Alterations in Left Ventricular Structure and Diastolic Function in Professional Football Players: Assessment by Tissue Doppler Imaging and Left Ventricular Flow Propagation Velocity

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.

Running away from cardiovascular disease at the right speed: The impact of aerobic physical activity and cardiorespiratory fitness on cardiovascular disease risk and associated subclinical phenotypes

Higher levels of physical activity (PA) and cardiorespiratory fitness (CRF) are associated with lower risk of incident cardiovascular disease (CVD). However, the relationship of aerobic PA and CRF with risk of atherosclerotic CVD outcomes and heart failure (HF) seem to be distinct. Furthermore, recent studies have raised concerns of potential toxicity associated with extreme levels of aerobic exercise, with higher levels of coronary artery calcium and incident atrial fibrillation noted among individuals with very high PA levels. In contrast, the relationship between PA levels and measures of left ventricular structure and function and risk of HF is more linear. Thus, personalizing exercise levels to optimal doses may be key to achieving beneficial outcomes and preventing adverse CVD events among high risk individuals. In this report, we provide a comprehensive review of the literature on the associations of aerobic PA and CRF levels with risk of adverse CVD outcomes and the preceding subclinical cardiac phenotypes to better characterize the optimal exercise dose needed to favorably modify CVD risk.

Impact of Exercise Training on Cardiac Function Among Patients With Type 2 Diabetes: A SYSTEMATIC REVIEW AND META-ANALYSIS

PURPOSE

Type 2 diabetes (T2D) is associated with subclinical abnormalities in left ventricular function and an increased downstream risk for heart failure. Exercise training has been associated with significant improvement in cardiorespiratory fitness among these patients. However, its impact on cardiac function is not well established.

METHODS

We conducted a meta-analysis including all randomized and nonrandomized trials that evaluated effects of exercise training on cardiac function among patients with T2D. Primary outcomes were measures of left ventricular systolic (global longitudinal strain) and diastolic (early diastolic velocity [é]) function. The effects of exercise training on peak oxygen uptake; other markers of diastolic dysfunction: mitral peak early-to-late diastolic filling velocity (E/A), mitral inflow to annular ratio (E/é), and deceleration time (DT); and systolic velocity were also assessed.

RESULTS

Our study included 441 patients enrolled in 6 trials. Exercise training significantly improved early diastolic velocity (standardized mean difference [SMD], 0.58; 95% CI, 0.09-1.07), global longitudinal strain (SMD, 0.62; 95% CI, 0.04-1.21), and peak oxygen uptake (SMD, 1.43; 95% CI, 0.51-2.35) as compared with control group. However, no significant changes were observed in other markers of diastolic function (E/A, E/é and DT) and systolic velocity.

CONCLUSION

Exercise training in patients with T2D is associated with a significant improvement in some echocardiographic indicators of systolic and diastolic function and cardiorespiratory fitness. These findings suggest that exercise training may improve subclinical systolic and diastolic dysfunction in patients at risk for clinical heart failure.

The association between physical activity and cardiac performance is dependent on age: the Copenhagen City Heart Study

This study aimed to test the hypothesis that regular physical activity is associated with improved cardiac function measured by tissue Doppler imaging (TDI) in the general population. Within a large prospective community-based population study, cardiac function was assessed in 2221 persons by TDI. Longitudinal displacement (LD), early diastolic velocity (e'), and myocardial performance index (MPI) was obtained by TDI. Linear univariable and multivariable regression analyses were performed in relation to age groups (< 50 years, 50-65 years, > 65 years) and self-reported level of physical activity: I (inactivity), II (light activity), III (moderate activity), and IV (high-level activity). Participants < 50 years in the most active group had significantly better cardiac performance when compared to all other activity levels (higher levels of e', LD, and lower levels of MPI). The findings remained with statistical significance after adjustment for sex, ischemic heart disease, diabetes, hypertension, and body mass index (e' = 11.0, 95% CI (10.4-11.6), p < 0.001; LD = 12.8 (12.3-13.4), p < 0.003; MPI: 0.40 (0.38-0.42), p = 0.02). In age > 65 years, there was a tendency of impaired cardiac function in higher levels of exercise. Interaction analysis revealed that age significantly modified the association between physical activity and cardiac function (p < 0.001). We found a positive association between higher level of physical activity and improved cardiac function in younger persons (< 50 years). In the general population, however, the association interacted with age and amongst persons above 65 years there was a negative association between higher level of physical activity and cardiac function.

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.

Cardiovascular health profile of elite female football players compared to untrained controls before and after short-term football training

This study examined the intermittent exercise performance and cardiovascular health profile in elite female football players in comparison to untrained young women, as well as a subgroup subjected to football training 2x1 h · week(-1) for 16 weeks. Twenty-seven Danish national team players (elite trained, ET) and 28 untrained women (UT) underwent dual-energy X-ray absorptiometry-scanning (DXA), comprehensive transthoracic echocardiography, treadmill and Yo-Yo Intermittent Endurance level 2 (IE2) testing. Eight women in UT were also tested after the football training period. Maximal oxygen uptake rate (VO2max), peak ventilation and peak lactate were 40, 18 and 51% higher (P< 0.01) in ET than UT, respectively. Cardiac dimensions and function were greater in ET than UT, with left ventricular diastolic diameter, right ventricular diastolic diameter, tricuspid annular plane systolic excursion (TAPSE) and peak transmitral flow in early diastole divided by peak transmitral flow velocity in late diastole during atrial contraction (E/A-ratio) being 13, 19, 27 and 41%, respectively, greater in ET than UT (P< 0.001 to< 0.05). Yo-Yo IE2 performance was 7-fold higher in ET than UT (1772 ± 508 vs. 234 ± 66 m, P< 0.001), fat mass was 51% lower (P< 0.001) and high density lipoprotein (HDL) cholesterol levels were 20% higher (P< 0.01). Sixteen weeks of football elevated VO2max and Yo-Yo IE2 performance by 16 and 40%, respectively, and lowered fat mass by 6%. Cardiac function was markedly improved by 16 weeks of football training with 26 and 46% increases in TAPSE and E/A ratio, respectively, reaching levels comparable to ET. In summary, elite female football players have a superior cardiovascular health profile and intermittent exercise performance compared to untrained controls, but short-term football training can markedly improve the cardiovascular health status.

Acute effects of cigarette smoking on the cardiac diastolic functions

BACKGROUND

Smoking is an independent risk factor for coronary heart diseases and it increases all causes of cardiovascular morbidity and mortality.

AIM OF THE WORK

To assess the acute effect of cigarette smoking on ventricular diastolic functions (LV and RV) in healthy, young, and slim smokers.

METHODS

Thirty volunteers who had recently commenced smoking (less than one year) and who smoked 1-2 cigarettes per day, underwent ECG, 2D and M-mode echocardiography, standard Doppler echocardiography, pulsed TDI (tissue Doppler imaging) on septal and lateral side of mitral annulus and lateral tricuspid annulus. Vp values were measured. The investigator asked them to hold smoking for at least two days after which echocardiographic examination was conducted before smoking one cigarette and the second examination conducted immediately after smoking one cigarette containing at least 0.4 mg of nicotine.

RESULTS

Doppler findings over the mitral valve showed the E wave was significantly reduced from 82.7 ± 10.4 to 74.6 ± 10.4 after smoking; the A wave increased; the E/A ratio was reduced from 1.5 ± 0.3 to 1.2 ± 0.2; the E' septal significantly decreased (15.3 ± 2.4 vs. 11.2 ± 1.1) after smoking, and the E/E' ratio increased from 5.5 ± 1.1 to 6.7 ± 1.1. Doppler findings over the tricuspid valve showed the E wave was reduced from 60.6 ± 9.7 to 52.7 ± 9.6; the A wave increased from 42.2 ± 6.5 to 50.1 ± 6.6; and the E/A ratio decreased (1.45 ± 0.25 vs. 1.06 ± 0.19). The E' significantly decreased from 14.1 ± 1.8 to 10.9 ± 2.4, while the A' increased (10.2 ± 2.4 vs. 12.7 ± 3.6) after smoking; and the IVRT of the RV was significantly prolonged from 62.9 ± 7.5 to 68.7 ± 7.9 after smoking. The Vp was markedly reduced from 67.8 ± 8 to 55.2 ± 3.5 after smoking. These findings reflected on the LV filling pressure (LVFvp) which increased from 9.8 ± 1.4 to 10.5 ± 1.3 after smoking. All changes were statistically significant at P < 0.001.

CONCLUSIONS

Our study reveals that cigarette smoking can result in significant acute alteration in the diastolic functions of both ventricles.

Doppler echocardiography in athletes from different sports

BACKGROUND

Studies have shown cardiac changes induced by intense and regular physical activity. The purpose of this study was to evaluate cardiac structures and function in soccer players, cyclists and long-distance runners, and compare them with non-athlete controls.

MATERIAL AND METHODS

Cardiac structural, systolic, and diastolic function parameters in 53 athletes and 36 non-athlete controls were evaluated by Doppler echocardiography.

RESULTS

Athletes presented higher left atrial volume, left ventricular (LV) thickness, and LV and right ventricular (RV) diastolic diameters (LVDD and RVDD, respectively) compared to non-athletes. Left atrium and LVDD were higher in cyclists than runners, and RVDD was higher in cyclists than soccer players. LV mass index was higher in athletes, and cyclists had higher values than runners and soccer players. LV systolic function did not differ significantly between groups. The only altered index of LV diastolic function was a higher E/A ratio in cyclists compared to controls. There was no difference in LV E/E' ratio. RV systolic function evaluated by tissue Doppler imaging was higher in cyclists and soccer players than runners. There were no conclusive differences in RV diastolic function.

CONCLUSIONS

Soccer players, runners and cyclists had remodeling of left and right ventricular structures compared to controls. Cardiac remodeling was more intense in cyclists than runners and soccer players.

Fetal myocardial tissue Doppler indices before birth physiologically change in proportion to body size adjusted for gestational age in low-risk term pregnancies

BACKGROUND

Few studies have investigated the relationship between myocardial tissue Doppler parameters and fetal size adjusted for gestational age and its trend has been controversial.

AIMS

To investigate fetal cardiac function before birth using tissue Doppler imaging (TDI: indicated by the prime symbol (')) in low-risk term pregnancies by comparing the TDI parameters with gestational age-specific birth weight percentiles and z scores.

STUDY DESIGN AND MEASUREMENTS

Interventricular septum, left and right ventricular myocardial peak early diastolic (E'), late diastolic (A') and systolic (S') velocities, E'/A' ratios, myocardial performance index (MPI') and umbilical artery pulsatility index were measured within three days before birth in 76 low-risk term pregnancies, including appropriate for gestational age (AGA, n=50), small for gestational age (SGA, n=10), and large for gestational age (LGA, n=16) subjects.

RESULTS

Myocardial peak velocities showed higher in the LGA and lower in the SGA compared with the AGA group, and All S' positively correlated with birth weight (r=0.51-0.57). All z scores of S' demonstrated a positive correlation with birth weight z score (Spearman r=0.45-0.53). MPI' was significantly higher in the SGA and lower in the LGA compared with the AGA group. All MPI' negatively correlated with birth weight (r=-0.55 to -0.65). All z scores of MPI' showed a negative correlation with birth weight z score (Spearman r=-0.40 to -0.56).

CONCLUSIONS

Fetal myocardial peak velocities and MPI' physiologically changed in proportion to body size adjusted for gestational age in low-risk term pregnancies.

Exercise-induced cardiac remodeling

Early investigations in the late 1890s and early 1900s documented cardiac enlargement in athletes with above-normal exercise capacity and no evidence of cardiovascular disease. Such findings have been reported for more than a century and continue to intrigue scientists and clinicians. It is well recognized that repetitive participation in vigorous physical exercise results in significant changes in myocardial structure and function. This process, termed exercise-induced cardiac remodeling (EICR), is characterized by structural cardiac changes including left ventricular hypertrophy with sport-specific geometry (eccentric vs concentric). Associated alterations in both systolic and diastolic functions are emerging as recognized components of EICR. The increasing popularity of recreational exercise and competitive athletics has led to a growing number of individuals exhibiting these findings in routine clinical practice. This review will provide an overview of EICR in athletes.

Cardiac magnetic resonance assessment of left and right ventricular morphologic and functional adaptations in professional soccer players

BACKGROUND

Professional, long-term physical training is associated with cardiac morphologic and functional changes that depend on the type of exercise performed. So far, the specific effect of soccer training on cardiac morphology has not been investigated with cardiac magnetic resonance imaging (CMRI). We sought to use CMRI to study left ventricular (LV) and right ventricular (RV) morphologic and functional adaptations in professional soccer players.

METHODS

Twenty-nine male professional soccer players (mean age 24.6 +/- 3.9 years, range 18-31 years) in different playing positions and 29 nonathlete male controls (27.0 +/- 3.7 years, 21-34 years) underwent CMRI. Electrocardiographic-gated steady-state free-precession cine CMRI was used to measure myocardial mass (MM), end-diastolic volume (EDV) and end-systolic volume, stroke volume (SV), ejection fraction, and cardiac index at rest. We calculated the ventricular remodeling index (RI) to describe the pattern of cardiac hypertrophy.

RESULTS

Ventricular volume and mass indices were significantly (P < .001) higher in athletes. LVEDV and RVEDV on MRI was above normal in 27/29 athletes. There was a strong positive correlation between EDV and myocardial mass (P < .01). The LVRI and RVRI were similar (0.73 +/- 0.1 g/mL; 0.22 +/- 0.01 g/mL) to that of controls (0.71 +/- 0.1 g/mL; 0.22 +/- 0.01 g/mL). No significant differences were observed for LV ejection fraction and cardiac index. Neither the comparison of athletes in different playing positions nor the comparison of younger and older players revealed statistically significant differences.

CONCLUSION

Cardiac magnetic resonance imaging measurements enable studying the mechanisms of LV and RV adaptation in professional soccer players and reflect the ventricular response to combined endurance and strength based training.

High output heart failure

The symptoms and signs of heart failure can occur in the setting of an increased cardiac output and has been termed 'high output heart failure'. An elevated cardiac output with clinical heart failure is associated with several diseases including chronic anaemia, systemic arterio-venous fistulae, sepsis, hypercapnia and hyperthyroidism. The underlying primary physiological problem is of reduced systemic vascular resistance either due to arterio-venous shunting or peripheral vasodilatation. Both scenarios can lead to a fall in systemic arterial blood pressure and neurohormonal activation leading to overt clinical heart failure. In contrast to low output heart failure, clinical trial data in this area are lacking. The use of conventional therapies for heart failure, such as angiotensin converting enzyme inhibitors, angiotensin receptor blockers and certain beta-blockers with vasodilatory properties, is likely to further reduce systemic vascular resistance resulting in deterioration. The condition, although uncommon, is often associated with a potentially correctable aetiology. In the absence of a remediable cause, therapeutic options are very limited but include dietary restriction of salt and water combined with judicious use of diuretics. Vasodilators and beta-adrenoceptor positive inotropes are not recommended.