The effect of long-term soccer training on left ventricular structure and function in elite male youth soccer players

AIMS

Cardiac adaptations in elite, male adolescent youth soccer players have been demonstrated in relation to training status. The time course of these adaptations and the delineation of the influence of volatile growth phases from the training effect on these adaptations remain unclear. Consequently, the aims of the study were to evaluate the impact of 3 years of elite-level soccer training on changes in left ventricular (LV) structure and function in a group of highly trained elite youth male soccer players (SP) as they transitioned through the pre-to-adolescent phase of their growth.

METHODS

Twenty-two male youth SP from the highest Level of English Premier League Academy U-12 teams were evaluated once a year for three soccer seasons as the players progressed from the U-12 to U-14 teams. Fifteen recreationally active control participants (CON) were also evaluated over the same 3-year period. Two-dimensional transthoracic echocardiography was used to quantify LV structure and function.

RESULTS

After adjusting for the influence of growth and maturation, training-induced increases in Years 2 and 3 were noted for: LV end diastolic volume (LVEDV; p = 0.02) and LV end systolic volume (LVESV; p = 0.02) in the SP compared to CON. Training-induced decrements were noted for LV ejection fraction (LVEF; p = 0.006) and TDI-S' (p < 0.001).

CONCLUSIONS

An increase in training volume (Years 2 and 3) were aligned with LV volumetric adaptations and decrements in systolic function in the SP that were independent from the influence of rapid somatic growth. Decrements in systolic function were suggestive of a functional reserve for exercise.

British Society of Echocardiography guideline for the transthoracic echocardiographic assessment of cardiac amyloidosis

These guidelines form an update of the BSE guideline protocol for the assessment of restrictive cardiomyopathy (Knight et al. in Echo Res Prac, 2013). Since the original recommendations were conceived in 2013, there has been an exponential rise in the diagnosis of cardiac amyloidosis fuelled by increased clinician awareness, improvements in cardiovascular imaging as well as the availability of new and effective disease modifying therapies. The initial diagnosis of cardiac amyloidosis can be challenging and is often not clear-cut on the basis of echocardiography, which for most patients presenting with heart failure symptoms remains the first-line imaging test. The role of a specialist echocardiographer will be to raise the suspicion of cardiac amyloidosis when appropriate, but the formal diagnosis of amyloid sub-type invariably requires further downstream testing. This document seeks to provide a focused review of the literature on echocardiography in cardiac amyloidosis highlighting its important role in the diagnosis, prognosis and screening of at risk individuals, before concluding with a suggested minimum data set, for use as an aide memoire when reporting.

The use of 2-D speckle tracking echocardiography in differentiating healthy adolescent athletes with right ventricular outflow tract dilation from patients with arrhythmogenic cardiomyopathy

AIMS

Echocardiographic assessment of adolescent athletes for arrhythmogenic cardiomyopathy (ACM) can be challenging owing to right ventricular (RV) exercise-related remodelling, particularly RV outflow tract (RVOT) dilation. The aim of this study is to evaluate the role of RV 2-D speckle tracking echocardiography (STE) in comparing healthy adolescent athletes with and without RVOT dilation to patients with ACM.

METHODS AND RESULTS

A total of 391 adolescent athletes, mean age 14.5 ± 1.7 years, evaluated at three sports academies between 2014 and 2019 were included, and compared to previously reported ACM patients (n = 38 definite and n = 39 borderline). Peak systolic RV free wall (RVFW-S_l), global and segmental strain (S_l), and corresponding strain rates (SR_l) were calculated. The participants meeting the major modified Task Force Criteria (mTFC) for RVOT dilation were defined as mTFC+ (n = 58, 14.8%), and the rest as mTFC- (n = 333, 85.2%). Mean RVFW-S_l was -27.6 ± 3.4% overall, -28.2 ± 4.1% in the mTFC+ group and - 27.5 ± 3.3% in the mTFC- group. mTFC+ athletes had normal RV-FW-S_l when compared to definite (-29% vs -19%, p < 0.001) and borderline ACM (-29% vs -21%, p < 0.001) cohorts. In addition, all mean global and regional S_l and SR_l values were no worse in the mTFC+ group compared to the mTFC- (p values range < 0.0001 to 0.1, inferiority margin of 2% and 0.1 s^-1 respectively).

CONCLUSIONS

In athletes with RVOT dilation meeting the major mTFC, STE evaluation of the RV can demostrate normal function and differentiate physiological remodelling from pathological changes found in ACM, improving screening in grey-area cases.

Charter to establish clinical exercise physiology as a recognised allied health profession in the UK: a call to action

The UK population is growing, ageing and becoming increasingly inactive and unfit. Personalised and targeted exercise interventions are beneficial for ageing and the management of chronic and complex conditions. Increasing the uptake of effective exercise and physical activity (PA) interventions is vital to support a healthier society and decrease healthcare costs. Current strategies for exercise and PA at a population level mostly involve self-directed exercise pathways, delivered largely via the fitness industry. Even for those who opt-in and manage to achieve the current recommendations regarding minimum PA, this generic ‘one-size-fits-all’ approach often fails to demonstrate meaningful physiological and health benefits. Personalised exercise prescription and appropriate exercise testing, monitoring and progression of interventions for individuals with chronic disease should be provided by appropriately trained and recognised exercise healthcare professionals, educated in the cognate disciplines of exercise science (eg, physiology, biomechanics, motor control, psychology). This workforce has operated for >20 years in the Australian public and private healthcare systems. Accredited exercise physiologists (AEPs) are recognised allied health professionals, with demonstrable health and economic benefits. AEPs have knowledge of the risks and benefits of distinct forms of exercise, skills in the personalised prescription and optimal delivery of exercise, and competencies to support sustained PA behavioural change, based on the established scientific evidence. In this charter, we propose a road map for the training, accreditation and promotion of a clinical exercise physiology profession in the UK.

5-Year prognostic value of the right ventricular strain-area loop in patients with pulmonary hypertension

Aims

Patients with pre-capillary pulmonary hypertension (PH) show poor survival, often related to right ventricular (RV) dysfunction. In this study, we assessed the 5-year prognostic value of a novel echocardiographic measure that examines RV function through the temporal relation between RV strain (ϵ) and area (i.e. RV ϵ-area loop) for all-cause mortality in PH patients.

Methods and results

Echocardiographic assessments were performed in 143 PH patients (confirmed by right heart catheterization). Transthoracic echocardiography was utilized to assess RV ϵ-area loop. Using receiver operating characteristic curve-derived cut-off values, we stratified patients in low- vs. high-risk groups for all-cause mortality. Kaplan–Meier survival curves and uni-/multivariable cox-regression models were used to assess RV ϵ-area loop’s prognostic value (independent of established predictors: age, sex, N-terminal pro B-type natriuretic peptide, 6-min walking distance). During follow-up 45 (31%) patients died, who demonstrated lower systolic slope, peak ϵ, and late diastolic slope (all P < 0.05) at baseline. Univariate cox-regression analyses identified early systolic slope, systolic slope, peak ϵ, early diastolic uncoupling, and early/late diastolic slope to predict all-cause mortality (all P < 0.05), whilst peak ϵ possessed independent prognostic value (P < 0.05). High RV loop-score (i.e. based on number of abnormal characteristics) showed poorer survival compared to low RV loop-score (Kaplan–Meier: P < 0.01). RV loop-score improved risk stratification in high-risk patients when added to established predictors.

Conclusion

Our data demonstrate the potential for RV ϵ-area loops to independently predict all-cause mortality in patients with pre-capillary PH. The non-invasive nature and simplicity of measuring the RV ϵ-area loop, support the potential clinical relevance of (repeated) echocardiography assessment of PH patients.

Acute exercise-induced changes in cardiac function relates to right ventricular remodeling following 12-wk hypoxic exercise training

Repeated ventricular exposure to alterations in workload may relate to subsequent cardiac remodeling. We examined whether baseline acute changes in right (RV) and left ventricular (LV) function relate to chronic cardiac adaptation to 12-wk exercise training. Twenty-one healthy individuals performed 12-wk high-intensity endurance running training under hypoxia (fraction of inspired oxygen: 14.5%). Resting transthoracic echocardiography was performed before and after the training program to assess ventricular structure, function, and mechanics (including strain-area/volume loops). In addition, we examined systolic cardiac function during recumbent exercise under hypoxia at baseline (heart rate of 110-120 beats/min, "stress echocardiography"). Fifteen individuals completed training (22.0 ± 2.4 yr, 10 males). Hypoxic exercise training increased RV size, including diameter and area (all P < 0.05). With exception of an increase in RV fractional area change (P = 0.03), RV function did not change post-training (all P > 0.05). Regarding the RV strain-area loop, lower systolic and diastolic slopes were found post-training (P < 0.05). No adaptation in LV structure, function, or mechanics was observed (all P > 0.05). To answer our primary aim, we found that a greater increase in RV fractional area change during baseline stress echocardiography (r = -0.67, P = 0.01) inversely correlated with adaptation in RV basal diameter following 12-wk training. In conclusion, 12-wk high-intensity running hypoxic exercise training induced right-sided structural remodeling, which was, in part, related to baseline increase in RV fractional area change to acute exercise. These data suggest that acute cardiac responses to exercise may relate to subsequent RV remodeling after exercise training in healthy individuals.NEW & NOTEWORTHY During exercise, the right ventricle is exposed to a disproportionally higher wall stress than the left ventricle, which is further exaggerated under hypoxia. In this study, we showed that 12-wk high-intensity running hypoxic exercise training induced right-sided structural remodeling, which was, in part, related to baseline cardiac increase in RV fractional area change to acute exercise. These data suggest that acute RV responses to exercise are related to subsequent right ventricular remodeling in healthy individuals upon hypoxic training.

The Psychological and Physiological Consequences of Low Energy Availability in a Male Combat Sport Athlete

PURPOSE

This study aimed to evaluate the effects of low energy availability (EA) on health and performance indices associated with the Male Athlete Triad and Relative Energy Deficiency in Sport (RED-S) models.

METHODS

Over an 8-wk period, a male combat sport athlete adhered to a phased body mass (BM) loss plan consisting of 7-wk energy intake (EI) equating to resting metabolic rate (RMR) (1700 kcal·d-1) (phase 1), 5 d of reduced EI (1200-300 kcal·d-1) before weigh-in (phase 2), and 1 wk of ad libitum EI postcompetition (phase 3). EA fluctuated day by day because of variations in exercise energy expenditure. Regular assessments of body composition, RMR, cardiac function, cardiorespiratory capacity, strength and power, psychological state and blood clinical chemistry for endocrine, bone turnover, hydration, electrolyte, renal, liver, and lipid profiles were performed.

RESULTS

BM was reduced over the 8-wk period by 13.5% (72.5 to 62.7 kg). No consequences of Male Athlete Triad or RED-S were evident during phase 1, where mean daily EA equated to 20 kcal·kg·fat free mass (FFM)-1·d-1 (range, 7 to 31 kcal·kg FFM-1·d-1) and BM and fat mass (FM) losses were 6.5 and 4.4 kg, respectively. However, consequences did present in phase 2 when mean daily EA was consistently <10 kcal·kg FFM-1·d-1, as evidenced by alterations to endocrine hormones (e.g., testosterone <5 nmol.L-1) and reduced RMR (-257 kcal·d-1).

CONCLUSION

Data demonstrate that 7 wk of daily fluctuations in EA equating to a mean value of 20 kcal·kg FFM-1·d-1 permits reductions of BM and FM without perturbations to physiological systems associated with the Male Athlete Triad and RED-S. By contrast, a subsequent period of five consecutive days of EA <10 kcal·kg FFM-1·d-1 induced consequences of Male Athlete Triad and RED-S.

Can right ventricular speckle tracking imaging be used in arrhytmogenic cardiomyopathy screening? A study of healthy paediatric athletes with and without echocardiographic modified task force criteria

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): The study was support by a contractual research partnership between the University of Bristol and Canon Medical Systems UK.

Background

Arrhytmogenic cardiomyopathy (ACM) is a major cause of sudden cardiac death among young athletes. Screening these individuals can be challenging due to right ventricular (RV) exercise-related remodelling, particularly right ventricular outflow tract (RVOT) dilation. Recent studies have also shown that peak RV longitudinal strain (Sl) measured by speckle tracking echocardiography (STE) is reduced in adolescents with definite and borderline ACM. The prevalence of RV changes meeting ACM criteria in healthy paediatric athletes, and whether these changes are associated with abnormal RV strain values is not known.

Purpose

The aim of this study is to evaluate the prevalence of healthy paediatric athletes meeting the ACM echocardiographic modified Task Force Criteria (mTFC) for RVOT dilation, and how this relates to RV longitudinal systolic function.

Methods

Athletes under 18 years old undergoing comprehensive pre-participation screening (2014-2017) at two sports academies were included. Global (RV-Sl) and free wall peak systolic strain (FW-Sl) were calculated using STE. Three groups were defined: meeting the major mTFC for RVOT size (M-mTFC), meeting the minor mTFC (m-mTFC) and not meeting the mTFC (no-mTFC). RV-Sl and FW-Sl were compared using the Kruskall Wallis test.

Results

A total of 247 boys (11.1-18 years, median 14.6 years) were included, with diverse ethnicity (53.1% Arab, 27.6% Black, 17.6% White, and 1.7% other) and sports background (50.6% football, 27.9% athletics, 21.5% other).

Of these n = 22 were in the M-mTFC group (8.9%), n = 93 in the m-mTFC group (37.7%) and n = 132 in the no-mTFC group (53.4%). No regional RV wall motion abnormalities were observed. There were no differences in RV-Sl or FW-Sl by mTFC Group (Table 1).

Conclusions

In healthy paediatric athletes, 9% met the major mTFC, and 38% met the minor mTFC for RVOT size. RV longitudinal strain was found to be similar between those who met the mTFC and those who did not. This highlights the probable non-pathological adaptations reflected by RVOT dilation in these individuals, as opposed to those seen in ACM. The results of this study suggest that STE can be a valuable tool in ACM screening in paediatric athletes, especially in cases where RV remodelling is present.

RV peak longitudinal strain by mTFC All M-mTFC n = 22 m-mTFC n = 93 no-mTFC n = 132 p value for between group comparison Global RV Sl (median, IQR) -23.3% (-25.2;-21.7) -23.3% (-25.5;-21.7) -23.4% (-25;-21.7) -23.3% (-25.5;-21.7) p = 0.8 Free wall RV Sl (median, IQR) 27.7% (-30;-25.2) -27.6% (-29.3;-25.2%) -28.1% (-29.7;-25) -27.5 (-30.5;-25.4) p = 0.9

The acute and chronic effects of high-intensity exercise in hypoxia on blood pressure and post-exercise hypotension: A randomized cross-over trial

BACKGROUND

Acute exercise leads to an immediate drop in blood pressure (BP), also called post-exercise hypotension (PEH). Exercise in hypoxia is related to additional vasodilation, potentially contributing to more profound PEH. Therefore, we investigated the impact of hypoxia versus normoxia on the magnitude of PEH. Second, we examined whether these changes in PEH relate to the BP-lowering effects of 12-week exercise training under hypoxia.

METHODS

In this prospective study, 21 healthy individuals (age 22.2 ± 3.0 years, 14 male) performed a 45-minute high-intensity running exercise on 2 different days in a random order, under hypoxia (fraction of inspired oxygen 14.5%) and normoxia (fraction of inspired oxygen 20.9%). BP was examined pre-exercise (t = 0) and at t = 15, t = 30, t = 45, and t = 60 minutes post-exercise. Afterward, subjects took part in a 12-week hypoxic running exercise training program. Resting BP was measured before and after the 12-week training program.

RESULTS

Acute exercise induced a significant decrease in systolic BP (systolic blood pressure [SBP], P = .001), but not in diastolic BP (diastolic blood pressure [DBP], P = .113). No significant differences were observed in post-exercise BP between hypoxic and normoxic conditions (SBP, P = .324 and DBP, P = .204). Post-exercise changes in SBP, DBP, and mean arterial pressure significantly correlated to the 12-week exercise training-induced changes in SBP (r = 0.557, P = .001), DBP (r = 0.615, P < .001), and mean arterial pressure (r = 0.458, P = .011).

CONCLUSION

Our findings show that hypoxia does not alter the magnitude of PEH in healthy individuals, whilst PEH relates to the BP-lowering effects of exercise. These data highlight the strong link between acute and chronic changes in BP.

Acute impact of changes to hemodynamic load on the left ventricular strain-volume relationship in young and older men

Chronic changes in left ventricular (LV) hemodynamics, such as those induced by increased afterload (i.e., hypertension), mediate changes in LV function. This study examined the proof of concept that 1) the LV longitudinal strain (ε)-volume loop is sensitive to detecting an acute increase in afterload, and 2) these effects differ between healthy young versus older men. Thirty-five healthy male volunteers were recruited, including 19 young (24 ± 2 yr) and 16 older participants (67 ± 5 yr). Tests were performed before, during, and after 10-min recovery from acute manipulation of afterload. Real-time hemodynamic data were obtained and LV longitudinal ε-volume loops were calculated from four-chamber images using two-dimensional echocardiography. Inflation of the anti-gravity (anti-G) suit resulted in an immediate increase in heart rate, blood pressure, and systemic vascular resistance and a decrease in stroke volume (all P < 0.05). This was accompanied by a decrease in LV peak ε, slower slope of the ε-volume relationship during early diastole, and an increase in uncoupling (i.e., compared with systole; little change in ε per volume decline during early diastole and large changes in ε per volume decline during late diastole) (all P < 0.05). All values returned to baseline levels after recovery (all P > 0.05). Manipulation of cardiac hemodynamics caused comparable effects in young versus older men (all P > 0.05). Acute increases in afterload immediately change the diastolic phase of the LV longitudinal ε-volume loop in young and older men. This supports the potency of the LV longitudinal ε-volume loop to provide novel insights into dynamic cardiac function in humans in vivo.

P784 Cardiac remodelling in elite rowers - insights from novel echocardiographic techniques

Funding Acknowledgements

No financial support

Background

Chronic exercise training leads to cardiac remodelling; the so-called Athlete’s Heart. Previous studies are often limited by a cross-sectional design whilst longitudinal training studies are often constrained to the assessment of non-athletes. Echocardiography provides comprehensive assessment of mechanics and may give additional insight into short-term changes in training volume in the elite athlete.

Purpose

To examine the impact of a short-term (9 months) increase in training volume on cardiac structure and mechanics in elite international competing rowers.

Methods

As part of the work-up to the 2012 Olympic Games, twenty-seven elite rowers (26.4 ± 3.7 years, 19 male) underwent baseline echocardiography prior to and post (9-months) a planned increase in training volume. Conventional echocardiographic indices including mechanics of all cardiac chambers were assessed.

Results

In response to increased training volume, there was a significant increase in left ventricular (LV) size (IVSd 9.2 ± 1.2 to 9.7 ± 1.1 mm, p = 0.001; PWd 8.3 ± 1.3 to 8.7 ± 1.4 mm, p = 0.013), LVIDd (56.5 ± 4.6 to 57.9 ± 4.2 mm, p = 0.001), and LVMi (90.2 ± 17.8 to 100.8 ± 17.1 g/m2, p = 0.000), see table. There was a significant increase in LV twist (9.2 ± 4.5 to 11.2 ± 4.7 °, p = 0.04; basal rotation -4.4 ± 3.1 to -4.5 ± 3.4 °, p = 0.84; apical rotation 5.8 ± 3.4 to 7.1 ± 3.7 °, p = 0.011), see figure, however, there were no changes in any other conventional indices of function or any other cardiac mechanics. There was a significant increase in left atrial (LA) volume (58.8 ± 15.2 to 65.3 ± 17.6 mm, p = 0.01) whilst no changes were observed in right heart structure.

Conclusion

An increase in exercise training volume in elite rowers across 9-months induced mild balanced structural remodelling of the LV and LA with a concomitant increase in LV twist. Contradictory to findings in non-athletes, there was no increase in right ventricular or atrial structure or function which may be representative of the elite athlete status and possibly already at threshold for physiological adaptation.

Abstract P784 Figure.

Changes in dynamic left ventricular function, assessed by the strain-volume loop, relate to reverse remodeling after aortic valve replacement

Aortic valve replacement (AVR) leads to remodeling of the left ventricle (LV). Adopting a novel technique to examine dynamic LV function, our study explored whether post-AVR changes in dynamic LV function and/or changes in aortic valve characteristics are associated with LV mass regression during follow-up. We retrospectively analyzed 30 participants with severe aortic stenosis who underwent standard transthoracic echocardiographic assessment before AVR [88 (IQR or interquartile range: 22–143) days], post-AVR [13 (6–22) days], and during follow-up [455 (226–907) days]. We assessed standard measures of LV structure, function, and aortic valve characteristics. Novel insight into dynamic LV function was provided through a four-chamber image by examination of the temporal relation between LV longitudinal strain (ε) and volume (ε-volume loops), representing the contribution of LV mechanics to volume change. AVR resulted in immediate changes in structural valve characteristics, alongside a reduced LV longitudinal peak ε and improved coherence between the diastolic and systolic part of the ε-volume loop (all P < 0.05). Follow-up revealed a decrease in LV mass ( P < 0.05) and improvements in LV ejection fraction and LV longitudinal peak ε ( P < 0.05). A significant relationship was present between decline in LV mass during follow-up and post-AVR improvement in coherence of the ε-volume loops ( r = 0.439, P = 0.03), but not with post-AVR changes in aortic valve characteristics or LV function (all P > 0.05). We found that post-AVR improvements in dynamic LV function are related to long-term remodeling of the LV. This highlights the potential importance of assessing dynamic LV function for cardiac adaptations in vivo.

NEW & NOTEWORTHY Combining temporal measures of left ventricular longitudinal strain and volume (strain-volume loop) provides novel insights in dynamic cardiac function. In patients with aortic stenosis who underwent aortic valve replacement, postsurgical changes in the strain-volume loop are associated with regression of left ventricular mass during follow-up. This provides novel insight into the relation between postsurgery changes in cardiac hemodynamics and long-term structural remodeling, but also supports the potential utility of the assessment of dynamic cardiac function.

Impact of 24 weeks of supervised endurance versus resistance exercise training on left ventricular mechanics in healthy untrained humans

In addition to the well-known cardiac structural adaptation to exercise training, little work has examined changes in left ventricle (LV) mechanics. With new regional and global indexes available we sought to determine the effect of 24-wk endurance versus resistance training on LV mechanics. Twenty-three male subjects were randomly allocated to a 24-wk endurance or resistance training program. Pre- and posttraining two-dimensional echocardiographic images were acquired. Global LV mechanics [strain (ε)] were recorded in longitudinal, circumferential, and radial planes. Rotation was assessed at apical and basal levels. In addition, longitudinal ε-volume loops, across the cardiac cycle, were constructed from simultaneous LV ε (longitudinal and transverse strain) and volume measurements across the cardiac cycle as a novel measure of LV mechanics. Marginal differences in ε and rotation data were found between groups. After training, we found no change in global peak ε data. Peak basal rotation significantly increased after training, with changes in the endurance group (−2.2 ± 1.9° to −4.5 ± 3.3°) and the resistance group (−2.9 ± 3.0° to −3.4 ± 2.9°). LV ε-volume loops revealed a modest rightward shift in both groups. Although most global and regional indexes of LV mechanics were not significantly altered, 24 wk of intense supervised exercise training increased basal rotation. Further studies that assess LV mechanics in larger cohorts of subjects and those with cardiovascular disease and risk factors may reveal important training impacts.

NEW & NOTEWORTHY This study builds on previous work by our group and presents a comprehensive assessment of cardiac mechanics after dichotomous exercise training programs. We highlight novel findings in addition to the inclusion of strain-volume loops, which shed light on subtle differences in longitudinal and transverse contribution to volume change throughout the cardiac cycle. Our findings suggest that training has an impact on basal rotation and possibly strain-volume loops.

Left ventricular function and mechanics following prolonged endurance exercise: an update and meta-analysis with insights from novel techniques

Background

The cardiac consequences of undertaking endurance exercise are the topic of recent debate. The purpose of this review is to provide an update on a growing body of literature, focusing on left ventricular (LV) function following prolonged endurance exercise over 2 h in duration which have employed novel techniques, including myocardial speckle tracking, to provide a more comprehensive global and regional assessment of LV mechanics.

Methods

Prospective studies were filtered independently following a pre-set criteria, resulting in the inclusion of 27 studies in the analyses. A random-effects meta-analysis was used to determine the weighted mean difference and 95% confidence intervals (CI) of LV functional and mechanical data from pre-to-post-exercise. Narrative commentary was also provided where volume of available evidence precluded meta-analysis.

Results

A significant overall reduction in LV longitudinal strain (Ɛ) n = 22 (− 18 ± 1 to − 17 ± 1%; effect size (d) − 9: − 1 to − 0.5%), strain rate n = 10 (SR;d − 0.9: − 0.1.3 to − 0.5 l/s) and twistn = 5 (11.9 ± 2.2 to 8.7 ± 2.2°,d − 1: − 1.6 to − 0.3°) was observed following strenuous endurance exercise (range 120–1740 min) (P < 0.01). A smaller number of studies (n = 4) also reported a non-significant reduction in global circumferential and radial Ɛ (P > 0.05).

Conclusion

The meta-analysis and narrative commentary demonstrated that a reduction in LV function and mechanics is evident following prolonged endurance exercise. The mechanism(s) responsible for these changes are complex and likely multi-factorial in nature and may be linked to right and left ventricular interaction.

Global and regional cardiac function in lifelong endurance athletes with and without myocardial fibrosis

The aim of the present study was to compare cardiac structure as well as global and regional cardiac function in athletes with and without myocardial fibrosis (MF). Cardiac magnetic resonance imaging with late gadolinium enhancement was used to detect MF and global cardiac structure in nine lifelong veteran endurance athletes (58 ± 5 years, 43 ± 5 years of training). Transthoracic echocardiography using tissue-Doppler and myocardial strain imaging assessed global and regional (18 segments) longitudinal left ventricular function. MF was present in four athletes (range 1-8 g) and not present in five athletes. MF was located near the insertion points of the right ventricular free wall on the left ventricle in three athletes and in the epicardial lateral wall in one athlete. Athletes with MF demonstrated a larger end diastolic volume (205 ± 24 vs 173 ± 18 ml) and posterior wall thickness (11 ± 1 vs 9 ± 1 mm) compared to those without MF. The presence of MF did not mediate global tissue velocities or global longitudinal strain and strain rate; however, regional analysis of longitudinal strain demonstrated reduced function in some fibrotic regions. Furthermore, base to apex gradient was affected in three out of four athletes with MF. Lifelong veteran endurance athletes with MF demonstrate larger cardiac dimensions and normal global cardiac function. Fibrotic areas may demonstrate some co-localised regional cardiac dysfunction, evidenced by an affected cardiac strain and base to apex gradient. These data emphasize the heterogeneous phenotype of MF in athletes.

Exploratory assessment of left ventricular strain-volume loops in severe aortic valve diseases

KEY POINTS

Severe aortic valve diseases are common cardiac abnormalities that are associated with poor long-term survival. Before any reduction in left ventricular (LV) function, the left ventricle undergoes structural remodelling under the influence of changing haemodynamic conditions. In this study, we combined temporal changes in LV structure (volume) with alterations in LV functional characteristics (strain, ԑ) into a ԑ-volume loop, in order to provide novel insight into the haemodynamic cardiac consequences of aortic valve diseases in those with preserved LV ejection fraction. We showed that our novel ԑ-volume loop and the specific loop characteristics provide additional insight into the functional and mechanical haemodynamic consequences of severe aortic valve diseases (with preserved LV ejection fraction). Finally, we showed that the ԑ-volume loop characteristics provide discriminative capacity compared with conventional measures of LV function.

ABSTRACT

The purpose of this study was to examine left ventricular (LV) strain (ԑ)-volume loops to provide novel insight into the haemodynamic cardiac consequences of aortic valve stenosis (AS) and aortic valve regurgitation (AR). Twenty-seven participants were retrospectively recruited: AR (n = 7), AS (n = 10) and control subjects (n = 10). Standard transthoracic echocardiography was used to obtain apical four-chamber images to construct ԑ-volume relationships, which were assessed using the following parameters: early systolic ԑ (ԑ_ES); slope of ԑ-volume relationship during systole (Sslope); end-systolic peak ԑ (peak ԑ); and diastolic uncoupling (systolic ԑ-diastolic ԑ at same volume) during early diastole (UNCOUP_ED) and late diastole (UNCOUP_LD). Receiver operating characteristic curves were used to determine the ability to detect impaired LV function. Although LV ejection fraction was comparable between groups, longitudinal peak ԑ was reduced compared with control subjects. In contrast, ԑ_ES and Sslope were lower in both pathologies compared with control subejcts (P < 0.01), but also different between AS and AR (P < 0.05). UNCOUP_ED and UNCOUP_LD were significantly higher in both patient groups compared with control subjects (P < 0.05). Receiver operating characteristic curves revealed that loop characteristics (AUC = 0.99, 1.00 and 1.00; all P < 0.01) were better able then peak ԑ (AUC = 0.75, 0.89 and 0.76; P = 0.06, <0.01 and 0.08, respectively) and LV ejection fraction (AUC = 0.56, 0.69 and 0.69; all P > 0.05) to distinguish AS vs control, AR vs control and AS vs AR groups, respectively. Temporal changes in ԑ-volume characteristics provide novel insight into the haemodynamic cardiac impact of AS and AR. Contrary to traditional measures (i.e. ejection fraction, peak ԑ), these novel measures successfully distinguish between the haemodynamic cardiac impact of AS and AR.

Myocardial Fibrosis in Athletes

Myocardial fibrosis (MF) is a common phenomenon in the late stages of diverse cardiac diseases and is a predictive factor for sudden cardiac death. Myocardial fibrosis detected by magnetic resonance imaging has also been reported in athletes. Regular exercise improves cardiovascular health, but there may be a limit of benefit in the exercise dose-response relationship. Intense exercise training could induce pathologic cardiac remodeling, ultimately leading to MF, but the clinical implications of MF in athletes are unknown. For this comprehensive review, we performed a systematic search of the PubMed and MEDLINE databases up to June 2016. Key Medical Subject Headings terms and keywords pertaining to MF and exercise (training) were included. Articles were included if they represented primary MF data in athletes. We identified 65 athletes with MF from 19 case studies/series and 14 athletic population studies. Myocardial fibrosis in athletes was predominantly identified in the intraventricular septum and where the right ventricle joins the septum. Although the underlying mechanisms are unknown, we summarize the evidence for genetic predisposition, silent myocarditis, pulmonary artery pressure overload, and prolonged exercise-induced repetitive micro-injury as contributors to the development of MF in athletes. We also discuss the clinical implications and potential treatment strategies of MF in athletes.

Two-dimensional strain imaging: a new echocardiographic advance with research and clinical applications

Over the past two decades the quest for quantitative evaluation of left ventricular function and regional wall motion has escalated, allowing several aspects of myocardial contractile patterns to be quantified, both during stress echocardiography and in the assessment of dyssynchrony. Most of the literature to date has used Tissue Doppler Imaging (TDI) techniques to assess essentially long-axis function due to the angle dependency of Doppler based techniques. This brief review introduces the early development, validation and potential clinical applications of a new technique of quantifying two-dimensional (radial and circumferential) strains and strain rates through tracking myocardial "speckles". In-vivo and in-vitro validation of this 2D-strain imaging technique has been undertaken and reached a point where it is considered ready for more widespread investigations into clinical utility. One important advantage over TDI techniques is that it is not limited by dependency on the angle of insonation. Several recent studies looking at ventricular function in specific groups of patients have reported practical ability to distinguish the abnormally from the normally contracting regions of ventricular walls. It provides new and complementary quantitative information about ventricular dyssynchrony and regional wall motion abnormalities. More research studies are needed to determine the sensitivity and specificity of the measurements obtained using this technique and define its strengths and limitations. In particular, whether the measured values correlate well with clinical outcomes will need to be established in longitudinal interventional studies. The clinical utilities of this technique over the coming years are likely to expand rapidly.