The spatial-temporal dynamics of pulmonary blood flow are altered in pulmonary arterial hypertension

Global fluctuation dispersion (FDglobal), a spatial-temporal metric derived from serial images of the pulmonary perfusion obtained with MRI-arterial spin labeling, describes temporal fluctuations in the spatial distribution of perfusion. In healthy subjects, FDglobal is increased by hyperoxia, hypoxia, and inhaled nitric oxide. We evaluated patients with pulmonary arterial hypertension (PAH, 4F, aged 47 ± 15, mean pulmonary artery pressure 48 ± 7 mmHg) and healthy controls (CON, 7F, aged 47 ± 12) to test the hypothesis that FDglobal is increased in PAH. Images were acquired at ∼4-5 s intervals during voluntary respiratory gating, inspected for quality, registered using a deformable registration algorithm, and normalized. Spatial relative dispersion (RD = SD/mean) and the percent of the lung image with no measurable perfusion signal (%NMP) were also assessed. FDglobal was significantly increased in PAH (PAH = 0.40 ± 0.17, CON = 0.17 ± 0.02, P = 0.006, a 135% increase) with no overlap in values between the two groups, consistent with altered vascular regulation. Both spatial RD and %NMP were also markedly greater in PAH vs. CON (PAH RD = 1.46 ± 0.24, CON = 0.90 ± 0.10, P = 0.0004; PAH NMP = 13.4 ± 6.1%; CON = 2.3 ± 1.4%, P = 0.001 respectively) consistent with vascular remodeling resulting in poorly perfused regions of lung and increased spatial heterogeneity. The difference in FDglobal between normal subjects and patients with PAH in this small cohort suggests that spatial-temporal imaging of perfusion may be useful in the evaluation of patients with PAH. Since this MR imaging technique uses no injected contrast agents and has no ionizing radiation it may be suitable for use in diverse patient populations.NEW & NOTEWORTHY Using proton MRI-arterial spin labeling to obtain serial images of pulmonary perfusion, we show that global fluctuation dispersion (FDglobal), a metric of temporal fluctuations in the spatial distribution of perfusion, was significantly increased in female patients with pulmonary arterial hypertension (PAH) compared with healthy controls. This potentially indicates pulmonary vascular dysregulation. Dynamic measures using proton MRI may provide new tools for evaluating individuals at risk of PAH or for monitoring therapy in patients with PAH.

Evidence of region-specific right ventricular functional adaptation in endurance-trained men in response to an acute volume infusion

NEW FINDINGS

What is the central question of this study? Endurance athletes demonstrate altered regional right ventricular (RV) wall mechanics, characterized by lower basal deformation, in comparison to non-athletic control subjects at rest. We hypothesized that regional adaptations at the RV base reflect an enhanced functional reserve capacity in response to haemodynamic volume loading. What is the main finding and its importance? Free wall RV longitudinal strain is elevated in response to acute volume loading in both endurance athletes and control subjects. However, the RV basal segment longitudinal strain response to acute volume infusion is greater in endurance athletes. Our findings suggest that training-induced cardiac remodelling might involve region-specific adaptation in the RV functional response to volume manipulation.

ABSTRACT

Eccentric remodelling of the right ventricle (RV) in response to increased blood volume and repetitive haemodynamic load during endurance exercise is well established. Structural remodelling is accompanied by decreased deformation at the base of the RV free wall, which might reflect an enhanced functional reserve capacity in response to haemodynamic perturbation. Therefore, in this study we examined the impact of acute blood volume expansion on RV wall mechanics in 16 young endurance-trained men (aged 24 ± 3 years) and 13 non-athletic male control subjects (aged 27 ± 5 years). Conventional echocardiographic parameters and the longitudinal strain and strain rate were quantified at the basal and apical levels of the RV free wall. Measurements were obtained at rest and after 7 ml/kg i.v. Gelofusine infusion, with and without a passive leg raise. After infusion, blood volume increased by 12 ± 4 and 14 ± 5% in endurance-trained individuals versus control subjects, respectively (P = 0.264). Both endurance-trained individuals (8 ± 10%) and control subjects (7 ± 9%) experienced an increase in free wall strain from baseline, which was also similar following leg raise (7 ± 10 and 6 ± 10%, respectively; P = 0.464). However, infusion evoked a greater increase in basal longitudinal strain in endurance-trained versus control subjects (16 ± 14 vs. 6 ± 11%; P = 0.048), which persisted after leg raise (16 ± 18 vs. 3 ± 11%; P = 0.032). Apical longitudinal strain and RV free wall strain rates were not different between groups and remained unchanged after infusion across all segments. Endurance training results in a greater contribution of longitudinal myocardial deformation at the base of the RV in response to a haemodynamic volume challenge, which might reflect a greater region-specific functional reserve capacity.

Mildly elevated pulmonary artery systolic pressure on echocardiography: bridging the gap in current guidelines

Pulmonary hypertension is associated with increased morbidity and mortality, and growing evidence suggests that even mild elevations in pulmonary artery pressure estimated with echocardiography are linked to increased mortality. In healthy individuals who undergo right heart catheterisation, the average pulmonary artery systolic pressure ranges from 17 mm Hg to 25 mm Hg; on echocardiography, estimated pulmonary artery systolic pressure of more than 30 mm Hg is outside the normal range for most healthy individuals. Increased pulmonary artery systolic pressure (>30 mm Hg) is reported on more than 40% of clinically indicated echocardiograms, often in the presence of metabolic and cardiopulmonary comorbidities, and is associated with a 5-year mortality of 25-40%. However, current guidelines do not sufficiently highlight risk and risk-reduction approaches for the sizable patient population with elevated pulmonary artery pressure who do not have underlying severe pulmonary vascular disease such as pulmonary arterial hypertension. Increased awareness of this frequently reported high-risk echocardiographic finding, and multidisciplinary risk-reduction approaches for patients with metabolic and cardiopulmonary comorbidities and elevated pulmonary artery pressure, are urgently needed.

Right Ventricular Function and Region-Specific Adaptation in Athletes Engaged in High-Dynamic Sports: A Meta-Analysis

BACKGROUND

Structural remodeling of the right ventricle (RV) is widely documented in athletes. However, functional adaptation, including RV pressure generation and systolic free-wall longitudinal mechanics, remains equivocal. This meta-analysis compared RV pressure and function in athletes and controls.

METHODS

A systematic review of online databases was conducted up to June 4, 2020. Meta-analyses were performed on RV systolic pressures, at rest and during exercise, tricuspid annular plane systolic displacement, myocardial velocity (S'), and global and regional longitudinal strain. Bias was assessed using Egger regression for asymmetry. Data were analyzed using random-effects models with weighted mean difference and 95% CI.

RESULTS

Fifty-three studies were eligible for inclusion. RV systolic pressure was obtained from 21 studies at rest (n=1043:1651; controls:athletes) and 8 studies during exercise (n=240:495) and was significantly greater in athletes at rest (weighted mean difference, 2.9 mmHg [CI, 1.3-4.5 mmHg]; P=0.0005) and during exercise (11.0 [6.5-15.6 mm Hg]; P<0.0001) versus controls. Resting tricuspid annular plane systolic displacement (P<0.0001) and S' (P=0.001) were greater in athletes. In contrast, athletes had similar RV free-wall longitudinal strain (17 studies; n=450:605), compared with controls but showed greater longitudinal apical strain (16 studies; n=455:669; 0.9%, 0.1%-1.8%; P=0.03) and lower basal strain (-2.5% [-1.4 to -3.5%]; P<0.0001).

CONCLUSIONS

Functional RV adaptation, characterized by increased tricuspid annular displacement and velocity and a greater base-to-apex strain gradient, is a normal feature of the athlete's heart, together with a slightly elevated RV systolic pressure. These findings contribute to our understanding of RV in athletes and highlight the importance of considering RV function in combination with structure in the clinical interpretation of the athlete's heart.

Left Ventricular Fibrosis in Middle-Age Athletes and Physically Active Adults

INTRODUCTION

Cardiac magnetic resonance (CMR) late gadolinium enhancement (LGE) and T1 mapping techniques enable the quantification of focal and diffuse myocardial LGE, respectively. Studies have shown evidence of fibrosis in middle-age athletes, but not relative to physically active (PA) adults who perform recommended physical activity levels. Therefore, we examined cardiac remodeling and presence of left ventricular (LV) LGE and T1 values in both recreational middle-age endurance athletes (EA) and PA adults.

METHODS

Healthy EA and PA adults (45-65 yr) completed a standardized 3-T CMR protocol with ventricular volumetry, LV LGE, and T1 mapping.

RESULTS

Seventy-two EA and 20 PA participants (mean age, 53 ± 5 vs 56 ± 4 yr; P < 0.01; V˙O2peak = 50 ± 7 vs 37 ± 9 mL·kg·min, P < 0.0001) were examined, with CMR data available in 89/92 participants. Focal LV LGE was observed in 30% of participants (n = 27/89): 33% of EA (n = 23/69; 33%) and 20% of PA (n = 4/20; 20%). LGE was present at the right ventricular hinge point (n = 21/89; 23.5%) or identified as ischemic (n = 2/89; 2%) or nonischemic (n = 4/89; 4%). Focal LV LGE was observed similarly in both EA and PA (P = 0.25). EA had larger LV chamber sizes and T1 native values (1169 ± 35 vs 1190 ± 26, P = 0.02) compared with PA, with similar LV ejection fraction. Global extracellular volume (ECV) was similar in both EA and PA (22.6% ± 3.5% vs 21.5% ± 2.6%, P = 0.26), with no relationship between global ECV and LV mass (r = -0.16, P = 0.19).

CONCLUSIONS

Focal LGE at the right ventricular hinge point was detected at the same frequency in both groups, was unrelated to demographic or clinical indices, and was found without evidence of global ECV expansion in EA, suggesting a physiologic remodeling response. The long-term clinical implications of hinge-point LGE require clarification using prospective, long-term follow-up studies.

Update on noninvasive imaging of right ventricle dysfunction in pulmonary hypertension

Pulmonary hypertension (PH) is a progressive disease affecting patients across the life span. The pathophysiology primarily involves the pulmonary vasculature and right ventricle (RV), but eventually affects the left ventricular (LV) function as well. Safe, accurate imaging modalities are critical for diagnosis, serial monitoring, and tailored therapy. While cardiac catheterization remains the conventional modality for establishing diagnosis and serial monitoring, noninvasive imaging has gained considerable momentum in providing accurate assessment of the entire RV-pulmonary axis. In this state-of-the-art review, we will discuss the most recent developments in echocardiography, magnetic resonance imaging, and computed tomography in PH evaluation from pediatric to adult population.

The importance of ST elevation in V2-4 ECG leads in athletes

BACKGROUND

Early repolarization in the anterior ECG leads (ERV_2-4) is considered to be a sign of right ventricular (RV) remodeling, but its etiology and importance are unclear.

METHODS

A total of 243 top-level endurance-trained athletes (ETA; 183 men and 60 women, weekly training hours: 15-20) and 120 leisure-time athletes (LTA; 71 men and 49 women, weekly training hours: 5-6) were investigated. The ERV_2-4 sign was evaluated concerning type of sport, gender, transthoracic echocardiographic parameters, and ECG changes, which can indicate elevated RV systolic pressure [left atrium enlargement (LAE), right atrium enlargement (RAE), RV conduction defect (RVcd)].

RESULTS

Stroke volume and left ventricular mass were higher in ETAs vs. LTAs in both genders (p < 0.01). Prevalence of the ERV_2-4 sign was significantly higher in men than in women [p = 0.000, odds ratio (OR) = 36.4] and in ETAs than in LTAs (p = 0.000). The highest ERV_2-4 prevalence appeared in the most highly trained triathlonists and canoe and kayak paddlers (OR = 13.8 and 5.2, respectively). Within the ETA group, the post-exercise LAE, RAE, and RVcd changes developed more frequently in cases with than without ERV_2-4 (LAE: men: p < 0.05, females: p < 0.005; RAE: men: p < 0.05, females: p < 0.005; RVcd: N.S.). These post-exercise appearing LAE, RAE, and RVcd are associated with the ERV_2-4 sign (OR = 4.0, 3.7, and 3.8, respectively).

CONCLUSIONS

According to these results, ERV_2-4 develops mainly in male ETAs due to long-lasting and repeated endurance training. The ERV_2-4 sign indicates RV's adaptation to maintain higher compensatory pulmonary pressure and flow during exercise but its danger regarding malignant arrhythmias is unclear.

Pulmonary hypertension subjects exhibit right ventricular transient exertional dilation during supine exercise stress echocardiography

Pulmonary hypertension is a condition with high morbidity and mortality. Resting transthoracic echocardiography is a pivotal diagnostic and screening test for pulmonary hypertension. The role of exercise stress echocardiography in the diagnosis of pulmonary hypertension is not well-established. We studied right ventricular size changes during exercise using exercise stress echocardiography to assess differences between normal and pulmonary hypertension patients and evaluate test safety, feasibility, and reproducibility. Healthy control and pulmonary hypertension patients performed recumbent exercise using a bicycle ergometer. Experienced echocardiography sonographers recorded the following resting and peak exercise right ventricular parameters using the apical four chamber view: end-diastolic area; end-systolic area; mid-diameter; basal diameter; and longitudinal diameter. Two cardiologists masked to clinical information subsequently analyzed the recordings. Parameters with acceptable inter-rater reliability were analyzed for statistical differences between the normal and pulmonary hypertension patient groups and their association with pulmonary hypertension. We enrolled 38 healthy controls and 40 pulmonary hypertension patients. Exercise stress echocardiography testing was found to be safe and feasible. Right ventricular size parameters were all readily obtainable and all had acceptable inter-observer reliability except for right ventricular longitudinal diameter. During exercise, healthy controls demonstrated a decrease in right ventricular end-systolic area, end-diastolic area, mid-diameter, and basal diameter (P < 0.05). Conversely, pulmonary hypertension patients demonstrated an increase in right ventricular end-systolic area, end-diastolic area, and mid-diameter (P < 0.05). These changes were unaffected by multivariate corrections. The sensitivity for pulmonary hypertension of an increase in right ventricular size was 97.2% with a negative predictive value of 95.2%. The ROC C-statistic for increase in right ventricular size was 0.93. This transient exertional dilation (TED) of the right ventricle is observed in pulmonary hypertension patients but not in healthy controls. Recumbent right ventricular exercise stress echocardiography is a feasible and safe diagnostic test for pulmonary hypertension which warrants additional study.

State-of-the-Art Review: Echocardiography in Pulmonary Hypertension

Pulmonary hypertension is a progressive and often fatal disease that frequently presents with dyspnoea on exertion and results in increased right ventricular afterload and right ventricular failure. Although cardiac catheterisation is required for a formal diagnosis, transthoracic echocardiography (TTE) has a central role as a screening tool in those with symptoms and those at risk for developing pulmonary vascular disease. Echocardiographic techniques can be employed to estimate pulmonary artery pressure and resistance, right atrial pressure as well as to derive indirect information about right heart structure and function. Potential causes for pulmonary hypertension may also be identified such as congenital heart disease or left ventricular diastolic dysfunction. An increasing body of evidence has demonstrated the important prognostic utility of echocardiographic data in pulmonary hypertension and highlighted the potential for TTE to help clinicians understand whether treatment responses have been adequate or an escalation in therapy is necessary, as therapeutic options continue to expand for patients with pulmonary arterial hypertension. Although traditional echocardiographic techniques only allow surrogate measures of right ventricular systolic function due to the complex shape of the chamber, newer techniques have enabled three-dimensional assessment of the right ventricle to assess right ventricular volume and contractility. This review will discuss traditional methods as well as newer echocardiographic methods in the setting of pulmonary hypertension.

The Right Heart International Network (RIGHT-NET): Rationale, Objectives, Methodology, and Clinical Implications

The Right Heart International Network is a multicenter international study aiming to prospectively collect exercise Doppler echocardiography tests of the right heart pulmonary circulation unit (RHPCU) in large cohorts of healthy subjects, elite athletes, and individuals at risk of or with overt pulmonary hypertension. It is going to provide standardization of exercise stress echocardiography of RHPCU and explore the full physiopathologic response.

Exercise and the right ventricle: a potential Achilles' heel

Exercise is associated with unequivocal health benefits and results in many structural and functional changes of the myocardium that enhance performance and prevent heart failure. However, intense exercise also presents a significant hemodynamic challenge in which the right-sided heart chambers are exposed to a disproportionate increase in afterload and wall stress that can manifest as myocardial fatigue or even damage if intense exercise is sustained for prolonged periods. This review focuses on the physiological factors that result in a disproportionate load on the right ventricle during exercise and the long-term consequences. The changes in cardiac structure and function that define 'athlete's heart' disproportionately affect the right-sided heart chambers and this can raise important diagnostic overlap with some cardiac pathologies, particularly some inherited cardiomyopathies. The interaction between exercise and arrhythmogenic right ventricular cardiomyopathy (ARVC) will be highlighted as an important example of how hemodynamic stressors can combine with deficiencies in cardiac structural elements to cause cardiac dysfunction predisposing to arrhythmias. The extent to which extreme exercise can cause adverse remodelling in the absence of a genetic predisposition remains controversial. In the athlete with profound changes in heart structure, it can be extremely challenging to determine whether common symptoms such as palpitations may be a marker of more sinister arrhythmias. This review discusses some of the techniques that have recently been proposed to identify pathology in these circumstances. Finally, we will discuss recent evidence defining the role of exercise restriction as a therapeutic intervention in individuals predisposed to arrhythmogenic cardiomyopathy.

Enhanced Right-Chamber Remodeling in Endurance Ultra-Trail Athletes Compared to Marathon Runners Detected by Standard and Speckle-Tracking Echocardiography

Background: Strenuous and endurance exercise training have been associated with morphological and functional heart remodeling. Two-dimensional speckle-tracking echocardiography (STE) is a novel technique that allows an accurate quantification of global myocardium deformation. Our aim was to evaluate together left and right cardiac remodeling in different long-distance running athletes: marathon runners (42 km) (M) and endurance mountain runners (>300 Km) (UT).

Methods: A total of 92 athletes (70 males, 76%) including 47 M [age 45 ± 7 years; training: 18 (9–53) years^*days/week], 45 UT [age 42 ± 9, training: 30 (15–66) years^*days/week] underwent conventional echocardiography and STE (Beyond Diogenes 2.0, AMID) during the agonistic season.

Results: Right ventricle (RV) end-diastolic area (p = 0.026), fractional area changing (FAC) (p = 0.008) and RV global longitudinal strain (GLS) were significantly increasedin UT athletes. Furthermore, UT showed larger right atrium (RA) volume (p = 0.03), reduced RA GLS and significantly increased RA global circumferential strain (GCS) compared to M. After adjustment for age, sex, and HR as covariates, UT showed a reduced RA GLS (OR 0.907; CI 0.856–0.961) and increased RV FAC (OR 1.172; CI: 1.044–1.317) compared to M.

Conclusion: Athletes enrolled in UT endurance activities showed RV and RA morphological and functional remodeling to increased preload in comparison with M runners characterized by increased RV FAC and reduced RA GLS. Follow-up studies are needed to better assess the long-term clinical impact of these modifications. 2D STE is a useful tool for investigating the deformation dynamic in different sports specialties.

The impact of age and gender on right ventricular diastolic function among healthy adults

BACKGROUND

Doppler echocardiography is ideally suited for assessment of diastolic function, being widely available, non-invasive, and less expensive than other techniques. However, data regarding age- and gender-matched reference values of right ventricular diastolic function are limited. This study aims to explore the physiologic variations of right ventricle (RV) diastolic function in a large cohort of healthy adults, and to investigate clinical and echocardiographic correlates.

METHODS

From June 2007 to February 2014, 1168 healthy Caucasian subjects [mean age 45.1±15.6 years, range 16-92; 555 (47.5%) men] underwent comprehensive transthoracic echocardiography (TTE) following current guidelines. The following RV main diastolic measurements were measured: peak early inflow velocity (E), annular both early (e') and atrial (a') velocities, E/e' ratio.

RESULTS

RV E/e' constantly increases with age in females, but do not change substantially in males. RV E/A constantly decreases with age in both genders. Stepwise multiple linear regression analysis underlined a close significant association of RV diastolic function with both right and left heart morphologic measurements (right atrial area, RV diameters, left atrial volume) and functional indexes (TAPSE, RV tissue Doppler peak systolic velocity, left ventricular E/Ee'), as well as with indexes of increased pulmonary resistance.

CONCLUSION

Our data highlight the potential usefulness of different normal reference values according to the age and gender to correctly evaluate RV diastolic function. Differences in terms of demographic and anthropometric parameters could be useful to avoid potential misclassification of RV diastolic function when based on dichotomously suggested normal cut-off values.

Influence of gender on right ventricle adaptation to endurance exercise: an ultrasound two-dimensional speckle-tracking stress study

BACKGROUND

Characteristic right ventricle (RV) remodelling is related to endurance exercise in male athletes (MAs), but data in female athletes (FAs) are scarce. Our aim was to evaluate sex-related influence on exercise-induced RV remodelling and on RV performance during exercise.

METHODS

Forty endurance athletes (>10 training hours/week, 50% female) and 40 age-matched controls (<3 h moderate exercise/week, 50% female) were included. Echocardiography was performed at rest and at maximum cycle-ergometer effort. Both ventricles were analysed by standard and speckle-tracking echocardiography.

RESULTS

Endurance training induced similar structural and functional cardiac remodelling in MAs and FAs, characterized by bi-ventricular dilatation [~34%, left ventricle (LV); 29%, RV] and normal bi-ventricular function. However, males had larger RV size (p < 0.01), compared to females: RV end-diastolic area (cm²/m²): 15.6 ± 2.2 vs 11.6 ± 1.7 in athletes; 12.2 ± 2.7 vs 8.6 ± 1.6 in controls, respectively, and lower bi-ventricular deformation (RV global longitudinal strain (GLS) (%): -24.0 ± 3.6 vs -29.2 ± 3.1 in athletes; -24.9 ± 2.5 vs -30.0 ± 1.9 in controls, and LVGLS: -17.5 ± 1.4 vs -21.9 ± 1.9 in athletes; -18.7 ± 1.2 vs -22.5 ± 1.5 in controls, respectively, p < 0.01). During exercise, the increase in LV function was positively correlated (p < 0.01) with increased cardiac output (∆%LV ejection fraction, r = +0.46 and ∆%LVGLS, r = +0.36). Improvement in RV performance was blunted at high workloads, especially in MAs.

CONCLUSION

Long-term endurance training induced similar bi-ventricular remodelling in MAs and FAs. Independently of training load, males had larger RV size and lower bi-ventricular deformation. Improvement in RV performance during exercise was blunted at high workloads, especially in MAs. The potential mechanisms underlying these findings warrant further investigation.

Acute and Chronic Response to Exercise in Athletes: The "Supernormal Heart"

During last decades, most studies have examined the exercise-induced remodeling defined as "athlete's heart". During exercise, there is an increased cardiac output that causes morphological, functional, and electrical modification of the cardiac chambers. The cardiac remodeling depends also on the type of training, age, sex, ethnicity, genetic factors, and body size. The two main categories of exercise, endurance and strength, determine different effects on the cardiac remodeling. Even if most sport comprise both strength and endurance exercise, determining different scenarios of cardiac adaptation to the exercise. The aim of this paper is to assemble the current knowledge about physiologic and pathophysiologic response of both the left and the right heart in highly trained athletes.

The multi-modality cardiac imaging approach to the Athlete's heart: an expert consensus of the European Association of Cardiovascular Imaging

The term 'athlete's heart' refers to a clinical picture characterized by a slow heart rate and enlargement of the heart. A multi-modality imaging approach to the athlete's heart aims to differentiate physiological changes due to intensive training in the athlete's heart from serious cardiac diseases with similar morphological features. Imaging assessment of the athlete's heart should begin with a thorough echocardiographic examination.Left ventricular (LV) wall thickness by echocardiography can contribute to the distinction between athlete's LV hypertrophy and hypertrophic cardiomyopathy (HCM). LV end-diastolic diameter becomes larger (>55 mm) than the normal limits only in end-stage HCM patients when the LV ejection fraction is <50%. Patients with HCM also show early impairment of LV diastolic function, whereas athletes have normal diastolic function.When echocardiography cannot provide a clear differential diagnosis, cardiac magnetic resonance (CMR) imaging should be performed.With CMR, accurate morphological and functional assessment can be made. Tissue characterization by late gadolinium enhancement may show a distinctive, non-ischaemic pattern in HCM and a variety of other myocardial conditions such as idiopathic dilated cardiomyopathy or myocarditis. The work-up of athletes with suspected coronary artery disease should start with an exercise ECG. In athletes with inconclusive exercise ECG results, exercise stress echocardiography should be considered. Nuclear cardiology techniques, coronary cardiac tomography (CCT) and/or CMR may be performed in selected cases. Owing to radiation exposure and the young age of most athletes, the use of CCT and nuclear cardiology techniques should be restricted to athletes with unclear stress echocardiography or CMR.

Physiologic and pathophysiologic changes in the right heart in highly trained athletes

Exercise causes changes in the heart in response to the hemodynamic demands of increased systemic and pulmonary requirements during exercise. Understanding these adaptations is of great importance, since they may overlap with those caused by pathological conditions. Initial descriptions of athlete's heart focused mainly on chronic adaptation of the left heart to training. In recent years, the substantial structural and functional adaptations of the right heart have been documented, highlighting the complex interplay with left heart. Moreover, there is evolving evidence of acute and chronic cardiac damage, mainly involving the right heart, which may predispose subjects to atrial and ventricular arrhythmias, configuring an exercise-induced cardiomyopathy. The aim of this article is to review the current knowledge on the physiologic and pathophysiologic changes in the right heart in highly trained athletes.

Protocol for exercise hemodynamic assessment: performing an invasive cardiopulmonary exercise test in clinical practice

Invasive cardiopulmonary exercise testing (iCPET) combines full central hemodynamic assessment with continuous measurements of pulmonary gas exchange and ventilation to help in understanding the pathophysiology underpinning unexplained exertional intolerance. There is increasing evidence to support the use of iCPET as a key methodology for diagnosing heart failure with preserved ejection fraction and exercise-induced pulmonary hypertension as occult causes of exercise limitation, but there is little information available outlining the methodology to use this diagnostic test in clinical practice. To bridge this knowledge gap, the operational protocol for iCPET at our institution is discussed in detail. In turn, a standardized iCPET protocol may provide a common framework to describe the evolving understanding of mechanism(s) that limit exercise capacity and to facilitate research efforts to define novel treatments in these patients.

Essential echocardiographic evaluation in patients with suspected pulmonary hypertension: an overview for the practicing physician

Prompt and accurate diagnosis of patients presenting with symptoms suggestive of pulmonary arterial hypertension (PAH) is of outmost importance as delays in identifying this clinical entity have detrimental effects on both morbidity and mortality. Initial noninvasive assessment of these patients has traditionally included a number of routine tests of which transthoracic echocardiography (TTE) has been shown to either confirm the presence of structural anomalies of the right ventricle (RV) indicative of PAH or exclude other potential causes of pulmonary hypertension (PH). Consequently, TTE has become a well-validated and readily available imaging tool not only used for this initial screening but also for routine follow-up of PH patients. Since chronic PH is known to unbalance the normal hemodynamic and mechanical homeostatic interaction between the RV and pulmonary circulation; the resulting response is that of an abnormal RV remodeling, clinically translated into progressive RV hypertrophy and dilatation. An enlarged and hypertrophied RV not only would eventually lose effective contractility but also this gradual decline in RV systolic function is the main abnormality in determining adverse clinical outcomes. Therefore, it is of outmost importance that TTE examination be comprehensive but most importantly accurate and reproducible. This review aims to highlight the most important objective measures that can be routinely employed, without added complexity, that will certainly enhance the interpretation and advance our understanding of the hemodynamic and mechanical abnormalities that PH exerts on the RV.

The role of new echocardiographic techniques in athlete's heart

‘Athlete’s heart’ is a common term for the various adaptive changes induced by intensive exercise. Exercise causes alterations of the heart in hemodynamic response to the increased systemic and pulmonary demand during exercise. The understanding of these adaptations is of high importance, since they may overlap with those caused by pathological conditions. Cardiac imaging assessment of the athlete’s heart should begin with a complete echocardiographic examination. In recent years classical echocardiographic surveys have been joined by new developments: tissue Doppler imaging, strain rate echocardiography, and real-time 3-dimensional echocardiography. This review paper focuses on the importance of these new echocardiographic techniques in delineating the morphological characteristics and functional properties of the athlete’s heart.

An investigation into the relationship between age and physiological function in highly active older adults

KEY POINTS

The relationship between age and physiological function remains poorly defined and there are no physiological markers that can be used to reliably predict the age of an individual. This could be due to a variety of confounding genetic and lifestyle factors, and in particular to ill-defined and low levels of physical activity. This study assessed the relationship between age and a diverse range of physiological functions in a cohort of highly active older individuals (cyclists) aged 55-79 years in whom the effects of lifestyle factors would be ameliorated. Significant associations between age and function were observed for many functions. V̇O2max was most closely associated with age, but even here the variance in age for any given level was high, precluding the clear identification of the age of any individual. The data suggest that the relationship between human ageing and physiological function is highly individualistic and modified by inactivity.

ABSTRACT

Despite extensive research, the relationship between age and physiological function remains poorly characterised and there are currently no reliable markers of human ageing. This is probably due to a number of confounding factors, particularly in studies of a cross-sectional nature. These include inter-subject genetic variation, as well as inter-generational differences in nutrition, healthcare and insufficient levels of physical activity as well as other environmental factors. We have studied a cohort of highly and homogeneously active older male (n = 84) and female (n = 41) cyclists aged 55-79 years who it is proposed represent a model for the study of human ageing free from the majority of confounding factors, especially inactivity. The aim of the study was to identify physiological markers of ageing by assessing the relationship between function and age across a wide range of indices. Each participant underwent a detailed physiological profiling which included measures of cardiovascular, respiratory, neuromuscular, metabolic, endocrine and cognitive functions, bone strength, and health and well-being. Significant associations between age and function were observed for many functions. The maximal rate of oxygen consumption (V̇O2max) showed the closest association with age (r = -0.443 to -0.664; P < 0.001), but even here the variance in age for any given level was high, precluding the clear identification of the age of any individual. The results of this cross-sectional study suggest that even when many confounding variables are removed the relationship between function and healthy ageing is complex and likely to be highly individualistic and that physical activity levels must be taken into account in ageing studies.

Right Ventricular Changes in Highly Trained Athletes: Between Physiology and Pathophysiology

Several studies have described the adaptive remodeling of the heart during exercise. In some more practiced endurance athletes, there is a disproportionate load on the right ventricle (RV), at least during exercise, and this might be the basis for a chronic pro-arrhythmic RV remodeling. Especially, in these kinds of athletes the recovery after detraining might be incomplete, in particular for RV changes. The observation of acute myocardial injury based on transient elevation of biomarkers and chronic myocardial scar, not completely reversible changes of the RV and an increased prevalence of some arrhythmias support the existence of an “exercise-induced cardiomyopathy.” The aim of this paper is to review current knowledge about changes in the right heart in highly trained athletes and how these change influence cardiac function.

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.

Usefulness of echocardiography in preparticipation screening of competitive athletes

INTRODUCTION AND OBJECTIVES

Despite the established diagnostic value of the electrocardiogram in preparticipation screening of athletes, some cardiac structural changes can be missed, particularly in early disease stages. The aim of this study was to evaluate the prevalence of cardiac structural changes via the systematic use of echocardiography in preparticipation screening of competitive athletes.

METHODS

Professional athletes or participants in a competitive athletic program underwent a screening that included family and personal medical history, physical examination, electrocardiography, exercise testing, and Doppler echocardiography.

RESULTS

A total of 2688 athletes (67% men; mean age [standard deviation], 21 [10] years) were included. Most of the echocardiographic evaluations (92.5%) were normal and only 203 (7.5%) showed changes; the most frequent change was left ventricular hypertrophy, seen in 50 athletes (1.8%). Cessation of athletic activity was indicated in 4 athletes (0.14%): 2 for hypertrophic cardiomyopathy (electrocardiography had shown changes that did not meet diagnostic criteria), 1 pectus excavatum with compression of the right ventricle, and 1 significant pulmonary valve stenosis; the rest of the changes did not entail cessation of athletic activity and only indicated periodic monitoring.

CONCLUSIONS

Although rare, some cardiac structural changes can be missed on physical examination and electrocardiography; in contrast, they are easily recognized with echocardiography. These findings suggest the use of echocardiography in at least the first preparticipation screening of competitive athletes to improve the effectiveness of programs aimed at preventing sudden death in athletes.

Right heart adaptation to pulmonary arterial hypertension: physiology and pathobiology

Survival in patients with pulmonary arterial hypertension (PAH) is closely related to right ventricular (RV) function. Although pulmonary load is an important determinant of RV systolic function in PAH, there remains a significant variability in RV adaptation to pulmonary hypertension. In this report, the authors discuss the emerging concepts of right heart pathobiology in PAH. More specifically, the discussion focuses on the following questions. 1) How is right heart failure syndrome best defined? 2) What are the underlying molecular mechanisms of the failing right ventricle in PAH? 3) How are RV contractility and function and their prognostic implications best assessed? 4) What is the role of targeted RV therapy? Throughout the report, the authors highlight differences between right and left heart failure and outline key areas of future investigation.

Morphological and Functional Adaptation of Left and Right Atria Induced by Training in Highly Trained Female Athletes

Background—

Exercise is able to induce atrial remodeling in top-level athletes. However, evidence is mainly limited to men and based on cross-sectional studies. The aim of this prospective, longitudinal study was to investigate whether exercise is able to influence left and right atrial morphology and function also in female athletes.

Methods and Results—

Two-dimensional echocardiography was performed before season and after 16 weeks of intensive training in 24 top-level female athletes. Left and right atrial myocardial deformation was assessed by two-dimensional speckle-tracking echocardiography. Left atrial volume index (24.0±3.6 versus 26.7±6.9 mL/m 2 ; P <0.001) and right atrial volume index (15.66±3.09 versus 20.47±4.82 mL/m 2 ; P <0.001) significantly increased after training in female athletes. Left atrial global peak atrial longitudinal strain and peak atrial contraction strain significantly decreased after training in female athletes (43.9±9.5% versus 39.8±6.5%; P <0.05 and 15.5±4.0% versus 13.9±4.0%; P <0.05, respectively). Right atrial peak atrial longitudinal strain and peak atrial contraction strain showed a similar, although non-significant decrease (42.8±10.6% versus 39.3±8.3%; 15.6±5.6% versus 13.1±6.1%, respectively). Neither biventricular E / e ′ ratio nor biatrial stiffness changed after training, suggesting that biatrial remodeling occurs in a model of volume rather than pressure overload.

Conclusions—

Exercise is able to induce biatrial morphological and functional changes in female athletes. Biatrial enlargement, with normal filling pressures and low atrial stiffness, is a typical feature of the heart of female athletes. These findings should be interpreted as physiological adaptations to exercise and should be considered in the differential diagnosis with cardiomyopathies.

Effect of inhaled iloprost on the exercise function of Fontan patients: a demonstration of concept

BACKGROUND

Exercise capacity following Fontan surgery is often depressed. An inability to reduce pulmonary vascular resistance appropriately during exercise may contribute to this phenomenon. The aim of this study was to determine whether administration of iloprost, a selective pulmonary vasodilator, would improve exercise function after Fontan procedure.

METHODS

Double-blind, randomized, placebo controlled, crossover trial. Patients performed two cardiopulmonary exercise tests (CPX) separated by <1 month. A single nebulizer treatment (iloprost or placebo) was administered before each CPX.

RESULTS

18 patients aged 12-49 (median 17) years were recruited. Mild throat discomfort developed in 10/18 patients during iloprost administration; all but 1 were able to complete treatment. No symptoms developed during placebo treatments (p<0.001). Two additional patients did not complete CPX: one with atrial flutter; another with developmental issues that precluded adequate CPX. In the 15 remaining subjects oxygen pulse (a surrogate for forward stroke volume) at peak exercise was higher following iloprost (median increase 1.2 ml/beat; p<0.001). Peak VO2 also rose (median increase 1.3 ml/kg/min; p<0.04). Nine patients had peak VO2 <30 ml/kg/min; each of these patients had higher peak VO2 following iloprost. Only 3/6 patients with peak VO2 >30 ml/kg/min had higher peak VO2 following iloprost (p<0.04).

CONCLUSIONS

Iloprost improves the peak oxygen pulse and peak VO2 of patients with Fontan physiology and appears to be particularly beneficial among patients with impaired exercise function. Treatment is associated with minor side effects. These findings support the concept of pulmonary vasodilator therapy in Fontan patients with limited functional capacity.

Exercise stress echocardiography of the pulmonary circulation: limits of normal and sex differences

BACKGROUND

Exercise stress echocardiography has not been recommended in the diagnostic workup of pulmonary hypertension because of insufficient certainty about feasibility and limits of normal.

METHODS

Doppler echocardiography pulmonary hemodynamic measurements were performed at a progressively increased workload in 56 healthy male and 57 healthy female volunteers aged 19 to 63 years. Mean pulmonary artery pressure (mPAP) was estimated from the maximal tricuspid regurgitation jet velocity. Cardiac index was calculated from the left ventricular outflow velocity-time integral. Pulmonary vascular distensibility a index, the percentage change of vessel diameter permm Hg of mPAP, was calculated from multipoint mPAP-cardiac output (CO) plots.

RESULTS

Peak exercise at 175 ±50 W was associated with an mPAP of 33±7 mm Hg and a CO of 18 ±5 L/min. The slope of mPAP-CO relationships was 1.5 ± 0.5 mm Hg/L/min, and the distensibility coefficient ( α ) was 1.3%± 1.0%/mm Hg. Maximal workload and cardiac index were higher in men than in women ( P , .05), but mPAP-cardiac index relationships were not different. However,women had a higher a (1.6%± 1.3%/mm Hg vs 1.1%± 0.6%/mm Hg, P < .05). The average mPAP-cardiac index slope was higher and a lower in subjects ≥50 years old. Upper limits of normal of mPAP at exercise were 34 mm Hg at a CO , 10 L/min, 45 mm Hg at a CO <20 L/min, and 52 mm Hg at a CO<30 L/min. These values are in keeping with previously reported invasive measurements.

CONCLUSIONS

Exercise stress echocardiography of the pulmonary circulation is feasible and allows for fl ow-corrected definition of upper limits of normal. Women have a more distensible pulmonary circulation.

Clinical and echocardiographic correlations of exercise-induced pulmonary hypertension in systemic sclerosis: a multicenter study

BACKGROUND

Patients with systemic sclerosis (SSc) are at risk for developing pulmonary hypertension, which is associated with a poor prognosis. Exercise Doppler echocardiography enables the identification of exercise-induced increase in pulmonary artery systolic pressure (PASP) and may provide a thorough noninvasive hemodynamic evaluation.

AIM

The aim of this study was to evaluate the clinical and echocardiographic determinants of exercise-induced increase in PASP in a large population of patients with SSc.

METHODS

We selected 164 patients with SSc (age 58 ± 13 years, 91% female) with normal resting PASP (<40 mm Hg) who underwent a comprehensive 2-dimensional and Doppler echocardiography and graded bicycle semisupine exercise Doppler echocardiography. Pulmonary artery systolic pressure, cardiac output, and pulmonary vascular resistance (PVR) were estimated noninvasively. Cutoff values of PASP ≥50 mm Hg and PVR ≥3.0 Wood Units at peak exercise were considered a significant exercise-induced increase in PASP and PVR, respectively.

RESULTS

Sixty-nine (42%) patients showed a significant exercise-induced increase in PASP. Among them, peak PVR ≥3 Wood Units was present only in 11% of patients, about 5% of the total population. Univariate analysis showed that age, presence of interstitial lung disease, and both right and left diastolic dysfunction are predictors of peak PASP ≥50 mm Hg, but none of these parameters predict elevated peak PVR.

CONCLUSIONS

Exercise-induced increase in PASP occurs in almost one-half of patients with SSc with normal resting PASP. Peak exercise PASP is affected by age, interstitial lung disease, and right and left ventricular diastolic dysfunction and, only in 5% of the patients, is associated with an increase in PVR during exercise, suggesting heterogeneity of the mechanisms underlying exercise-induced pulmonary hypertension in SSc.

Exercise-induced pulmonary hypertension: physiological basis and methodological concerns

Exercise stresses the pulmonary circulation through increases in cardiac output (.Q) and left atrial pressure. Invasive as well as noninvasive studies in healthy volunteers show that the slope of mean pulmonary artery pressure (mPAP)-flow relationships ranges from 0.5 to 3 mm Hg.min.L(-1). The upper limit of normal mPAP at exercise thus approximates 30 mm Hg at a .Q of less than 10 L.min(-1) or a total pulmonary vascular resistance at exercise of less than 3 Wood units. Left atrial pressure increases at exercise with an average upstream transmission to PAP in a close to one-for-one mm Hg fashion. Multipoint PAP-flow relationships are usually described by a linear approximation, but present with a slight curvilinearity, which is explained by resistive vessel distensibility. When mPAP is expressed as a function of oxygen uptake or workload, plateau patterns may be observed in patients with systolic heart failure who cannot further increase .Q at the highest levels of exercise. Exercise has to be dynamic to avoid the increase in systemic vascular resistance and abrupt changes in intrathoracic pressure that occur with resistive exercise and can lead to unpredictable effects on the pulmonary circulation. Postexercise measurements are unreliable because of the rapid return of pulmonary vascular pressures and flows to the baseline resting state. Recent studies suggest that exercise-induced increase in PAP to a mean higher than 30 mm Hg may be associated with dyspnea-fatigue symptomatology.

Angiotensin-converting enzyme I/D gene polymorphism affects early cardiac response to professional training in young footballers

BACKGROUND

The renin-angiotensin-aldosterone system plays a role in physiological and pathological responses of the heart to both static and dynamic exercise. Previous studies showed that the level of angiotensin II is determined by the angiotensin-converting enzyme insertion/deletion (ACE I/D) polymorphism.

AIM

We aimed in this study to determine the effect of ACE I/D gene polymorphism on the extent of functional and structural cardiac changes in response to one year of professional football training in young footballers.

METHODS AND RESULTS

We studied 68 young male football players and a comparable control group. Besides medical history and clinical examination, 12 lead ECG and transthoracic 2D echocardiography examination were performed. Genotyping of ACE was analyzed using PCR-based technique. There was no statistically significant difference in distribution of genotypes among athletes compared with control subjects. D allele showed a graded effect on both EF (73.55, 67.5 and 60.2%, p=0.03) and PASP (37.6, 26.1 and 21.39 mmHg, p=0.02) in DD, ID and II subjects, respectively.

CONCLUSION

Early cardiac changes in young footballers can be affected by ACE I/D polymorphism. There is a summative effect of the D allele in increasing EF and PASP in response to professional football training.

Exercise physiology and pulmonary arterial hypertension

The lungs are the only organ that receives the entire cardiac output with every stroke. The pulmonary circulation is normally a high-flow, low-resistance, low-pressure system that carries blood into the pulmonary microcirculation. In pulmonary artery hypertension (PAH)vascular remodeling contributes to a sustained elevation of pulmonary vascular resistance (PVR) and pulmonary artery pressure (PAP) as a result of vascular remodeling characterized largely by vascular smooth muscle cell proliferation and medial hypertrophy, and endothelial cell proliferation resulting in lumen obliteration. The loss of pulmonary arterial compliance and development of elevated PVR puts an excessive burden on the right ventricle due to the increased workload necessary to overcome the downstream pressure, ultimately leading to right-sided heart failure. The functional status of the pulmonary circulation and the levels of PVR and PAP ultimately determine the outcome of patients with PAH. Study of the pressure-flow relationships in the pulmonary vascular bed will provide an improved appreciation of the pathophysiology of pulmonary hypertension.

Ultrasound in sports medicine: relevance of emerging techniques to clinical care of athletes

The applications of ultrasound in managing the clinical care of athletes have been expanding over the past decade. This review provides an analysis of the research that has been published regarding the use of ultrasound in athletes and focuses on how these emerging techniques can impact the clinical management of athletes by sports medicine physicians. Electronic database literature searches were performed using the subject terms 'ultrasound' and 'athletes' from the years 2003 to 2012. The following databases were searched: PubMed, Web of Science, Cochrane Library, CINAHL, and SPORTDiscus™. The search produced 617 articles in total, with a predominance of articles focused on cardiac and musculoskeletal ultrasound. 266 of the studies involved application of ultrasound in evaluating the cardiovascular properties of athletes, and 151 studies involved musculoskeletal ultrasound. Other applications of ultrasound included abdominal, vascular, bone density and volume status. New techniques in echocardiography have made significant contributions to the understanding of the physiological changes that occur in the athlete's heart in response to the haemodynamic stress associated with different types of activity. The likely application of these techniques will be in managing athletes with hypertrophic cardiomyopathy, and the techniques are near ready for application into clinical practice. These techniques are highly specialized, however, and will require referral to dedicated laboratories to influence the clinical management of athletes. Investigation of aortic root pathology and pulmonary vascular haemodynamics are also emerging, but will require additional studies with larger numbers and outcomes analysis to validate their clinical utility. Some of these techniques are relatively simple, and thus hold the potential to enter clinical management in a point-of-care fashion. Musculoskeletal ultrasound has demonstrated a number of diagnostic and therapeutic techniques applicable to pathology of the shoulder, elbow, wrist, hand, hip, knee and ankle. These techniques have been applied mainly to the management of impingement syndromes, tendinopathies and arthritis. Many of these techniques have been validated and have entered clinical practice, while more recently developed techniques (such as dynamic ultrasound and platelet-rich plasma injections) will require further research to verify efficacy. Research in musculoskeletal ultrasound has also been helpful in identifying risk factors for injury and, thus, serving as a focus for developing interventions. Research in abdominal ultrasound has investigated the potential role of ultrasound imaging in assessing splenomegaly in athletes with mononucleosis, in an attempt to inform decisions and policies regarding return to play. Future research will have to demonstrate a reduction in adverse events in order to justify the application of such a technique into policy. The role of ultrasound in assessing groin pain and abdominal pain in ultraendurance athletes has also been investigated, providing promising areas of focus for the development of treatment interventions and physical therapy. Finally, preliminary research has also identified the role of ultrasound in addressing vascular disease, bone density and volume status in athletes. The potential applications of ultrasound in athletes are broad, and continuing research, including larger outcome studies, will be required to establish the clinical utility of these techniques in the care of athletes.

Assessment of electrocardiography, echocardiography, and heart rate variability in dynamic and static type athletes

Background:

Over the last two decades, morphological cardiac changes induced by athletic conditioning have been of great interest. Therefore, several studies have been orchestrated to delineate electrocardiography (ECG), echocardiography, and heart rate variability (HRV) findings in athletes.

Purpose:

To assess the ECG, echocardiography, and HRV in a group of dynamic and static type athletes.

Methods:

Fifty professional athletes (20 static and 30 dynamic exercise athletes) and 50 healthy nonathletes (control group) were recruited. Standard 12-lead ECG and transthoracic echocardiography was performed on all athletes and the control group. Through echocardiography, variables including left ventricular (LV) end-diastolic/systolic diameter, LV mass, and left atrial volume index were measured. In addition, both the athletes and the control group underwent ECG Holter monitoring for 15 minutes and several parameters related to HRV (time and frequency domain) were recorded.

Results:

The most common ECG abnormalities among the athletes were sinus bradycardia and incomplete right bundle branch block. LV end-diastolic diameter and left atrial volume index were significantly greater in the dynamic athletes (P < 0.001). LV end-systolic diameter was significantly lower in the static group (P < 0.001). LV mass of the dynamic and static athletes was significantly greater than that of the controls (P < 0.001). Among the ECG Holter monitoring findings, the dynamic athletes had lower systolic blood pressure than the controls (P = 0.01). Heart rate was lowest in the control group (P < 0.001).

Conclusion:

The most common ECG abnormalities among adolescent Iranian athletes were sinus bradycardia and incomplete right bundle branch block. Static exercise seemed to reduce LV end-systolic diameter, while dynamic exercise resulted in increased LV end-diastolic diameter and left atrial volume index. Additionally, Iranian athletes showed no differences in HRV parameters, excluding heart rate and systolic blood pressure, compared with the nonathletes.

Range of right heart measurements in top-level athletes: the training impact

OBJECTIVES

To explore the full range of right heart dimensions and the impact of long-term intensive training in athletes.

BACKGROUND

Although echocardiography has been widely used to distinguish the athlete's heart from pathologic left ventricular (LV) hypertrophy, only few reports have described right ventricular (RV) and right atrial (RA) adaptations to extensive physical exercise.

METHODS

650 top-level athletes [395 endurance- (ATE) and 255 strength-trained (ATS); 410 males (63.1%); mean age 28.4 ± 10.1; 18-40 years] and 230 healthy age- and sex-comparable controls underwent a transthoracic echocardiographic exam. Along with left heart parameters, right heart measurements included: RV end-diastolic diameters at the basal and mid-cavity level; RV base-to-apex length; RV proximal and distal outflow tract diameters; RA long and short diameters; and RA area. Tricuspid annular plane systolic excursion and RV tissue Doppler systolic peak velocity were assessed as indexes of RV systolic function. Pulmonary artery systolic pressure (PASP) was estimated from the peak tricuspid regurgitant velocity.

RESULTS

ATS showed increased sum of wall thickness and relative wall thickness, whereas left atrial volume, LV end-diastolic volume, LV stroke volume and PASP were significantly higher in ATE. RV and RA measurements were all significantly greater in ATE than in ATS and controls. ATE also showed improved early diastolic RV function, whereas RV systolic indexes were comparable among groups. On multivariate analysis, type and duration of training (p<0.01), PASP (p<0.01) and LV stroke volume (p<0.001) were the only independent predictors of the main RV and RA dimensions in athletes.

CONCLUSIONS

This study delineates the upper limits of RV and RA dimensions in highly-trained athletes. Right heart measurements were all significantly greater in elite endurance-trained athletes than in age- and sex-matched strength athletes and controls. This should be considered as a "physiologic phenomenon" when evaluating athletes for sports eligibility.