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

Burden of premature atrial beats in middle-aged endurance athletes with and without lone atrial fibrillation versus sedentary controls

BACKGROUND

The burden of premature atrial beats (PABs) at 24-h electrocardiographic (ECG) monitoring correlates with the risk of atrial fibrillation. It is unknown whether prolonged and intense exercise increases the burden of PABs, thus contributing to the higher prevalence of atrial fibrillation observed in middle-aged athletes.

METHODS

We compared the burden of PABs at 24-h ECG monitoring off therapy in 134 healthy middle-aged (30-60-year-old) competitive athletes who had practised 9 (7-11) h of endurance sports for 8 (4-15) consecutive years, 134 age- and gender-matched healthy sedentary individuals, and 66 middle-aged patients (20 athletes and 46 non-athletes) with 'lone' paroxysmal atrial fibrillation.

RESULTS

More than 50 PABs/24 h or ≥1 run of ≥3 PABs were recorded in 23/134 (17%) healthy athletes and in 29/134 (22%) sedentary controls (p = 0.61). Healthy athletes with frequent or repetitive PABs were older (median 50 years vs. 43 years, p < 0.01) and had practised sport for a longer time (median 10 years vs. 6 years, p = 0.03). At multivariable analysis only age (odds ratio 1.11, 95% confidence interval 1.04-1.20, p < 0.01) remained an independent predictor of a higher burden of PABs. Also among patients with 'lone' paroxysmal atrial fibrillation, there was no difference in the prevalence of >50 PABs/24 h or ≥1 run of ≥3 PABs between athletes (40%) and controls (48%, p = 0.74).

CONCLUSIONS

Middle-aged endurance athletes, with or without paroxysmal atrial fibrillation, did not show a higher burden of PABs at 24-h ECG monitoring than sedentary controls. Age, but not intensity and duration of sports activity, predicted a higher burden of PABs among healthy athletes.

Left atrial function in elite athletes: A meta-analysis of two-dimensional speckle tracking echocardiographic studies

BACKGROUND

We sought to investigate left atrial (LA) volume, function, and strain in elite athletes by a meta-analysis including echocardiographic studies that provided volumetric and strain analysis of LA phasic function.

METHODS

The OVID-MEDLINE, PubMed, and Cochrane CENTRAL databases were searched for English-language articles without time restriction up to February 2018 through focused and high sensitive search strategies. Studies were identified by crossing the following search terms: "athletes," "left atrial size," "left atrial volume," "atrial function," "atrial strain," "atrial strain rate," "echocardiography," "2D speckle echocardiography."

RESULTS

Meta-analysis included 403 athletes and 314 active but not trained healthy controls from 9 studies. Pooled data showed that average LA volume index was higher in athletes than in healthy controls (28.0 ± 1.0 vs 20.7 ± 0.8 mL/m2 , P < 0.001). Global LA longitudinal strain, showing LA reservoir function, was lower in the athletes than in healthy controls with borderline significance (37.0 ± 1.2 vs 38.3 ± 1.5%, P = 0.044). Late diastolic LA strain rate, resembling LA contractile function, was also lower in elite athletes than in control group (-1.56 ± 0.08 vs -1.74 ± 0.09 seconds -1, P = 0.007).

CONCLUSIONS

Our meta-analysis shows that LA volume is higher, while LA reservoir and contractile functions are impaired in elite athletes during active training compared to untrained controls. Whether these changes persist during deconditioning periods remains to be determined. These alterations may be related to the higher risk of arrhythmias, in particular atrial fibrillation, reported among middle/old aged athletes.

Cardiac Magnetic Resonance Normal Reference Values of Biventricular Size and Function in Male Athlete's Heart

OBJECTIVES

The aim of this meta-analysis was to derive normal reference values of biventricular size and function estimated by cardiac magnetic resonance (CMR) in competitive athletes.

BACKGROUND

Exercise-induced enlargement of cardiac chambers is commonly observed in competitive athletes. However, ventricular dilatation is also a common phenotypic expression of life-threatening cardiomyopathies. The use of CMR for the exclusion of pathology is growing. However, normal reference values have not been established for athletes.

METHODS

The authors conducted a systematic review of English-language studies in the MEDLINE, Scopus, and Cochrane databases investigating biventricular size and function by CMR in athletes. Athletes were divided into endurance, combined, and mixed groups according to the sport practiced. The potential impact of training volume was also evaluated.

RESULTS

Twenty-seven studies and 983 competitive athletes were included for CMR quantification of biventricular size and function. In this review, normal reference values are presented for biventricular size and function to be applied to male competitive athletes according to the disciplines practiced. A significant impact of training volume was demonstrated for the right ventricle: athletes practicing the largest number of training hours per week were those exhibiting the greatest degree of right ventricular remodeling. Notably, biventricular function was not significantly affected by training volume.

CONCLUSIONS

The present meta-analysis defines the normal limits of biventricular size and function estimated by CMR in competitive athletes. The authors suggest using these normal reference values as an alternative to standard upper limits derived from the general population when interpreting CMR images in athletes.

Left atrial functional response after a marathon in healthy amateur volunteers

Middle-aged marathon runners have an increased risk of developing atrial fibrillation (AF). A previous study described that repetitive marathon running was associated with left atrial (LA) dysfunction. However, whether this change is common in marathon runners and which runners are at risk of LA dysfunction remain unknown. The purpose of this study was to determine which factors could predict LA dysfunction. We prospectively examined 12 healthy amateur volunteers (9 males, 31 ± 8 years old) who participated in a full marathon. All echocardiographic measurements and speckle-tracking echocardiography were performed before and after the marathon. The endpoint was defined as reduced LA reservoir strain 1 day after the marathon (non-responder group). Seven participants were in the non-responder group. Age (35 ± 9 vs. 26 ± 2 years, p = 0.020), augmentation index (76 ± 12 vs. 55 ± 8, p = 0.002), and diastolic blood pressures (83 ± 11 vs. 70 ± 7 mmHg, p = 0.021) in the non-responder group were significantly higher compared with the responder group. In multivariate linear regression analysis, only the augmentation index was an independent predictor of reduced LA reservoir function after the marathon (β = - 0.646, p = 0.023). The augmentation index was a predictive marker for reduction in LA reservoir function after a marathon in healthy amateur volunteers.

The Female Athlete's Heart: Facts and Fallacies

Purpose of the review

For many years, competitive sport has been dominated by men. Recent times have witnessed a significant increase in women participating in elite sports. As most studies investigated male athletes, with few reports on female counterparts, it is crucial to have a better understanding on physiological cardiac adaptation to exercise in female athletes, to distinguish normal phenotypes from potentially fatal cardiac diseases. This review reports on cardiac adaptation to exercise in females.

Recent findings

Recent studies show that electrical, structural, and functional cardiac changes due to physiological adaptation to exercise differ in male and female athletes. Women tend to exhibit eccentric hypertrophy, and while concentric hypertrophy or concentric remodeling may be a normal finding in male athletes, it should be evaluated carefully in female athletes as it may be a sign of pathology. Although few studies on veteran female athletes are available, women seem to be affected by atrial fibrillation, coronary atherosclerosis, and myocardial fibrosis less than male counterparts.

Summary

Males and females exhibit many biological, anatomical, and hormonal differences, and cardiac adaptation to exercise is no exception. The increasing participation of women in sports should stimulate the scientific community to develop large, longitudinal studies aimed at a better understanding of cardiac adaptation to exercise in female athletes.

Speckle tracking-derived bi-atrial strain before and after eleven weeks of training in elite rowers

The left (LA) and right (RA) atria undergo adaptive remodeling in response to hemodynamic stress not only induced by endurance exercise but also as part of several cardiovascular diseases thereby confounding differential diagnosis. Echocardiographic assessment of the atria with novel speckle tracking (STE)-derived variables broadens the diagnostic spectrum compared to conventional analyses and has the potential to differentiate physiologic from pathologic changes. The purpose of this study was to assess and categorize baseline values of bi-atrial structure and function in elite rowers according to recommended cutoffs, and to assess the cardiac changes occurring with endurance training. Therefore, fifteen elite rowers underwent 2D-echocardiographic analysis of established variables of cardiac structure and function as well as STE-derived variables of bi-atrial function. Measurements were performed at baseline and after eleven weeks of extensive training. 40% of athletes displayed mildly enlarged LA and 47% mildly enlarged RA at baseline, whereas no athlete fell below the lower reference values of LA and RA reservoir strain. Average power during a 2000 m ergometer rowing test (P2000 m) improved from 426 ± 39 W to 442 ± 34 W (p = 0.010) but there were no changes of echocardiographic variables following training. In elite rowers, longitudinal bi-atrial strain assessment indicates normal resting function of structurally enlarged atria and thereby may assist to differentiate between exercise-induced versus disease-associated structural cardiac changes in which function is commonly impaired.

Regular endurance training in adolescents impacts atrial and ventricular size and function

Aims

The aims of the study were to explore the effects of long-term endurance exercise on atrial and ventricular size and function in adolescents and to examine whether these changes are related to maximal oxygen uptake (VO2max).

Methods and results

Twenty-seven long-term endurance-trained adolescents aged 13-19 years were individually matched by age and gender with 27 controls. All participants, 22 girls and 32 boys, underwent an echocardiographic examination at rest, including standard and colour tissue Doppler investigation. VO2max was assessed during treadmill exercise. All heart dimensions indexed for body size were larger in the physically active group compared with controls: left ventricular end-diastolic volume 60 vs. 50 mL/m2 (P <0.001), left atrial volume 27 vs. 19 mL/m2 (P < 0.001), and right ventricular (RV) and right atrial area 15 vs. 13 and 9 vs. 7 cm2/m2, respectively (P <0.001 for both). There were strong associations between the size of the cardiac chambers and VO2max. Further, we found improved systolic function in the active group compared with controls: left ventricular ejection fraction 61 vs. 59% (P= 0.036), tricuspid annular plane systolic excursion 12 vs. 10 mm/m2 (P= 0.008), and RV early peak systolic velocity s' 11 vs. 10 cm/s (P = 0.031).

Conclusion

Cardiac remodelling to long-term endurance exercise in adolescents is manifested by an increase in atrial as well as ventricular dimensions. The physically active group also demonstrated functional remodelling with an increase in TAPSE and systolic RV wall velocity. These findings have practical implications when assessing cardiac enlargement and function in physically active youngsters.

The ambiguity of physical activity, exercise and atrial fibrillation

Although commonly associated with cardiovascular disease or other medical conditions, atrial fibrillation may also occur in individuals without any known underlying conditions. This manifestation of atrial fibrillation has been linked to extensive and long-term exercise, as prolonged endurance exercise has shown to increase prevalence and risk of atrial fibrillation. In contrast, more modest physical activity is associated with a decreased risk of atrial fibrillation, and current research indicates a J-shaped association between atrial fibrillation and the broad range of physical activity and exercise. This has led to the hypothesis that the mechanisms underlying an increased risk of atrial fibrillation with intensive exercise are different from those underlying a reduced risk with moderate physical activity, possibly linked to distinctive characteristics of the population under study. High volumes of exercise over many years performed by lean, healthy endurance trained athletes may lead to cardiac (patho)physiological alterations involving the autonomic nervous system and remodelling of the heart. The mechanisms underlying a reduced risk of atrial fibrillation with light and moderate physical activity may involve a distinctive pathway, as physical activity can potentially reduce the risk of atrial fibrillation through favourable effects on cardiovascular risk factors.

Gender influence on the adaptation of atrial performance to training

BACKGROUND

High-intensity training has been associated with atrial remodelling and arrhythmias in men. Our purpose was to analyse atrial performance in female endurance athletes, compared to male athletes and controls.

METHODS

This was a cross-sectional study. We included four groups: female athletes, females controls, male athletes and male controls. Left (LA) and right atrial (RA) volumes and function were assessed using 2D and speckle-tracking echocardiography to determine peak atrial strain-rate at atrial (SRa) and ventricular contraction (SRs), as surrogates of atrial contractile and reservoir function, respectively. ANOVA and Bonferroni's statistical tests were used to compare variables among groups.

RESULTS

We included 82 subjects, 39 women (19 endurance athletes, 20 controls) and 43 men (22 endurance athletes, 21 controls). Mean age was similar between groups (36.6 ± 5.6 years). Athletes had larger bi-atrial volumes, compared to controls (women, LA 27.1 vs. 15.8 ml/m², p < 0.001; RA 22.31 vs. 14.2 ml/m², p = 0.009; men, LA: 25.0 vs. 18.5 ml/m², p = 0.003; RA 30.8 vs. 21.9 ml/m², p < 0.001) and lower strain-rate (women, LASRa -1.60 vs. -2.18 s^-1, p < 0.001; RASRa -1.89 vs. -2.38 s^-1, p = 0.009; men, LASRa -1.21 vs. -1.44 s^-1, p = 1; RASRa -1.44 vs. -1.60 s^-1, p = 1). However, RA indexed size was lower and bi-atrial deformation greater in female athletes, compared to male athletes.

CONCLUSIONS

The atria of both male and female athletes shows specific remodelling, compared to sedentary subjects, with larger size and less deformation at rest, particularly for the RA. Despite a similar extent of remodelling, the pattern in women had greater bi-atrial myocardial deformation and smaller RA size.

Strain Imaging Echocardiography: What Imaging Cardiologists Should Know

Despite recent advances in clinical imaging, echocardiography remains as the most accessi-ble and reliable noninvasive. Since knowledge of left ventricular systolic function remains so critically important in determining prognosis; every effort should be made to prevent subjective estimations. The advent of strain imaging echocardiography now offers a readily available and portable imaging tool that not only offers an objective characterization of myocardial dynamics; but also allows for early detection of subclinical left ventricular dysfunction. This review outlines the basic concepts of strain imaging to better understand the mechanism of myocardial function as well their applicability in the least common cardiac diagnosis among current clinical practice.

Echocardiographic Characterization of the Inferior Vena Cava in Trained and Untrained Females

The aim of the study was to explore the long- and short-axis dimensions, shape and collapsibility of the inferior vena cava in 46 trained and 48 untrained females (mean age: 21 ± 2 y). Echocardiography in the subcostal view revealed a larger expiratory long-axis diameter (mean: 24 ± 3 vs. 20 ± 3 mm, p < 0.001) and short-axis area (mean: 5.5 ± 1.5 vs. 4.7 ± 1.4 cm², p = 0.014) in trained females. IVC shape (the ratio of short-axis major to minor diameters) and the relative decrease in IVC dimension with inspiration were similar for the two groups. The IVC long-axis diameter reflected short-axis minor diameter and was correlated to maximal oxygen uptake (r = 0.52, p < 0.01). In summary, the results indicate that trained females have a larger IVC similar in shape and respiratory decrease in dimensions to that of untrained females. The long-axis diameter corresponded closely to short-axis minor diameter and, thus, underestimates maximal IVC diameter.

Left Atrial Enlargement in Young High-Level Endurance Athletes - Another Sign of Athlete's Heart?

Enlargement of the left atrium is perceived as a part of athlete’s heart syndrome, despite the lack of evidence. So far, left atrial size has not been assessed in the context of exercise capacity. The hypothesis of the present study was that LA enlargement in athletes was physiological and fitness-related condition. In addition, we tried to assess the feasibility and normal values of left atrial strain parameters and their relationship with other signs of athlete’s heart. The study group consisted of 114 international-level rowers (17.5 ± 1.5 years old; 46.5% women). All participants underwent a cardio-pulmonary exercise test and resting transthoracic echocardiography. Beside standard echocardiographic measurements, two dimensional speckle tracking echocardiography was used to assess average peak atrial longitudinal strain, peak atrial contraction strain and early left atrial diastolic longitudinal strain. Mild, moderate and severe left atrial enlargement was present in 27.2°%, 11.4% and 4.4% athletes, respectively. There were no significant differences between subgroups with different range of left atrial enlargement in any of echocardiographic parameters of the left ventricle diastolic function, filling pressure or hypertrophy. A significant correlation was found between the left atrial volume index and maximal aerobic capacity (R > 0.3; p < 0.001). Left atrial strain parameters were independent of atrial size, left ventricle hypertrophy and left ventricle filling pressure. Decreased peak atrial longitudinal strain was observed in 4 individuals (3.5%). We concluded that LA enlargement was common in healthy, young athletes participating in endurance sport disciplines with a high level of static exertion and was strictly correlated with exercise capacity, therefore, could be perceived as another sign of athlete’s heart.

Exercise-Induced Atrial Remodeling: The Forgotten Chamber

Cardiac changes in athletes involve the left ventricle and atrium. Mild left atrial enlargement is common among competitive athletes, possibly a physiologic adaptation to exercise conditioning. The prevalence of this remodeling and the association with supraventricular arrhythmias has not been systematically addressed. Echocardiography screens for patients with disease involving the left atrium. New techniques like speckle tracking can recognize early atrial dysfunction and assess left atrial myocardial function in patients with either physiologic or pathologic left ventricular hypertrophy. This article reviews echocardiographic techniques in delineating the athlete's morphology and functional properties of the left atrium.

RV Remodeling in Olympic Athletes

OBJECTIVES

The aim of this study was to assess the impact of sex and different sports on right ventricular (RV) remodeling and compare the derived upper limits with widely used revised Task Force (TF) reference values.

BACKGROUND

Uncertainties exist regarding the extent and physiological determinants of RV remodeling in highly trained athletes. The issue is important, considering that in athletes RV size occasionally exceeds the cutoff limits proposed to diagnose arrhythmogenic RV cardiomyopathy.

METHODS

A total of 1,009 Olympic athletes (mean age 24 ± 6 years; n = 647 [64%] males) participating in skill, power, mixed, and endurance sport were evaluated by 2-dimensional echocardiography and Doppler/tissue Doppler imaging. The right ventricular outflow tract (RVOT) in parasternal long-axis (PLAX) and short-axis views, fractional area change, s' velocity, and morphological features were assessed.

RESULTS

Indexed RVOT PLAX was greater in females than in males (15.3 ± 2.2 mm/m² vs. 14.4 ± 1.9 mm/m²; p < 0.001). Both RVOT PLAX and parasternal short-axis view were significantly different among skill, power, mixed, and endurance sports: 14.3 ± 2.1 mm/m² versus 14.7 ± 1.9 mm/m² versus 14.0 ± 1.8 mm/m² versus 15.7 ± 2.2 mm/m², respectively (p < 0.001); and 15.2 ± 2.7 mm/m² versus 15.3 ± 2.4 mm/m² versus 14.8 ± 2.1 mm/m² versus 16.2 ± 2.5 mm/m², respectively (p < 0.001). The 95th percentile for indexed RVOT PLAX and parasternal short-axis view was 18 mm/m² and 20 mm/m², respectively. Fractional area change and s' velocity did not differ among the groups (p = 0.34 for both). RV enlargement compatible with major and minor TF diagnostic criteria for arrhythmogenic RV cardiomyopathy was observed in 41 (4%) and 319 (32%) athletes. A rounded apex was described in 823 (81%) athletes, prominent trabeculations in 378 (37%) athletes, and a prominent/hyperreflective moderator band in 5 (0.5%) athletes.

CONCLUSIONS

RV remodeling occurs in Olympic athletes, with male sex and endurance practice playing the major impact. A significant subset (up to 32%) of athletes exceeds the normal TF limits; therefore, we recommend referring to the 95th percentiles here reported as referral values; alternatively, only major diagnostic TF criteria for arrhythmogenic RV cardiomyopathy may be appropriate.

Atrial chamber remodelling in healthy pre-adolescent athletes engaged in endurance sports: A study with a longitudinal design. The CHILD study

AIMS

Previous studies investigated the exercise-induced adaptation of left (LA) and right atrium (RA) in adults, but little is known about respective changes in the growing heart of children. We aimed to longitudinally investigate the effects of endurance training on biatrial remodelling in preadolescent athletes.

METHODS AND RESULTS

Ninety-four children (57 endurance athletes, 37 sedentary controls; mean age 10.8±0.2 and 10.2±0.2years, respectively) were evaluated at baseline and after 5months by ECG and by two-dimensional, three-dimensional (3D) and speckle-tracking echocardiography. Athletes were trained at least 10h/week. The resting heart rate was lower in athletes (p=0.046) and decreased further after training (p<0.0001). Neither athletes nor controls had ECG evidence for LA or RA enlargement. At baseline, indexed LA volumes did not differ between groups (p=0.14) but indexed RA dimensions were larger in athletes (p=0.007). After 5months, indexed LA volumes increased in athletes but not in controls (p<0.0001, p=0.29; respectively) while indexed RA volumes increased in both groups (p<0.0001, p=0.018; respectively). At the same time, slight differences in biatrial reservoir and contractile function were found either in athletes, as demonstrated by speckle-tracking echocardiography, but 3D-derived LA and RA ejection fraction remained stable in both groups.

CONCLUSION

Endurance training influences the growing heart of preadolescent athletes with an additive increase in biatrial size, suggesting that morphological adaptations can occur also in the early phases of the sports career. Training-induced remodelling was associated with a preserved biatrial function, supporting the hypothesis of a physiological remodelling.

The right atrium, a forgotten cardiac chamber: An updated review of multimodality imaging

Despite several limitations, two-dimensional echocardiography (2DE) is the standard method for assessing the right atrium (RA) in everyday clinical routine. Cardiac magnetic resonance remains the current "gold standard" for RA visualization and volume quantification. The development of 2DE-derived strain imaging has enabled assessing RA deformation and phasic function in various pathologic conditions. Three-dimensional echocardiography was demonstrated to be more accurate and reproducible than 2DE for cardiac chamber quantification, while also allowing the evaluation of RA phasic function without geometric assumption. The purpose of this review is to summarize currently available data about RA anatomy, phasic function, and mechanics acquired by different imaging modalities.

Echocardiography in the evaluation of athletes

Echocardiography is currently a widely available imaging technique that can provide useful data in the field of sports cardiology particularly in two areas: pre-participation screening and analysis of the cardiac adaptation induced by exercise.

The application of pre-participation screening and especially, the type and number of used diagnostic tests remains controversial. Echocardiography has shown though, higher sensitivity and specificity as compared to the ECG, following a protocol adapted to athletes focused on ruling out the causes of sudden death and the most common disorders in this population. It is still a subject of controversy the actual cost of adding it, but depending on the type of sport, echocardiography might be cost-effective if added in the first line of examination.

Regarding the evaluation of cardiac adaptation to training in athletes,  echocardiography has proved to be useful in the differential diagnosis of diseases that can cause sudden death, analysing both the left ventricle (hypertrophy cardiomyopathy, dilated cardiomyopathy, left ventricle non compaction) and the right ventricle (arrhythmogenic right ventricular cardiomyopathy).

The aim of this paper is to review the current knowledge and the clinical practical implications of it on the field of echocardiography when applied in sport cardiology areas.

Novel echocardiographic techniques for the evaluation of athletes' heart: A focus on speckle-tracking echocardiography

BACKGROUND

The development and rapid dissemination of two-dimensional echocardiography led to important further advances in our understanding of athletes' heart that has been the subject of several echocardiographic studies involving many thousands of athletes. The description of ventricular chamber enlargement, myocardial hypertrophy and atrial dilatation has led to a more comprehensive understanding of cardiac adaptation to exercise conditioning. Most recently, advanced echocardiographic techniques have begun to clarify significant functional adaptations of the myocardium that accompany previously reported morphological features of athletes' heart. In particular, speckle-tracking echocardiography (STE) has recently provided further insights into the characterisation of myocardial properties.

DISCUSSION

STE is a relatively new, largely angle-independent, non-invasive imaging technique that allows for an objective and quantitative evaluation of global and regional myocardial function. STE has enhanced our understanding of athletes' heart through a comprehensive characterisation of biventricular and biatrial function, providing novel insights into the investigation of physiological adaptation of the heart to exercise conditioning. These peculiarities can provide further useful data to distinguish between athletes' heart and cardiomyopathies. Furthermore, STE represents a promising tool to address new concerns on right ventricular function and to increase understanding of the complexity of the non-systemic circulation, especially in the athletic population.

CONCLUSION

This review article analyses new data on cardiac function in athletes by novel echocardiographic techniques with a particular attention to the application of STE to characterise biventricular and biatrial function in athletes.

Cardiovascular Adaptation and Remodeling to Rigorous Athletic Training

Exercise-induced cardiac remodeling is a complex process by which the cardinal hemodynamic stresses of pressure and volume lead to a host of structural or functional adaptations. In aggregate, the constellation of changes that accompany this process serve to facilitate athletic performance by minimizing the cardiac work inherent in athletic activity. Although several key determinants of athletic cardiac adaptation have been described, observed variability across athlete cohorts remains an incompletely understood area. Ongoing and future work are required to further understand this process and ultimately to determine where the boundary lies between adaptive physiology and maladaptive disease.

Gender- and sex-specific sports-related injury research in emergency medicine: a consensus on future research direction and focused application

Title IX, the commercialization of sports, the social change in sports participation, and the response to the obesity epidemic have contributed to the rapid proliferation of participation in both competitive organized sports and nontraditional athletic events. As a consequence, emergency physicians are regularly involved in the acute diagnosis, management, disposition, and counseling of a broad range of sports-related pathology. Three important and highly publicized mechanisms of injury in sports relevant to emergency medicine (EM) include concussion, heat illness, and sudden cardiac death. In conjunction with the 2014 Academic Emergency Medicine consensus conference "Gender-specific Research in Emergency Care: Investigate, Understand, and Translate How Gender Affects Patient Outcomes," a consensus group consisting of experts in EM, emergency neurology, sports medicine, and public health convened to deliberate and develop research questions that could ultimately advance the field of sports medicine and allow for meaningful application in the emergency department (ED) clinical setting. Sex differences in injury risk, diagnosis, ED treatment, and counseling are identified in each of these themes. This article presents the consensus-based priority research agenda.

Chronic adaptation of atrial structure and function in elite male athletes

AIMS

The aim of this study was to establish the degree of structural and functional adaptations in the left (LA) and right atria (RA) in elite male athletes engaged in 'high dynamic : high static' (HDHS) and 'low dynamic : high static' (LDHS) sporting disciplines compared with sedentary controls.

METHODS AND RESULTS

Eighteen male, elite HDHS athletes (13 boxers and 7 triathletes), 18 male, elite LDHS athletes (8 weightlifters and 10 Akido), and 20 male, age-matched sedentary controls were assessed using conventional 2D and myocardial speckle tracking (MST) echocardiography. Absolute LA and RA volumes [end systole (VOLes), pre A (VOLpreA), and end diastole (VOLed)] as well as the functional indices of reservoir (RESvol), conduit (CONvol), and booster volumes (BOOvol) were defined. MST allowed the assessment of atrial strain (ε) during the reservoir (RESε), conduit (CONε), and booster (BOOε) phases of the cardiac cycle. Both LA and RA sizes were significantly larger in HDHS compared with LDHS and controls (P < 0.05) across all structural and functional volume parameters with no significant difference between LDHS and controls (LAVOLes 35 ± 8, 26 ± 10, and 23 ± 5 mL/m(2); RAVOLes 37 ± 10, 26 ± 9, and 23 ± 5 mL/m(2), LARESvol 35 ± 9, 25 ± 11, and 23 ± 7 mL; RARESvol 41 ± 11, 34 ± 11, and 28 ± 7 mL for HDHS, LDHS, and controls, respectively). RA : LA ratios were >1 in all groups due to a comparatively larger RA volume (RAVOLes : LAVOLes 1.05 ± 0.26, 1.12 ± 0.55, and 1.04 ± 0.28 for HDHS, LDHS, and controls, respectively, P > 0.05). There was no significant between group differences for any ε parameter.

CONCLUSION

Bi-atrial hypertrophy is demonstrated in HDHS athletes and not in LDHS athletes, suggesting that the dynamic component to training is the primary driver for both LA and RA adaptation. Although functional data derived from volume shifts suggest augmented function in HDHS athletes, MST imaging demonstrated no difference in intrinsic atrial ε in any of the groups.

Acute versus chronic exercise-induced left-ventricular remodeling

Exercise-induced cardiac remodeling (EICR) is the process by which the heart adapts to the physiologic stress of exercise. Non-invasive cardiovascular imaging has led to advances in the understanding of EICR, with sport-specific changes in left-ventricular (LV) structure and function being described; however, the majority of data stem from cross-sectional and short-duration longitudinal studies. Due to the paucity of long-term longitudinal EICR studies, the time course of this process and any distinct differentiation between acute and chronic adaptations remain largely unexplored. In order to clarify the natural history of EICR, longer duration longitudinal study is required. Such work will determine whether exercise-induced changes in myocardial structure and function occur in discrete stages. Examination of prolonged exposures to exercise training will also be necessary to determine normative values across the age and training spectrums of athletic patients. This information will help to distinguish the boundary between physiology and pathology in athletic patients.