Myocardial adaptation and efficiency in response to intensive physical training in elite speedskaters

Integrated machine learning and multimodal data fusion for patho-phenotypic feature recognition in iPSC models of dilated cardiomyopathy

Integration of multiple data sources presents a challenge for accurate prediction of molecular patho-phenotypic features in automated analysis of data from human model systems. Here, we applied a machine learning-based data integration to distinguish patho-phenotypic features at the subcellular level for dilated cardiomyopathy (DCM). We employed a human induced pluripotent stem cell-derived cardiomyocyte (iPSC-CM) model of a DCM mutation in the sarcomere protein troponin T (TnT), TnT-R141W, compared to isogenic healthy (WT) control iPSC-CMs. We established a multimodal data fusion (MDF)-based analysis to integrate source datasets for Ca2+ transients, force measurements, and contractility recordings. Data were acquired for three additional layer types, single cells, cell monolayers, and 3D spheroid iPSC-CM models. For data analysis, numerical conversion as well as fusion of data from Ca2+ transients, force measurements, and contractility recordings, a non-negative blind deconvolution (NNBD)-based method was applied. Using an XGBoost algorithm, we found a high prediction accuracy for fused single cell, monolayer, and 3D spheroid iPSC-CM models (≥92 ± 0.08 %), as well as for fused Ca2+ transient, beating force, and contractility models (>96 ± 0.04 %). Integrating MDF and XGBoost provides a highly effective analysis tool for prediction of patho-phenotypic features in complex human disease models such as DCM iPSC-CMs.

Exploratory assessment of right ventricular structure and function during prolonged endurance cycling exercise

BACKGROUND

A reduction in right ventricular (RV) function during recovery from prolonged endurance exercise has been documented alongside RV dilatation. A relative elevation in pulmonary artery pressure and therefore RV afterload during exercise has been implicated in this post-exercise dysfunction but has not yet been demonstrated. The current study aimed to assess RV structure and function and pulmonary artery pressure before, during and after a 6-h cycling exercise bout.

METHODS

Eight ultra-endurance athletes were recruited for this study. Participants were assessed prior to exercise supine and seated, during exercise at 2, 4 and 6 h whilst cycling seated at 75% maximum heart rate, and post-exercise in the supine position. Standard 2D, Doppler and speckle tracking echocardiography were used to determine indices of RV size, systolic and diastolic function.

RESULTS

Heart rate and RV functional parameters increased from baseline during exercise, however RV structural parameters and indices of RV systolic and diastolic function were unchanged between in-exercise assessment points. Neither pulmonary artery pressures (26 ± 9 mmHg vs 17 ± 10 mmHg, P > 0.05) nor RV wall stress (7.1 ± 3.0 vs 6.2 ± 2.4, P > 0.05) were significantly elevated during exercise. Despite this, post-exercise measurements revealed RV dilation (increased RVD1 and 3), and reduced RV global strain (- 21.2 ± 3.5 vs - 23.8 ± 2.3, P = 0.0168) and diastolic tissue velocity (13.8 ± 2.5 vs 17.1 ± 3.4, P = 0.019) vs pre-exercise values.

CONCLUSION

A 6 h cycling exercise bout at 75% maximum heart rate did not alter RV structure, systolic or diastolic function assessments during exercise. Pulmonary artery pressures are not elevated beyond normal limits and therefore RV afterload is unchanged throughout exercise. Despite this, there is some evidence of RV dilation and altered function in post-exercise measurements.

Left ventricular vortex formation time: emerging clinical applications and limitations

Vortex formation during left ventricular diastolic filling may provide clinically useful insights into cardiac health. In recent years, there has been growing interest in the measurement of vortex formation time (VFT), especially because it is derived noninvasively. There are important applications of VFT in valvular heart disease, athletic physiology, heart failure and hypertrophic cardiomyopathy. The formation of the vortex as fluid propagates into the left ventricle from the left atrium is important for efficient fluid transport. Quantifying VFT may thus help in evaluating and understanding disease and pathophysiological processes.

Non-negative blind deconvolution for signal processing in a CRISPR-edited iPSC-cardiomyocyte model of dilated cardiomyopathy

We developed an integrated platform for analysis of parameterized data from human disease models. We report a non-negative blind deconvolution (NNBD) approach to quantify calcium (Ca²⁺ ) handling, beating force and contractility in human-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) at the single-cell level. We employed CRISPR/Cas gene editing to introduce a dilated cardiomyopathy (DCM)-causing mutation in troponin T (TnT), TnT-R141W, into wild-type control iPSCs (MUT). The NNDB-based method enabled data parametrization, fitting and analysis in wild-type controls versus isogenic MUT iPSC-CMs. Of note, Cas9-edited TnT-R141W iPSC-CMs revealed significantly reduced beating force and prolonged contractile event duration. The NNBD-based platform provides an alternative framework for improved quantitation of molecular disease phenotypes and may contribute to the development of novel diagnostic tools.

Echocardiographic evaluation of the Athlete's heart

Cardiac response to prolonged, intense exercise induces phenotypic and physiologic adaptive changes that improve myocardial ability to meet oxygen demands. These adaptations, termed "athletes' heart," have been extensively studied. The importance of this entity arises from the increasing numbers of athletes as well as the drive for physical fitness in the general population leading to adaptive cardiac changes that need to be differentiated from life-threatening cardiovascular diseases. A number of pathologic entities may share phenotypic changes with the athletes' heart such as hypertrophic cardiomyopathy, dilated cardiomyopathy, Marfan's syndrome, and arrhythmogenic right ventricular cardiomyopathy. Cardiologists need to be cognizant of these overlapping findings to appropriately diagnose diseases and prevent catastrophic outcomes especially in young and healthy individuals who may not show any symptoms until they engage in intense exercise. It is equally important to recognize and distinguish normal, exercise-adaptive cardiac changes to provide accurate screening and guidance to young elite athletes. Echocardiography is a valuable modality that allows comprehensive initial evaluation of cardiac structures, function, and response to exercise. Several different echocardiographic techniques including M-Mode, 2D echo, Doppler, tissue Doppler, color tissue Doppler, and speckle tracking have been used in the evaluation of cardiac adaptation to exercise. The following discussion is a review of literature that has expanded our knowledge of the athlete's heart.

Talent Development in Young Cross-Country Skiers: Longitudinal Analysis of Anthropometric and Physiological Characteristics

Introduction: Very little is known about talent development and selection processes in young cross-country skiers.

Aim: (1) to analyze the effect of age on anthropometric and physiological parameters in medium-to-high level cross-country skiers during the late teenage period; (2) to describe parameters' trend in selected talents after the late teenage period; (3) to define which characteristics during the late teenage period could discriminate against further talent selection.

Method: We found 14 male (M) and nine (F) athletes in our database, identified as talents by regional teams during the late teenage period, who performed the same diagonal-stride roller-skiing incremental test to exhaustion at 17 and 18 years old. Of these, four M and three F teenagers performed four further evaluations, and were selected by the national team. Age effect during the late teenage period was verified on anthropometric and physiological parameters measured at maximal intensity (MAX), first (VT1), and second (VT2) ventilatory thresholds, and 3° and 6° of treadmill incline. An observational analysis allowed to evaluate parameters' trend after the late teenage period in selected athletes, and to determine possible characteristics early discriminating further selection.

Results: During the late teenage period, height, weight, and BMI was still raising in M as well as V'O₂ at VT2 and 6° of treadmill incline (all P > 0.05). In F, mass-scaled V'O₂ MAX increased while heart rate (HR) at MAX and VT2 decreased (all P > 0.05). Since the late teenage period, all selected males showed maximal ventilation volumes, absolute V'O₂ at MAX, VT1, and VT2 that were within or above the 75th percentile of their group; the same was found in selected females for mass-scaled V'O₂ MAX, VT1, and VT2 time. After the late teenage period, all selected athletes showed an increasing trend for VT2 time, while a decreasing trend for sub-maximal energetic cost, %V'O₂ and HR.

Discussion: During the late teenage period, males are still completing their maturation process. Since the late teenage period, some physiological parameters seem good indicators to early discriminate for further talents. A progressive increase in skiing efficiency was demonstrated in developing talents of both sexes after the late teenage period.

The impact of demographic, anthropometric and athletic characteristics on left atrial size in athletes

The structural adaptations of the “athlete's heart” include left atrial (LA) enlargement. A literature search was performed based on PubMed listings up to November 2, 2019 using “athletes AND left atrium,” “athletes AND LA,” “sports AND left atrium,” “sports AND LA,” “exercise AND left atrium,” and “exercise AND LA” as the search terms. Eligible studies included those reporting the influence of demographic, anthropometric and athletic characteristics on LA size in athletes. A total of 58 studies were included in this review article. Although LA volume has been reported to be greater in males compared to females when indexed for body surface area (BSA), there was no difference between sexes. The positive association between LA size and age in athletes may reflect the increase in body size with maturation in nonadult athletes and the training age of endurance athletic activity in adult athletes. Caucasian and black athletes have been demonstrated to exhibit similar LA enlargement. The positive association of LA size with lean body mass (LBM) possibly accounts for the relationship of LA size with BSA. LA enlargement has been reported only in endurance‐trained, but not in strength‐trained athletes. LA size appears to increase with an increase in both the volume and intensity of endurance training. LA size correlates independently with the training age of endurance athletes. The athlete's characteristics that independently determine LA size include LBM, endurance training, and training age.

Left ventricular vortex formation time in elite athletes: novel predictor of myocardial performance

Background

Efficient transportation of blood through the left ventricle (LV) during diastole depends on vortex formation. Vortex formation time (VFT) can be measured by echocardiography as a dimensionless index. As elite athletes have supranormal diastolic LV function, we aim to assess resting and post-exercise VFT in these athletes and hypothesised that VFT may predict myocardial performance immediately post-exercise.

Method

Subjects were world class speedskaters training for the Winter Olympic Games. Echocardiographic measurements were obtained before and immediately after 3000 m of racing. VFT was computed as 4×(1-β)/π×α³×left ventricle ejection fraction where β is the fraction of diastolic stroke volume contributed by atrial contraction, α is the biplane end diastolic volume (EDV)^1/3 divided by mitral annular diameter during early diastole.

Results

Baseline VFT was 2.6±0.7 (n=24, age 22±3 years, 67% males). Post-exercise, heart rates increased (64±10 vs 89±12 beats/min, p<0.01); however, VFT was unchanged (2.9±1.0, p>0.05). VFT at rest correlated modestly with post-exertion early diastolic mitral in-flow velocity (E; r=0.59, p=0.01), tissue Doppler-derived early mitral annular velocity (E'; septal and lateral, both r=0.59, p=0.01) and systolic annular velocity (S'; septal: r=0.46, p=0.02 and lateral: r=0.48, p=0.02) but not late diastolic mitral in-flow velocity (A; r=0.06, p>0.05) or annular velocity (A'; septal: r=0.34, p=NS and lateral: r=0.35, p>0.05).

Conclusion

There was no significant difference between VFT at rest and immediately post-exercise. However, VFT at rest correlated with immediate post-exercise augmented systolic and early diastolic tissue Doppler indicators of myocardial performance in elite athletes.

Left atrial volume in elite athletes: A meta-analysis of echocardiographic studies

AIM

Information on left atrium (LA) enlargement, as assessed by LA volume (LAV) instead of LA diameter, in the athletic population is scanty. To expand current knowledge on this issue, we performed an updated meta-analysis of echocardiographic studies.

DESIGN

The Ovid MEDLINE, PubMed, and Cochrane CENTRAL databases were searched for English language articles without time restriction up to February 2018 through focused, high sensitive search strategies. Studies were identified by crossing the following search terms: "athletes," "physical training," "left atrial size," "left atrial volume," "atrial function," and "echocardiography.".

RESULTS

Overall, 3145 subjects (2425 elite athletes and 720 active but not trained healthy controls) were included in 16 studies. Average LAV indexed to BSA (LAVI) was 37% higher in athletes as compared to nonathletic controls (31.0 ± 1.4 mL/m² vs 22.2 ± 0.9 mL/m² ), the standard means difference (SMD) being 1.12 ± 0.13 (CI: 0.86-1.89, P < 0.0001). SMD was higher in high-dynamic/high-static trained athletes (1.78 ± 0.24, CI: 1.30-2.20, P < 0.001) than in high-dynamic/low-static trained athletes 1.00 ± 0.16, CI: 0.70-1.30, P < 0.001). The statistical difference did not change after correction for publication bias and was not affected by a single study effect.

CONCLUSIONS

Our meta-analysis suggests that the adaptation of LA to intensive physical training in elite athletes is characterized by a marked increase in LAVI; LA dilation is more pronounced in the subgroup of high-dynamic/high-static trained athletes. The functional and clinical implications related to advanced LA dilation in athletes and particularly in those engaged in high-dynamic/high-static disciplines deserve further investigations.

Cardiac Imaging In Athletes

Athletic heart syndrome refers to the physiological and morphological changes that occur in a human heart after repetitive strenuous physical exercise. Examples of exercise-induced changes in the heart include increases in heart cavity dimensions, augmentation of cardiac output, and increases in heart muscle mass. These cardiac adaptations vary based on the type of exercise performed and are often referred to as sport-specific cardiac remodeling. The hemodynamic effects of endurance and strength training exercise lead to these adaptations. Any abnormalities in chamber dilatation and left ventricular function usually normalize with cessation of exercise. Athletic heart syndrome is rare and should be differentiated from pathologic conditions such as hypertrophic cardiomyopathy, left ventricular noncompaction, and arrhythmogenic right ventricular dysplasia when assessing a patient for athletic heart syndrome. This paper describes specific adaptations that occur in athletic heart syndrome and tools to distinguish between healthy alterations versus underlying pathology.

Performance characteristics of long-track speed skaters: a literature review

Speed skating is an intriguing sport to study from different perspectives due to the peculiar way of motion and the multiple determinants for performance. This review aimed to identify what is known on (long-track) speed skating, and which individual characteristics determine speed skating performance. A total of 49 studies were included. Based on a multidimensional performance model, person-related performance characteristics were categorized in anthropometrical, technical, physiological, tactical, and psychological characteristics. Literature was found on anthropometry, technique, physiology, and tactics. However, psychological studies were clearly under-represented. In particular, the role of self-regulation might deserve more attention to further understand mechanisms relevant for optimal performance and for instance pacing. Another remarkable finding was that the technically/biomechanically favourable crouched skating technique (i.e. small knee and trunk angle) leads to a physiological disadvantage: a smaller knee angle may increase the deoxygenation of the working muscles. This is an important underlying aspect for the pacing tactics in speed skating. Elite speed skaters need to find the optimal balance between obtaining a fast start and preventing negative technical adaptations later on in the race by distributing their available energy over the race in an optimal way. More research is required to gain more insight into how this impacts on the processes of fatigue and coordination during speed skating races. This can lead to a better understanding on how elite speed skaters can maintain the optimal technical characteristics throughout the entire race, and how they can adapt their pacing to optimize all identified aspects that determine performance.

Cardiac systolic regional function and synchrony in endurance trained and untrained females

Background

Most studies on cardiac function in athletes describe overall heart function in predominately male participants. We aimed to compare segmental, regional and overall myocardial function and synchrony in female endurance athletes (ATH) and in age-matched sedentary females (CON).

Methods

In 46 ATH and 48 CON, echocardiography was used to measure peak longitudinal systolic strain and myocardial velocities in 12 left ventricular (LV) and 2 right ventricular (RV) segments. Regional and overall systolic function were calculated together with four indices of dyssynchrony.

Results

There were no differences in regional or overall LV systolic function between groups, or in any of the four dyssynchrony indices. Peak systolic velocity (s′) was higher in the RV of ATH than in CON (9.7±1.5 vs 8.7±1.5 cm/s, p=0.004), but not after indexing by cardiac length (p=0.331). Strain was similar in ATH and CON in 8 of 12 LV myocardial segments. In septum and anteroseptum, basal and mid-ventricular s′ was 6–7% and 17–19% higher in ATH than in CON (p<0.05), respectively, while s′ was 12% higher in CON in the basal LV lateral wall (p=0.013). After indexing by cardiac length, s′ was only higher in ATH in the mid-ventricular septum (p=0.041).

Conclusions

We found differences between trained and untrained females in segmental systolic myocardial function, but not in global measures of systolic function, including cardiac synchrony. These findings give new insights into cardiac adaptation to endurance training and could also be of use for sports cardiologists evaluating female athletes.

Left Atrium Size in Elite Athletes

OBJECTIVES

The goal of this study was to perform a meta-analysis of the published literature to investigate the relationship of high levels of exercise training to left atrial (LA) size.

BACKGROUND

The "athlete's heart" is a series of cardiac adaptations to systematic exercise training and may include LA enlargement.

METHODS

We conducted a systematic review of English-language studies in MEDLINE and Scopus from inception through April 29, 2014, that reported LA size in elite athletes.

RESULTS

A total of 54 studies comprising 7,189 elite athletes and 1,375 controls were included. Forty-eight of the 54 studies reported absolute LA diameter in 7,018 athletes and 1,044 controls. Nine of the 54 studies (including 992 athletes and 426 controls) presented LA volume corrected for body surface area. The adjusted weighted mean LA diameter was 4.1 mm greater in athletes overall compared with sedentary controls (p < 0.0001), and LA volume index was 7.0 ml/m(2) greater in athletes than controls (p < 0.01). Compared with controls, LA diameter was 4.6 mm greater in endurance-trained athletes (p < 0.0001), 2.9 mm greater in strength-trained athletes (p < 0.03), 3.5 mm greater in combined strength- and endurance-trained athletes (p < 0.0001), and 4.2 mm greater in athletes with unspecified training (p < 0.02).

CONCLUSIONS

To our knowledge, this is the largest compilation of studies documenting that elite athletes have larger LA dimensions compared with controls when evaluated by either LA diameter or LA volume corrected for body surface area. The largest average LA diameters were reported in endurance athletes. Physicians evaluating athletes should be aware that the LA is increased in both strength- and endurance-trained elite athletes.

The Role of Multimodality Cardiac Imaging for the Assessment of Sports Eligibility in Patients with Bicuspid Aortic Valve

Bicuspid aortic valve (BAV) cannot be considered an innocent finding, but it is not necessarily a life-threatening condition. Athletes with BAV should undergo a thorough staging of the valve anatomy, taking into consideration hemodynamic factors, as well as aortic diameters and looking for other associated significant cardiovascular anomalies by use of a multimodality cardiac imaging approach. Furthermore an accurate follow-up is mandatory with serial cardiological controls in those allowed to continue sports.

Gender differences in myocardial function and arterio-ventricular coupling in response to maximal exercise in adolescent floor-ball players

BACKGROUND

The hemodynamic and cardiac responses to exercise have been widely investigated in adults. However, little is known regarding myocardial performance in response to a short bout of maximal exercise in adolescents. We therefore sought to study alterations in myocardial function and investigate sex-influences in young athletes after maximal cardiopulmonary testing.

METHODS

51 adolescent (13-19 years old) floor-ball players (24 females) were recruited. All subjects underwent a maximal exercise test to determine maximal oxygen uptake (VO2max) and cardiac output. Cardiac performance was investigated using conventional and tissue velocity imaging, as well as 2D strain echocardiography before and 30 minutes following exercise. Arterio-ventricular coupling was evaluated by means of single beat ventricular elastance and arterial elastance.

RESULTS

Compared to baseline the early diastolic myocardial velocity (E'LV) at the basal left ventricular (LV) segments declined significantly (females: E'LV: 14.7 +/- 2.6 to 13.6 +/- 2.9 cm/s; males: 15.2 +/- 2.2 to 13.9 +/- 2.3 cm/s, p < 0.001 for both). Similarly, 2D strain decreased significantly following exercise (2D strain LV: from 21.5 +/- 2.4 to 20.2 +/- 2.7% in females, and from 20 +/- 1 to 17.9 +/- 1.5% in males, p < 0.05 for both). However, there were no significant changes in LV contractility estimated by elastance in either sex following exercise (p > 0.05). Arterial elastance) Ea) at baseline was identified as the only predictor of VO2max in males (r = 0.76, p < 0.001) but not in females (p > 0.05).

CONCLUSIONS

The present study demonstrates that vigorous exercise of short duration results in a significant decrease of longitudinal myocardial motion in both sexes. However, in view of unaltered end systolic LV elastance (Ees), these reductions most probably reflect changes in the loading conditions and not an attenuation of myocardial function per se. Importantly, we show that arterial load at rest acts as a strong predictor of VO2max in males but not in female subjects.

The heart of the endurance athlete assessed by echocardiography and its modalities: "embracing the delicate balance"

"To go too far is as bad as to fall short."Confucius (BC 551-BC 479) Chinese philosopher Echocardiography has contributed most to our current understanding and indeed our current dilemma regarding the heart of the endurance athlete. Echocardiography assesses and characterizes nicely the effects of Endurance exercise training. It allows us to assess both systolic and diastolic cardiac variables as they change with structure and function associated with intense sporting activity. Much research work using echocardiography has characterized the left and right ventricle of the endurance athlete over the last year. Indeed evidence suggests that intense prolonged exercise may result in myocardial dysfunction which predominantly affects the RV, and that chronic RV remodelling may represent a substrate for ventricular arrhythmias in athletes. This has been the source of many debates and articles over the last 12 months. The reasons underlying the predilection towards RV dysfunction with intense prolonged exercise and the variation between individuals in its occurrence are still under dispute. This article seeks to describe the recent literature over the last year which outlines the different areas research has focused on when we assess the heart of the endurance athletes using echocardiography. Ultimately the goal of all research on the heart of the endurance athletes is to search for the holy grail of when enough is enough and therefore recognize and embrace the delicate balance of endurance intensity, in other words the border line when endurance exercise is no longer beneficial but slumps and slides into the realms of induced cardiac pathology.

Utility of strain echocardiography at rest and after stress testing in arrhythmogenic right ventricular dysplasia

The introduction of speckle tracking imaging (STI) allowed the quantification of the regional myocardial function in the right ventricular (RV) free wall using deformation parameters. We sought to evaluate the potential utility of STI at rest and after stress to predict arrhythmogenic RV dysplasia (ARVD). We studied 19 patients with ARVD (diagnosed according to the task force criteria) and 19 healthy age- and gender-matched subjects. Both 2-dimensional and 3-dimensional echocardiography were performed. The RV and left ventricular annular peak systolic velocities were measured using tissue Doppler imaging. The RV-left ventricular peak systolic longitudinal strain (LS) was obtained in the basal, mid, and apical segments in the apical 4-chamber view using STI. An exercise stress-echocardiographic test was undertaken using bicycle ergometry with the patient in the supine position for all patients, and the indexes were assessed at peak effort. The STI measurements were determined using offline analysis programs. The 3-dimensional RV ejection fraction and strain were significantly lower in patients with ARVD than in the controls. The RV strain values at rest did not change significantly during maximum physical effort in the patients with ARVD. The receiver operating characteristic curves suggested that the thresholds offering an adequate compromise between sensitivity and specificity for the detection of ARVD were 9.35 cm/s for the RV annular peak systolic velocity (area under the curve 0.81), 42% for 3-dimensional RV ejection fraction (area under the curve 0.85), -25% for mean global RV-LS (area under the curve 0.86), -18% for the lowest peak systolic RV-LS (area under the curve 0.88), and -1.2 for peak minus baseline global change of stress RV-LS (area under the curve 0.92). In conclusion, STI at rest and during stress might enable quantitative assessment of RV function and the detection of ARVD and have potential clinical value in the treatment of these patients.

Doppler echocardiography in athletes from different sports

BACKGROUND

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Comprehensive assessment of biventricular function and aortic stiffness in athletes with different forms of training by three-dimensional echocardiography and strain imaging

AIMS

Previous studies have shown distinct models of cardiac adaptations to the training in master athletes and different effects of endurance and strength-training on cardiovascular function. We attempted to assess left-ventricular (LV) function, aortic (Ao) function, and right-ventricular (RV) function in athletes with different forms of training by using three-dimensional (3D) echocardiography, tissue Doppler imaging (TDI) and speckle-tracking imaging (STI).

METHODS AND RESULTS

We examined 35 male marathon runners (endurance-trained athletes, ETA), 35 powerlifting athletes (strength-trained athletes, STA), 35 martial arts athletes (mixed-trained athletes, MTA), and 35 sedentary untrained healthy men (controls, CTR). Two-dimensional and three-dimensional echocardiography were performed for the assessment of LV and RV systolic/diastolic function. LV and RV longitudinal strain (LS) and LV torsion (LVtor) were determined using STI (EchoPAC BT11, GE-Ultrasound). Maximum velocity of systolic wall expansion peaks (AoSvel) was determined using TDI. ETA experienced LV eccentric hypertrophy with increased 3D LV end-diastolic volume and mass and significant increase in peak systolic apical rotation and LVtor. In all groups of athletes, RV-LS was reduced at rest and improved after exercise. AoSvel was significantly increased in ETA and MTA and significantly decreased in STA compared with CTR. There were good correlations between LV remodelling and aortic stiffness values. Multivariate analysis showed aortic wall velocities to be independently related to LV mass index.

CONCLUSION

In strength-trained, endurance-trained, and mixed-trained athletes, ventricular and vascular response assessed by 3DE, TDI, and STI underlies different adaptations of LV, RV, and aortic indexes.

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

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

A systematic review of resting left ventricular systolic and diastolic function and adaptation in elite weightlifters

BACKGROUND

This review aims to establish what effect weightlifting has on the systolic and diastolic function of the left ventricular (LV).

SOURCES OF DATA

PubMed; ISI Web of Knowledge; Cochrane Library and Ovid Medline were searched in February 2012 to find literature on the effect of weightlifting on the LV cardiac function.

AREAS OF AGREEMENT

Stroke volume, posterior wall thickness and ventricular filling time and rate were seen to increase. A decrease in the resting heart rate was seen.

AREAS OF CONTROVERSY

Blood pressure and LV morphological changes were equivocal.

GROWING POINTS

Weightlifting causes recognizable functional change to the LV, some of these changes may confer benefits such as improvements in the systolic function.

AREAS TIMELY FOR DEVELOPING RESEARCH

Discrepancies exist with regard to regional LV morphological change, as the evidence suggests the LV does not adapt in a homogenous manner. Attempts should be made to separate performance-enhancing drug users from those who compete drug free.

Effect of acute high-intensity interval exercise on postexercise biventricular function in mild heart failure

We studied the acute effect of high-intensity interval exercise on biventricular function using cardiac magnetic resonance imaging in nine patients [age: 49 ± 16 yr; left ventricular (LV) ejection fraction (EF): 35.8 ± 7.2%] with nonischemic mild heart failure (HF). We hypothesized that a significant impairment in the immediate postexercise end-systolic volume (ESV) and end-diastolic volume (EDV) would contribute to a reduction in EF. We found that immediately following acute high-intensity interval exercise, LV ESV decreased by 6% and LV systolic annular velocity increased by 21% (both P < 0.05). Thirty minutes following exercise (+30 min), there was an absolute increase in LV EF of 2.4% (P < 0.05). Measures of preload, left atrial volume and LV EDV, were reduced immediately following exercise. Similar responses were observed for right ventricular volumes. Early filling velocity, filling rate, and diastolic annular velocity remained unchanged, while LV untwisting rate increased 24% immediately following exercise (P < 0.05) and remained 18% above baseline at +30 min (P < 0.05). The major novel findings of this investigation are 1) that acute high-intensity interval exercise decreases the immediate postexercise LV ESV and increases LV EF at +30 min in patients with mild HF, and this is associated with a reduction in LV afterload and maintenance of contractility, and 2) that despite a reduction in left atrial volume and LV EDV immediately postexercise, diastolic function is preserved and may be modulated by enhanced LV peak untwisting rate. Acute high-intensity interval exercise does not impair postexercise biventricular function in patients with nonischemic mild HF.

Echocardiographic findings in professional hockey players

Tissue Doppler imaging was used to evaluate the physiological and morphological response in athletes whose cardiac system must not only adapt to intense cardiovascular demands but also support sudden, transient changes in cardiac output. A total of 45 professional hockey players with a mean age of 24 years underwent a baseline transthoracic echocardiographic protocol after a typical morning workout; 12 healthy age- and gender-matched controls were evaluated as a means of comparison. The athletes in this study possessed larger left ventricular diastolic and systolic dimensions than the control group (5.5 ± 0.4 vs 4.9 ± 0.4 cm and 3.9 ± 0.4 vs 3.3 ± 0.4 cm, P < 0.0001). The increase in athletes' septal and posterior wall thickness was not substantial, nor was there a significant difference in left ventricular ejection fraction. The athletes demonstrated consistently larger left ventricular end-diastolic volume (196 ± 34 vs 136 ± 23 mL, P < 0.001) and end-systolic volume (87 ± 20 vs 57 ± 12 mL, P < 0.0001). They also had lower annular septal and lateral early diastolic and systolic tissue Doppler velocities compared with the control group. Thus, characteristic myocardial changes previously reported in elite athletes were also represented in professional hockey players. The lower left ventricular tissue Doppler velocities was a relatively unique finding and probably a consequence of lower postexertion preload levels compared with controls who were measured at rest.

Athlete's heart: the potential for multimodality imaging to address the critical remaining questions

Moderate exercise is a powerful therapy in the treatment and prevention of cardiac disease, but intense habitual exercise leads to cardiac adaptations for which the prognostic benefits are less clear. The athlete's heart syndrome refers to the morphological and electrical remodeling which occurs to varying extents dependent upon the sporting discipline. Its accurate differentiation from pathological entities is critical. This review describes the role multi-modality imaging serves in determining the limitations and consequences of intense exercise. Tissue characterization and imaging studies during exercise are emphasized as important future directions of inquiry with the potential to address remaining controversies.