Right Heart Structural and Functional Remodeling in Athletes

What echocardiographic findings differentiate acute pulmonary embolism and chronic pulmonary hypertension?

BACKGROUND

Pulmonary embolism (PE) and pulmonary hypertension (PH) are potentially fatal disease states. Early diagnosis and goal-directed management improve outcomes and survival. Both conditions share several echocardiographic findings of right ventricular dysfunction. This can inadvertently lead to incorrect diagnosis, inappropriate and potentially harmful management, and delay in time-sensitive therapies. Fortunately, bedside echocardiography imparts a few critical distinctions.

OBJECTIVE

This narrative review describes eight physiologically interdependent echocardiographic parameters that help distinguish acute PE and chronic PH. The manuscript details each finding along with associated pathophysiology and summarization of the literature evaluating diagnostic utility. This guide then provides pearls and pitfalls with high-quality media for the bedside evaluation.

DISCUSSION

The echocardiographic parameters suggesting acute or chronic right ventricular dysfunction (best used in combination) are: 1. Right heart thrombus (acute PE) 2. Right ventricular free wall thickness (acute ≤ 5 mm, chronic > 5 mm) 3. Tricuspid regurgitation pressure gradient (acute ≤ 46 mmHg, chronic > 46 mmHg, corresponding to tricuspid regurgitation maximal velocity ≤ 3.4 m/sec and > 3.4 m/sec, respectively) 4. Pulmonary artery acceleration time (acute ≤ 60-80 msec, chronic < 105 msec) 5. 60/60 sign (acute) 6. Pulmonary artery early-systolic notching (proximally-located, higher-risk PE) 7. McConnell's sign (acute) 8. Right atrial enlargement (equal to left atrial size suggests acute, greater than left atrial size suggests chronic).

CONCLUSIONS

Emergency physicians must appreciate the echocardiographic findings and associated pathophysiology that help distinguish acute and chronic right ventricular dysfunction. In the proper clinical context, these findings can point towards PE or PH, thereby leading to earlier goal-directed management.

Normative values of non-invasively assessed RV function and pulmonary circulation coupling for pre-participation screening derived from 497 male elite athletes

BACKGROUND

Reference values for right ventricular function and pulmonary circulation coupling were recently established for the general population. However, normative values for elite athletes are missing, even though exercise-related right ventricular enlargement is frequent in competitive athletes.

METHODS

We examined 497 healthy male elite athletes (age 26.1 ± 5.2 years) of mixed sports with a standardized transthoracic echocardiographic examination. Tricuspid annular plane excursion (TAPSE) and systolic pulmonary artery pressure (SPAP) were measured. Pulmonary circulation coupling was calculated as TAPSE/SPAP ratio. Two age groups were defined (18-29 years and 30-39 years) and associations of clinical parameters with the TAPSE/SPAP ratio were determined and compared for each group.

RESULTS

Athletes aged 18-29 (n = 349, 23.8 ± 3.5 years) displayed a significantly lower TAPSE/SPAP ratio (1.23 ± 0.3 vs. 1.31 ± 0.33 mm/mmHg, p = 0.039), TAPSE/SPAP to body surface area (BSA) ratio (0.56 ± 0.14 vs. 0.6 ± 0.16 mm*m2/mmHg, p = 0.017), diastolic blood pressure (75.6 ± 7.9 vs. 78.8 ± 10.7 mmHg, p < 0.001), septal wall thickness (10.2 ± 1.1 vs. 10.7 ± 1.1 mm, p = 0.013) and left atrial volume index (27.5 ± 4.5 vs. 30.8 ± 4.1 ml/m2, p < 0.001), but a higher SPAP (24.2 ± 4.5 vs. 23.2 ± 4.4 mmHg, p = 0.035) compared to athletes aged 30-39 (n = 148, 33.1 ± 3.4 years). TAPSE was not different between the age groups. The TAPSE/SPAP ratio was positively correlated with left ventricular stroke volume (r = 0.133, p = 0.018) and training amount per week (r = 0.154, p = 0.001) and negatively correlated with E/E' lat. (r = -0.152, p = 0.005).

CONCLUSION

The reference values for pulmonary circulation coupling determined in this study could be used to interpret and distinguish physiological from pathological cardiac remodeling in male elite athletes.

The Pleiotropic Role of Extracellular ATP in Myocardial Remodelling

Myocardial remodelling is a molecular, cellular, and interstitial adaptation of the heart in response to altered environmental demands. The heart undergoes reversible physiological remodelling in response to changes in mechanical loading or irreversible pathological remodelling induced by neurohumoral factors and chronic stress, leading to heart failure. Adenosine triphosphate (ATP) is one of the potent mediators in cardiovascular signalling that act on the ligand-gated (P2X) and G-protein-coupled (P2Y) purinoceptors via the autocrine or paracrine manners. These activations mediate numerous intracellular communications by modulating the production of other messengers, including calcium, growth factors, cytokines, and nitric oxide. ATP is known to play a pleiotropic role in cardiovascular pathophysiology, making it a reliable biomarker for cardiac protection. This review outlines the sources of ATP released under physiological and pathological stress and its cell-specific mechanism of action. We further highlight a series of cardiovascular cell-to-cell communications of extracellular ATP signalling cascades in cardiac remodelling, which can be seen in hypertension, ischemia/reperfusion injury, fibrosis, hypertrophy, and atrophy. Finally, we summarize current pharmacological intervention using the ATP network as a target for cardiac protection. A better understanding of ATP communication in myocardial remodelling could be worthwhile for future drug development and repurposing and the management of cardiovascular diseases.

Left Ventricular, Left Atrial and Right Ventricular Strain Modifications after Maximal Exercise in Elite Ski-Mountaineering Athletes: A Feasibility Speckle Tracking Study

Eleven world elite ski-mountaineering (Ski-Mo) athletes were evaluated for pronounced echocardiographic physiological remodeling as the primary aim of our feasibility speckle tracking study. In this context, sports-related cardiac remodeling was analyzed by performing two-dimensional echocardiography, including speckle tracking analysis of the left atrium (LA), right ventricle (RV) and left ventricular (LV) global longitudinal strain (LV-GLS) at rest and post-peak performance. The feasibility echocardiographic speckle tracking analysis was performed on eleven elite Ski-Mo athletes, which were obtained in 2022 during the annual medical examination. The obtained data of the professional Ski-Mo athletes (11 athletes, age: 18-26 years) were compared for different echocardiographic parameters at rest and post-exercise. Significant differences were found for LV-GLS mean (p = 0.0036) and phasic LA conduit strain pattern at rest and post-exercise (p = 0.0033). Furthermore, negative correlation between LV mass and LV-GLS (p = 0.0195, r = -0.69) and LV mass Index and LV-GLS (p = 0.0253, r = -0.66) at rest were elucidated. This descriptive reporting provided, for the first time, a sport-specific dynamic remodeling of an entire elite national team of the Ski-Mo athlete's left heart and elucidated differences in the dynamic deformation pattern of the left heart.

Right heart exercise-training-adaptation and remodelling in endurance athletes

Long-term sports training leads to myocardial adaptations, with remodelling of the heart chambers. However, while myocardial adaptations of the left heart are well described, remodelling of the right heart and its impact on the development of arrhythmias is still debated. To conduct a systematic review on right ventricle (RV) and right atrium (RA) structural and functional changes in athletes who participate in long-term endurance training. Systematic review. A systematic literature search was conducted. All the articles reporting right heart echocardiographic (ECHO) and cardiac magnetic resonance (CMR) parameters evaluated in endurance athletes and sedentary subjects were considered eligible. A multivariate analysis was conducted to investigate whether age, sex, body surface area (BSA), intensity of training are associated with RV ECHO, CMR parameters and RA ECHO parameters. A positive association between age and right atrium area (RAA) (P = 0.01) was found. This is a negative association to RV E/A (P = 0.004), and RV end diastolic diameter (RVED) longitudinal (P = 0.01). A positive association between BSA and RVED middle (P = 0.001), as well between BSA and RAA (P = 0.05) was found, along with a negative association with RV E/A (P = 0.002). A positive association between intensity of training and RV end systolic area (RVESA) (P = 0.03), RV end diastolic volume indexed (RVEDVI) (P = 0.01), RV end systolic volume indexed (RVESVI) (P = 0.01) was found, along with a negative association with ejection fraction (EF %) (P = 0.01). Endurance athletes demonstrated an association between RV remodelling and age, BSA and intensity of training.

The Role of Multimodality Imaging in Athlete's Heart Diagnosis: Current Status and Future Directions

“Athlete’s heart” is a spectrum of morphological and functional changes which occur in the heart of people who practice physical activity. When athlete’s heart occurs with its most marked expression, it may overlap with a differential diagnosis with certain structural cardiac diseases, including cardiomyopathies, valvular diseases, aortopathies, myocarditis, and coronary artery anomalies. Identifying the underlying cardiac is essential to reduce the potential for sudden cardiac death. For this purpose, a spectrum of imaging modalities, including rest and exercise stress echocardiography, speckle tracking echocardiography, cardiac magnetic resonance, computed tomography, and nuclear scintigraphy, can be undertaken. The objective of this review article is to provide to the clinician a practical step-by-step approach, aiming at distinguishing between extreme physiology and structural cardiac disease during the athlete’s cardiovascular evaluation.

Excessive Treadmill Training Produces different Cardiac-related MicroRNA Profiles in the Left and Right Ventricles in Mice

High-volume training followed by inadequate recovery may cause overtraining. This process may undermine the protective effect of regular exercise on the cardiovascular system and may increase the risk of pathological cardiac remodelling. We evaluated whether chronic overtraining changes cardiac-related microRNA profiles in the left and right ventricles. C57BL/6 mice were divided into the control, normal training, and overtrained by running without inclination, uphill running or downhill running groups. After an 8-week treadmill training protocol, the incremental load test and training volume results showed that the model had been successfully established. The qRT-PCR results showed increased cardiac miR-1, miR-133a, miR-133b, miR-206, miR-208b and miR-499 levels in the left ventricle of the downhill running group compared with the left ventricle of the control group. Similarly, compared with the control group, the downhill running induced increased expression of miR-21, miR-17–3p, and miR-29b in the left ventricle. Unlike the changes in the left ventricle, no difference in the expression of the tested miRNAs was observed in the right ventricle. Briefly, our results indicated that overtraining generally affects key miRNAs in the left ventricle (rather than the right ventricle) and that changes in individual miRNAs may cause either adaptive or maladaptive remodelling with overtraining.

Arrhythmogenic right ventricular cardiomyopathy and sports activity: from molecular pathways in diseased hearts to new insights into the athletic heart mimicry

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited disease associated with a high risk of sudden cardiac death. Among other factors, physical exercise has been clearly identified as a strong determinant of phenotypic expression of the disease, arrhythmia risk, and disease progression. Because of this, current guidelines advise that individuals with ARVC should not participate in competitive or frequent high-intensity endurance exercise. Exercise-induced electrical and morphological para-physiological remodelling (the so-called 'athlete's heart') may mimic several of the classic features of ARVC. Therefore, the current International Task Force Criteria for disease diagnosis may not perform as well in athletes. Clear adjudication between the two conditions is often a real challenge, with false positives, that may lead to unnecessary treatments, and false negatives, which may leave patients unprotected, both of which are equally inacceptable. This review aims to summarize the molecular interactions caused by physical activity in inducing cardiac structural alterations, and the impact of sports on arrhythmia occurrence and other clinical consequences in patients with ARVC, and help the physicians in setting the two conditions apart.

Exercise Dose Associated With Military Service: Implications for the Clinical Management of Inherited Risk for Arrhythmogenic Right Ventricular Cardiomyopathy

INTRODUCTION

High levels of aerobic exercise in individuals who have a gene mutation associated with arrhythmogenic right ventricular cardiomyopathy (ARVC) are associated with clinical disease progression. Guidelines consequently restrict patients from competitive athletics. However, there is minimal literature to guide the safe dosing of physical activity outside of the setting of competitive athletics. Patients may be physically active pursuant to a variety of careers, including military service. This study aimed to define a therapeutic window for exercise for ARVC gene-positive individuals that are compatible with continuing military service and general health while maintaining a level of exercise below that which risks disease progression.

MATERIALS AND METHODS

Using standard metabolic equations, we calculated the minimum VO2 max (amount of oxygen utilized at peak exercise capacity) required to pass the physical fitness tests for each branch. We then developed a sample exercise prescription to maintain this level of fitness. We compared the prescribed exercise load with the physical activity levels associated with non-inferior clinical outcomes in ARVC gene-positive individuals. Additionally, we determined the physical activity exposure sustained by service members based on self-report data and compared these values with the upper limit of safe exercise exposure.

RESULTS

Based on a review of the currently available literature, aerobic exercise exposure less than 700 to 1,100 MET-hours/year (metabolic equivalent-hours per year) is not associated with inferior clinical outcomes for gene-positive individuals. A military service member needs 600 to 700 MET-hours/year to minimally pass the physical fitness test. However, many military members are exercising in excess of this minimum, with typical exposures between 900 and 2,400 MET-hours/year.

CONCLUSIONS

A therapeutic window of aerobic exercise may exist for ARVC gene-positive individuals which would allow continuation of military service while maintaining levels of exercise restriction associated with non-inferior clinical outcomes.

Handling confounding variables in statistical shape analysis - application to cardiac remodelling

Statistical shape analysis is a powerful tool to assess organ morphologies and find shape changes associated to a particular disease. However, imbalance in confounding factors, such as demographics might invalidate the analysis if not taken into consideration. Despite the methodological advances in the field, providing new methods that are able to capture complex and regional shape differences, the relationship between non-imaging information and shape variability has been overlooked. We present a linear statistical shape analysis framework that finds shape differences unassociated to a controlled set of confounding variables. It includes two confounding correction methods: confounding deflation and adjustment. We applied our framework to a cardiac magnetic resonance imaging dataset, consisting of the cardiac ventricles of 89 triathletes and 77 controls, to identify cardiac remodelling due to the practice of endurance exercise. To test robustness to confounders, subsets of this dataset were generated by randomly removing controls with low body mass index, thus introducing imbalance. The analysis of the whole dataset indicates an increase of ventricular volumes and myocardial mass in athletes, which is consistent with the clinical literature. However, when confounders are not taken into consideration no increase of myocardial mass is found. Using the downsampled datasets, we find that confounder adjustment methods are needed to find the real remodelling patterns in imbalanced datasets.

The arrhythmogenic right ventricular cardiomyopathy in comparison to the athletic heart

Intense exercise-induced right ventricular remodeling is a potential adaptation of cardiac function and structure. The features of the remodeling may overlap with those of a very early form of arrhythmogenic right ventricular cardiomyopathy (ARVC): at this early stage, it could be difficult to discriminate ARVC, from exercise-induced cardiac adaptation that may develop in normal individuals. The purpose of this paper is to discuss which exercise-induced remodeling may be a pathological or a physiological finding. A complete evaluation may be required to identify the pathological features of ARVC that would include potential risk of sudden cardiac death during sport or, to avoid the false diagnosis of ARVC. The most recent expert assessment of arrhythmogenic cardiomyopathy focuses on endurance athletes presenting with clinical features indistinguishable from ARVC.

Three-dimensional regional bi-ventricular shape remodeling is associated with exercise capacity in endurance athletes

AIMS

Endurance athletes develop cardiac remodeling to cope with increased cardiac output during exercise. This remodeling is both anatomical and functional and shows large interindividual variability. In this study, we quantify local geometric ventricular remodeling related to long-standing endurance training and assess its relationship with cardiovascular performance during exercise.

METHODS

We extracted 3D models of the biventricular shape from end-diastolic cine magnetic resonance images acquired from a cohort of 89 triathlon athletes and 77 healthy sedentary subjects. Additionally, the athletes underwent cardio-pulmonary exercise testing, together with an echocardiographic study at baseline and few minutes after maximal exercise. We used statistical shape analysis to identify regional bi-ventricular shape differences between athletes and non-athletes.

RESULTS

The ventricular shape was significantly different between athletes and controls (p < 1e-6). The observed regional remodeling in the right heart was mainly a shift of the right ventricle (RV) volume distribution towards the right ventricular infundibulum, increasing the overall right ventricular volume. In the left heart, there was an increment of left ventricular mass and a dilation of the left ventricle. Within athletes, the amount of such remodeling was independently associated to higher peak oxygen pulse (p < 0.001) and weakly with greater post-exercise RV free wall longitudinal strain (p = 0.03).

CONCLUSIONS

We were able to identify specific bi-ventricular regional remodeling induced by long-lasting endurance training. The amount of remodeling was associated with better cardiopulmonary performance during an exercise test.

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.

Metabolic Mechanisms of Exercise-Induced Cardiac Remodeling

Exercise has a myriad of physiological benefits that derive in part from its ability to improve cardiometabolic health. The periodic metabolic stress imposed by regular exercise appears fundamental in driving cardiovascular tissue adaptation. However, different types, intensities, or durations of exercise elicit different levels of metabolic stress and may promote distinct types of tissue remodeling. In this review, we discuss how exercise affects cardiac structure and function and how exercise-induced changes in metabolism regulate cardiac adaptation. Current evidence suggests that exercise typically elicits an adaptive, beneficial form of cardiac remodeling that involves cardiomyocyte growth and proliferation; however, chronic levels of extreme exercise may increase the risk for pathological cardiac remodeling or sudden cardiac death. An emerging theme underpinning acute as well as chronic cardiac adaptations to exercise is metabolic periodicity, which appears important for regulating mitochondrial quality and function, for stimulating metabolism-mediated exercise gene programs and hypertrophic kinase activity, and for coordinating biosynthetic pathway activity. In addition, circulating metabolites liberated during exercise trigger physiological cardiac growth. Further understanding of how exercise-mediated changes in metabolism orchestrate cell signaling and gene expression could facilitate therapeutic strategies to maximize the benefits of exercise and improve cardiac health.

Prevalence and significance of notched T-waves in elite professional cyclists

OBJECTIVES

To identify the frequency and significance of notched T-waves (NTW) in elite endurance athletes.

METHODS

Professional cyclists were followed for 4 years with a clinical, electrocardiographic and echocardiographic assessment. Electrocardiograms were classified according to the presence or absence of NTWs; clinical and echocardiographic correlates were assessed.

RESULTS

42 Caucasian male cyclists were included. NTW were detected in 8 (19%) cyclists who showed significantly longer QT (461 ± 15 vs 422 ± 33 ms, p < 0.01) and QTc intervals (434 ± 19 vs 383 ± 21 ms, p < 0.01), a larger left ventricular end-diastolic volume (163 ± 27 vs 137 ± 23 mL, p = 0.014), end-diastolic volume index (84 ± 13 vs 73 ± 11 mL, p = 0.037) and end-diastolic apex-to-base length (9.9 ± 0.7 vs 9.3 ± 0.5 mm. p = 0.035). There were no detected arrhythmic events, and echocardiography did not reveal any abnormalities.

CONCLUSIONS

This is to our knowledge the first study reporting a high prevalence of NTW in athletes. In our small cohort of cyclists NTW were associated with QT interval prolongation and left ventricular changes. This may be indicative of underlying inhomogeneity of repolarisation. Expanding on this research could reveal a role for NTW in identifying ventricular morphological changes.

Lesson of the month 1: Case reports of arrhythmogenic cardiomyopathies in military personnel

In military recruits, sudden cardiac death rates have been reported as varying from 2 to 13 per 100,000 per year which are mostly related to exercise. However, the development of structural heart changes that may be associated with ventricular arrhythmias have not been reported among this cohort, despite them undergoing endurance training similar to athletes. Here, we report two cases where military personnel were found to have life-threatening cardiac arrhythmias associated with structural heart disease, highlighting the importance of early recognition and treatment of these arrhythmias.

Elevated LV Mass and LV Mass Index Sign on the Athlete's ECG: Athletes' Hearts are Prone to Ventricular Arrhythmia

OBJECTIVES

Intense exercise elevates all heart chambers' dimensions, left ventricular mass (LV mass), and left ventricular mass index (LV mass index). The relationship between increased ventricular arrhythmias and sudden cardiac death with LV dilatation and elevated LV mass has been previously demonstrated. We investigated whether sports-related LV dilatation and elevated LV mass and LV mass index cause an increase in ventricular repolarization heterogeneity.

PATIENTS AND METHODS

This prospective observational study recruited 565 participants. There were 226 (female: 28) athletes and 339 (female: 45) healthy controls between 17 and 42 years of age. They were evaluated using 12-lead-electrocardiography and transthoracic echocardiography. Electrocardiograms were obtained at a rate of 50 mm/s and an amplitude of 10 mV, including at least 3 QRS complexes for each derivation. They were taken with 12 standard deviations. Transmural dispersion of repolarization indexes (TDR) (Tp-Te interval, Tp-Te/QT ratio and Tp-Te/QTc ratio, Tp-Te(d)) were measured from precordial derivations. Measurements weretakenwith a program which was generated with MATLAB codes.

RESULTS

Tp-Te interval, Tp-Te/QT ratio, Tp-Te/QTc ratio, Tp-Te(d), PW (posterior wall thickness), IVS (interventricular septal thickness), LVEDD (left ventricular end-diastolic diameter), LV mass (left ventricular mass), and LV mass index (left ventricular mass index) for the athlete group were significantly higher than for the control group. Correlation analyses revealed that TDR indexes significantly correlated with PW, IVS, LVEDD, LV mass, and LV mass index.

CONCLUSION

LV mass and LV mass index increase in well-trained athletes, and this increase leads to an increase in TDR indexes. The increased frequency of ventricular arrhythmia and sudden cardiac death may be explained with increasing ventricular repolarization heterogeneity in these individuals.

Right Ventricular Structure and Function in the Veteran Ultramarathon Runner: Is There Evidence for Chronic Maladaptation?

BACKGROUND

It has been proposed that chronic exposure to prolonged strenuous exercise may result in maladaptation of the right ventricle (RV). The aim of this study was to establish RV structure and function, including septal insertion points, using conventional echocardiography and myocardial strain (ε) imaging in a veteran population of ultramarathon runners (UR) and age- and sex-matched controls.

METHODS

A retrospective study design provided 40 UR (>35 years old; mean ± SD training experience, 18 ± 12 years) and 24 sedentary controls who had previously undergone conventional two-dimensional, tissue Doppler and speckle-tracking echocardiography to measure RV size and function. Peak RV ε and strain rate (SR) were assessed from the base, mid, and apical lateral wall. SR were assessed during systole (SRs'), early diastole (SRe') and late diastole (SRa'). Regional assessment of RV insertion points was made at the basal inferoseptum and apical septum using left ventricular (LV) longitudinal ε and at the anteroseptum and inferoseptum using LV circumferential and radial ε.

RESULTS

All structural indices of RV size were significantly larger in UR. RV regional and global peak ε were not different between groups, whereas basal RV SR was significantly lower in UR. UR had significantly higher peak LV circumferential ε (anteroseptum, -26% ± 8% vs -21% ± 6%; inferoseptum, -25% ± 6% vs -16% ± 9%) and higher peak LV longitudinal ε (apical septum, -28% ± 7% vs -22% ± 4%) compared with controls. There was regional heterogeneity in UR that was not observed in controls with significantly lower longitudinal ε at the basal inferoseptal insertion point when compared with the global ε (-19% ± 2% vs -22% ± 4%).

CONCLUSIONS

Myocardial ε imaging highlights no overt maladaptation in this cohort of veteran UR, although lower insertion point ε, compared with global ε, in UR may warrant further investigation.

Right ventricular function during pharmacological and exercise stress testing in horses

The disproportionate rise of pulmonary artery pressure compared to systemic blood pressure during exercise can lead to detrimental right ventricular remodelling in endurance athletes. Horses may act as an extreme model of these athletic cardiovascular adaptations, as they show a three fold increase in pulmonary pressures during exercise. Right ventricular function was examined in ten healthy horses using post-exercise and pharmacological stress echocardiography in a randomised cross-over design. Exercise testing was performed on a treadmill while pharmacological testing was performed using an atropine-dobutamine infusion. Heart rate, systemic blood pressure and cardiac output during echocardiography were similar post-exercise compared to maximal pharmacological stress. Systolic pulmonary artery pressure was significantly higher during the exercise test (121±15mmHg) and during immediate post-exercise echocardiography (93±10mmHg) compared to maximal pharmacological stress (69±12mmHg). Right ventricular diameters as well as the ratio of systolic right to left ventricular area were higher post-exercise. Right ventricular fractional area change was significantly decreased post-exercise (40.5±6.2%) compared to a significant increase during pharmacological stress echocardiography (72.6±7.3%). Serum cardiac troponin I concentration was significantly higher 2h after the pharmacological test compared to baseline values and post-exercise, although the highest value was found post-exercise in the horse with the highest systolic pulmonary artery pressure and lowest right ventricular fractional area change. Pharmacological stress testing is not recommended in further studies on right ventricular adaptations in athletic horses, as this does not reproduce the effects of exercise.

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.

Acute and Chronic Effects of Noninvasive Ventilation on Left and Right Myocardial Function in Patients with Obstructive Sleep Apnea Syndrome: A Speckle Tracking Echocardiographic Study

BACKGROUND

In patients with obstructive sleep apnea syndrome (OSAS), repetitive hypoxia due to sleep-induced apnea adversely affects the interaction between myocardial oxygen demand and supply, resulting in the development of subclinical cardiac dysfunction. The purpose of the study was to analyze the different involvement of left and right heart myocardial function in patients with OSAS treated with noninvasive ventilation (NIV).

METHODS

Conventional Doppler echocardiography, Doppler myocardial imaging (DMI), and two-dimensional speckle tracking echocardiography (2DSTE) of left (LV) and right ventricular (RV) longitudinal and right atrial (RA) deformation were performed in 55 patients with OSAS undergoing NIV (M/F 38/17; mean age 67.8 ± 11.2 years). LV and RV global longitudinal strain (GLS) was calculated by averaging local strain along the entire right and left ventricle, before and during NIV, and after 6 months of nocturnal NIV therapy.

RESULTS

LV morphology was comparable before and during NIV, whereas LV ejection fraction and LV DMI early diastolic peak velocity were significantly improved in patients with OSAS during NIV, as was LV regional peak myocardial strain (P < 0.001). RV diameters were slightly increased in patients with OSAS during ventilation, whereas pulmonary artery systolic pressure (PASP), RV GLS, and regional peak myocardial RV strain were significantly reduced during ventilation (P < 0.0001). RA transverse diameters and RA area were also slightly increased during NIV, whereas RA lateral wall strain was reduced (P < 0.001). Acute RV myocardial impairment completely reversed at follow-up, with a decrease in PASP and subsequent increase in both RV and RA myocardial performance.

CONCLUSIONS

Conventional 2DSTE is a useful tool for assessing left and right heart morphology and myocardial deformation in patients with OSAS and for monitoring both acute and chronic effects of NIV.