Physiologic limits of left ventricular hypertrophy in elite junior athletes: relevance to differential diagnosis of athlete's heart and hypertrophic cardiomyopathy

Left Ventricular Hypertrophy in Male and Female Judo Athletes

Changes in cardiac geometry develop after intense and prolonged training. Left ventricular enlargement, increased relative wall thickness, and growing mass of the left ventricle occur after strenuous exercise. Combat sports such as judo can lead to left ventricular hypertrophy. Previous studies have found that there are differences in left ventricular chamber size and thickness between the sexes, with female athletes having smaller wall diameters and less hypertrophy than male athletes. The research aims to examine heart muscle adaptations and remodeling of cardiac geometry among elite judo athletes and to evaluate differences between males and females. A cross-sectional study included a group of 19 (males n=10, females n=9) professional judokas between 20 and 30 years. Demographic and anthropometric data were collected. Cardiac geometry was determined by two-dimensional transthoracic echocardiography. In terms of left ventricular mass and the left ventricular mass index significant differences were found between male and female judokas (233.44±68.75 g vs. 164.11±16.59 g, p=0.009), (105.16±24.89 vs. 84.66±15.06, p=0.044), respectively. A greater enlargement of the heart muscle is observed in male athletes compared to the female group. Left ventricle enlargement is likely to occur among elite-level judokas.

Electrocardiographic manifestations in female team handball players: analyzing ECG changes in athletes

Introduction

Long-term intense training leads to structural, functional, and electrical remodeling of the heart. How different sports affect the heart has not been fully investigated, particularly for female athletes. The aim of the present study was to investigate the morphology of 12-lead resting electrocardiogram (ECG) in elite female handball players compared to non-athlete female subjects. Potential changes will be explored to see if they could be explained by differences in cardiac dimensions and exercise hours.

Materials and methods

A cross-sectional study of 33 elite female team handball players compared to 33 sex and age-matched, non-athletic controls (age range 18-26 years) was performed. All participants underwent a resting 12-lead ECG and an echocardiographic examination. ECG variables for left ventricular hypertrophy and durations were evaluated and adjusted for cardiac dimensions and exercise hours using ANCOVA analysis. A linear regression analysis was used to describe relation between echocardiographic and ECG measures and exercise hours.

Results

The female handball players had larger cardiac dimensions and significantly lower heart rate and QTc duration (Bazett's formula) as well as increased QRS and QT durations compared to controls. The 12-lead sum of voltage and the 12-lead sum of voltage ∗ QRS were significantly higher among handball players. Changes in ECG variables reflecting the left ventricle could in part be explained by left ventricular size and exercise hours. Correlation with exercise hours were moderately strong in most of the echocardiographic measures reflecting left ventricular (LV), left ventricular mass (LVM), left atrium (LA) and right atrium (RA) size. Poor to fair correlations were seen in the majority of ECG measures.

Conclusions

Female team handball players had altered ECGs, longer QRS and QT durations, higher 12-lead sum of voltage and 12-lead sum of voltage ∗ QRS as well as shorter QTc (Bazett's formula) duration compared to non-athletic controls. These findings could only partly be explained by differences in left ventricular size. Despite larger atrial size in the athletes, no differences in P-wave amplitude and duration were found on ECG. This suggest that both structural, and to some degree electrical remodeling, occur in the female team handball players' heart and highlight that a normal ECG does not rule out structural adaptations. The present study adds knowledge to the field of sports cardiology regarding how the heart in female team handball players adapts to this type of sport.

Distinguishing left ventricular hypertrophy from hypertrophic cardiomyopathy in adolescents: a longitudinal observation study

AIMS

Echocardiographic characteristics to distinguish physiological left ventricular (LV) hypertrophy from pathology are warranted in early adolescent athletes. This study aimed to explore the phenotype, progression, and potential grey zone of LV hypertrophy during adolescence in athletes and hypertrophic cardiomyopathy (HCM) genotype-positive patients.

METHODS AND RESULTS

In this longitudinal observation study, we compared seventy-six 12-year-old athletes with 55 age-matched and sex-matched HCM genotype-positive patients. Echocardiographic parameters were evaluated by using paediatric reference values (Z-scores). Hypertrophic cardiomyopathy genotype-positive patients were included if they had no or mild LV hypertrophy [maximum wall thickness <13 mm, Z-score <6 for interventricular septum diameter (ZIVSd), or posterior wall thickness]. We collected clinical data, including data on cardiac events. The mean follow-up-time was 3.2 ± 0.8 years. At baseline, LV hypertrophy was found in 28% of athletes and 21% of HCM genotype-positive patients (P = 0.42). Septum thickness values were similar (ZIVSd 1.4 ± 0.9 vs. 1.0 ± 1.3, P = 0.08) and increased only in HCM genotype-positive patients {ZIVSd progression rate -0.17 [standard error (SE) 0.05], P = 0.002 vs. 0.30 [SE 0.10], P = 0.001}. Left ventricular volume Z-scores (ZLVEDV) were greater in athletes [ZLVEDV 1.0 ± 0.6 vs. -0.1 ± 0.8, P < 0.001; ZLVEDV progression rate -0.05 (SE 0.04), P = 0.21 vs. -0.06 (SE 0.04), P = 0.12]. Cardiac arrest occurred in two HCM genotype-positive patients (ages 13 and 14), with ZIVSd 8.2-11.5.

CONCLUSION

Left ventricular hypertrophy was found in a similar proportion in early adolescence but progressed only in HCM genotype-positive patients. A potential grey zone of LV hypertrophy ranged from a septum thickness Z-score of 2.0 to 3.3. Left ventricular volumes remained larger in athletes. Evaluating the progression of wall thickness and volume may help clinicians distinguish physiological LV hypertrophy from early HCM.

Principal components analysis to evaluate complex association of polymorphisms in ACE and ACTN3 genes and the extent of cardiovascular adaptive changes in elite athletes

BACKGROUND

Present article aims at clarifying the association of ACE and ACTN3 polymorphisms with adaptive heart changes in elite athletes from power, endurance and mixed sport disciplines using the principal component analysis (PCA).

METHODS

Overall, 281 elite male athletes are divided into three groups: strength-type sports, endurance and mixed sports. After anthropometric measurements, physical and ultrasound examination of the heart, the athletes were exposed to a physical load test. All groups were analyzed for functional ACE and ACTN3 polymorphisms. In order to convert a set of examined, possibly correlated adaptive cardiovascular changes into a set of values of linearly uncorrelated variables we used principal component analysis (PCA).

RESULTS

The type of sport significantly affects not only the athlete's anthropometric characteristics, but also on the scope and specificity of the investigated adaptive cardiovascular changes. Athletes from the mixed group of sports showed the best working efficiency of the heart. PCA showed that the type of sport, but not genetic predisposition affects the co-adaptation of complex traits.

CONCLUSIONS

Effect of genotype, type of sport and their interaction on observed variability in morpho-functional cardiovascular adaptive changes in elite athletes can be used for a better understanding of the clinical phenomenon of athlete's heart and sudden cardiac death syndrome.

The athlete's heart: insights from echocardiography

The manifestations of the athlete's heart can create diagnostic challenges during an echocardiographic assessment. The classifications of the morphological and functional changes induced by sport participation are often beyond 'normal limits' making it imperative to identify any overlap between pathology and normal physiology. The phenotype of the athlete's heart is not exclusive to one chamber or function. Therefore, in this narrative review, we consider the effects of sporting discipline and training volume on the holistic athlete's heart, as well as demographic factors including ethnicity, body size, sex, and age.

Relating QRS voltages to left ventricular mass and body composition in elite endurance athletes

PURPOSE

Electrocardiogram (ECG) QRS voltages correlate poorly with left ventricular mass (LVM). Body composition explains some of the QRS voltage variability. The relation between QRS voltages, LVM and body composition in endurance athletes is unknown.

METHODS

Elite endurance athletes from the Pro@Heart trial were evaluated with 12-lead ECG for Cornell and Sokolow-Lyon voltage and product. Cardiac magnetic resonance imaging assessed LVM. Dual energy x-ray absorptiometry assessed fat mass (FM) and lean mass of the trunk and whole body (LBM). The determinants of QRS voltages and LVM were identified by multivariable linear regression. Models combining ECG, demographics, DEXA and exercise capacity to predict LVM were developed.

RESULTS

In 122 athletes (19 years, 71.3% male) LVM was a determinant of the Sokolow-Lyon voltage and product (β = 0.334 and 0.477, p < 0.001) but not of the Cornell criteria. FM of the trunk (β = - 0.186 and - 0.180, p < 0.05) negatively influenced the Cornell voltage and product but not the Sokolow-Lyon criteria. DEXA marginally improved the prediction of LVM by ECG (r = 0.773 vs 0.510, p < 0.001; RMSE = 18.9 ± 13.8 vs 25.5 ± 18.7 g, p > 0.05) with LBM as the strongest predictor (β = 0.664, p < 0.001). DEXA did not improve the prediction of LVM by ECG and demographics combined and LVM was best predicted by including VO₂max (r = 0.845, RMSE = 15.9 ± 11.6 g).

CONCLUSION

LVM correlates poorly with QRS voltages with adipose tissue as a minor determinant in elite endurance athletes. LBM is the strongest single predictor of LVM but only marginally improves LVM prediction beyond ECG variables. In endurance athletes, LVM is best predicted by combining ECG, demographics and VO₂max.

A New Tool to Aid the Differential Diagnosis of Physiological Remodelling from Cardiac Pathology When Assessing Left Ventricle, Left Atrial and Aortic Structure and Function in Male Arab and Black Paediatric Athletes

Aim: To determine if published Z-scores for left ventricular (LV), left atrial (LA) and aortic structure as well as indices of LV function (Doppler and TDI) in paediatric athletes and non-athletes are appropriate for application in male Arab and black paediatric athletes. If inappropriate, we aim to provide new nomograms and Z-scores for clinical application. Methods: 417 (297 Arab, 120 black) male paediatric (11-18 years) athletes, were evaluated by 2D echocardiography as per British Society of Echocardiography recommendations, and biological age (by radiological X-ray) assessment. Z-scores were tested by residual and correlation analysis together with visual inspection. New Z-scores involved allometric (a*BSA(b+c*chronological age)) and second-order polynomial (y=a*chronological age2+b*chronological age+c) equations for measures of cardiac size and indices of LV function, respectively. Results: Residual linear regression, correlation analysis and visual inspection revealed published z-scores in white peri-pubertal footballers and paediatric non-athletes to be inappropriate for application in male Arab and black paediatric athletes. Residual linear regression revealed new Z-scores for measures of LV, LA and aortic root size to be independent of BSA, ethnicity, chronological and biological age. Residual linear regression revealed new Z-scores for measures of function to be independent of chronological age. Conclusion: Our new z-scores may aid differential diagnosis of suspected pathology versus physiology remodelling, in cardiac screening of the Arab and black paediatric athlete. Nomograms are provided to assist the tracking of the paediatric athlete necessitating annual follow-up and Excel z-score calculation to facilitate use in day-to-day practice.

Influence of training status on cardiac and vascular functioning in young recreational and competitive male rowers

Introduction

The aim of the study was to investigate the influence of training status on cardiovascular function in young male recreational and competitive rowers.

Methods

Ejection duration in percentage to the heart rate period (ED%), subendocardial viability ratio (SEVR), augmentation index at 75 bpm (AIx75) and carotid to femoral pulse wave velocity (cf-PWV) of competitive rowers (CR) (age 17.6 ± 4.1 years), recreational rowers (RR) (age 16.7 ± 2.70 years) and athletes practicing other recreational sports (ORS) (age 15.3 ± 1.4 years) were assessed.

Results

ED% was lower in CR compared to ORS (31.9 ± 3.9% vs. 38.4 ± 4.8%; p = 0.026) and cf-PWV was higher in CR compared to ORS (5.5 ± 1.0 m/s vs. 4.7 ± 0.5 m/s; p = 0.032). SEVR was higher in CR compared to RR and ORS (165.8 ± 33.7% vs. 127.4 ± 30.4% and 128.3 ± 27.8%; p = 0.022) and AIx75 was lower in CR compared to RR and ORS (-15.7 ± 8.6% vs. 1.2 ± 9.9% and 1.5 ± 9.1; p = 0.001).

Discussion

Healthy, young competitive male rowers reported higher myocardial performance and better cardiovascular health than recreational athletes. Interpretations of cf-PWV in competitive rowers should be performed alongside other cardiovascular indicators.

Young athlete's growing heart: sex differences in cardiac adaptation to exercise training during adolescence

BACKGROUND

Athlete's heart is a condition of exercise-induced cardiac remodelling. Adult male endurance athletes more often remodel beyond reference values. The impact of sex on remodelling through adolescence remains unclear. Paediatric reference values do not account for patient sex or exercise history. We aimed to study the effect of sex on cardiac remodelling throughout adolescence.

METHODS

We recruited 76 male (M) and female (F) 12-year-old cross-country skiers in a longitudinal cohort study. Echocardiography was performed and analysed according to guidelines at age 12 (48 M, 28 F), 15 (34 M, 14 F) and 18 (23 M, 11 F). Repeated echocardiographic measurements were analysed by linear mixed model regression.

RESULTS

Males displayed greater indexed left ventricular end-diastolic volumes (LV EDVi) from age 12 (M 81±7 vs F 76±7, mL/m², p≤0.01), and progressed further until follow-up at age 18 (M 2.3±9.7 vs F -3.9±4.5 ΔmL/m², p≤0.01). LV EDVi remained above adult upper reference values in both groups. Males increased LV Mass Index from age 12 to 18 (M 33±27 vs F 4±19, Δg/m², p≤0.01). Males displayed LV mass above paediatric reference values at ages 15 and 18. A subset of males (35%) and females (25%) displayed wall thickness above paediatric reference values at age 12. Cardiac function was normal. There was no sex difference in exercise hours.

CONCLUSION

Sex-related differences in athlete's heart were evident from age 12, and progressed throughout adolescence. Remodelling beyond reference values was more frequent than previously reported, particularly affecting males. Age, sex and exercise history may assist clinicians in distinguishing exercise-induced remodelling from pathology in adolescents.

Certainties and Uncertainties of Cardiac Magnetic Resonance Imaging in Athletes

Prolonged and intensive exercise induces remodeling of all four cardiac chambers, a physiological process which is coined as the “athlete’s heart”. This cardiac adaptation, however, shows overlapping features with non-ischemic cardiomyopathies, such as dilated, arrhythmogenic and hypertrophic cardiomyopathy, also associated with athlete’s sudden cardiac death. Cardiac magnetic resonance (CMR) is a well-suited, highly reproducible imaging modality that can help differentiate athlete’s heart from cardiomyopathy. CMR allows accurate characterization of the morphology and function of cardiac chambers, providing full coverage of the ventricles. Moreover, it permits an in-depth understanding of the myocardial changes through specific techniques such as mapping or late gadolinium enhancement. In this narrative review, we will focus on the certainties and uncertainties of the role of CMR in sports cardiology. The main aspects of physiological adaptation due to regular and intensive sports activity and the application of CMR in highly trained athletes will be summarized.

Energetic Contributions Including Gender Differences and Metabolic Flexibility in the General Population and Athletes

Metabolic flexibility includes the ability to perform fat and carbohydrate oxidation, as well as oxidative capacity, which is associated with mitochondrial function, energetic contributions, and physical health and performance. During a session of graded incremental exercise testing (GIET), we investigated metabolic flexibility, the contributions of three energy systems, and performances of individuals with different metabolic characteristics. Fifteen general population (GP; n = 15, male n = 7, female n = 8) and 15 national-level half-marathon and triathlon athletes (A; n = 15, male n = 7, female n = 8) participated in this study. During GIET, heart rate (HR), oxygen uptake (V˙O_2mean and V˙CO_2mean), metabolic equivalents (METs) in V˙O_2mean, and blood glucose and lactate concentrations (La⁻) were measured. Furthermore, jogging/running speeds (S) at specific La⁻, fat and carbohydrate oxidations (FATox and CHOox), and energetic contributions (oxidative; W_Oxi, glycolytic; W_Gly, and phosphagen; W_PCr) were calculated. The percentages of HR_max, relative V˙O_2mean, V˙CO_2mean, and METs in V˙O_2mean were all lower in A than they were in GP. FATox values were lower in GP than in A, while CHOox and La⁻ were higher in GP than in A. Negative correlations between La⁻ and FATox were also observed in both groups. Contributions of W_Oxi, W_Gly, and W_PCr were higher in GP than in A during GIET. Moreover, values of W_Gly, and W_PCr were significantly lower and higher, respectively, in male GP than in female GP. Furthermore, S at specific La⁻ were higher in A than in GP. It is suggested that an individualized low-intensity recovery exercise program be established, to achieve increased metabolic flexibility and oxidative capacity (aerobic base), such as public health improvements and a greater volume of higher exercise intensities; this is the type of exercise that elite athletes worldwide mostly perform during their training period and progression. This may prevent cardiac/metabolic diseases in GP.

Training intensity influences left ventricular dimensions in young competitive athletes

Background

In young athletes, exercise causes changes in the heart that include growth in wall thickness and mass of the left ventricle and expansion of the heart’s chambers. The heart’s function is either preserved or enhanced, but this may change to the opposite over time.

Objective

This study aimed to assess structural and functional cardiac adaptations in relation to exercise training time, intensity, and performance in young competitive athletes.

Methods

A total of 404 children and adolescents (14.23 ± 2.0 years, 97 females) were enrolled in the Munich Cardiovascular Adaptations in Young Athletes Study (MuCAYA-Study). Eighty-five participants were examined two times a year. Two-dimensional echocardiography was performed to assess left ventricular structure and function. Training time and intensity was measured with the MoMo physical activity questionnaire, maximum aerobic capacity by cardiopulmonary exercise testing, and strength with the handgrip strength test.

Results

Maximum aerobic capacity significantly influenced interventricular septal thickness in diastole. Training intensity significantly influenced left ventricular internal diameter in diastole and systole, and left ventricular mass indexed to body surface area. Within one year, interventricular wall thickness, relative wall thickness and left ventricular mass, indexed to body surface area and height, increased significantly. Training intensity and aerobic capacity contributed to cardiac adaptations in young competitive athletes, as represented by altered structural parameters but preserved cardiac function. Within a year, however, structural changes and a decline in diastolic performance were observed within the longitudinal sub-sample.

Conclusion

Our results confirm the hypothesis that cardiac adaptations to exercise occur at a young age. Cardiac adaptation in our cohort was influenced by exercise intensity and maximum aerobic capacity.

Role of the electrocardiogram in differentiating genetically determined dilated cardiomyopathy from athlete's heart

BACKGROUND

Physiological cardiac remodelling in highly trained athletes may overlap with dilated cardiomyopathy (DCM).

OBJECTIVES

The aim of this study was to investigate the role of the electrocardiogram (ECG) in differentiating between physiological and pathological remodelling.

METHODS

The study population consisted of 30 patients with DCM who revealed a pathogenic variant at genetic testing and 30 elite athletes with significant cardiac remodelling defined by a left ventricular (LV) end-diastolic diameter >62 mm and/or LV ejection fraction between 45% and 50%.

RESULTS

The ECG was abnormal in 22 (73%) patients with DCM. The most common abnormalities were low voltages (n = 14, 47%), lateral T-wave inversion (TWI) (n = 6, 20%), ventricular ectopic beats (n = 5, 17%) and anterior TWI (n = 4, 13). Two athletes revealed an abnormal ECG: complete left bundle branch block (LBBB) in one case and atrial flutter in the other. The sensitivity, specificity and accuracy of the ECG in differentiating DCM from physiological adaptation to exercise in athletes was 73% (confidence interval [CI]: 54%-88%), 93% (CI: 78%-99%) and 0.83 (CI: 0.71-0.92) respectively.

CONCLUSIONS

While the ECG is usually normal in athletes exhibiting significant LV dilatation and/or systolic dysfunction, this test is often abnormal in patients with DCM harbouring a pathogenic variant. Low voltages in the limb leads and lateral TWI are the most common abnormalities.

Echocardiographic Characterization of Left Heart Morphology and Function in Highly Trained Male Judo Athletes

The long-term practice of judo can lead to various changes in the heart including increased dimensions of the left ventricle in diastole and thickening of the interventricular septum and the posterior wall of the left ventricle. This study aimed to assess left ventricular morphology and function in elite male judokas. A comparative cross-sectional study was conducted that included a total of 20 subjects, 10 judokas, and 10 healthy non-athletes aged 24 ± 2.85 years. Demographic and anthropometric data were analyzed. All subjects underwent a medical examination and a two-dimensional transthoracic echocardiogram. Different parameters of left ventricular morphology and function were measured and compared between athletes and non-athletes. Left ventricle mass and LV mass index were higher in judokas than in non-athletes (p < 0.05), as well as PW thickness (9.78 ± 0.89 mm vs. 8.95 ± 0.76 mm). A total of six (n = 6) of athletes had eccentric hypertrophy, while others had normal heart geometry. LVEDd, LVEDs, LVEDd/BSA, and LVEDs/BSA were significantly higher in judokas (p < 0.05). LVEDd in athletes ranged from 48 to 62 mm. These values, combined with normal diastolic function, ejection fraction, and shortening fraction, indicate that the judokas’ cardiac adaptation was physiological rather than pathological.

Athlete's Heart Assessed by Sit-Up Strength Exercises in Military Men and Women: The CHIEF Heart Study

Background

Greater changes in cardiac structure and function in response to physical training have been observed more often in male athletes than in female athletes compared with their sedentary controls. However, studies for the sex-specific cardiac remodeling related to strength exercises in Asian athletes are rare.

Methods

This study included 580 men and 79 women, with an average age of 25 years, for a 6-month military training program in Taiwan. Both men and women attended a 2-min sit-up test to assess muscular strength after the training. The test performance falling one standard deviation above the mean (16%) was to define the superior eliteness of athletes. Cardiac structure and function were investigated by electrocardiography and echocardiography for men and women. Multiple logistic regression was used to determine the predictors of elite athlete status.

Results

In men, greater QTc interval, left ventricular mass adjusted to body surface area (LVMI), lateral mitral E'/A' ratio and right ventricular systolic pressure, and lower diastolic blood pressure were independent predictors of elite strength athletes in the sit-up test [odds ratio (OR) and 95% confidence intervals: 1.01 (1.00, 1.02), 1.02 (1.00, 1.04), 1.45 (1.06, 1.98), 1.13 (1.06, 1.23), and 0.96 (0.93, 0.99), respectively. In contrast, in women, the greater right ventricular outflow tract dimension was the only independent predictor of elite strength athletes in the sit-up test [OR: 1.26 (1.04, 1.53)].

Conclusions

In the 2-min sit-up test, cardiac characteristics differ between elite male and female athletes. While greater QTc interval, LVMI, and diastolic function of left ventricle predict the eliteness of male strength athletes, greater right ventricular chamber size characterizes elite female strength athletes.

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.

Athlete Heart in Children and Young Athletes. Echocardiographic Findings in 331 Cases

The changes of the athlete's heart are not well defined and characterized in children. We aimed to describe the morphological changes of the heart related to sport in young athletes. We evaluated a group of 331 young athletes under 18 years (mean 11.9 ± 3.2) who practice tennis: 58 (16.52%), football: 118 (33.62%), basketball: 16 (4.56%), athletics: 40 (11.4%), and swimming: 99 (28.21%). Type of sport, years of practice, and duration of the training were collected. All children underwent echocardiography with the following M-mode parameters: left atrium diameter (LAD), interventricular septum (IVS), and left ventricle posterior Wall (LVPW), diastolic diameter of the left ventricle (LVDD), and right ventricle outflow tract (RVOT). The major finding of our study was that 20% of the children had a Z score > 2 for the IVS and that increased to 30% for the children playing tennis or swimming. Also, other changes like LA and RVOT dilatation were observed in about 10 and 14% of the cases, respectively. Taken together, these figures indicate that cardiac remodeling is frequent in children. Further studies are needed to establish consensus-based criteria of athlete's heart in young children.

Left ventricular hypertrophy in athletes, a case-control analysis of interindividual variability

BACKGROUND

A variability in cardiac remodeling is observed in athletes regardless of age, sex, body size and sport participated. We sought to investigate whether other individual characteristics could affect the extent of Left ventricular hypertrophy (LVH).

METHODS

From 2120 consecutive Olympic athletes, those with LVH (defined as LV Wall thickness ≥ 13 mm) were matched 1:1 by age, gender, body surface area and type of sport with non-LVH Athletes. Clinical and Echocardiographic variables were compared.

RESULTS

48 athletes with LVH (2.3%) and 48 matched non-LVH athletes were identified. LVH Athletes had higher body weight (90 ± 18 vs 81 ± 11Kg; p = 0.006) body mass index (26 ± 2 vs 24 ± 2 Kg/m2; p < 0.001) and body fat percentage (15 ± 7% vs 12 ± 4%; p = 0.016) compared to non-LVH Athletes. They also had higher systolic (123 ± 1 vs 116 ± 11 mmHg; p = 0.002) and diastolic blood pressure (76 ± 8 vs 71 ± 9 mmHg; p = 0.002). On exercise testing, LVH Athletes reached a lower index workload (3.7 ± 0.9 vs 4.1 ± 0.8 W/Kg; p = 0.013) and a higher peak diastolic blood pressure (79 ± 10 vs 74 ± 11 mmHg; p = 0.012) than those without LVH. Binary logistic regression analysis showed that diastolic blood pressure (OR 1.052; 95% CI from 1.011 to 1.130; p = 0.020) and BMI (OR 1.220; 95% CI from 1.016 to 1.465; p = 0.033) had the strongest association with LVH as categorical variable.

CONCLUSIONS

Our study showed that increased blood pressure at rest and during exercise, together with larger body weight, body mass and fat percentage are associated with a higher degree of LVH, which is not associated with a greater physical performance and therefore possibly disproportionate to the sport activity.

Electrocardiographic and Echocardiographic Findings in Elite Ghanaian Male Soccer Players

OBJECTIVE

To analyze the athlete's heart of adult and adolescent elite male soccer players by electrocardiography (ECG) and echocardiography (ECHO) and to describe typical ECG and ECHO findings in this cohort (West African elite soccer players).

DESIGN

A cross-sectional study of ECGs and ECHOs conducted as part of precompetition medical assessment for national male soccer teams preparing for various Fédération Internationale de Football Association (FIFA) tournaments in 2016 and 2017.

SETTING

Ghana National Football Association.

PARTICIPANTS

One hundred fifty-nine players playing for the National male soccer teams preparing for tournaments in 2016 and 2017.

INTERVENTIONS

Precompetition medical assessment using ECGs and ECHOs.

MAIN OUTCOME MEASURES

Number of athletes with abnormal ECGs and ECHO findings.

RESULTS

Twenty-three percent of the players had abnormal ECGs. Nine percent of the participants had T-wave inversions in lateral leads (V5-V6). Sokolow-Lyon criteria for left ventricular hypertrophy were present in 64% of participants. Thirty-six (23%) players had left ventricular wall thickness (LVWT) ≥13 mm, with no player exceeding 16 mm. Four percent of players had left ventricular cavity dimension greater than 60 mm. Relative wall thickness >0.42 was present in 44% of the players.

CONCLUSIONS

Uncommon ECG changes seem to be more common in elite Ghanaian soccer players compared with previously reported results for Caucasians and even mixed populations of black athletes. Although ST elevation, T-wave inversions, and LVWT up to 15 mm are common, ST depression, deep T-waves in lateral leads, and LVWT ≥16 mm always warrant further clinical and scientific investigations.

Benefits and limitations of electrocardiographic and echocardiographic screening in top level endurance athletes

The study was designed to assess the usefulness of routine electrocardiography (ECG) as well as transthoracic echocardiography (TTE) in screening top level endurance athletes. An additional goal was to attempt to identify factors determining occurrence of adaptive and abnormal changes in ECG and TTE. The retrospective analysis included basic medical data, ECG and TTE results of 262 athletes (123 rowers, 32 canoeists and 107 cyclists), members of the Polish National Team. The athletes were divided into two age groups: young (≤ 18 years; n = 177) and elite (> 18 years; n = 85). ECG and TTE measurements were analysed according to the International Recommendations from 2017 and 2015, respectively. Adaptive ECG changes were found in 165 (63%) athletes. Abnormal ECG changes were identified in 10 (3.8%) athletes. 98% of athletes exceeded TTE norms for the general population and 26% exceeded norms for athletes. The occurrence of both adaptive ECG findings and abnormalities in the TTE (in norms for athletes) was strongly associated with the years of training, hours of training per week and the age of the athlete. Male gender and the years of training were independent predictors of the ECG and TTE findings. Abnormal ECG changes were not related to the time of sport. Among 10 athletes with ECG changes, only 3 had changes in TTE and no relationship was found between abnormal finding in ECG and TTE (p = 0.45). ECG and TTE screening complement each other in identifying endurance athletes requiring treatment or verification. Unlike abnormal ECG changes, adaptive ECG changes and TTE abnormalities are strongly related to the training duration, which reflects physiological adaptation of the heart to physical exertion in high endurance athletes.

Effect of aerobic exercise on physiological and left ventricular echocardiographic characteristics of non-athletic adult males in Northern Ethiopia

BACKGROUND

Regular aerobic exercise can induce alterations in structural and hemodynamic physiology of the heart in both athletic and nonathletic populations. This is because due to cardiac adaptation to exercise improves cardiac workout capacity by increasing left ventricular function. The aim of the present study was to examine the effect of aerobic exercise on blood pressure and left ventricular structural and myocardial function in Ethiopian non-athletic males.

METHODS

Twenty male adults (aged 19-23 years) were recruited and they were engaged in aerobic exercise training for 3 months (3days/week, 50-75%MHR). Selected participants underwent standard transthoracic doppler echocardiographic examinations before and after intervention of the exercise training. Collected data were analyzed through Paired Sample T test using IBM SPSS version 21 statistical software with significance level set at p<0.05.

RESULTS

Finding of the study indicated that significant reduction in systolic and diastolic blood pressure was observed after exercise training (p<0.05). Improvement was recorded in PWT (7.4±0.94mm vs 7.95±0.61mm, p=0.017) and IVST (7.95±0.83mm vs 8.25±0.72mm, p=0.030) while significant reduction was recorded in LVIDS (33.85±0.99mm vs 32.45±2.04mm, p=0.002). Aerobic exercises also induced significant improvement on left ventricular myocardial function parameters (p<0.05) in end diastolic volume (95.8±8.4ml vs 100.45±11.42ml), stroke volume (52.55±7.12ml vs 58.15±11.18ml) and ejection fraction (54.73±4.11 vs 57.53±6.2). However, exercise didn't stimulate significant change in the internal diameter at end diastole (0.086), end systolic volume (p=0.173) and cardiac output (p=0.13).

CONCLUSIONS

Aerobic exercise induces structural and myocardial physiological changes within the left ventricle in Ethiopian non-athletic young adult males.

Sudden Death in the Young: Information for the Primary Care Provider

There are multiple conditions that can make children prone to having a sudden cardiac arrest (SCA) or sudden cardiac death (SCD). Efforts have been made by multiple organizations to screen children for cardiac conditions, but the emphasis has been on screening before athletic competition. This article is an update of the previous American Academy of Pediatrics policy statement of 2012 that addresses prevention of SCA and SCD. This update includes a comprehensive review of conditions that should prompt more attention and cardiology evaluation. The role of the primary care provider is of paramount importance in the evaluation of children, particularly as they enter middle school or junior high. There is discussion about whether screening should find any cardiac condition or just those that are associated with SCA and SCD. This update reviews the 4 main screening questions that are recommended, not just for athletes, but for all children. There is also discussion about how to handle post-SCA and SCD situations as well as discussion about genetic testing. It is the goal of this policy statement update to provide the primary care provider more assistance in how to screen for life-threatening conditions, regardless of athletic status.

Hypertrophic Cardiomyopathy: Updates Through the Lens of Sports Cardiology

Purpose of review

This review will summarize the distinction between hypertrophic cardiomyopathy (HCM) and exercise-induced cardiac remodeling (EICR), describe treatments of particular relevance to athletes with HCM, and highlight the evolution of recommendations for exercise and competitive sport participation relevant to individuals with HCM.

Recent findings

Whereas prior guidelines have excluded individuals with HCM from more than mild-intensity exercise, recent data show that moderate-intensity exercise improves functional capacity and indices of cardiac function and continuation of competitive sports may not be associated with worse outcomes. Moreover, recent studies of athletes with implantable cardioverter defibrillators (ICDs) demonstrated a safer profile than previously understood. In this context, the updated American Heart Association/American College of Cardiology (AHA/ACC) and European Society of Cardiology (ESC) HCM guidelines have increased focus on shared decision-making and liberalized restrictions on exercise and sport participation among individuals with HCM.

Summary

New data demonstrating the safety of exercise in individuals with HCM and in athletes with ICDs, in addition to a focus on shared decision-making, have led to the most updated guidelines easing restrictions on exercise and competitive athletics in this population. Further athlete-specific studies of HCM, especially in the context of emerging therapies such as mavacamten, are important to inform accurate risk stratification and eligibility recommendations.

Echocardiographic evaluation of the Athlete's heart

Cardiac response to prolonged, intense exercise induces phenotypic and physiologic adaptive changes that improve myocardial ability to meet oxygen demands. These adaptations, termed "athletes' heart," have been extensively studied. The importance of this entity arises from the increasing numbers of athletes as well as the drive for physical fitness in the general population leading to adaptive cardiac changes that need to be differentiated from life-threatening cardiovascular diseases. A number of pathologic entities may share phenotypic changes with the athletes' heart such as hypertrophic cardiomyopathy, dilated cardiomyopathy, Marfan's syndrome, and arrhythmogenic right ventricular cardiomyopathy. Cardiologists need to be cognizant of these overlapping findings to appropriately diagnose diseases and prevent catastrophic outcomes especially in young and healthy individuals who may not show any symptoms until they engage in intense exercise. It is equally important to recognize and distinguish normal, exercise-adaptive cardiac changes to provide accurate screening and guidance to young elite athletes. Echocardiography is a valuable modality that allows comprehensive initial evaluation of cardiac structures, function, and response to exercise. Several different echocardiographic techniques including M-Mode, 2D echo, Doppler, tissue Doppler, color tissue Doppler, and speckle tracking have been used in the evaluation of cardiac adaptation to exercise. The following discussion is a review of literature that has expanded our knowledge of the athlete's heart.

Improved Carotid Elasticity but Altered Central Hemodynamics and Carotid Structure in Young Athletes

Young athletes most often exceed the physical activity recommendations of the World Health Organization. Therefore, they are of special interest for investigating cardiovascular adaptions to exercise. This study aimed to examine the arterial structure and function of young athletes 12-17 years old and compare these parameters to reference values of healthy cohorts. Carotid intima-media thickness (cIMT), carotid diameter, cIMT÷carotid diameter-ratio (cIDR), arterial compliance (AC), elastic modulus (Ep), β stiffness index (β), and carotid pulse wave velocity (PWVβ) were determined using ultrasound in 331 young athletes (77 girls; mean age, 14.6 ± 1.30 years). Central systolic blood pressure (cSBP) and aortic PWV (aPWV) were measured using the oscillometric device Mobil-O-Graph. Standard deviation scores (SDS) of all parameters were calculated according to German reference values. The 75th and 90th percentiles were defined as the threshold for elevated cIMT and arterial stiffness, respectively. Activity behavior was assessed with the MoMo physical activity questionnaire, and maximum power output with a standard cardiopulmonary exercise test. One-sample t-tests were performed to investigate the significant deviations in SDS values compared to the value "0". All subjects participated in competitive sports for at least 6 h per week (565.6 ± 206.0 min/week). Of the 331 young athletes, 135 (40.2%) had cIMT >75th percentile, 71 (21.5%) had cSBP >90th percentile, and 94 (28.4%) had aPWV>90th percentile. We observed higher cIMT SDS (p < 0.001), cIDR SDS (p = 0.009), and AC SDS (p < 0.001) but lower β SDS (p < 0.001), Ep SDS (p < 0.001), and PWVβ SDS (p < 0.001) compared to the reference cohort. The cSBP SDS (p < 0.001) and aPWV SDS (p < 0.001) were elevated. In conclusion, cIMT and cIDR were higher in young athletes than in a reference cohort. Furthermore, young athletes presented better carotid elasticity and lower arterial stiffness of the carotid artery. However, central arterial stiffness was higher compared to the reference cohort. The thickening of the carotid intima-media complex in combination with a reduction in arterial stiffness indicates a physiological adaptation to exercise in youth.

Recommendations on Youth Participation in Ultra-Endurance Running Events: A Consensus Statement

Participation in ultra-endurance running (UER) events continues to grow across ages, including youth athletes. The 50- and 100-km are the most popular distances among youth athletes. Most youth athletes are between 16-18 years; however, some runners younger than 12 years have successfully completed UER events. Parents, athletes, coaches, race directors, and medical professionals often seek advice regarding the safety of youth athletes participating in these events, especially with regard to potential short and long-term health consequences. UER may impact key organ systems during growth and development. We propose a decision-making process, based on current knowledge and the experience of the consensus group that addresses age regulations, medical and psychological well-being, training status and race-specific factors (such as distance, elevation change, remoteness, ambient temperatures, level of medical assistance, and type of provisions provided by the race organizers) to use until evidence of long-term consequences of UER in youth athletes is available. These recommendations are aimed at safe participation in UER events for youth athletes with a proper and individualized assessment.

Cardiac Structure and Function in Elite Female and Male Soccer Players

Importance

Population-specific normative data are essential for the evaluation of competitive athletes. At present, there are limited data defining normal electrocardiographic (ECG) and echocardiographic values among elite US soccer players.

Objective

To describe ECG and echocardiographic findings in healthy elite US soccer players.

Design, Setting, and Participants

This cross-sectional study analyzed Fédération Internationale de Football Association-mandated screening sessions performed at US Soccer National Team training locations from January 2015 to December 2019. US women's and men's national team soccer players undergoing mandated cardiovascular screening were included.

Main Outcomes and Measures

Normal training-related and abnormal ECG findings were reported using the International Recommendations for Electrocardiographic Interpretation in Athletes. Echocardiographic measurements of structural and functional parameters relevant to cardiovascular remodeling were assessed relative to American Society of Echocardiography guideline-defined normal ranges.

Results

A total of 238 athletes (122 [51%] female; mean [SD] age, 20 [4] years; age range, 15-40 years) were included. Male athletes demonstrated a higher prevalence of normal training-related ECG findings, while female athletes were more likely to have abnormal ECG patterns (14 [11%] vs 0 in male cohort), largely accounted for by abnormal T-wave inversions. Echocardiography revealed no pathologic findings meeting criteria for sport restriction, but athletes frequently exceeded normal ranges for structural cardiac parameters responsive to exercise-induced remodeling including body surface area-indexed left ventricular (LV) mass (58 of 113 female athletes [51%] and 67 of 114 male athletes [59%]), indexed LV volume (89 of 115 female athletes [77%] and 76 of 111 male athletes [68%]), and LV wall thickness (37 of 122 female athletes [30%] and 47 of 116 male athletes [41%]). Age-stratified analysis revealed age-dependent increases in LV wall thickness, mass, and volumes among female athletes and LV wall thickness and mass among male athletes.

Conclusions and Relevance

These data represent the first set of comprehensive normative values for elite US soccer players and one of the largest sport-specific echocardiographic remodeling studies in female athletes. Abnormal ECG findings were more common in female athletes, while both female and male athletes frequently exceeded clinical normality cut points for remodeling-associated echocardiographic parameters.

Association of Ascending Aortic Dilatation and Long-term Endurance Exercise Among Older Masters-Level Athletes

Importance

Aortic dilatation is frequently encountered in clinical practice among aging endurance athletes, but the distribution of aortic sizes in this population is unknown. It is additionally uncertain whether this may represent aortic adaptation to long-term exercise, similar to the well-established process of ventricular remodeling.

Objective

To assess the prevalence of aortic dilatation among long-term masters-level male and female athletes with about 2 decades of exercise exposure.

Design, Setting, and Participants

This cross-sectional study evaluated aortic size in veteran endurance athletes. Masters-level rowers and runners aged 50 to 75 years were enrolled from competitive athletic events across the United States from February to October 2018. Analysis began January 2019.

Exposures

Long-term endurance exercise.

Main Outcomes and Measures

The primary outcome was aortic size at the sinuses of Valsalva and the ascending aorta, measured using transthoracic echocardiography in accordance with contemporary guidelines. Aortic dimensions were compared with age, sex, and body size-adjusted predictions from published nomograms, and z scores were calculated where applicable.

Results

Among 442 athletes (mean [SD] age, 61 [6] years; 267 men [60%]; 228 rowers [52%]; 214 runners [48%]), clinically relevant aortic dilatation, defined by a diameter at sinuses of Valsalva or ascending aorta of 40 mm or larger, was found in 21% (n = 94) of all participants (83 men [31%] and 11 women [6%]). When compared with published nomograms, the distribution of measured aortic size displayed a rightward shift with a rightward tail (all P < .001). Overall, 105 individuals (24%) had at least 1 z score of 2 or more, indicating an aortic measurement greater than 2 SDs above the population mean. In multivariate models adjusting for age, sex, body size, hypertension, and statin use, both elite competitor status (rowing participation in world championships or Olympics or marathon time under 2 hours and 45 minutes) and sport type (rowing) were independently associated with aortic size.

Conclusions and Relevance

Clinically relevant aortic dilatation is common among aging endurance athletes, raising the possibility of vascular remodeling in response to long-term exercise. Longitudinal follow-up is warranted to establish corollary clinical outcomes in this population.

Screening of Potential Cardiac Involvement in Competitive Athletes Recovering From COVID-19: An Expert Consensus Statement

As our understanding of the complications of coronavirus disease-2019 (COVID-19) evolve, subclinical cardiac pathology such as myocarditis, pericarditis, and right ventricular dysfunction in the absence of significant clinical symptoms represents a concern. The potential implications of these findings in athletes are significant given the concern that exercise, during the acute phase of viral myocarditis, may exacerbate myocardial injury and precipitate malignant ventricular arrhythmias. Such concerns have led to the development and publication of expert consensus documents aimed at providing guidance for the evaluation of athletes after contracting COVID-19 in order to permit safe return to play. Cardiac imaging is at the center of these evaluations. This review seeks to evaluate the current evidence regarding COVID-19-associated cardiovascular disease and how multimodality imaging may be useful in the screening and clinical evaluation of athletes with suspected cardiovascular complications of infection. Guidance is provided with diagnostic "red flags" that raise the suspicion of pathology. Specific emphasis is placed on the unique challenges posed in distinguishing athletic cardiac remodeling from subclinical cardiac disease. The strengths and limitations of different imaging modalities are discussed and an approach to return to play decision making for athletes post-COVID-19, as informed by multimodality imaging, is provided.

Characterisation of LV myocardial exercise function by 2-D strain deformation imaging in elite adolescent footballers

Purpose

Few data exist on the descriptions of LV myocardial mechanics and reserve during dynamic exercise of adolescent athletes. The aim of this study was to describe the LV myocardial and cardiopulmonary changes during exercise using 2-D strain deformation imaging.

Methods

Elite adolescent male football players (n = 42) completed simultaneous cardiopulmonary exercise testing (CPET) and exercise echocardiography measurement of LV myocardial deformation by 2-D strain imaging. LV longitudinal and circumferential 2-D strain and strain rates were analyzed at each stage during incremental exercise to a work rate of 150 W. Additionally, exercise LV myocardial deformation and its relation to metabolic exercise parameters were evaluated at each exercise stage and in recovery using repeated measures ANOVA, linear regression and paired t tests.

Results

LV peak systolic baseline 2-D strain (longitudinal: − 15.4 ± 2.5%, circumferential: − 22.5 ± 3.1%) increased with each exercise stage, but longitudinal strain plateaued at 50 W (mean strain reserve − 7.8 ± 3.0) and did not significantly increase compared to subsequent exercise stages (P > 0.05), whilst circumferential strain (mean strain reserve − 11.6 ± 3.3) significantly increased (P < 0.05) throughout exercise up to 150 W as the dominant mechanism of exercise LV contractility increase. Regression analyses showed LV myocardial strain increased linearly relative to HR, VO₂ and O₂ pulse (P < 0.05) for circumferential deformation, but showed attenuation for longitudinal deformation.

Conclusion

This study describes LV myocardial deformation dynamics by 2-D strain and provides reference values for LV myocardial strain and strain rate during exercise in adolescent footballers. It found important differences between LV longitudinal and circumferential myocardial mechanics during exercise and introduces a methodology that can be used to quantify LV function and cardiac reserve during exercise in adolescent athletes.

Epidemiology of the inherited cardiomyopathies

In the absence of contemporary, population-based epidemiological studies, estimates of the incidence and prevalence of the inherited cardiomyopathies have been derived from screening studies, most often of young adult populations, to assess cardiovascular risk or to detect the presence of disease in athletes or military recruits. The global estimates for hypertrophic cardiomyopathy (1/500 individuals), dilated cardiomyopathy (1/250) and arrhythmogenic right ventricular cardiomyopathy (1/5,000) are probably conservative given that only individuals who fulfil diagnostic criteria would have been included. This caveat is highly relevant because a substantial minority or even a majority of individuals who carry disease-causing genetic variants and are at risk of disease complications have incomplete and/or late-onset disease expression. The genetic literature on cardiomyopathy, which is often focused on the identification of genetic variants, has been biased in favour of pedigrees with higher penetrance. In clinical practice, an abnormal electrocardiogram with normal or non-diagnostic imaging results is a common finding for the sarcomere variants that cause hypertrophic cardiomyopathy, the titin and sarcomere variants that cause dilated cardiomyopathy and the desmosomal variants that cause either arrhythmogenic right ventricular cardiomyopathy or dilated cardiomyopathy. Therefore, defining the genetic epidemiology is also challenging given the overlapping phenotypes, incomplete and age-related expression, and highly variable penetrance even within individual families carrying the same genetic variant.

The Changes of Heart miR-1 and miR-133 Expressions following Physiological Hypertrophy Due to Endurance Training

Objective

MicroRNAs (miRNAs) play a key role in the development of the heart. Recent studies have shown that miR- 1 and miR-133 are key regulators of cardiac hypertrophy. Therefore, we aimed to evaluate the effect of an endurance training (ET) program on the expressions of these miRNAs and their transcriptional network.

Materials and Methods

In this experimental study, cardiac hypertrophy was induced by 14 weeks of ET for 1 hour per day, 6 days per week at 75% VO2 max). The rats (221 ± 23 g) in the experimental (n=7) and control (n=7) groups were anesthetized to evaluate heart morphology changes by echocardiography. Next, we evaluated expressions of miR-1 and miR-133, and heart and neural crest derivatives express 2 (Hand2), Mef2c, histone deacetylase 4 (Hdac4) and serum response factor (Srf) gene expressions by real-time polymerase chain reaction (PCR). Finally, the collected data were evaluated by the independent t test to determine differences between the groups

Results

The echocardiography result confirmed physiological hypertrophy in the experimental group that underwent ET as shown by the increased left ventricular weight/body surface area (LVW/BSA) (P=0.004), LVW/body weight (BW) (P=0.011), left ventricular diameter end-diastolic (LVDd) (P=0.003), and improvements in heart functional indexes such as fractional shortness (FS) (P=0.036) and stroke volume (SV) (P=0.002). There were significant increases in the expressions of miR-1 (P=0.001) and miR-133 (P=0.004). The expressions of Srf, Hdac4, and Hand2 genes significantly increased (P<0.001) in the experimental group Compared with the control group. The expression of Mef2c did not significantly change.

Conclusion

The expressions of miR-1 and miR-133 and their target genes appeared to be involved in physiological hypertrophy induced by ET in these rats.

Left ventricular mass normalization in child and adolescent athletes must account for sex differences

Background

To assess left ventricular hypertrophy, actual left ventricular mass (LVM) normalized for body size has to be compared to the LVM normative data. However, only some published normative echocardiographic data have been produced separately for girls and boys; numerous normative data for the pediatric population are not sex-specific. Thus, this study aimed to assess whether the LVM normative data should be developed separately for girls and boys practicing sports.

Methods

Left ventricular mass was computed for 331 girls and 490 boys, 5–19 years old, based on echocardiography. The effect of sex on the relationship between LVM and body size was evaluated using a linear regression model. Seven sets of the LVM normative data were developed, using different methodologies, to test concordance between sex-specific and non-specific normative data. Every set consisted of normative data that was sex-specific and non-specific. Upon these normative data, for every study participant, seven pairs of LVM z-scores were calculated based on her/his actual LVM. Each pair consisted of z-scores computed based on sex-specific and non-specific normative data from the same set.

Results

The regression lines fitted to the data points corresponding to LVM of boys had a higher slope than of girls, indicating that sex affects the relationship between LVM and body size. The mean differences between the paired LVM z-scores differed significantly from 0. The percentage of discordant indications, depending on the normalization method, ranged from 66.7% to 100% in girls and from 35.4% to 50% in boys. Application of the LVM normative data that were not sex-specific made relative LVM underestimated in girls and overestimated in boys.

Conclusion

The LVM normative data should be developed separately for girls and boys practicing sports. Application of normative data that are not sex-specific results in an underestimation of relative LVM in girls and overestimation in boys.

Revisiting the relationship between left ventricular ejection fraction and ventricular-arterial coupling

The aim of this article was to analyse in‐depth the relationship between left ventricular (LV) ejection fraction (EF) (LVEF) and the most commonly used formulas for the calculation of LV elastance (Ees), volume intercept at 0 mmHg pressure (V0), effective arterial elastance (Ea), and ventricular–arterial coupling (VAC) as are validated today. We analyse the mathematical resulting consequences, raising the question on the physiological validity. To our knowledge, some of the following mathematical consequences have never been published. On the basis of studies demonstrating that normal LV dimensions and LVEF have a Gaussian unimodal distribution, we considered that the normal modal LVEF is 62% or very close to it. Expressed as a fraction, it is 0.62, that is, the reciprocal of the Phi number (namely, 1/Φ ~ 0.618). Applying Euclid's mathematical law on the extreme and mean ratio (the golden ratio), we studied the LVEF–VAC relationship in normal hearts. The simplification of the VAC formula (with V0 = 0) leads to false physiological results; V0 extraction from single‐beat Chen's formula leads to high negative results in normal subjects; based on the Euclid law, LVEF and Ea/Ees will be equal for a ratio value of 0.618 (62%) where V0 cannot be different from 0 mL; LVEF and VAC inverse relationship formula (Ea/Ees = 1/LVEF − 1) is reducible to a fundamental property of Phi: 1/Φ = (Φ − 1), being valid only if LVEF = VAC at a 0.618 value; according to this restriction, Vo can only be 0 mL, thus describing a very limited range. The Ea/Ees ratio, owing to its mathematical more dynamic behaviour, can be more sensitive than LVEF, being a valuable clinical tool in patients with heart failure (HF) with reduced EF, acute unstable haemodynamic situations, where Ees and Ea variations are disproportionate. However, the application is doubtful in HF with preserved EF where Ees and Ea may have same‐direction augmentation. The modified VAC formula suffers from oversimplification, reducing it to a dimensionless ratio, which is supposed to approximate non‐linear time‐varying functions. Thus, we advocate for caution and in‐depth understanding when using simplified formulas in clinical practice.

The adolescent athlete's heart; A miniature adult or grown-up child?

The systematic development of early age talent in sports academies has led to the professionalization of pediatric sport and the sports physician need to be aware of pediatric cardiological problems. Research into the medical cardiac care and assessment of the pediatric athlete are accumulating, but specific pediatric international guidelines are not available yet and reference data for ECG and echocardiography are incomplete, in particular for the age group <12 years of age. This article is an introduction to the physiological and diagnostics specifics of the pediatric athlete. The focus lies in the differences in presentation and diagnosis between pediatric and adult athletes for the most common pathologies. Reference data for electrical and structural adaptations to intensive exercise are sparse particularly in athletes aged below 12 years old. Training related changes include decrease of resting heart rate, increase of cardiac output, ventricular cavity size, and wall thickness. Cardiac hypertrophy is less pronounced in pediatric athletes, as HR mediated cardiac output increase to endurance exercise is the dominant mechanism in peripubertal children. As in adults, the most pronounced cardiovascular adaptations appear in classical endurance sports like rowing, triathlon, and swimming, but the specifics of pediatric ECG and echocardiographic changes need to be considered.

Gender Differences in Hemodynamic Regulation and Cardiovascular Adaptations to Dynamic Exercise

Exercise is a major challenge for cardiovascular apparatus since it recruits chronotropic, inotropic, pre-load, and afterload reserves. Regular physical training induces several physiological adaptations leading to an increase in both cardiac volume and mass. It appears that several gender-related physiological and morphological differences exist in the cardiovascular adjustments and adaptations to dynamic exercise in humans. In this respect, gender may be important in determining these adjustments and adaptations to dynamic exercise due to genetic, endocrine, and body composition differences between sexes. Females seem to have a reduced vasoconstriction and a lower vascular resistance in comparison to males, especially after exercise. Significant differences exist also in the cardiovascular adaptations to physical training, with trained women showing smaller cardiac volume and wall thickness compared with male athletes. In this review, we summarize these differences.

The Assessment of the Paediatric Athlete

The success of systematic early age talent development has led to the professionalisation of youth sports academies used by clubs and governing bodies alike, and sports physicians are nowadays commonly confronted with paediatric cardiological problems. Medical cardiac care of the paediatric athlete is however in its infancy, and the international guidelines that are present for adult athletes, are not yet available. Similarly, reference data for ECG and echocardiography are incomplete. The aim of this article is to provide and introduction to the cardiac care of the paediatric athlete to facilitate healthy and above all, safe talent development, but also provide guidance on how to distinguish adaptive, beneficial cardiovascular remodelling from underlying pathology of congenital or inherited cardiovascular disease. Differences in presentation, diagnosis and treatment between childhood and adult athletes are highlighted and can educate the reader in the emerging field of paediatric sports cardiology.

Recommendations for exercise and screening for safe athletic participation in hypertensive youth

Physical activity is an important component of ideal cardiovascular health. Current guidelines recommend that youth with hypertension participate in competitive sports once hypertensive target organ effects and risks have been assessed and that children with hypertension receive treatment to lower BP below stage 2 thresholds (e.g., < 140/90 mmHg or < 95th percentile + 12 mmHg) before participating in competitive sports. Despite these recommendations, pediatricians and pediatric subspecialists continue to struggle with how best to counsel their patients regarding appropriate forms of physical activity, the impact of exercise on blood pressure, and how best to screen for cardiovascular conditions that place youth at risk for sudden cardiac death. This review provides a summary of our current knowledge regarding the safety and utility of exercise in the management of high blood pressure in youth. We review determinants of blood pressure during exercise, the impact of blood pressure on cardiovascular health and structure, mechanisms for assessing cardiometabolic fitness (e.g., exercise stress test), contraindications to athletic participation, and how best to plan for athletic participation among hypertensive youth. Greater knowledge in these areas may offer clarity to providers faced with the challenge of prescribing exercise recommendations for hypertensive youth.

Scaling left ventricular mass in adolescent female soccer players

BACKGROUND

The aim of the study was to examine the contribution of chronological age (CA), skeletal maturation, training experience and concurrent body size descriptors, to inter-individual variance in left ventricular mass (LVM) among female adolescent soccer players.

METHODS

The sample included 228 female soccer players 11.8-17.1 years. Training experience defined as years of participation in competitive soccer (range 2-9 years), was obtained by interview. Stature, body mass and skinfolds (triceps, medial calf) were measured. Fat mass was estimated; Fat-free mass was derived. LVM was assessed by echocardiography. Skeletal maturity status was as the difference of skeletal age (SA, Fels method) minus CA.

RESULTS

Fat-free mass was the most prominent single predictor of LVM (R2 = 36.6%). It was associated with an allometric coefficient close to linearity (k = 0.924, 95%CI: 0.737 to 1.112). A significant multiplicative allometric model including body mass, fat-free mass, CA, training experience and skeletal maturity status was also obtained (R = 0.684; R2 = 46.2%).

CONCLUSION

Stature has limitations as a valid size descriptor of LVM. Body mass, fat-free mass, training experience, CA, body mass and skeletal maturity status were relevant factors contributing to inter-individual variability in LVM.

Impact of connective tissue dysplasia on heart adaptation to exercise stress in young athletes

This study addresses the contribution of connective tissue dysplasia (CTD) to the cardiac function in young athletes. Thirty-three cross-country skiers aged 15 underwent maximum stress-ECG and TTE before and immediately after stress-test. Global and regional function of LV was evaluated with the use of further image processing. We found that 87.9 % of athletes had phenotypic markers of CTD ranged from 12 to 26 score points. Parameters of LV global function at rest in all studied athletes corresponded to normal age-gender values but markers of regional function showed high degree of mechanical asynchrony that depended on extent of CTD. All athletes passed stress-test successfully and demonstrated a high level of exercise performance. Meanwhile, the variables of LV pump-function and mechanical asynchrony close correlated with CTD extent. Obtained results imply that the increase of CTD extent was accompanied by the decrease of scale of heart adaptation to physical loads.

Left ventricular mass normalization for body size in children based on an allometrically adjusted ratio is as accurate as normalization based on the centile curves method

BACKGROUND

Normalization for body size is required for reliable left ventricular mass (LVM) evaluation, especially in children due to the large variability of body size. In clinical practice, the allometrically adjusted ratio of LVM to height raised to the power of 2.7 is often used. However, studies presenting normative LVM data for children recommend centile curves as optimal for the development of normative data. This study aimed to assess whether the allometrically adjusted LVM-to-height ratio can reliably reproduce the results of LVM normalization for height based on the centile curves method.

METHODS

Left ventricular mass was computed for 464 boys and 327 girls, 5-18 years old, based on echocardiographic examination. Normalized data representing LVM for height were developed using the centile curves construction method and two variants of the allometrically adjusted ratio method: one variant with the allometric exponents specific to the study groups, and one variant with the universal exponent of 2.7. The agreement between the allometric methods and the centile curves method was analyzed using the concordance correlation coefficient, sensitivity, and specificity.

RESULTS

For both the specific allometric variant and the universal variant, the analysis of concordance has indicated high reproducibility compared to the centile curves method. The respective coefficient values were 0.9917 and 0.9916 for girls, and 0.9886 and 0.9869 for boys. The sensitivity and specificity test has also shown high agreement. However, for girls, the sensitivity was higher for the specific variant (100% vs. 90.9%).

CONCLUSION

The results of the study show that allometric scaling of LVM for height can very reliably reproduce the results of LVM normalization for height based on the centile curves method. However, the analysis of sensitivity and specificity indicates greater agreement for the allometric normalization with the group-specific allometric exponents.

Influence of Vigorous Physical Activity on Structure and Function of the Cardiovascular System in Young Athletes-The MuCAYA-Study

Objective: Moderate physical activity (PA) is associated with a reduced risk to develop cardiovascular disease. However, junior athletes exercise between 10 and 20 h a week with intensities exceeding moderate levels by far. In this regard, the cardiovascular system has to increase its work five to six times compared to moderate intensities. This may result in potentially pathological adaptations of the cardiovascular system. The underlying process of vascular adaptations to exercise is yet not fully understood and hardly investigated in junior athletes. An increased blood pressure and pulse wave velocity, ventricular hypertrophy, arrhythmia, and even sudden cardiac death (SCD) has been reported in adult athletes. Studies, examining the cardiovascular system in children, its association to intensity and type of exercise, are rare. Therefore, we present the study protocol of a prospective cross-sectional study that investigates the influence of PA on the cardiovascular system in young athletes.

Methods and Design: Children and adolescents, 7–18 years, presenting for their annual pre-participation screening at the Institute of Preventive Pediatrics, Faculty of Sports and Health Sciences, Technical University of Munich (TUM), are examined in this prospective cross-sectional study. Vascular parameters measured by ultrasound are carotid intima-media thickness (cIMT), vascular stiffness (AC, Ep, β, PWV β), and the vascular diameter (D) to calculate the IMT:Diameter-Ratio (IDR). Cardiac function is evaluated by a 12-lead ECG, and echocardiographic parameters (end-diastolic left ventricular diameter, left ventricular diastolic posterior wall thickness, diastolic septal thickness, left ventricular mass and relative wall thickness, ejection fraction, and shortening fraction). A cardiopulmonary exercise test is performed on a bicycle ergometer, muscular strength is assessed with the handgrip test, and physical activity with the MoMo questionnaire.

Discussion: It is essential to follow young athletes over the course of their career in order to detect pathophysiological changes in the myocardium as soon as possible. If these changes are preceded or followed by changes in vascular structure and function is not known yet. Therefore, we present the study protocol of the Munich Cardiovascular adaptations in young athletes study (MuCAYA-Study) which investigates the association between vascular and cardiac adaptation to intensive exercise in junior athletes.

Accuracy of the 2017 international recommendations for clinicians who interpret adolescent athletes’ ECGs: a cohort study of 11 168 British white and black soccer players

Aim

To investigate the accuracy of the recently published international recommendations for ECG interpretation in young athletes in a large cohort of white and black adolescent soccer players.

Methods

11 168 soccer players (mean age 16.4±1.2 years) were evaluated with a health questionnaire, ECG and echocardiogram; 10 581 (95%) of the players were male and 10 163 (91%) were white. ECGs were retrospectively analysed according to (1) the 2010 European Society of Cardiology (ESC) recommendations, (2) Seattle criteria, (3) refined criteria and (4) the international recommendations for ECG interpretation in young athletes.

Results

The ESC recommendations resulted in a higher number of abnormal ECGs compared with the Seattle, refined and international criteria (13.2%, 4.3%, 2.9% and 1.8%, respectively). All four criteria were associated with a higher prevalence of abnormal ECGs in black athletes compared with white athletes (ESC: 16.2% vs 12.9%; Seattle: 5.9% vs 4.2%; refined: 3.8% vs 2.8%; international 3.6% vs 1.6%; p<0.001 each). Compared with ESC recommendations, the Seattle, refined and international criteria identified a lower number of abnormal ECGs—by 67%, 78% and 86%, respectively. All four criteria identified 36 (86%) of 42 athletes with serious cardiac pathology. Compared with ESC recommendations, the Seattle criteria improved specificity from 87% to 96% in white athletes and 84% to 94% in black athletes. The international recommendations demonstrated the highest specificity for white (99%) and black (97%) athletes and a sensitivity of 86%.

Conclusions

The 2017 international recommendations for ECG interpretation in young athletes can be applied to adolescent athletes to detect serious cardiac disease. These recommendations perform more effectively than previous ECG criteria in both white and black adolescent soccer players.

Normal basic 2D echocardiographic values to screen and follow up the athlete's heart from juniors to adults: What is known and what is missing. A critical review

In the last few years, multiple echocardiographic nomograms have been published. However, normal values calculated in the general population are not applicable to athletes, whose hearts may be enlarged and hypercontractile. Accordingly, athletes require specific nomograms. Our aim is to provide a critical review of echocardiographic nomograms on two-dimensional (2D) measures for athletes. We performed a systematic search in the National Library of Medicine for Medical Subject Headings and free text terms including echocardiography, athletes, normal values and nomograms. The search was refined by adding the keywords heart, sport, elite, master, children and young. Twenty-eight studies were selected for the final analysis. Our research revealed that currently available ranges of normality for athletes reported by different authors are quite consistent, with limited exceptions (e.g. atria, aorta). Numerical and methodological limitations, however, emerged. Numerical limitations included a limited sample size (e.g. < 450 subjects) of the population assessed and the paucity of data in women, non-Caucasian athletes, and junior and master athletes. Some data on M-mode measurements are available, while those for some specific structures (e.g. left atrial (LA) area and volumes, right ventricular diameters and aorta) are limited or rare (e.g. LA area). There was heterogeneity in data normalization (by gender, sport type and ethnicity) and their expression was limited to mean values (Z-scores have rarely been employed), while variability analysis was often lacking or incomplete. We conclude that comprehensive nomograms using an appropriate sample size, evaluating a complete dataset of 2D (and three-dimensional) measures and built using a rigorous statistical approach are warranted.