The Acute Impact of Endurance Exercise on Right Ventricular Structure and Function: A Systematic Review and Meta-analysis

There have been many studies since the late 1980s investigating the effect of endurance exercise on the left ventricle. More recently, attention has shifted to the right heart, with suggestions that endurance exercise may have a detrimental effect on the right ventricle. This systematic review and meta-analysis summarizes and critiques 26 studies, including 649 athletes, examining the acute impact of endurance exercise on the right ventricle. We also present a subanalysis contrasting ultraendurance with endurance exercise. Finally, we identify areas for future research, such as the influence of sex, ethnicity, and age.

Strenuous Endurance Exercise and the Heart: Physiological versus Pathological Adaptations

Although the benefits of regular physical activity on cardiovascular health are well established, the effects of strenuous endurance exercise (SEE) have been a matter of debate since ancient times. In this article, we aim to provide a balanced overview of what is known about SEE and the heart-from epidemiological evidence to recent cardiac imaging findings. Lifelong SEE is overall cardioprotective, with endurance master athletes showing in fact a youthful heart. Yet, some lines of research remain open, such as the need to elucidate the time-course and potential relevance of transient declines in heart function (or increases in biomarkers of cardiac injury) with SEE. The underlying mechanisms and clinical relevance of SEE-associated atrial fibrillation, myocardial fibrosis, or high coronary artery calcium scores also remain to be elucidated. © 2022 American Physiological Society. Compr Physiol 12:1-19, 2022.

Exercise-Induced Cardiac Fatigue in Recreational Ultramarathon Runners at Moderate Altitude: Insights From Myocardial Deformation Analysis

Background

Controversy exists on the actual occurrence of exercise-induced cardiac fatigue (EICF) with ultraendurance exercise, as well as on whether factors such as age or training status might predispose to this condition. The present study aimed to assess the occurrence of EICF among recreational ultramarathon runners, as well as to determine potential predictive factors.

Methods

Nineteen male recreational runners (42 ± 12yrs) participated in a 55-km trial race at moderate altitude (1,800–2,500 m). Participants were evaluated before and after the race using Doppler echocardiography and myocardial deformation analysis. EICF was determined as a reduction >5% of either left ventricular global longitudinal strain (LVGLS) or right ventricular free wall strain (RVFWS). Demographical (age, body mass index), training (training experience, volume and intensity), competition (finishing time, relative intensity) and biochemical variables (blood lactate, creatine kinase [CK] and CK-MB) were assessed as predictors of EICF.

Results

A significant reduction in LVGLS (20.1 ± 2.1% at baseline vs. 18.8 ± 2.4% at post-race, p = 0.026), but not in RVFWS (27.4 ± 7.0 vs. 24.6 ± 5.3%, p = 0.187), was observed after the race. EICF was present in 47 and 71% of the participants attending to the decrease in LVGLS and RVFWS, respectively. No associations were found between any of the analyzed variables and EICF except for age, which was associated with the magnitude of decrement of RVFWS (r = 0.58, p = 0.030).

Conclusions

Ultramarathon running at moderate altitude seems to induce EICF in a considerable proportion of recreational athletes.

Differential negative effects of acute exhaustive swim exercise on the right ventricle are associated with disproportionate hemodynamic loading

Acute exhaustive endurance exercise can differentially impact the right ventricle (RV) versus the left ventricle (LV). However, the hemodynamic basis for these differences and its impact on postexercise recovery remain unclear. Therefore, we assessed cardiac structure and function along with hemodynamic properties of mice subjected to single bouts (216 ± 8 min) of exhaustive swimming (ES). One-hour after ES, LVs displayed mild diastolic impairment compared with that in sedentary (SED) mice. Following dobutamine administration to assess functional reserve, diastolic and systolic function were slightly impaired. Twenty-four hours after ES, LV function was largely indistinguishable from that in SED. By contrast, 1-h post swim, RVs showed pronounced impairment of diastolic and systolic function with and without dobutamine, which persisted 24 h later. The degree of RV impairment correlated with the time-to-exhaustion. To identify hemodynamic factors mediating chamber-specific responses to ES, LV pressure was recorded during swimming. Swimming initiated immediate increases in heart rates (HRs), systolic pressure, dP/dt_max and -dP/dt_min, which remained stable for ∼45 min. LV end-diastolic pressures (LVEDP) increased to ≥45 mmHg during the first 10 min and subsequently declined. After 45 min, HR and -dP/dt_min declined, which correlated with gradual elevations in LVEDP (to ∼45 mmHg) as mice approached exhaustion. All parameters rapidly normalized postexercise. Consistent with human studies, our findings demonstrate a disproportionate negative impact of acute exhaustive exercise on RVs that persisted for at least 24 h. We speculate that the differential effects of exhaustive exercise on the ventricles arise from a ∼2-fold greater hemodynamic load in the RV than in LV originating from profound elevations in LVEDPs as mice approach exhaustion.NEW & NOTEWORTHY Acute exhaustive exercise differentially impacts the right ventricle (RV) versus left ventricle (LV), yet the underlying hemodynamic basis remains unclear. Using pressure-volume analyses and pressure-telemetry implantation in mice, we confirmed a marked disproportionate and persistent negative impact of exhaustive exercise on the RV. These differences in responses of the ventricles to exhaustive exercise are of clinical relevance, reflecting ∼2-fold greater hemodynamic RV loads versus LVs arising from massive (∼45 mmHg) increases in LV end-diastolic pressures at exhaustion.

Prevalence and pattern of cardiovascular magnetic resonance late gadolinium enhancement in highly trained endurance athletes

BACKGROUND

Intensive endurance exercise may induce a broad spectrum of right ventricular (RV) adaptation/remodelling patterns. Late gadolinium enhancement (LGE) has also been described in cardiovascular magnetic resonance (CMR) of some endurance athletes and its clinical meaning remains controversial. Our aim was to characterize the features of contrast CMR and the observed patterns of the LGE distribution in a cohort of highly trained endurance athletes.

METHODS

Ninety-three highly trained endurance athletes (> 12 h training/week at least during the last 5 years; 36 ± 6 years old; 53% male) and 72 age and gender-matched controls underwent a resting contrast CMR. In a subgroup of 28 athletes, T1 mapping was also performed.

RESULTS

High endurance training load was associated with larger bi-ventricular and bi-atrial sizes and a slight reduction of biventricular ejection fraction, as compared to controls in both genders (p < 0.05). Focal LGE was significantly more prevalent in athletes than in healthy subjects (37.6% vs 2.8%; p < 0.001), with a typical pattern in the RV insertion points. In T1 mapping, those athletes who had focal LGE had higher extracellular volume (ECV) at the remote myocardium than those without (27 ± 2.2% vs 25.2 ± 2.1%; p < 0.05).

CONCLUSIONS

Highly trained endurance athletes showed a ten-fold increase in the prevalence of focal LGE as compared to control subjects, always confined to the hinge points. Additionally, those athletes with focal LGE demonstrated globally higher myocardial ECV values. This matrix remodelling and potential presence of myocardial fibrosis may be another feature of the athlete's heart, of which the clinical and prognostic significance remains to be determined.

Cardiac adaptation to endurance exercise training: Differential impact of swimming and running

Objectives: High-intensity training has been associated with bi-ventricular and bi-atrial remodelling and a potentially increased risk of arrhythmias. Most of the evidence is based on endurance disciplines mainly involving the lower part of the body, while few data is available on upper body disciplines. The purpose of this study was to compare chronic cardiac remodelling induced by running and swimming as well as the acute response of ventricular and atrial performance after an upper-body and a lower-body endurance race. Methods: Standard and speckle tracking echocardiographic assessment of left ventricle, right ventricle and both atria was performed at baseline and immediately after a 9.5 km open-water swimming race in 26 healthy men and before and after a 35 km-trail-running race in 21 male runners. Results: No significant differences were observed in baseline ventricular dimensions. However, both right ventricular and atrial systolic deformation were greater in runners. This group also showed slightly larger atrial volumes as compared to swimmers. After the race, right ventricular dilatation was observed in both groups, but only runners showed a decrease in right ventricular deformation and a decrease in atrial volumes and deformation. Significant increases in atrial deformation without reduction in atrial volumes were observed only in swimmers after the race. Conclusions: Right ventricular and atrial remodelling is different depending on the endurance training discipline. Long-distance running races induce a greater impairment in right ventricular performance and atrial function compared to endurance swimming competitions.

Special Article - Exercise-induced right ventricular injury or arrhythmogenic cardiomyopathy (ACM): The bright side and the dark side of the moon

There is still debate on the range of normal physiologic changes of the right ventricle or ventricular (RV) function in athletes. Genetic links to arrhythmogenic cardiomyopathy (ACM) are well-established. There is no current consensus on the importance of extensive exercise and exercise-induced injury to the RV. During the intensive exercise of endurance sports, the cardiac structures adapt to athletic load over time. Some athletes develop RV cardiomyopathy possibly caused by genetic predisposition, whilst others develop arrhythmias from the RV. Endurance sports lead to increased volume and pressure load in both ventricles and increased myocardial mass. The extent of volume increase and changes in myocardial structure contribute to impairment of RV function and pose a challenge in cardiovascular sports medicine. Genetic predisposition to ACM may play an important role in the risk of sudden cardiac death of athletes. In this review, we discuss and evaluate existing results and opinions. Intensive training in competitive dynamic/power and endurance sports leads to specific RV adaptation, but physiological adaptation without genetic predisposition does not necessarily lead to severe complications in endurance sports. Discriminating between physiological adaptation and pathological form of ACM or RV impairment provoked by reinforced exercise presents a challenge to clinical sports cardiologists.

How to interpret right ventricular remodeling in athletes

Long-lasting athletic training induces an overload on the heart that leads to structural, functional, and electrical adaptive changes known as the "athlete's heart." The amount of this heart remodeling has been traditionally considered balanced between the left and the right heart chambers. However, during intense exercise, the right heart is exposed to a disproportional afterload and wall stress which over a long period of time could lead to more pronounced exercise-induced changes. Highly trained athletes, especially those involved in endurance sport disciplines, can develop marked right ventricular (RV) remodeling that could raise the suspicion of an underlying RV pathology including arrhythmogenic cardiomyopathy (ACM). The distinction between physiological and pathological RV remodeling is essential as ACM is a common cause of sudden cardiac death in athletes, and high-intensity exercise training has demonstrated to accelerate its phenotypic expression and worsen its prognosis. The distinction between physiological and pathological RV remodeling is essential since ACM is a common cause of sudden cardiac death in athletes, and high-intensity exercise training has demonstrated to accelerate the phenotypic expression and worsen the prognosis. This article outlines the physiological adaptation of the RV to acute exercise, the subsequent physiological structural and functional changes induced by athletic training and provides useful tips of how to differentiate between physiological RV remodeling and a cardiomyopathy phenotype.

Pulmonary transit of contrast during exercise is related to improved cardio-pulmonary performance in highly trained endurance athletes

BACKGROUND

The mechanisms underlying the high interindividual variability demonstrated for right-ventricular (RV) adaptation to exercise have not yet been identified, but different pulmonary vascular adaptations among individuals could be involved. Pulmonary transit of agitated saline (PTAS) during exercise has been demonstrated to be a good estimator of vascular reserve.

AIM

The aim of this study was to evaluate the presence of PTAS among endurance athletes (EAs) of both sexes and its influence on RV adaptation to exercise.

METHODS

A total of 100 highly trained EAs performed a maximal cardiopulmonary exercise test. Bi-ventricular functional and structural characteristics as well as PTAS were evaluated at baseline and at peak exercise. Athletes were distributed between two groups based on the amount of PTAS during exercise as high (HTPAS; >12 bubbles) and low (LPTAS; ≤12 bubbles).

RESULTS

Overall, 11 EAs exhibited an intra-cardiac shunt at rest and 1 met the criteria for chronic pulmonary disease and were excluded from the study. Among the remaining 88 EAs (51% women), 47 (53%) athletes were classified as HPTAS and 41 (47%) as LPTAS. HPTAS capability was associated with significantly larger RV contractile reserve, larger pulmonary vascular reserve and an enhanced maximal exercise capacity. On multivariate analysis, females were the only independent correlate of the HPTAS capability.

CONCLUSION

In highly trained endurance athletes, a HPTAS capability during exercise corresponded to an increase in pulmonary vascular and RV contractile reserves as well as an enhanced maximal exercise capacity. The long-term clinical or performance implications of the absence or presence of pulmonary shunting, and the subsequent RV afterload increase while performing exercise, remains to be determined.

Exercise-induced cardio-pulmonary remodelling in endurance athletes: Not only the heart adapts

BACKGROUND

The cumulative effects of intensive endurance exercise may induce a broad spectrum of right ventricular remodelling. The mechanisms underlying these variable responses have been scarcely explored, but may involve differential pulmonary vasculature adaptation. Our aim was to evaluate right ventricular and pulmonary circulation in highly trained endurance athletes.

METHODS

Ninety-three highly trained endurance athletes (>12 h training/week at least during the last five years; age: 36 ± 6 years; 52.7% male) and 72 age- and gender-matched controls underwent resting cardiovascular magnetic resonance imaging to assess cardiac dimensions and function, as well as pulmonary artery dimensions and flow. Pulmonary vascular resistance (PVR) was estimated based on left ventricular ejection fraction and pulmonary artery flow mean velocity. Resting and exercise Doppler echocardiography was also performed in athletes to estimate pulmonary artery pressure.

RESULTS

Athletes showed larger biventricular and biatrial sizes, slightly reduced systolic biventricular function, increased pulmonary artery dimensions and reduced pulmonary artery flow velocity as compared with controls in both genders (p < 0.05), which resulted in significantly higher estimated PVR in athletes as compared with controls (2.4 ± 1.2 vs. 1.7 ± 1.1; p < 0.05). Substantially high estimated PVR values (>4.2 WU) were found in seven of the 93 (9.3%) athletes: those exhibiting an enlarged pulmonary artery (indexed area cm²/m²: 4.8 ± 0.6 vs. 3.9 ± 0.6, p < 0.05), a decreased pulmonary artery distensibility index (%: 43.0 ± 15.2 vs. 62.0 ± 17.4, p < 0.05) and a reduced right ventricular ejection fraction (%: 49.3 ± 4.5 vs. 53.6 ± 4.6, p < 0.05).

CONCLUSIONS

Exercise-induced remodelling involves, besides the cardiac chambers, the pulmonary circulation and is associated with an increased estimated PVR. A small subset of athletes exhibited substantial increase of estimated PVR related to pronounced pulmonary circulation remodelling and reduced right ventricular systolic function.

Should the septum be included in the assessment of right ventricular longitudinal strain? An ultrasound two-dimensional speckle-tracking stress study

Right ventricular longitudinal strain (RVLS) by 2D speckle-tracking echocardiography (2D-STE) is a useful parameter for assessing systolic function. However, the exact method to perform it is not well defined as some authors evaluate only free wall (FW) segments while others include all six RV segments. To compare the assessment of RVLS at rest and during exercise by these two approaches. Echocardiography was performed on 80 healthy subjects at rest and during exercise. The analysis consisted of standard and 2D-STE assessment of RV global and segmental strain tracing only RVFW and also tracing all six RV segments. At rest, RVLS could be assessed in 78 (feasibility 97.5%) subjects by both methods. However, during exercise, RVLS by RVFW method was feasible in 67 (83.8%) as compared to 74 (92.5%) by RV6S approach. Both at rest and during exercise, RVLS values by the two methods showed excellent correlation (r =  > 0.90). However, RVLS values assessed by RV6S were lower (absolute values) than those by RVFW approach (RV6S vs. RVFW; rest: - 27.0 ± 3.9 vs. - 9.5 ± 3.9, p < 0.001 and exercise: - 30.7 ± 5.2 vs. - 33.3 ± 5.1, p < 0.001). Furthermore, basal strain was higher and apical strain lower (absolute values) by RV6S approach. At rest, reproducibility for RVLS was excellent and similar for the two methods. However, during exercise, reproducibility for RVFW method was poorer, especially at the apex. The two currently described methods for RVLS assessment by 2D-STE demonstrated excellent agreement. However, the RV6S approach seemed to be more feasible and reproducible, particularly during exercise. Moreover, global and segmental strain values are different with both methods and should not be interchanged.

Cardiac performance after an endurance open water swimming race

PURPOSE

Endurance exercise competitions have shown a transient negative effect on global right ventricular (RV) performance. Most published studies are based on terrestrial sports. The aim of our study was to evaluate the cardiac effects after an open water swimming race.

METHODS

We evaluated 33 healthy swimmers (mean age 40.9 ± 7.2) participating in a 9.5 km open water swimming race. All subjects underwent a standard transthoracic echocardiography including an evaluation of dimensions and myocardial ventricular deformation. Echocardiography was performed 24 h before and within the first hour of arrival at the finish line. Cardiac troponin I (cTn I), NT-ProBNP and leukocytes were also evaluated.

RESULTS

No changes in left ventricle (LV) ejection fraction or LV global longitudinal strain were observed. A significant increase in RV end-diastolic area (RVEDA) was noted after the race (RVEDA at baseline 15.12 ± 1.86; RVEDA after race 16.06 ± 2.27, p < 0.05), but no changes were seen in RV fractional area change or RV global longitudinal strain. Cardiac biomarkers and leukocytes significantly increased. No association was detected between the increase in cTn I or NT-proBNP and the RV acute dilatation or LV performance. A significant association was observed between cTn I and leukocytes (r = 0.375, p < 0.05).

CONCLUSIONS

An acute RV dilatation but without an impairment in RV deformation was observed after participating in an endurance swimming race. The correlation between the increase in cTn I and leukocytes, but not with ventricular performance, may support the hypothesis of an exercise-induced increase in myocardial sarcolemmal permeability due to an inflammatory response rather than myocardial injury.

Exercise-induced shift in right ventricular contraction pattern: novel marker of athlete's heart?

Data about the functional adaptation of the right ventricle (RV) to intense exercise are limited. Our aim was to characterize the RV mechanical pattern in top-level athletes using three-dimensional echocardiography. A total of 60 elite water polo athletes (19 ± 4 yr, 17 ± 6 h of training/wk, 50% women and 50% men) and 40 healthy sedentary control subjects were enrolled. We measured the RV end-diastolic volume index (RVEDVi) and ejection fraction (RVEF) using dedicated software. Furthermore, we determined RV global longitudinal (RV GLS) and circumferential strain (RV GCS) and the relative contribution of longitudinal ejection fraction (LEF) and radial ejection fraction (REF) to RVEF using the ReVISION method. Athletes also underwent cardiopulmonary exercise testing [O₂ consumption (V̇o₂)/kg]. Athletes had significantly higher RVEDVi compared with control subjects (athletes vs. control subjects, 88 ± 11 vs. 65 ± 10 ml/m², P < 0.001); however, they also demonstrated lower RVEF (56 ± 4% vs. 61 ± 5%, P < 0.001). RV GLS was comparable between the two groups (-22 ± 5% vs. -23 ± 5%, P = 0.24), whereas RV GCS was significantly lower in athletes (-21 ± 4% vs. -26 ± 7%, P < 0.001). Athletes had higher LEF and lower REF contribution to RVEF (LEF/RVEF: 0.50 ± 0.07 vs. 0.42 ± 0.07, P < 0.001; REF/RVEF: 0.33 ± 0.08 vs. 0.45 ± 0.08, P < 0.001). Moreover, the pattern of RV functional shift correlated with V̇o₂/kg (LEF/RVEF: r = 0.30, P < 0.05; REF/RVEF: r = -0.27, P < 0.05). RV mechanical adaptation to long-term intense exercise implies a functional shift; the relative contribution of longitudinal motion to global function was increased, whereas the radial shortening was significantly decreased, in athletes. Moreover, this functional pattern correlates with aerobic exercise performance, representing a potential new resting marker of an athlete's heart. NEW & NOTEWORTHY Intensive regular physical exercise results in significant changes of right ventricular morphology and function. By separate quantification of the right ventricular longitudinal and radial function, a relative dominance of longitudinal motion and a decrease in radial motion can be observed compared with sedentary controls. Moreover, this contraction pattern correlates with cardiopulmonary fitness. According to these results, this functional shift of the right ventricle may represent a novel marker of an athlete's heart.

Morphological changes and myocardial function assessed by traditional and novel echocardiographic methods in preadolescent athlete’s heart

Background

Athlete’s heart is a term used to describe the morphological and functional changes in the hearts of athletes. Recent studies suggest that these changes may occur even in preadolescent athletes. This study aims to improve our understanding of the changes occurring in the preadolescent athlete’s heart.

Design and methods

Cardiac morphology and function in 76 preadolescent cross-country skiers (aged 12.1 ± 0.2 years) were compared with 25 age-matched non-competing preadolescents. Echocardiography was performed in all subjects, including 2D speckle-tracking strain echocardiography and 3D echocardiography. All participants underwent cardiopulmonary exercise testing to assess oxygen uptake and exercise capacity.

Results

Athletes had greater indexed VO2 max (62 ± 7 vs. 44 ± 5 mL/kg per min, p < 0.001), indexed left ventricular end-diastolic volume (79 ± 7 vs. 68 ± 7 mL/m2, p < 0.001), left ventricular mass (69 ± 12 vs. 57 ± 13 g/m2, p < 0.001), indexed right ventricular basal diameter (28.3 ± 3.0 vs. 25.4 ± 3.5 mm/m2, p < 0.001) and right atrial area (10.6 ± 1.4 vs. 9.7 ± 1.2 cm2/m2, p < 0.01). There was no difference in left ventricular ejection fraction, global longitudinal strain, and global circumferential strain and right ventricular fractional area change between the groups. Controls had higher right ventricular global longitudinal strain (−28.1 ± 3.5 vs. −31.1 ± 3.3%, p < 0.01). VO2 max was highly correlated to left ventricular end-diastolic volume ( r = 0.76, p < 0.001).

Conclusion

Athletes had greater left ventricular mass and greater left and right ventricular chamber dimensions compared with controls, while left ventricular function did not differ. Interestingly, right ventricular deformation was significantly lower compared with controls. This supports the notion that there is physiological, adaptive remodelling in preadolescent athlete’s heart.

Reference values of left heart echocardiographic dimensions and mass in male peri-pubertal athletes

Background

Several articles have proposed reference values in healthy paediatric subjects, but none of them has evaluated a large population of healthy trained adolescents.

Design

The study purpose was to establish normal echocardiographic measurements of left heart (aortic root, left atrium and left ventricular dimensions and mass) in relation to age, weight, height, body mass index, body surface area and training hours in this specific population.

Methods

We retrospectively evaluated 2151 consecutive, healthy, peri-pubertal athletes (100% male, mean age 12.4 ± 1.4 years, range 8–18) referred to a single centre for pre-participation screening. All participants were young soccer athletes who trained for a mean of 7.2 ± 1.1 h per week.

Results

Left ventricular internal diameters, wall thickness, left ventricular mass, aortic root and left atrium diameters were significantly correlated to age, body surface area, height and weight ( p < 0.01). Age, height, weight and body surface area were found associated with chamber size, while body mass index and training hours were not. Inclusion of both age and body size parameters in the statistical models resulted in improved overall explained variance for diameters and left ventricular mass.

Conclusion

Equations, mean values and percentile charts for the different age groups may be useful as reference data in efficiently assessing left ventricular parameters in young athletes.

Marathon running increases circulating endothelial- and thrombocyte-derived microparticles

Background Acute vascular effects of high intensity physical activity are incompletely characterized. Circulating microparticles are cellular markers for vascular activation and damage. Methods Microparticles were analysed in 99 marathon runners (49 ± 6 years, 22% female) of the prospective Berlin Beat of Running study. Blood samples were taken within three days before, immediately after and within two days after the marathon run. Endothelial-derived microparticles were labelled with CD144, CD31 and CD62E, platelet-derived microparticles with CD62P and CD42b, leukocyte-derived microparticles with CD45 and monocyte-derived microparticles with CD14. Results Marathon running induced leukocytosis (5.9 ± 0.1 to 14.8 ± 0.3 10⁹/l, p < 0.0001) and increased platelet counts (239 ± 4.6 to 281 ± 5.9 10⁹/l, p < 0.0001) immediately after the marathon. Blood monocytes increased and lymphocytes decreased after the run ( p < 0.0001). Endothelial-derived microparticles were acutely increased ( p = 0.008) due to a 23% increase of apoptotic endothelial-derived microparticles ( p = 0.007) and returned to baseline within two days after the marathon. Thrombocyte-derived microparticles acutely increased by 38% accompanied by an increase in activated and apoptotic thrombocyte-derived microparticles ( p ≤ 0.0001) each. Both monocyte- and leukocyte-derived microparticles were decreased immediately after marathon run ( p < 0.0001) and remained below baseline until day 2. Troponin T increased from 12 to 32 ng/l ( p < 0.0001) immediately after the run and returned to baseline after two days. Conclusion Circulating apoptotic endothelial- and thrombocyte-derived microparticles increased after marathon running consistent with an acute pro-thrombotic and pro-inflammatory state. Exercise-induced vascular damage reflected by microparticles could indicate potential mechanisms of post-exertional cardiovascular complications. Further studies are warranted to investigate microparticles as markers to identify individuals prone to such complications.

Severity of structural and functional right ventricular remodeling depends on training load in an experimental model of endurance exercise

Arrhythmogenic right ventricular (RV) remodeling has been reported in response to regular training, but it remains unclear how exercise intensity affects the presence and extent of such remodeling. We aimed to assess the relationship between RV remodeling and exercise load in a long-term endurance training model. Wistar rats were conditioned to run at moderate (MOD; 45 min, 30 cm/s) or intense (INT; 60 min, 60 cm/s) workloads for 16 wk; sedentary rats served as controls. Cardiac remodeling was assessed with standard echocardiographic and tissue Doppler techniques, sensor-tip pressure catheters, and pressure-volume loop analyses. After MOD training, both ventricles similarly dilated (~16%); the RV apical segment deformation, but not the basal segment deformation, was increased [apical strain rate (SR): −2.9 ± 0.5 vs. −3.3 ± 0.6 s−1, SED vs. MOD]. INT training prompted marked RV dilatation (~26%) but did not further dilate the left ventricle (LV). A reduction in both RV segments' deformation in INT rats (apical SR: −3.3 ± 0.6 vs. −3.0 ± 0.4 s−1 and basal SR: −3.3 ± 0.7 vs. −2.7 ± 0.6 s−1, MOD vs. INT) led to decreased global contractile function (maximal rate of rise of LV pressure: 2.53 ± 0.15 vs. 2.17 ± 0.116 mmHg/ms, MOD vs. INT). Echocardiography and hemodynamics consistently pointed to impaired RV diastolic function in INT rats. LV systolic and diastolic functions remained unchanged in all groups. In conclusion, we showed a biphasic, unbalanced RV remodeling response with increasing doses of exercise: physiological adaptation after MOD training turns adverse with INT training, involving disproportionate RV dilatation, decreased contractility, and impaired diastolic function. Our findings support the existence of an exercise load threshold beyond which cardiac remodeling becomes maladaptive.

NEW & NOTEWORTHY Exercise promotes left ventricular eccentric hypertrophy with no changes in systolic or diastolic function in healthy rats. Conversely, right ventricular adaptation to physical activity follows a biphasic, dose-dependent, and segmentary pattern. Moderate exercise promotes a mild systolic function enhancement at the right ventricular apex and more intense exercise impairs systolic and diastolic function.

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.