The upper limit of physiological cardiac hypertrophy in elite male and female athletes: the British experience

Relation between cardiac dimensions and peak oxygen uptake

BACKGROUND

Long term endurance training is known to increase peak oxygen uptake (VO2peak) and induce morphological changes of the heart such as increased left ventricular mass (LVM). However, the relationship between and the total heart volume (THV), considering both the left and right ventricular dimensions in both males and females, is not completely described. Therefore, the aim of this study was to test the hypothesis that THV is an independent predictor of VO2peak and to determine if the left and right ventricles enlarge in the same order of magnitude in males and females with a presumed wide range of THV.

METHODS AND RESULTS

The study population consisted of 131 subjects of whom 71 were athletes (30 female) and 60 healthy controls (20 female). All subjects underwent cardiovascular MR and maximal incremental exercise test. Total heart volume, LVM and left- and right ventricular end-diastolic volumes (LVEDV, RVEDV) were calculated from short-axis images. was significantly correlated to THV, LVM, LVEDV and RVEDV in both males and females. Multivariable analysis showed that THV was a strong, independent predictor of (R2 = 0.74, p < 0.001). As LVEDV increased, RVEDV increased in the same order of magnitude in both males and females (R2 = 0.87, p < 0.001).

CONCLUSION

Total heart volume is a strong, independent predictor of maximal work capacity for both males and females. Long term endurance training is associated with a physiologically enlarged heart with a balance between the left and right ventricular dimensions in both genders.

The "Athlete's Heart": relation to gender and race

Long-term athletic training is associated with changes in cardiac morphology, commonly described as "athlete's heart." Although numerous studies have investigated the effects of training on cardiac dimensions, most are limited to male Caucasian athletes, and few data are available regarding the effect of long-term exercise training on the woman's heart. This article reviews the athlete's heart in relation to gender and race.

Echocardiographic characteristics of professional tennis players at the Roland Garros French Open

BACKGROUND

Intensive sport may induce cardiac modifications. No recent study has been performed in elite tennis players. The aim of this cross-sectional study was to analyze the cardiac characteristics in a population of professional tennis players.

METHODS

During the 2004 French Open Tennis Tournament, we offered complete echocardiographic screening to all professional tennis players. The study population consisted of 160 subjects: 80 tennis players (50 men and 30 women) and age- and sex-matched control groups (n = 80).

RESULTS

Indexed left ventricular mass was significantly higher in tennis players (P < .0001). Left ventricular hypertrophy was present in 18 male (36%) and 6 female (20%) tennis players versus 2 men (4%) and no woman in the control groups (P < .0001 and P = .02, respectively). All indexed right and left atrial measurements were significantly higher in tennis players (P < .003). The incidence of left and right atrial dilation was significantly higher in tennis players (P < or = .0001). Indexed right atrial area and left atrial volume were significantly higher in baseline players as compared with offensive players and to control groups (P < .0001), whereas there was no significant difference in left ventricular mass according to the style of play (P > .75). No significant between-group difference was observed in Doppler data.

CONCLUSIONS

In the present study, professional tennis players presented significant cardiac differences, as compared to a control group, with moderate left ventricular hypertrophy, bilateral atrial dilation, and normal systolic and diastolic functions. Atrial dilation is related to the style of play (baseline or offensive) and should be considered as physiological in tennis players.

Echocardiographic characterisation of left ventricular geometry of professional male tennis players

BACKGROUND

The cardiac characteristics of various types of athletes have been defined by echocardiography. Athletes involved in predominately static exercise, such as bodybuilders, have been found to have more concentric hypertrophy, whereas those involved in dynamic exercise, such as long distance runners, have more eccentric hypertrophy. Tennis at the elite level is a sport that is a combination of static and dynamic exercise.

OBJECTIVE

To characterise left ventricular geometry including left ventricular hypertrophy by echocardiography in male professional tennis players.

DESIGN

Retrospective study of screening echocardiograms that were performed on male professional tennis players.

SETTING

All echocardiograms were performed at the Mayo Clinic (Jacksonville, Florida, USA) between 1998-2000.

PARTICIPANTS

A total of 41 male professional tennis players, with a mean age of 23.

RESULTS

Left ventricular hypertrophy was present in 30 of 41 subjects (73%, 95% CI: 57%-86%). The majority of players manifested eccentric hypertrophy (n = 22, 54%). Concentric hypertrophy (n = 9, 22%) and normal geometry (n = 7, 17%) were encountered with similar frequency. Only 7% (n = 3) manifested concentric remodelling. The mean thickness of both the interventricular septum and the posterior wall was 11.0 mm. The mean LVEDd was 55 mm. The mean RWT was 0.41. The mean LVMI was 130 gm/m2 and the mean EF was 64%. Five of the 41 subjects had an abnormal septal thickness of 13 mm.

CONCLUSION

This was the first study to specifically describe the full range of echocardiographically-determined left ventricular geometry in professional male tennis players. The majority of subjects exhibited abnormal geometry, predominantly eccentric hypertrophy.

Health benefits of tennis

The aim of the study was to explore the role of tennis in the promotion of health and prevention of disease. The focus was on risk factors and diseases related to a sedentary lifestyle, including low fitness levels, obesity, hyperlipidaemia, hypertension, diabetes mellitus, cardiovascular disease, and osteoporosis. A literature search was undertaken to retrieve relevant articles. Structured computer searches of PubMed, Embase, and CINAHL were undertaken, along with hand searching of key journals and reference lists to locate relevant studies published up to March 2007. These had to be cohort studies (of either cross sectional or longitudinal design), case-control studies, or experimental studies. Twenty four studies were identified that dealt with physical fitness of tennis players, including 17 on intensity of play and 16 on maximum oxygen uptake; 17 investigated the relation between tennis and (risk factors for) cardiovascular disease; and 22 examined the effect of tennis on bone health. People who choose to play tennis appear to have significant health benefits, including improved aerobic fitness, a lower body fat percentage, a more favourable lipid profile, reduced risk for developing cardiovascular disease, and improved bone health.

Development of structural cardiac adaptation in basketball players

BACKGROUND

As specific features of the basketball player's myocardial structure and function are still rather poorly investigated, we aimed at comparing left ventricular (LV) echocardiographic indices in players of different age groups.

METHODS

Male basketball players aged 8-13 years (n=31), 14-17 years (n=31) and 18-28 years (n=31) were examined using standard echocardiography. End-diastolic LV posterior wall thickness and internal diameter, as well as interventricular septum thickness, were measured by M-mode. Relative wall thickness was calculated by dividing the sum of the thicknesses of the interventricular septum and LV posterior wall by LV internal diameter. LV mass and ejection fraction were also calculated. The morphological LV parameters were corrected for body surface area. The peak early (E) and peak late (A) transmitral flow velocities were measured using pulsed Doppler, and the ratio (E/A) was calculated.

RESULTS

Significant differences in the absolute internal LV diameter among the age groups disappeared after allometric scaling. However, relative wall thickness as well as body size indexed LV posterior wall thickness and LV mass were significantly greater in the adolescents and adults than in the children. Players of different age groups did not differ in the E/A ratio, while ejection fraction was elevated in adolescents.

CONCLUSIONS

Regular basketball training results in moderate cardiac hypertrophy in adolescents and adult athletes due to thickening of myocardial walls.

The early repolarization variant—normal or a marker of heart disease in certain subjects

The theory is advanced that the early repolarization variant may not always be benign and that it can become a substrate for ventricular arrhythmias, sudden death, and hypercontractility cardiomyopathy in some subjects, including certain high-performance athletes. In addition, it is suggested that it likely represents part of a spectrum of cardiovascular anomalies related to nonischemic ST elevation including Brugada syndrome, and that it may also have a molecular genetic origin of variable penetrance.

Echocardiographic measures of diastolic function in pediatric heart disease

PURPOSE OF REVIEW

The past year has seen a continued evolution in the echocardiographic assessment of diastolic function in children. This paper reviews published studies from the past year that have helped characterize diastolic function using echocardiography in children.

RECENT FINDINGS

Characterization of diastolic function using Doppler and Doppler tissue imaging in the normal infant and child was a primary focus of pediatric echocardiographic investigation. These technologies appear to hold significant promise as tools to improve understanding of diastolic function in the normal child as the heart matures. Diastolic function in children with congenital heart disease has also been better characterized using these tools, specifically in patients with atrial septal defects, tetralogy of Fallot, single ventricle physiology, and following cardiac transplantation. Finally, diastolic function in acquired heart disease or with systemic disease in the child has been evaluated using echocardiography, with recent reports describing findings in children with dilated cardiomyopathy, chronic renal disease, obesity, type I diabetes, juvenile rheumatoid arthritis, obstructive sleep apnea, and after anthracycline exposure for childhood cancer.

SUMMARY

Pediatric echocardiography has clearly become the primary tool for describing and characterizing diastolic function in infants and children both with and without heart disease. It is becoming an important noninvasive diastolic monitoring tool that allows serial assessment of pathologic diastolic disease in both primary myocardial and systemic disease states.

Bicuspid aortic valve

Two competitive soccer players aged 23 and 17 years with known bicuspid aortic valve presented for sports-medical pre-participation screening. Both athletes were well trained and had a maximal oxygen uptake of 61 and 60 ml/min/kg, respectively. Echocardiography of the first athlete revealed an eccentric hypertrophy of the left ventricle (end-diastolic diameter 58-59 mm, septal and posterior myocardial wall thickness 12-13 mm) with good systolic and diastolic function and a functional bicuspid aortic valve with mild regurgitation. In the second athlete, echocardiography showed a bicuspid aortic valve with moderate regurgitation and a relative stenosis, a hypertrophied left ventricle (end-diastolic diameter 62-63 mm, myocardial wall thickness 13-16 mm) and dilation of the ascending aorta of 46 mm, which was confirmed by magnetic resonance imaging. According to international guidelines, the first athlete was allowed to participate in competitive soccer. Nevertheless, regular cardiologic examinations in intervals of 6 months were recommended. In the second case, the athlete was not allowed to take part in competitive sports due to the extended ecstasy of the ascending aorta and the concomitant risk of an aortic rupture. In addition, the left ventricular hypertrophy has to be considered as pathologic. Therefore, the athlete was only allowed to exercise in recreational sports with low and easily controllable intensities.

CONCLUSION

In athletes with bicuspid aortic valve, besides the evaluation of the aortic valve, physiologic adaptations of the heart have to be differentiated from pathological changes. Furthermore, the aorta deserves special attention, because in the case of a (probably genetically determined) dilated ascending aorta, an elevated risk for aortic rupture is present during intensive and competitive exercise. A general judgement in athletes with bicuspid aortic valves on their ability to participate in competitive sports is, therefore, not possible.

Sex-specific characteristics of cardiac function, geometry, and mass in young adult elite athletes

PURPOSE

To study young adult elite athletes with age- and sex-matched sedentary controls to assess sex-specific differences for left ventricular (LV) and right ventricular (RV) volumes and mass as well as for LV contraction and relaxation.

MATERIALS AND METHODS

A total of 23 male athletes (mean age 25 +/- 4 years, training 22 +/- 7 hours/week in rowing, swimming, or triathlon) and 20 female athletes (mean age 24 +/- 4 years, training 19 +/- 5 hours/week in rowing, swimming, or triathlon) and age- and sex-matched sedentary controls (21 male/17 female) underwent cardiovascular magnetic resonance (CMR) imaging (1.5 Tesla). Cardiac phase contrast imaging using a black-blood k-space segmented gradient echo sequence was used for analysis of cardiac contraction and relaxation and steady-state free-precession cine images were acquired for determination of cardiac volumes and mass.

RESULTS

Male and female athletes showed similar increases in LV and RV volume and mass indices when compared to controls (ranging between 15% and 42%). No sex-specific differences in training effect on LV and RV volumes, mass indices, and ejection fractions, as well as LV to RV ratios of these volume and mass indices (parameters of balanced LV and RV dilatation and hypertrophy) were observed (all P for interaction >0.05). Similarly, no sex-specific differences in training effect on cardiac contraction and relaxation were found (all P for interaction >0.05).

CONCLUSION

Young adult elite athletes do not show sex-specific adaptive structural and functional changes to exercise training in accordance with the benign nature of the hypertrophy associated with athlete's heart.

Adaptation of left ventricular morphology to long−term training in sprint− and endurance−trained elite runners

Long-term studies on left ventricular (LV) adaptation have not been reported. The echocardiograms of 41 top-class runners (8 males and 6 females sprint-trained, 15 males and 12 females endurance-trained) were recorded at the beginning and after 1, 2, and 3 years of training. A one-way ANOVA and a linear regression analysis were conducted to determine changes and association between performance and LV values. Training resulted in an increase in performance and LV internal diameter at end-diastole (LVIDd) and decreases in end-diastolic interventricular septal wall thickness, and posterior wall thickness (PWTd). There were no significant differences in LV mass and LV ejection fraction (LVEF, %). The changes in PWTd were linked to enlargement of the LV. In athletes with unusual LV dilatation (>60 mm), LVIDd was related to performance and LVEF was >50%. Maximal wall thickness was <13 mm in all athletes. LV adaptations were independent of sex and type of training and related to the initial level of performance. We believe that LV enlargement in elite runners is a physiological adaptation and that the LVIDd is a predictor of running performance.

Echocardiography to Measure Fitness of Elite Runners

We evaluated the echocardiograms of 134 male and 54 female elite runners who competed over different distances to observe cardiac enlargement and differences among athletes engaged in different types of training, and to relate the echographic dimension with running performance. In male runners, left ventricular (LV) internal diameter at end diastole (LVIDd), LV mass, and left atrial diameter were increased by the length of distance ( P < .001) whereas right ventricular diameter was increased only in marathon runners. In female runners, this association was found when LVIDd, LV mass, and left atrial diameter were adjusted for body surface area ( P < .001). Wall thickness was not related to distance running. Abnormal LV dilation was associated with a low LV ejection fraction for the higher values of LVIDd, but not for the higher indexed LVIDd values. In male runners, LVIDd was associated with 100 m ( r = -0.67, P < .01), 10,000 m ( r = -0.70, P < .001), and marathon ( r = -0.54, P < .001) and in female runners with a 400-m ( r = -0.84, P < .001) race time. These results show that sprint- and endurance-trained runners had an eccentric hypertrophy and that it is necessary to establish a new upper limit of abnormal cavity dilatation as indexed LVIDd. The normal systolic function and the relationship between LVIDd and performance indicate that LV enlargement in elite runners is a physiologic adaptation and that echocardiographic assessment can be used to determine the fitness of runners.