) with a median training-volume of 66 [44; 103] METs/h/week, were studied. Left ventricular end-diastolic and end-systolic volumes were above the references in 84.8% and 75.8% athletes, decreasing in frequency when adjusted for BSA (26.3% and 23.2%). LV geometry was changed in more than half of the athletes (eccentric hypertrophy 28.3%, concentric remodelling 15.2% and concentric hypertrophy 8.1%) and several right ventricular (RV) dimensions were increased. Left atrium was dilated in 53.5% and right atrium in 37.4% athletes; only one athlete had a dilated aorta. Mean LV ejection fraction was 61 ± 7% and global longitudinal strain - 18.3 ± 2.0%. Changes in LV geometry were more common in high intensity sports; LV dilation in athletes exercising > 10 h/week and in high intensity sports; RV dilation in athletes exercising > 66 MET-hour/week and in endurance sports. In multivariate analysis high intensity sports remained an independent predictor of changes in LV geometry. A significant proportion of male master athletes showed altered echocardiographic parameters compared to the reference values, more pronounced in those involved in endurance sports, with high intensity and high volume of exercise. This may correspond to exercise-induced physiological adaptations, reinforcing the concept that the characteristics of exercise are major determinants of cardiac remodeling and should be considered during athletes' evaluation.

Left Ventricular Systolic Function Assessed by Speckle Tracking Echocardiography in Athletes with and without Left Ventricle Hypertrophy

The aim of this study was to evaluate selected parameters of strain and rotation of the left ventricle (the basal rotation (BR) index, the basal circumferential strain (BCS) index, and the global longitudinal strain (GLS) of the left ventricle) in male athletes with physiological cardiac hypertrophy (LVH group), and athletes (non-LVH group) and non-athletes without hypertrophy (control group, CG). They were evaluated using transthoracic echocardiography and speckle tracking echocardiography before and after an incremental exercise test. The LVH group demonstrated lower BR at rest than the non-LVH group (p < 0.05) and the CG (p < 0.05). Physical effort had no effect on BR, nor was this effect different between groups (p > 0.05). There was a combined influence of LVH and physical effort on BR (F = 5.70; p < 0.05) and BCS (F = 4.97; p < 0.05), but no significant differences in BCS and GLS at rest between the groups. A higher BCS and lower GLS after exercise in the LVH group were demonstrated in comparison with the CG (p < 0.05). Left ventricular basal rotation as well as longitudinal and circumferential strains showed less of a difference between rest and after physical effort in subjects with significant myocardial hypertrophy. In conclusion, the obtained results may suggest that echocardiographic assessment of basal rotation and circumferential strain of the left ventricular can be important in predicting cardiac disorders caused by physical effort in individuals with physiological and pathological heart hypertrophy.