Left ventricular diastolic function in elite athletes with physiologic cardiac hypertrophy

Machine Learning for Electrocardiographic Features to Identify Left Atrial Enlargement in Young Adults: CHIEF Heart Study

Background

Left atrial enlargement (LAE) is associated with cardiovascular events. Machine learning for ECG parameters to predict LAE has been performed in middle- and old-aged individuals but has not been performed in young adults.

Methods

In a sample of 2,206 male adults aged 17–43 years, three machine learning classifiers, multilayer perceptron (MLP), logistic regression (LR), and support vector machine (SVM) for 26 ECG features with or without 6 biological features (age, body height, body weight, waist circumference, and systolic and diastolic blood pressure) were compared with the P wave duration of lead II, the traditional ECG criterion for LAE. The definition of LAE is based on an echocardiographic left atrial dimension > 4 cm in the parasternal long axis window.

Results

The greatest area under the receiver operating characteristic curve is present in machine learning of the SVM for ECG only (77.87%) and of the MLP for all biological and ECG features (81.01%), both of which are superior to the P wave duration (62.19%). If the sensitivity is fixed to 70–75%, the specificity of the SVM for ECG only is up to 72.4%, and that of the MLP for all biological and ECG features is increased to 81.1%, both of which are higher than 48.8% by the P wave duration.

Conclusions

This study suggests that machine learning is a reliable method for ECG and biological features to predict LAE in young adults. The proposed MLP, LR, and SVM methods provide early detection of LAE in young adults and are helpful to take preventive action on cardiovascular diseases.

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.

Athlete's Heart in Asian Military Males: The CHIEF Heart Study

Background: Elite athlete's heart is characterized by a greater left ventricular mass indexed by body surface area (LVMI) and diastolic function; however previous studies are mainly conducted in non-Asian athletes compared to sedentary controls.

Methods: This study included 1,388 male adults, aged 18–34 years, enrolled in the same unified 6-month physical training program in Taiwan. During the midterm exams of 2020, all trainees completed a 3-km run (endurance) test, and 577 were randomly selected to attend a 2-min push-up (muscular strength) test. Elite athletes were defined as the performance of each exercise falling one standard deviation above the mean (16%). Cardiac structure and function were measured by echocardiography and compared between elite and non-elite athletes. Multiple logistic regression analysis was used to determine the independent predictors of elite athlete status at each exercise modality.

Results: As compared to non-elite controls, elite endurance athletes had greater LVMI (84.4 ± 13.6 vs. 80.5 ± 12.9 g/m², p < 0.001) and lateral mitral E'/A' ratio (2.37 ± 0.73 vs. 2.22 ± 0.76, p < 0.01) with lower late diastolic A' (7.77 ± 2.16 vs. 8.30 ± 3.69 cm/s, p = 0.03). Elite strength athletes had greater LVMI (81.8 ± 11.4 vs. 77.5 ± 12.1, p = 0.004) and lateral mitral E'/A' ratio (2.36 ± 0.70 vs. 2.11 ± 0.71, p < 0.01) with a greater early diastolic E' (19.30 ± 4.06 vs. 18.18 ± 4.05 cm/s, p = 0.02). Greater LVMI and lower heart rate were independent predictors of elite endurance athletes [odds ratio (OR) and 95% confidence intervals: 1.03 (1.02, 1.04) and 0.96 (0.95, 0.98), respectively]. Greater LVMI, lateral mitral E'/A' ratio and right ventricular systolic pressure were independent predictors of elite strength athletes [OR: 1.03 (1.01, 1.05), 1.50 (1.06, 2.12), and 1.12 (1.05, 1.19), respectively].

Conclusions: Cardiac structural and functional characteristics differ between endurance and strength elite athletes. While greater LVMI predicts elite status in both groups of Asian athletes, consistent with findings from Western elite athletes, greater diastolic function, and right ventricular systolic pressure characterize strength elite athletes, while lower heart rate at rest predicts endurance elite athletic status.

Characteristics of the athlete's heart in aged hypertensive and normotensive subjects

BACKGROUND

Both hypertension and age-related impairment of the cardiac condition are known to be improved by regular physical training. As relatively few studies have been reported about the older, hypertensive patients, the aim of this study was to establish cardiac benefits of active lifestyle in these subjects.

METHODS

Two-dimensionally guided M-mode, Doppler- and tissue Doppler echocardiography was performed in 199 normo- and hypertensive, active and sedentary older (age>60 yrs.) men (111) and women (88). Results were compared either by ANOVA, or by Kruskall-Wallis test.

RESULTS

The left ventricular muscle index (LVMI), which is higher in young active than in sedentary persons, proved to be smaller in the active than sedentary older subjects: men normotensives: actives 83 vs. sedentary ones 98, hypertensives: actives 88 vs. sedentary ones 107, women normotensives: actives 77 vs. sedentary ones 89 g/m3. Diastolic function was better in the active groups demonstrated both by the ratio of the early to atrial peak blood flow velocities (men: normotensives: actives 1.03 vs. sedentary ones 0.76, women normotensives: actives 1.21 vs. sedentary ones 0.9, hypertensives: actives 1.04 vs. sedentary ones 0.88). The tissue Doppler results were also better in the active groups; the difference between the active and sedentary groups was more marked in the normotensive male groups than in the hypertensive ones.

CONCLUSIONS

Active lifestyle prevents age-related pathological LV hypertrophy, and attenuates the LV diastolic dysfunction.

Complete Reversion of Cardiac Functional Adaptation Induced by Exercise Training

PURPOSE

Long-term exercise training is associated with characteristic cardiac adaptation, termed athlete's heart. Our research group previously characterized in vivo left ventricular (LV) function of exercise-induced cardiac hypertrophy in detail in a rat model; however, the effect of detraining on LV function is still unclear. We aimed at evaluating the reversibility of functional alterations of athlete's heart after detraining.

METHODS

Rats (n = 16) were divided into detrained exercised (DEx) and detrained control (DCo) groups. Trained rats swam 200 min·d for 12 wk, and control rats were taken into water for 5 min·d. After the training period, both groups remained sedentary for 8 wk. We performed echocardiography at weeks 12 and 20 to investigate the development and regression of exercise-induced structural changes. LV pressure-volume analysis was performed to calculate cardiac functional parameters. LV samples were harvested for histological examination.

RESULTS

Echocardiography showed robust LV hypertrophy after completing the training protocol (LV mass index = 2.61 ± 0.08 DEx vs 2.04 ± 0.04 g·kg DCo, P < 0.05). This adaptation regressed after detraining (LV mass index = 2.01 ± 0.03 vs 1.97 ± 0.05 g·kg, n.s.), which was confirmed by postmortem measured heart weight and histological morphometry. After the 8-wk-long detraining period, a regression of the previously described exercise-induced cardiac functional alterations was observed (DEx vs DCo): stroke volume (SV; 144.8 ± 9.0 vs 143.9 ± 9.6 μL, P = 0.949), active relaxation (τ = 11.5 ± 0.3 vs 11.3 ± 0.4 ms, P = 0.760), contractility (preload recruitable stroke work = 69.5 ± 2.7 vs 70.9 ± 2.4 mm Hg, P = 0.709), and mechanoenergetic (mechanical efficiency = 68.7 ± 1.2 vs 69.4 ± 1.8, P = 0.742) enhancement reverted completely to control values. Myocardial stiffness remained unchanged; moreover, no fibrosis was observed after the detraining period.

CONCLUSION

Functional consequences of exercise-induced physiological LV hypertrophy completely regressed after 8 wk of deconditioning.

Deaths in triathletes: immersion pulmonary oedema as a possible cause

BACKGROUND/AIM

To address the question as to whether immersion pulmonary oedema (IPO) may be a common cause of death in triathlons, markers of swimming-induced pulmonary oedema (SIPO) susceptibility were sought in triathletes' postmortem examinations.

METHODS

Deaths while training for or during triathlon events in the USA and Canada from October 2008 to November 2015 were identified, and postmortem reports requested. We assessed obvious causes of death; the prevalence of left ventricular hypertrophy (LVH); comparison with healthy triathletes.

RESULTS

We identified 58 deaths during the time period of the review, 42 (72.4%) of which occurred during a swim. Of these, 23 postmortem reports were obtained. Five individuals had significant (≥70%) coronary artery narrowing; one each had coronary stents; retroperitoneal haemorrhage; or aortic dissection. 9 of 20 (45%) with reported heart mass exceeded 95th centile values. LV free wall and septal thickness were reported in 14 and 9 cases, respectively; of these, 6 (42.9%) and 4 (44.4%) cases exceeded normal values. 6 of 15 individuals (40%) without an obvious cause of death had excessive heart mass. The proportion of individuals with LVH exceeded the prevalence in the general triathlete population.

CONCLUSIONS

LVH-a marker of SIPO susceptibility-was present in a greater than the expected proportion of triathletes who died during the swim portion. We propose that IPO may be a significant aetiology of death during the swimming phase in triathletes. The importance of testing for LVH in triathletes as a predictor of adverse outcomes should be explored further.

Myocardial hypertrophy and its role in heart failure with preserved ejection fraction

Left ventricular hypertrophy (LVH) is the most common myocardial structural abnormality associated with heart failure with preserved ejection fraction (HFpEF). LVH is driven by neurohumoral activation, increased mechanical load, and cytokines associated with arterial hypertension, chronic kidney disease, diabetes, and other comorbidities. Here we discuss the experimental and clinical evidence that links LVH to diastolic dysfunction and qualifies LVH as one diagnostic marker for HFpEF. Mechanisms leading to diastolic dysfunction in LVH are incompletely understood, but may include extracellular matrix changes, vascular dysfunction, as well as altered cardiomyocyte mechano-elastical properties. Beating cardiomyocytes from HFpEF patients have not yet been studied, but we and others have shown increased Ca(2+) turnover and impaired relaxation in cardiomyocytes from hypertrophied hearts. Structural myocardial remodeling can lead to heterogeneity in regional myocardial contractile function, which contributes to diastolic dysfunction in HFpEF. In the clinical setting of patients with compound comorbidities, diastolic dysfunction may occur independently of LVH. This may be one explanation why current approaches to reduce LVH have not been effective to improve symptoms and prognosis in HFpEF. Exercise training, on the other hand, in clinical trials improved exercise tolerance and diastolic function, but did not reduce LVH. Thus current clinical evidence does not support regression of LVH as a surrogate marker for (short-term) improvement of HFpEF.

Patterns of left ventricular diastolic function in Olympic athletes

BACKGROUND

Whether morphologic left ventricular (LV) changes in elite athletes are associated with altered diastolic properties is undefined. The aim of this study was to investigate LV diastolic properties in a large population of Olympic athletes compared to untrained controls.

METHODS

A total of 1,145 Olympic athletes (61% men), and 154 controls, free of cardiovascular disease, underwent two-dimensional echocardiography, Doppler echocardiography, and Doppler tissue imaging.

RESULTS

Athletes had similar E velocities (87 ± 15 vs 89 ± 16 cm/sec, P = .134) but significantly decreased A velocities (47 ± 10 vs 56 ± 12 cm/sec, P < .001) compared with controls, with increased E/A ratios (1.93 ± 0.50 vs 1.63 ± 0.35, P < .001) and values ranging up to 4.8. Isovolumic relaxation (83 ± 13 vs 71 ± 16 msec, P < .001) and deceleration times (203 ± 40 vs 181 ± 36 msec, P < .001) were longer in athletes compared with controls. Doppler tissue imaging e' (13.8 ± 2.2 vs 16.2 ± 3.7 cm/sec, P < .001) and a' (7.2 ± 1.8 vs 8.5 ± 2.1 cm/sec, P < .001) were lower in athletes than in controls, but their ratio was not different between groups; E/e' ratios (6.37 ± 1.2 vs 5.72 ± 1.33, P < .001) were mildly higher in athletes. Subgroup analysis for type of sport showed that endurance athletes had the lowest A and a' velocities and the largest E/A ratios. Gender analysis revealed that men had significantly lower E and A velocities, as well as e', e'/a' ratios, and E/e' ratios (P < .01), compared with women.

CONCLUSION

This study provides normal values for Doppler echocardiographic and Doppler tissue imaging parameters describing diastolic function in elite athletes, which may be implemented as reference values in the clinical assessment of athlete's heart and prove useful in understanding the physiologic limits of cardiac adaptations in athletes.

Effects that different types of sports have on the hearts of children and adolescents and the value of two-dimensional strain-strain-rate echocardiography

Whether the hypertrophy found in the hearts of athletes is physiologic or a risk factor for the progression of pathologic hypertrophy remains controversial. The diastolic and systolic functions of athletes with left ventricular (LV) hypertrophy usually are normal when measured by conventional methods. More precise assessment of global and regional myocardial function may be possible using a newly developed two-dimensional (2D) strain echocardiographic method. This study evaluated the effects that different types of sports have on the hearts of children and adolescents and compared the results of 2D strain and strain-rate echocardiographic techniques with conventional methods. Athletes from clubs for five different sports (basketball, swimming, football, wrestling, and tennis) who had practiced regularly at least 3 h per week during at least the previous 2 years were included in the study. The control group consisted of sedentary children and adolescents with no known cardiac or systemic diseases (n = 25). The athletes were grouped according to the type of exercise: dynamic (football, tennis), static (wrestling), or static and dynamic (basketball, swimming). Shortening fraction and ejection fraction values were within normal limits for the athletes in all the sports disciplines. Across all 140 athletes, LV geometry was normal in 58 athletes (41.4 %), whereas 22 athletes (15.7 %) had concentric remodeling, 20 (14.3 %) had concentric hypertrophy, and 40 (28.6 %) had eccentric hypertrophy. Global LV longitudinal strain values obtained from the average of apical four-, two-, and three-chamber global strain values were significantly lower for the basketball players than for all the other groups (p < 0.001).

Swimming and the heart

Exercise training is accepted to be beneficial in lowering morbidity and mortality in patients with cardiac disease. Swimming is a popular recreational activity, gaining recognition as an effective option in maintaining and improving cardiovascular fitness. Swimming is a unique form of exercise, differing from land-based exercises such as running in many aspects including medium, position, breathing pattern, and the muscle groups used. Water immersion places compressive forces on the body with resulting physiologic effects. We reviewed the physiologic effects and cardiovascular responses to swimming, the cardiac adaptations to swim training, swimming as a cardiac disease risk factor modifier, and the effects of swimming in those with cardiac disease conditions such as coronary artery disease, congestive heart failure and the long-QT syndrome.

Maximal strength training and increased work efficiency: contribution from the trained muscle bed

Maximal strength training (MST) reduces pulmonary oxygen uptake (Vo(2)) at a given submaximal exercise work rate (i.e., efficiency). However, whether the increase in efficiency originates in the trained skeletal muscle, and therefore the impact of this adaptation on muscle blood flow and arterial-venous oxygen difference (a-vO(2diff)), is unknown. Thus five trained subjects partook in an 8-wk MST intervention consisting of half-squats with an emphasis on the rate of force development during the concentric phase of the movement. Pre- and posttraining measurements of pulmonary Vo(2) (indirect calorimetry), single-leg blood flow (thermodilution), and single-leg a-vO(2diff) (blood gases) were performed, to allow the assessment of skeletal muscle Vo(2) during submaximal cycling [237 ± 23 W; ∼60% of their peak pulmonary Vo(2) (Vo(2peak))]. Pulmonary Vo(2peak) (∼4.05 l/min) and peak work rate (∼355 W), assessed during a graded exercise test, were unaffected by MST. As expected, following MST there was a significant reduction in pulmonary Vo(2) during steady-state submaximal cycling (∼237 W: 3.2 ± 0.1 to 2.9 ± 0.1 l/min). This was accompanied by a significant reduction in single-leg Vo(2) (1,101 ± 105 to 935 ± 93 ml/min) and single-leg blood flow (6,670 ± 700 to 5,649 ± 641 ml/min), but no change in single-leg a-vO(2diff) (16.7 ± 0.8 to 16.8 ±0.4 ml/dl). These data confirm an MST-induced reduction in pulmonary Vo(2) during submaximal exercise and identify that this change in efficiency originates solely in skeletal muscle, reducing muscle blood flow, but not altering muscle a-vO(2diff).

Oxidative stress and cardiac hypertrophy: a review

Cardiac hypertrophy (CH) is an adaptive response of the heart to pressure overload. It is a common pathological feature in the natural course of some major cardiovascular diseases, like, hypertension and myocardial infarction. Cardiac hypertrophy is strongly associated with an increased risk of heart failure and sudden cardiac death. The complex and dynamic pathophysiological mechanisms of CH has been the focus of intense scientific investigation, in an effort to design preventive and curative strategies. Oxidative stress has been identified as one of the key contributing factors in the development of cardiac hypertrophy. In this review, evidences supporting the oxidative stress as a cause of cardiac hypertrophy with emphasis on mitochondrial oxidative stress and possible options for pharmacological interventions have been discussed. Reactive oxygen species (ROS) also activate a broad variety of hypertrophy signaling kinases and transcription factors, like, MAP kinase, NF K-B, etc. In addition to profound alteration of cellular function, ROS modulate the extracellular matrix function, evidenced by increased interstitial and perivascular fibrosis. Translocator protein (TSPO) present in the outer mitochondrial membrane is known to be involved in oxidative stress and cardiovascular pathology. Recently, its role in cardiac hypertrophy has been reported by us. All these evidences strongly provide support to beneficial role of drugs which selectively interfere with the generation of free radicals or augment endogenous antioxidants in cardiac hypertrophy.

Aortic properties and atrial electrophysiology in the young and old football players

OBJECTIVE

The purpose of this study was to investigate the differences between P wave dispersion, aortic elastic properties and transthoracic echocardiographic findings in the young and old football players compared to control groups in order to asses the influence of regular sportive activity on aortic distensibility and its potential effect on atrial electrophysiology.

METHODS

We recruited 42 young football players with a training history of many years. The control group was formed by 27 healthy sedentary men. Twenty-three healthy retired football players of a professional football club aged over 50 years were included in the study as old group and 18 subjects over 50 year old who did not perform regular exercise when they were young were included in the control group of old subjects.

RESULTS

The heart rate and ejection fraction were decreased in the young football players. There were no significant differences in the aortic elastic parameters and P wave dispersion between young football players and control group. But in old subjects with sustained participation in regular sportive activity, the significant difference of left ventricular dimension, wall thickness and systolic functions detected in the young group disappeared while increase in the left atrial diameter became significant.

CONCLUSION

Potential effect of aortic elastic properties which changes with age, on atrial electrophysiology through increasing P wave dispersion was shown.

Androgenic anabolic steroid abuse and the cardiovascular system

Abuse of anabolic androgenic steroids (AAS) has been linked to a variety of different cardiovascular side effects. In case reports, acute myocardial infarction is the most common event presented, but other adverse cardiovascular effects such as left ventricular hypertrophy, reduced left ventricular function, arterial thrombosis, pulmonary embolism and several cases of sudden cardiac death have also been reported. However, to date there are no prospective, randomized, interventional studies on the long-term cardiovascular effects of abuse of AAS. In this review we have studied the relevant literature regarding several risk factors for cardiovascular disease where the effects of AAS have been scrutinized:(1) Echocardiographic studies show that supraphysiologic doses of AAS lead to both morphologic and functional changes of the heart. These include a tendency to produce myocardial hypertrophy (Fig. 3), a possible increase of heart chamber diameters, unequivocal alterations of diastolic function and ventricular relaxation, and most likely a subclinically compromised left ventricular contractile function. (2) AAS induce a mild, but transient increase of blood pressure. However, the clinical significance of this effect remains modest. (3) Furthermore, AAS confer an enhanced pro-thrombotic state, most prominently through an activation of platelet aggregability. The concomitant effects on the humoral coagulation cascade are more complex and include activation of both pro-coagulatory and fibrinolytic pathways. (4) Users of AAS often demonstrate unfavorable measurements of vascular reactivity involving endothelial-dependent or endothelial-independent vasodilatation. A degree of reversibility seems to be consistent, though. (5) There is a comprehensive body of evidence documenting that AAS induce various alterations of lipid metabolism. The most prominent changes are concomitant elevations of LDL and decreases of HDL, effects that increase the risk of coronary artery disease. And finally, (6) the use of AAS appears to confer an increased risk of life-threatening arrhythmia leading to sudden death, although the underlying mechanisms are still far from being elucidated. Taken together, various lines of evidence involving a variety of pathophysiologic mechanisms suggest an increased risk for cardiovascular disease in users of anabolic androgenic steroids.

Therapeutic strategies for diastolic dysfunction: a clinical perspective

Diastolic dysfunction, which is increasingly viewed as being influential in precipitating heart failure and determining prognosis, is often unrecognized and has therapeutic implications distinct from those that occur with systolic dysfunction. In this review, several therapeutic modalities including pharmacologic, nonpharmacologic, and surgical approaches for primary diastolic dysfunction and heart failure will be discussed.

[Correlation between atrial function and functional capacity in highly trained subjects]

AIM

The aim of the study is to show the relationship existing between tissular Doppler imaging (TDI) parameters and functional capacity in highly trained subjects.

METHODS AND PATIENTS

We therefore studied 46 patients including 22 untrained and 24 trained subjects. Each subject had pulsed TDI recording of systolic (S) and diastolic (E and A) longitudinal myocardial velocities in the basal portion of the RV free wall (RV), the septum (sep) and the LV free wall (LV) from apical 4C view. Athletes underwent the same day a cardiopulmonary test during which we measured peak V(O)2 (ml/kg/min) and anaerobic threshold (AT, ml/kg/min) and calculated VE/V(CO)2 slope. We studied differences between echocardiographic parameters in the two groups using Student test. Coefficients of correlations were calculated using the Spearman method.

RESULTS

Differences between two groups concerned Tei index of right (RV) and left ventricle (LV), telediastolic diameter of LV, and A waves on each wall. In athletes RV, sep and LV S waves did not correlate with V(O)2, AT or VE/V(CO)2 RV, sep and LV A waves correlated significantly and negatively with V(O)2, RV and sep A waves negatively with AT, and sep and LV A waves positively with VE/V(CO)2.

CONCLUSION

In athletes, atrial function shows a negative relationship with cardiopulmonary exercise parameters: the lower the proportion of LV filling due to atrial contraction, the better the level of functional capacity. This is probably due to myocardial structure, which allows more efficient early filling in hypertrophic athlete's heart.

Left ventricular diastolic function in trained male weight lifters at rest and during isometric exercise

Individuals involved in intense resistance training present with increased absolute left ventricular (LV) wall thickness and mass and show good systolic responses to isometric exercise. There is no consensus regarding diastolic features and no available information regarding diastolic function in athletes during isometric exertion itself. Therefore, the main aim of this study was to assess diastolic LV function at baseline and during exercise in athletes. The population consisted of 96 men (mean age 29 +/- 7 years): 48 weight lifters who trained for 15 to 20 hours/week and 48 sedentary men. All weight lifters had been active for >6 years, including the 6 months before the study. Ultrasound was performed using a commercially available Doppler echocardiographic system. Isometric exercise was performed in the supine position using a standard 2-hand bar dynamometer. The man end-diastolic volumes at rest were 97 +/- 6 ml in sedentary subjects and 101 +/- 5 ml in weight lifters, increasing to 100 +/- 6 and 118 +/- 11 ml during exercise (p = 0.06 and p <0.01, respectively). End-systolic volumes at rest were similar in the 2 groups, showing significantly greater reductions during exercise in the weight lifters. The mean absolute LV mass was 167 +/- 30 g in sedentary subjects and 202 +/- 32 g in weight lifters (p <0.0001). The mean stroke volume increased from 65 +/- 7 to 86 +/- 7 ml in sedentary subjects and from 70 +/- 6 to 107 +/- 11 ml in weight lifters (intergroup significance p = 0.05 and p <0.01, respectively). A similar pattern of response was documented for the ejection fraction (i.e., significantly greater increases during exercise in weight lifters). Regarding diastolic indexes, in the weight lifters, the mean peak early velocity at rest was 68 +/- 7 cm/s, the mean acceleration rate was 1,242 +/- 176 cm/s/s, and the mean deceleration rate was 414 +/- 44 cm/s/s. All these values were significantly higher than in sedentary subjects, with further increases during exercise (p <0.0001). In weight lifters, the mean peak atrial velocity at rest was 37 +/- 6 cm/s, the mean acceleration time was 55 +/- 4 ms, the mean isovolumic relaxation time was 63 +/- 3 ms, and the mean deceleration time was 164 +/- 4 ms; these values were lower than in sedentary subjects (p <0.0001 for all). In conclusion, intense resistance training leads to enhanced LV diastolic function at rest and during isometric exercise despite the markedly increased LV mass.

Cardiovascular adaptive responses in rats submitted to moderate resistance training

The present study investigated the effects of 8 week of resistance training (RT) on hemodynamic and ventricular function on cardiac myosin ATPase activity, and on contractility of papillary muscles of rats. Groups: control (CO), electrically stimulated (ES), trained at 60% (TR 60%) and 75% of one repetition maximum (1RM) (TR 75%). Exercise protocol: 5 sets of 12 repetitions at 60 and 75% of 1RM, 5 times per week. The CO and ES groups had similar values for parameters analyzed (P > 0.05). Blood pressure (BP), heart rate (13%), left ventricle systolic pressure (LVSP 13%) decreased and cardiac myosin ATPase activity increased in the TR 75% group (90%, P < 0.05). The contractile performance of papillary muscles increased in trained rats (P < 0.05). Eight weeks of RT was associated with lowering of resting BP, heart rate and LVSP, improvements in contractility of the papillary muscle and an increase of cardiac myosin ATPase activity in rats.

Left ventricular mass in elite olympic weight lifters

The existence of resistance training-induced left ventricular (LV) concentric hypertrophy is equivocal. Although some have described significant LV hypertrophy, others have suggested that training-induced LV hypertrophy is proportional to increased fat free mass (FFM) and thus a normal physiologic response to training. Method limitations, steroid use, and type of training may contribute to discrepant findings. Thus, LV structure and volumes are determined using magnetic resonance imaging. Body composition was determined using dual-energy x-ray absorptiometry in 9 elite Olympic weight lifters and 10 age- and weight-matched recreationally active controls. LV structure and volumes were determined by acquiring 6 short- and 3 long-axis magnetic resonance imaging scans of the left ventricle, whereas LV wall thickness was defined as the average of 6 midventricular segment thickness measurements. Weight lifters had the same age, weight, and FFM, but were shorter and had a greater body mass index than controls. LV mass was not different in weight lifters and controls, but was lower in weight lifters when indexed to FFM (2.56 +/- 0.07 vs 2.30 +/- 0.05, p = 0.01). LV mass correlated with FFM (r = 0.49, p = 0.04). However, LV mass was lower in weight lifters for a given FFM. LV wall thickness, as well as end-diastolic, end-systolic, and stroke volumes, were not different between groups. In conclusion, these results refute the hypothesis that resistance training induces LV concentric hypertrophy and suggest that Olympic weight lifting is associated with increases in FFM without a concomitant increase in LV mass.

Cardiac tissue Doppler imaging in sports medicine

The differentiation of training-induced cardiac adaptations from pathological conditions is a key issue in sports cardiology. As morphological features do not allow for a clear delineation of early stages of relevant pathologies, the echocardiographic evaluation of left ventricular function is the technique of first choice in this regard. Tissue Doppler imaging (TDI) is a relatively recent method for the assessment of cardiac function that provides direct, local measurements of myocardial velocities throughout the cardiac cycle. Although it has shown a superior sensitivity in the detection of ventricular dysfunction in clinical and experimental studies, its application in sports medicine is still rare. Besides technical factors, this may be due to a lack in consensus on the characteristics of ventricular function in relevant conditions. For more than two decades there has been an ongoing debate on the existence of a supernormal left ventricular function in athlete's heart. While results from traditional echocardiography are conflicting, TDI studies established an improved diastolic function in endurance-trained athletes with athlete's heart compared with controls.The influence of anabolic steroids on cardiac function also has been investigated by standard echocardiographic techniques with inconsistent results. The only TDI study dealing with this topic demonstrated a significantly impaired diastolic function in bodybuilders with long-term abuse of anabolic steroids compared with strength-trained athletes without abuse of anabolic steroids and controls, respectively.Hypertrophic cardiomyopathy is the most frequent cause of sudden death in young athletes. However, in its early stages, it is difficult to distinguish from athlete's heart. By means of TDI, ventricular dysfunction in hypertrophic cardiomyopathy can be disclosed even before the development of left ventricular hypertrophy. Also, a differentiation of left ventricular hypertrophy due to hypertrophic cardiomyopathy or systemic hypertension is possible by TDI. Besides the evaluation of different forms of left ventricular hypertrophy, the diagnosis of myocarditis is also of particular importance in athletes. Today, it still requires myocardial biopsy. The analysis of focal disturbances in myocardial velocities might be a promising non-invasive method; however, systematic validation studies are lacking. An important future issue for the implementation of TDI into routine examination will be the standardisation of procedures and the establishment of significant reference values for the above-mentioned conditions. Innovative TDI parameters also merit further investigation.

Relative systolic dysfunction in female spontaneously hypertensive rat myocardium

Hypertension and exercise independently induce left ventricular (LV) remodeling and alter LV function. The purpose of this study was to determine systolic and diastolic LV pressure-volume relationships (LV-PV) in spontaneously hypertensive rats (SHR) with and without LV hypertrophy, and to determine whether 6 mo of exercise training modified the LV-PV in SHR. Four-month-old female SHR (n = 20), were assigned to a sedentary (SHR-SED) or treadmill-trained (SHR-TRD) group (approximately 60% peak O2 consumption, 5 days/wk, 6 mo), while age-matched female Wistar-Kyoto rats (WKY; n = 13) served as normotensive controls. The LV-PV was determined using a Langendorff isolated heart preparation at 4 (no hypertrophy: WKY, n = 5; SHR, n = 5) and 10 mo of age (hypertrophy: WKY, n = 8; SHR-SED, n = 8; SHR-TRD, n = 7). At 4 mo, the LV-PV in SHR was similar to that observed in WKY controls. However, at 10 mo of age, a rightward shift in the LV-PV occurred in SHR. Exercise training did not alter the extent of the shift in the LV-PV relative to SHR-SED. Relative systolic function, i.e., relative systolic elastance, was approximately 50% lower in SHR than WKY at 10 mo of age (P < 0.05). Doppler-derived LV filling parameters [early wave (E), atrial wave (A), and the E/A ratio] were similar between groups. LV capacitance was increased in SHR at 10 mo (P < 0.05), whereas LV diastolic chamber stiffness was similar between groups at 10 mo. Hypertrophic remodeling at 10 mo of age in female SHR is manifest with relative systolic decompensation and normal LV diastolic function. Exercise training did not alter the LV-PV in SHR.

Adaptive mechanisms of left ventricular diastolic function to the physiologic load of pregnancy

BACKGROUND

Pregnancy is associated with marked alteration in cardiovascular hemodynamics. Recent reports have characterized the effects on cardiac systolic function. Little has been written on the influences of loading conditions on Doppler measures of diastolic function during pregnancy.

HYPOTHESIS

Stage of pregnancy has an impact on Doppler indices of diastolic function independent of loading conditions, systolic function, and heart rate.

METHOD

Thirty healthy women were prospectively evaluated by serial echocardiography and Doppler examinations at six time periods: 10-12, 18-20, 28-30, 36-38 weeks gestation, 2-4 and 12-14 weeks postpartum. The related effects on indices of diastolic function and its interaction with load, heart rate, mass, and systolic function were determined.

RESULTS

Compared with the nonpregnant state, early (E) velocity increased (0.7+/-0.1-0.9+/-0.1 m/s, p = 0.0001), peaking at 18 weeks and returning to normal levels during late pregnancy. Atrial phase (A) velocity peaked at 18 weeks (0.48+/-0.12-0.60+/-0.13 m/s, p = 0.0001), remaining high throughout the rest of pregnancy. Consequently, the EWA ratio fell significantly during late pregnancy, from 1.9+/-0.4 to 1.4+/-0.3 (p = 0.02). In addition, mean acceleration was significantly increased in early pregnancy with a peak at 18 weeks (7.4+/-1.3 m/s2), returning to nonpregnant level at term (5.7+/-1.4 m/s2, p = 0.0001). Generalized estimating equation using multivariate regression analysis demonstrated that rising heart rate and stroke volume index had an independent effect on A velocity, and that contractility and preload had an independent effect on E velocity. Pregnancy itself had an independent influence on early filling, not explained by the other parameters.

CONCLUSIONS

During normal pregnancy, there is a reversible shift in transmitral flow velocities from early to late filling with a decrease in acceleration, consistent with an increase in ventricular compliance. Changes in heart rate, preload, and contractility, as well as stage of pregnancy influence this alteration.

Patterns of QT dispersion in athletic and hypertensive left ventricular hypertrophy

OBJECTIVE

The objective of this article is to assess whether left ventricular hypertrophy (LVH) due to physical training or of hypertensive patients shows similarities in QT length and QT dispersion.

METHODS

A total of 51 subjects were studied: 17 essential hypertensive patients (27.7 +/- 5.6 years), 17 athletes involved in agonistic activity (canoeing) (24.8 +/- 6.1 years), and 17 normotensive healthy subjects as control group (24.8 +/- 3.6 years). The testing protocol consisted of (1) clinic BP measurement, (2) echocardiography, (3) 12-lead electrocardiographic examination (QT max, QTc max, QT min, QTc min, DeltaQT, DeltaQTc).

RESULTS

There were no significant differences between the body surface area, height, and age of the three groups. Clinic blood pressure was higher in hypertensives (146.5 +/- 45.2/93.5 +/- 4.9 mmHg) versus athletes (120.9 +/- 10.8/77.1 +/- 6.0 mmHg) and controls (123.5 +/- 4.8/78.8 +/- 2.9 mmHg) by definition. Indexed left ventricular mass (LVM/BSA) was significantly greater in both athletes (148.9 +/- 21.1 g/m2) and hypertensives (117.1 +/- 15.2 g/m2) versus controls (81.1 +/- 14.5 g/m2; P < 0.01), there being no statistical difference among them. LVH (LVMI > 125 g/m2) was observed in all athletes, while the prevalence in hypertensives was 50%. In spite of this large difference in cardiac structure there were no significant differences in QT parameters between athletes and the control group, while hypertensive patients showed a significant increase in QT dispersion versus the two other groups (DeltaQT 82 +/- 2.1, 48 +/- 1.3, 49 +/- 2.3 ms; P < 0.01; DeltaQTc 88 +/- 2.0, 47 +/- 1.4, 54 +/- 2.7; P < 0.01).

CONCLUSIONS

LVH induced by physical training activity is not associated with an increase in QT dispersion, whereas pathological increase in LVM secondary to hypertension is accompanied by an increased QT dispersion.

Left ventricular adaptations following short-term endurance training

This study examined the effects of short-term endurance training (ET) on the left ventricular (LV) adaptation and functional response to a series of exercise challenges with increasing intensity. Eight untrained men, with a mean age of 19.4 +/- 0.5 (SE) yr, were studied before and after 6 days of ET consisting of cycling 2 h/day at 65% peak aerobic power (VO2max). LV ejection fraction and LV volumes were assessed by radionuclide angiography at rest and during exercise at three uninterrupted successive work rates corresponding to 53, 68, and 83% of VO2max, each lasting 20 min. ET produced a calculated plasma volume expansion of 11.4 +/- 2.2% (P < 0.05). The increase in plasma volume was accompanied by an increase in VO2max from 45.9 +/- 1.9 to 49.0 +/- 1.0 ml x kg(-1) x min(-1) (P < 0.01) and a decrease in maximal heart rate (197 +/- 2.3 to 188 +/- 1.0 beats/min; P < 0.01). Resting LV function was not changed, although there was a trend for higher stroke volumes (SVs) and improvement in the rapid filling phase of diastole (P = 0.08). Training induced an increase in exercise SV by 10.4, 10.2, and 7% at 53, 68, and 83% VO2max, respectively (P < 0.01). These changes were secondary to increases in end-diastolic volume, which increased significantly at each exercise work rate following training (139 +/- 6 to 154 +/- 6 ml at 53% VO2max, and from 136 +/- 5 to 156 +/- 5 ml at 83% VO2max; P < 0.01). End-systolic volumes were unchanged after ET. A significant bradycardia was observed both at rest (decreasing 7%) and exercise (decreasing 10.4%). LV ejection fraction during exercise was increased slightly by training, reaching significance at the highest work rate, after 60 min of exercise. (P < 0.05). Cardiac output was higher following training at the highest workload (20.8 +/- 2.2 vs. 22.9 +/- 3.1 l/min; P < 0.01). These data indicate that short-term training elicits rapid adaptation to the LV functional response exercise, with increases in SV being secondary to a Frank-Starling effect with minor changes in contractile performance. This produced a volume-induced bradycardia and increase in LV filling, which may be of benefit during prolonged exercise.

Myocardial adaptation in different endurance sports: an echocardiographic study

OBJECTIVE

Of this study was to investigate three groups of highly trained competitive endurance athletes consisting of marathon runners, triathletes and cyclists for differences in left ventricular adaptation.

METHODS

25 marathon athletes, 21 triathlon athletes and 38 cyclists underwent a standard echocardiographic and Doppler study.

RESULTS

The left ventricular internal diameter in diastole divided by body surface area was significantly larger in cyclists than in marathon runners (31.6+/-3.0 vs. 30.0+/-2.0 mm/ m2, p < 0.05) but did not differ of that of triathletes. Left ventricular mass was significantly different between marathon runners and triathletes (253.6+/-63.7 vs. 322.0+/-62.1 g, p < 0.005) and between marathon runners and cyclists (253.6+/-63.7 vs. 314.2+/-79.2 g, p < 0.005). Systolic wall stress was significantly different between the marathon runners and the triathletes (88.4+/-11.7 vs. 78.9+/-11.0 g/cm2 p < 0.05). Only a minority of the endurance athletes showed concentric remodeling (7%), whereas a majority showed eccentric remodeling (65%) of the left ventricle. The prevalence of eccentric remodeling was more apparent in cyclists. There were some specific differences in left ventricular diastolic function between the three different endurance sports, but no left ventricular diastolic dysfunction could be detected.

CONCLUSION

There is a sport-specific left ventricular adaptation in endurance athletes. The triathlon heart and the heart of a cyclist differ significantly from a marathon heart.

Cardiac hypertrophy and diastolic function in physically well trained and in obese men

OBJECTIVE

The aim of the present study was to compare cardiac hypertrophy and diastolic function in extremely obese male patients and physically active adult male subjects of similar age (means 43.0-43.4 y).

DESIGN

Data of male patients referred to our hospital ward in order to reduce their body weight (BW) were compared with those of physically active and nonactive healthy males.

SUBJECTS

The groups contained 21-24 male subjects, very active and moderately active subjects taking part in regular competitive or leisure time physical activity were in the two athletic groups, severely overweight patients constituted the obese group and healthy persons served as controls.

MEASUREMENTS

Two-dimensionally guided M-mode and Doppler recordings.

RESULTS

In comparison with the controls, obese patients had larger left atrial systolic and left ventricular (LV) diastolic internal diameters, LV diastolic wall thickness and muscle mass. Of the body size-related indices, only the left atrial systolic diameter index was significantly higher. LV systolic and diastolic functions were impaired as indicated by a decreased ejection fraction (EF), higher heart rate (HR), decreased E/A quotient and increased isovolumetric relaxation time. In the physically very active subjects, a thicker LV diastolic wall was seen without LV dilatation. Body size-related wall thickness and muscle mass were significantly higher than in the controls. EF and HR did not differ from those of the controls.

CONCLUSION

The most useful help to distinguish between physiological and pathological left ventricular hypertrophy can be to investigate diastolic functions. The most salient difference appeared in diastolic function, because E/A quotient was higher in the very active subjects than in the controls and it was the lowest in the obese persons.

Exercise and diastolic function after myocardial infarction

PURPOSE

The purpose of this study was to determine the effects of exercise training on LV geometry and LV diastolic function in a rat model of MI.

METHODS

One month after MI induced by ligation of the left anterior descending artery (N = 45) or sham operation (N = 26), rats were randomized to either a sedentary or exercise group. Exercise consisted of treadmill running at 24 m.min-1, 1 h.d-1, 5 d.wk-1, for 3 wk. Passive LV pressure volume relationships were established with an isolated, red-cell-perfused Langendorff preparation. Infarct size was determined histologically and categorized as small (<30% of LV) or large (> or =30% of LV).

RESULTS

LV end-diastolic pressure-volume relationships were shifted rightward with increasing infarct size (P < 0.05). Exercise training further shifted the LV end-diastolic pressure-volume relationships rightward in sham, small MI and large MI (P < 0.05). Peak LV developed pressure was comparable in sedentary and exercised-trained hearts in sham, small MI, and large MI. LV diameter and septal wall thickness were greatest in large MI (P < 0.05). Exercise-trained hearts showed a tendency for a greater LV diameter and septal wall thickness in sham, small MI, and large MI. Scar thinning was most notable in large MI (P < 0.05).

CONCLUSION

Moderate-intensity treadmill running induces myocardial remodeling and a rightward shift in the LV end-diastolic pressure-volume relationship after MI, an adaptation similar to what is observed with exercise training in sham hearts without MI.

Echocardiographic evaluation of wheelchair-bound basketball players

BACKGROUND

Cardiopulmonary function in sedentary men whose lower limbs have been immobilized for years has been shown to be markedly lower than normal. However, the cardiopulmonary function of paraplegics who regularly activate their upper limps and trunk has been suggested to be almost normal in a few studies. The purpose of the present study was to evaluate the left ventricular dimensions, left ventricular mass, systolic and diastolic function in adolescent wheelchair-bound basketball players using echocardio-graphy, and to compare the results with those of sedentary adolescents unable to use their lower extremities and the results of able bodied controls.

METHODS

The study group consisted of 22 male adolescent high school students who were unable to use their lower extremities: 11 were members of a high school basketball team who had been regularly playing basketball for at least 2 years, and 11 were sedentary adolescents none of whom was engaged in any kind of routine training program. The control group consisted of 11 healthy able-bodied male adolescents of similar age.

RESULTS

There were no significant differences in left ventricular dimensions and wall thickness, aortic root, left atrium diameters, or left ventricular filling characteristics between the three groups. Wheelchair-bound basketball players had increased left ventricular ejection fraction and shortening fraction compared with the sedentary unable-bodied individuals. Although left ventricular ejection fractions were significantly lower than in normal adolescents, all ejection fraction values except one were within the normal limits in the unable-bodied basketball players.

CONCLUSION

The results of the present study suggest that an upper extremity exercise program and sports such as basketball can improve the cardiac functions and additional echocardiographic functions of people unable to use their lower extremities, potentially to normal levels.

Coronary microcirculation into different models of left ventricular hypertrophy-hypertensive and athlete's heart: a contrast echocardiographic study

The study was carried out in two different models of left ventricular hypertrophy: athlete's heart and essential arterial hypertension. Three groups of strictly age-matched males were studied: one group of 10 young adult untreated essential hypertensive patients (H), a second group of 10 athletes (A), and a group of 10 healthy individuals as controls (C). A Sonos 5500 echograph with S4 harmonic transducer was used with Levovist (ultrasonic tracer) before and after dipyridamole injection; digitised images of quantitative myocardial contrast echocardiography were collected with Power Harmonic Doppler. Angio images were analysed using dedicated PC software by placing a region-of-interest on the septum. Peak intensity, half-time (HT), the area under the curve of appearance and disappearance of microbubbles at 2/3 of PI, both in absolute and indexed values (/LVMi), were sampled. The per cent increase of PI after dipyridamole was significantly higher in C (+73%, P < 0.01) than in H (+31%) and in A (+33%) (P < 0.05). The area of appearance was significantly lower in H in comparison with C and A, both at rest and after vasodilatation. The disappearance area after dipyridamole was significantly higher in C and in A (+124%) than in H (+104%) (P < 0.05). Some hypothesis could be made: an impairment in the coronary microcirculatory function in hypertensive patients could be because of an in-crease in the arteriolar resistance. Angiogenesis and several different functional adaptations are the mechanisms that allow an optimal distribution of oxygen and of substrates to the hypertrophied myocardium of the athletes.

Midwall myocardial shortening in athletic left ventricular hypertrophy

BACKGROUND

Patients with pathological left ventricular hypertrophy have depressed midwall systolic shortening in spite of normal indices of left ventricular chamber function and a reduced midwall function has been observed to be an independent predictor of cardiovascular risk. Whether midwall shortening is depressed in physiological hypertrophy is unknown.

METHODS

Forty-two subjects, 27 athletes and 15 age- and sex-matched normal control subjects (group 1) were studied. The athletes were divided into those with eccentric hypertrophy (group 2) and those with concentric hypertrophy (group 3). Systolic left ventricular function was assessed at the midwall and endocardium using two-dimensional echocardiography in all subjects.

RESULTS

Left ventricular mass index was significantly greater in both athletic groups than in controls (group 1, 101+/-5.8 g/m(2), group 2, 141+/-11.1*, group 3, 155+/-5.8*; *P<0.01 compared with group 1). Left ventricular systolic function assessed at the endocardium was similar among all three groups (ejection fraction: group 1, 66.2+/-2.38, group 2, 66.8+/-1.44, group 3, 63.7+/-1.66%; endocardial fractional shortening: group 1, 37.1+/-1.71, group 2, 37.6+/-1.13, group 3, 35.1+/-1.25%). However, fractional shortening at the midwall was reduced in the concentric hypertrophy athletes compared with the other two groups (midwall fractional shortening: group 1, 21.9+/-1.1, group 2, 21.9+/-0.86, group 3, 18.4+/-0.96*%; P<0.05 compared with groups 1 and 2).

CONCLUSION

Subjects with physiological concentric hypertrophy have depressed midwall fractional shortening. This suggests that the observed discrepancy between midwall and endocardial shortening in patients with left ventricular hypertrophy is likely to be a function of the geometry and not necessarily a reflection of pathology within the myocardium.

Assessment of regional systolic and diastolic wall motion velocities in highly trained athletes by pulsed wave Doppler tissue imaging

We studied the relationship between left ventricular (LV) function and the increased LV mass in 18 highly trained rowing athletes (14 men, 4 women; mean age 20.7 +/- 4.5 years) using pulsed wave Doppler tissue imaging (PWDTI). Thirteen untrained volunteers, matched for age and body mass index, acted as control participants. Peak systolic, early diastolic (Ev), and late diastolic (Av) myocardial velocities (cm/s); Ev/Av ratio; and isovolumic relaxation time (ms) were measured at the level of basal lateral wall and basal posterior interventricular septum (bas-IVS) segments. In comparison with control participants, athletes showed a greater LV cavity size (P <.05), wall thickness (IVS, P <.001; posterior wall, P <.01), and mass index (P <.001). In athletes, systolic velocity of bas-IVS had increased (P <.001) and was positively correlated with IVS thickness (r = 0.66, P <.005) and LV mass index (r = 0.71, P <.001). Of the PWDTI-measured diastolic indexes, Ev/Av ratio significantly increased in athletes in comparison with control participants in both the examined segments (bas-IVS, P <.05; basal lateral wall, P <.05). When Ev and Av were separately considered, a different behavior was found in the 2 segments: Ev significantly increased in the basal lateral wall (P <.005); Av significantly decreased in the bas-IVS. The increase in the systolic velocity of bas-IVS suggests that septum greatly contributes to the longitudinal LV systolic shortening and increase of stroke volume in athletes compared with untrained participants. Moreover, the behavior of PWDTI diastolic velocities suggests a more effective relaxation activity in the longitudinal axis at the level of lateral wall. This study suggests therefore the usefulness of PWDTI in the assessment of functional properties of "athlete's heart" and differentiation from pathologic cardiac conditions.

Echocardiographic characteristics of male athletes of different age

Two dimensionally guided M mode and Doppler echocardiographic data for 578 male subjects (106 non-athletic and 472 athletes) were analysed from two aspects: (a) in the young adult category (19--30 years of age), competitors in different groups of sports were studied; (b) in the different age groups (children, 10--14 years; adolescent juniors, 15--18 years; young adults, 19--30 years; adults, 31--44 years; older adults 45--60 years), data for athletes and non-athletes were compared. Morphological variables were related to body size by indices in which the exponents of the numerator and denominator were matched. Morphological signs of athletic heart were most consistently evident in the left ventricular muscle mass: in the young adult group, the highest values were seen in the endurance athletes, followed by the ball game players, sprinters/jumpers, and power athletes. A thicker muscular wall was the main reason for this hypertrophy. Internal diameter was only increased in the endurance athletes, and this increase was more evident in the younger groups. The E/A quotient (ratio of peak velocity during early and late diastole) indicated more effective diastolic function in the endurance athletes. The values for E/A quotient also suggested that regular physical activity at an older age may protect against age dependent impairment of diastolic function.

Detection of changes in diastolic function by pulmonary venous flow analysis in women athletes

BACKGROUND

Left ventricular cavity dimension, wall thickness, relaxation, and filling increase with exercise training and have a role in enhancing physical performance. We probed whether changes in diastole may develop separately from those in cardiac morphometry and still contribute to improve physical performance. Challenging diastole by preload reduction with standing and integrating mitral flow analysis with the pulmonary venous flow analysis were viewed as a means for detecting fine diastolic variations.

METHODS

Patterns of mitral, tricuspid, and pulmonary venous flow were evaluated by echo Doppler imaging in the supine and standing positions in 11 long-distance runner women athletes participating in training programs and having no or very mild cardiac morphologic alterations and were compared with those in 11 healthy women active in daily life not participating in training programs. Maximal exercise tolerance was tested in both groups with a treadmill with use of the standard Bruce protocol.

RESULTS

Echocardiographic left ventricular mass index and mitral and pulmonary flow patterns in athletes and controls were similar while they were supine. Major (P<.01) percent variations and differences between athletes and controls with standing were smaller decrease in right (-12% +/- 5% vs -29% +/- 5%) and left ventricular (-3% +/- 1% vs -9% +/- 2%) dimensions and stroke volume (-7% +/- 4% vs -23% +/- 4%), smaller lengthening of early mitral deceleration (+7% +/- 4% vs +18% +/- 5%), and isovolumic relaxation (-3% +/- 5% vs +15% +/- 7%) times. Athletes showed greater reduction in pulmonary S wave peak velocity (-25% +/- 10% vs -12.5% +/- 7%) and time velocity integral (Si) (-50% +/- 9% vs -21% +/- 8%), greater increases in pulmonary venous diastolic (D) wave peak velocity(+20% +/- 9% vs +12% +/- 10%, meters per second), and time velocity integral (Di) (+81% +/- 16% vs +27% +/- 14%) and greater decrease of S/D(-30% +/- 6% vs -18% +/- 5%) and Si/Di (-70% +/- 10% vs -33% +/- 5%) ratios. At multivariate analysis standing Si/Di was the strongest independent predictor of better exercise tolerance (peak exercise time 1035 +/- 88 sec in athletes, 751 +/- 20 in controls).

CONCLUSIONS

Pulmonary flow analysis in athletes while standing can detect changes in diastolic function that are dissociated from apparent left ventricular morphologic alterations, are undetected in the supine position, and may, in part, determine exercise performance.

Pulsed Doppler tissue imaging in endurance athletes: relation between left ventricular preload and myocardial regional diastolic function

The aim of this study was to assess the effects of endurance training on myocardial regional systolic and diastolic function by pulsed Doppler tissue imaging (DTI). Twenty male water polo players and 20 male control subjects underwent standard Doppler echocardiography and pulsed DTI, performed in apical views by placing a sample volume on left ventricular (LV) basal septal and inferior walls. Age, body surface area, and blood pressure were comparable between the 2 groups, with lower heart rate in athletes (p <0.001). They had significantly increased LV mass index (due to both higher wall thickness and end-diastolic diameter), greater endocardial fractional shortening, higher transmitral early/atrial (E/A) peak velocities ratio. In athletes, DTI analysis showed significantly prolonged myocardial deceleration time and greater myocardial E/A peak velocity ratio of septal and inferior walls, whereas myocardial early peak velocity was increased (p <0.01) only at the inferior wall. In the overall group, we found univariate relations of septal and inferior E/A peak velocity ratio and myocardial deceleration time with LV mass levels, and, in particular, with the sum of wall thickness. By separate multivariate analyses, however, these relations disappeared, being dependent on heart rate degree. Another association found between LV end-diastolic diameter and myocardial early diastolic wave peak velocity of the inferior wall (r = 0.68, p <0.0001) remained significant (standardized beta coefficient 0.60, p <0.00001), even after adjusting for heart rate, body surface area, age, and stroke volume (R(2) = 0.71, p <0.00001). In conclusion, DTI is a useful tool for detecting regional changes in myocardial function induced by training, because athletes present with an improvement in diastolic passive properties of myocardium. The higher early diastolic velocity of the inferior wall and its relation to increased preload may represent an indicator of aerobic training, allowing quantification of the degree of LV adaptation to endurance exercise.

Comparison of cardiovascular adaptations to long-term arm and leg exercise in wheelchair athletes versus long-distance runners

The effect of long-term arm exercise on cardiac morphology and function is unknown. To study these effects, highly trained wheelchair athletes were compared with long-distance runners and controls. In addition, the wheelchair athletes were compared with the long-distance runners to determine if long-term leg exercise confers a training effect during the performance of dynamic arm exercise. The study included 31 male subjects (mean age of 33+/-5 years), who comprised 3 groups matched for age and weight: wheelchair athletes (n = 9), long-distance runners (n = 12), and healthy controls (n = 10). All underwent echocardiography at rest and arm ergometry exercise testing with expiratory gas analysis. The peak work rate during arm exercise was highest among the wheelchair athletes, and was significantly higher in both groups of trained athletes compared with the control group (p<0.001). Runners demonstrated a significantly lower submaximal heart rate response to arm exercise compared with wheelchair and control subjects. Wheelchair athletes had increased left ventricular (LV) volume and mass by echocardiography compared with controls, but not to the same degree as that of runners. Although chamber dimensions and wall thickness did not differ among the groups, the LV volume index tended to be largest in the runners. Doppler indexes of diastolic LV filling were similar between the trained and untrained subjects. These data demonstrate that both long-term arm and leg exercise yield increases in LV volume and mass compared with untrained control subjects, although to a lesser degree in arm-trained athletes. Runners demonstrated a transfer of training effect in the performance of dynamic arm exercise, as demonstrated by their ability to achieve a higher peak work rate than controls, and showed a lower heart rate response to submaximal exercise than the wheelchair athletes and control subjects.

The athlete's heart. A meta-analysis of cardiac structure and function

BACKGROUND

It has been postulated that depending on the type of exercise performed, 2 different morphological forms of athlete's heart may be distinguished: a strength-trained heart and an endurance-trained heart. Individual studies have not tested this hypothesis satisfactorily.

METHODS AND RESULTS

The hypothesis of divergent cardiac adaptations in endurance-trained and strength-trained athletes was tested by applying meta-analytical techniques with the assumption of a random study effects model incorporating all published echocardiographic data on structure and function of male athletes engaged in purely dynamic (running) or static (weight lifting, power lifting, bodybuilding, throwing, wrestling) sports and combined dynamic and static sports (cycling and rowing). The analysis encompassed 59 studies and 1451 athletes. The overall mean relative left ventricular wall thickness of control subjects (0.36 mm) was significantly smaller than that of endurance-trained athletes (0.39 mm, P=0.001), combined endurance- and strength-trained athletes (0.40 mm, P=0.001), or strength-trained athletes (0.44 mm, P<0.001). There was a significant difference between the 3 groups of athletes and control subjects with respect to left ventricular internal diameter (P<0. 001), posterior wall thickness (P<0.001), and interventricular septum thickness (P<0.001). In addition, endurance-trained athletes and strength-trained athletes differed significantly with respect to mean relative wall thickness (0.39 versus 0.44, P=0.006) and interventricular septum thickness (10.5 versus 11.8 mm, P=0.005) and showed a trend toward a difference with respect to posterior wall thickness (10.3 versus 11.0 mm, P=0.078) and left ventricular internal diameter (53.7 versus 52.1 mm, P=0.055). With respect to cardiac function, there were no significant differences between athletes and control subjects in left ventricular ejection fraction, fractional shortening, and E/A ratio.

CONCLUSIONS

Results of this meta-analysis regarding athlete's heart confirm the hypothesis of divergent cardiac adaptations in dynamic and static sports. Overall, athlete's heart demonstrated normal systolic and diastolic cardiac functions.

Myocardial diastolic function and exercise

There are several important links between aerobic exercise performance and the diastolic phase of the cardiac cycle. During acute exercise, diastolic function must be augmented in order for left ventricular filling to match increased left ventricular output, i.e., cardiac output. This challenges the myocardium because the shortened duration of diastole during exercise may compromise left ventricular filling, thereby limiting the stroke volume. Additionally, left ventricular filling must be accomplished at relatively low filling pressures, otherwise pulmonary vascular congestion may occur. Left ventricular diastolic function may be impaired in the elderly and/or in individuals with ischemic coronary syndromes. Regular aerobic exercise training appears to enhance left ventricular diastolic function and may benefit patients with clinically relevant "diastolic dysfunction." The purpose of this paper is to discuss the relative importance between diastole and exercise and to review some of the involved putative mechanisms.

Muscular strength training is associated with low arterial compliance and high pulse pressure

Aerobic exercise training increases arterial compliance and reduces systolic blood pressure, but the effects of muscular strength training on arterial mechanical properties are unknown. We compared blood pressure, whole body arterial compliance, aortic impedance, aortic stiffness (measured by beta-index and carotid pulse pressure divided by normalized systolic expansion [Ep]), pulse wave velocity, and left ventricular parameters in 19 muscular strength-trained athletes (mean+/-SD age, 26+/-4 years) and 19 sedentary controls (26+/-5 years). Subjects were healthy, non-steroid-using, nonsmoking males, and athletes had been engaged in a strength-training program with no aerobic component for a minimum of 12 months. There was no difference in maximum oxygen consumption between groups, but handgrip strength (mean+/-SEM, 44+/-2 versus 56+/-2 kg; P<0.01) and left ventricular mass (168+/-8 versus 190+/-8 g; P<0.05) were greater in athletes. Arterial stiffness was higher in athletes, as evidenced by lower whole body arterial compliance (0.40+/-0.04 versus 0.54+/-0.04 arbitrary compliance units; P=0.01), higher aortic characteristic impedance (1.55+/-0.13 versus 1.18+/-0.08 mm Hg. s. cm-1; P<0.05), beta-index (4.6+/-0.2 versus 3.8+/-0.4; P<0. 05), and ln Ep (10.86+/-0.06 versus 10.60+/-0.08; P<0.01). Femoral-dorsalis pedis pulse wave velocity was also higher in the athletes, but carotid-femoral pulse wave velocity was not different. Furthermore, both carotid (56+/-3 versus 44+/-2 mm Hg; P<0.001) and brachial (60+/-3 versus 50+/-2 mm Hg; P<0.01) pulse pressures were higher in the athletes, but mean arterial pressure and resting heart rate did not differ between groups. These data indicate that both the proximal aorta and the leg arteries are stiffer in strength-trained individuals and contribute to a higher cardiac afterload.