Exercise-Induced Cardiac Troponin I Increase and Incident Mortality and Cardiovascular Events.

BACKGROUND: Blood concentrations of cardiac troponin above the 99th percentile are a key criterion for the diagnosis of acute myocardial injury and infarction. Troponin concentrations, even below the 99th percentile, predict adverse outcomes in patients and the general population. Elevated troponin concentrations are commonly observed after endurance exercise, but the clinical significance of this increase is unknown. We examined the association between postexercise troponin I concentrations and clinical outcomes in long-distance walkers. METHODS: We measured cardiac troponin I concentrations in 725 participants (61 [54-69] yrs) before and immediately after 30 to 55 km of walking. We tested for an association between postexercise troponin I concentrations above the 99th percentile (>0.040 µg/L) and a composite end point of all-cause mortality and major adverse cardiovascular events (myocardial infarction, stroke, heart failure, revascularization, or sudden cardiac arrest). Continuous variables were reported as mean ± standard deviation when normally distributed or median [interquartile range] when not normally distributed. RESULTS: Participants walked 8.3 [7.3-9.3] hours at 68±10% of their maximum heart rate. Baseline troponin I concentrations were >0.040 µg/L in 9 participants (1%). Troponin I concentrations increased after walking (P<.001), with 63 participants (9%) demonstrating a postexercise troponin concentration >0.040 µg/L. During 43 [23-77] months of follow-up, 62 participants (9%) experienced an end point; 29 died and 33 had major adverse cardiovascular events. Compared with 7% with postexercise troponin I ≤0.040 µg/L (log-rank P<.001), 27% of participants with postexercise troponin I concentrations >0.040 µg/L experienced an end point. The hazard ratio was 2.48 (95% CI, 1.29-4.78) after adjusting for age, sex, cardiovascular risk factors (hypertension, hypercholesterolemia or diabetes mellitus), cardiovascular diseases (myocardial infarction, stroke, or heart failure), and baseline troponin I concentrations. CONCLUSIONS: Exercise-induced troponin I elevations above the 99th percentile after 30 to 55 km of walking independently predicted higher mortality and cardiovascular events in a cohort of older long-distance walkers. Exercise-induced increases in troponin may not be a benign physiological response to exercise, but an early marker of future mortality and cardiovascular events.

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.

Scaling of cardiac morphology is interrupted by birth in the developing sheep Ovis aries.

Scaling of the heart across development can reveal the degree to which variation in cardiac morphology depends on body mass. In this study, we assessed the scaling of heart mass, left and right ventricular masses, and ventricular mass ratio, as a function of eviscerated body mass across fetal and postnatal development in Horro sheep Ovis aries (~50-fold body mass range; N = 21). Whole hearts were extracted from carcasses, cleaned, dissected into chambers and weighed. We found a biphasic relationship when heart mass was scaled against body mass, with a conspicuous 'breakpoint' around the time of birth, manifest not by a change in the scaling exponent (slope), but rather a jump in the elevation. Fetal heart mass (g) increased with eviscerated body mass (Mb , kg) according to the power equation 4.90 Mb0.88 ± 0.26 (± 95%CI) , whereas postnatal heart mass increased according to 10.0 Mb0.88 ± 0.10 . While the fetal and postnatal scaling exponents are identical (0.88) and reveal a clear dependence of heart mass on body mass, only the postnatal exponent is significantly less than 1.0, indicating the postnatal heart becomes a smaller component of body mass as the body grows, which is a pattern found frequently with postnatal cardiac development among mammals. The rapid doubling in heart mass around the time of birth is independent of any increase in body mass and is consistent with the normalization of wall stress in response to abrupt changes in volume loading and pressure loading at parturition. We discuss variation in scaling patterns of heart mass across development among mammals, and suggest that the variation results from a complex interplay between hard-wired genetics and epigenetic influences.

Athletic Remodeling in Female College Athletes: The "Morganroth Hypothesis" Revisited.

BACKGROUND: There is limited data regarding ventricular remodeling in college female athletes, especially when appropriate scaling of cardiac dimensions to lean body mass (LBM) is considered. Moreover, it is not well established whether cardiac remodeling in female athletes is a balanced process with proportional increase in left ventricular (LV) mass and volume or the right and LV size. METHODS: During the preparticipation competitive screening, 72 female college athletes volunteered to undergo dual energy x-ray absorptiometry scan for quantification of LBM and comprehensive 2D echocardiography including assessment of longitudinal myocardial strain. The athletes were divided in 2 groups according to the intensity of the dynamic and static components of their sport categories, ie, a higher intensity dynamic and resistive group (n = 37 participating in rowing, water polo and lacrosse) and a lower intensity group (n = 35, participating in short distance running, sailing, synchronized swimming, and softball). In addition, we recruited a group of 31 age-matched nonathlete controls. RESULTS: The mean age of the study population was 18.7 ± 1.0 years. When scaled to body surface area, the higher intensity group had 17.1 ± 3.6% (P < 0.001) greater LV mass when compared with the lower intensity group and 21.7 ± 4.0% (P < 0.001) greater LV mass than the control group. The differences persisted after scaling to LBM with 14.2 ± 3.2% (P < 0.001) greater LV mass in the higher intensity group. By contrast, there was no difference in any of the relative remodeling indices including the LV mass to volume ratio, right to LV area ratio, or left atrial to LV volume ratio (P > 0.50 for all). In addition, no significant difference was noted among the 3 groups in LV ejection fraction (P = 0.22), LV global longitudinal strain (P = 0.55), LV systolic strain rate (P = 0.62), or right ventricular global longitudinal strain (P = 0.61). CONCLUSION: Female collegiate athletes participating in higher intensity dynamic and resistive sports have higher indexed LV mass even when scaled to LBM. The remodeling process does however appear to be a balanced process not only at the intraventricular level but also at the interventricular and atrioventricular levels.

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 twist n = 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.

Electrical and structural adaptations of the paediatric athlete's heart: a systematic review with meta-analysis.

AIM: To describe the electrocardiographic (ECG) and echocardiographic manifestations of the paediatric athlete's heart, and examine the impact of age, race and sex on cardiac remodelling responses to competitive sport. DESIGN: Systematic review with meta-analysis. DATA SOURCES: Six electronic databases were searched to May 2016: MEDLINE, PubMed, EMBASE, Web of Science, CINAHL and SPORTDiscus. INCLUSION CRITERIA: (1) Male and/or female competitive athletes, (2) participants aged 6-18 years, (3) original research article published in English language. RESULTS: Data from 14 278 athletes and 1668 non-athletes were included for qualitative (43 articles) and quantitative synthesis (40 articles). Paediatric athletes demonstrated a greater prevalence of training-related and training-unrelated ECG changes than non-athletes. Athletes ≥14 years were 15.8 times more likely to have inferolateral T-wave inversion than athletes <14 years. Paediatric black athletes had significantly more training-related and training-unrelated ECG changes than Caucasian athletes. Age was a positive predictor of left ventricular (LV) internal diameter during diastole, interventricular septum thickness during diastole, relative wall thickness and LV mass. When age was accounted for, these parameters remained significantly larger in athletes than non-athletes. Paediatric black athletes presented larger posterior wall thickness during diastole (PWTd) than Caucasian athletes. Paediatric male athletes also presented larger PWTd than females. CONCLUSIONS: The paediatric athlete's heart undergoes significant remodelling both before and during 'maturational years'. Paediatric athletes have a greater prevalence of training related and training-unrelated ECG changes than non-athletes, with age, race and sex mediating factors on cardiac electrical and LV structural remodelling.

The CHANGE! Project: Changes in Body Composition and Cardiorespiratory Fitness in 10- to 11-Year-Old Children After Completing the CHANGE! Intervention.

PURPOSE: To assess the effects of the Children's Health, Activity and Nutrition: Get Educated! intervention on body size, body composition, and peak oxygen uptake in a subsample of 10- to 11-year-old children. METHODS: Sixty children were recruited from 12 schools (N = 6 intervention) to take part in the CHANGE! subsample study. Baseline, postintervention, and follow-up measures were completed in October 2010, March-April 2011, and June-July 2011, respectively. Outcome measures were body mass index z score, waist circumference, body composition assessed using dual-energy X-ray absorptiometry (baseline and follow-up only), and peak oxygen uptake. RESULTS: Significant differences in mean trunk fat mass (control = 4.72 kg, intervention = 3.11 kg, P = .041) and trunk fat % (control = 23.08%, intervention = 17.75%, P = .022) between groups were observed at follow-up. Significant differences in waist circumference change scores from baseline to follow-up were observed between groups (control = 1.3 cm, intervention = -0.2 cm, P = .023). Favorable changes in body composition were observed in the intervention group; however, none of these changes reached statistical significance. No significant differences in peak oxygen uptake were observed. CONCLUSIONS: The results of the present study suggest the multicomponent curriculum intervention had small to medium beneficial effects on body size and composition health outcomes.

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.

Cardiovascular benefits and risks across the physical activity continuum.

PURPOSE OF REVIEW: Habitual physical activity can reduce the risk of future cardiovascular morbidity and mortality. This review evaluates recent publications that have assessed the impact of the dose of physical (in)activity on cardiovascular outcomes. RECENT FINDINGS: Sedentary behavior, characterized by prolonged sitting, is increasingly prevalent across the globe and increases the risk for cardiovascular events in a dose-dependent fashion. Similarly, the number of individuals performing endurance exercise events has tripled over the last 2 decades, and some studies suggest that the high volumes of exercise training and competition may attenuate the health benefits of a physically active lifestyle. SUMMARY: Breaking up sitting time or replacing sitting by (light) physical activity are effective strategies to attenuate its detrimental health effects. Low doses of physical activity, preferably at a high intensity, significantly reduce the risk for cardiovascular and all-cause mortality. Larger doses of exercise yield larger health benefits. Extreme doses of exercise neither increase nor decrease the risk for adverse outcomes. Athletes demonstrate a transient cardiac dysfunction and biomarker release directly postexercise. Chronic exercise training may increase the risk for atrial fibrillation, but is also associated with a superior life expectancy compared with the general population.

Reproducibility of cardiac biomarkers response to prolonged treadmill exercise.

We examined the reproducibility of alterations in cardiac biomarkers after two identical bouts of prolonged exercise in young athletes. Serum high-sensitivity cardiac troponin T (hs-cTnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were assessed before and after exercise. Significant rises in median hs-cTnT and NT-proBNP occurred in both trials. While the absolute changes in hs-cTnT were smaller after trial 2, the pattern of change was similar and the delta scores were significantly related. However, the change in NT-proBNP was not correlated between trials. The hs-cTnT release demonstrates some consistency after exercise although the blunted hc-cTnT response requires further study.

ECG and morphologic adaptations in Arabic athletes: are the European Society of Cardiology's recommendations for the interpretation of the 12-lead ECG appropriate for this ethnicity?

AIMS: To examine the cardiac structure and function of Arabic athletes and to establish if the European Society of Cardiology (ESC) guidelines for the interpretation of an athlete's ECG are applicable to this ethnicity. METHODS: 600 high-level Arabic, 415 Black African, 160 Caucasian male athletes (exercising ≥6 h/week) and 201 Arabic controls presented for ECG and echocardiographic screening. RESULTS: 9 athletes (0.7%) were identified with a cardiac pathology associated with sudden cardiac death. Two Arabics (0.3%) and five Black Africans (1.2%) were diagnosed with hypertrophic cardiomyopathy; a prevalence four times greater in Black African compared to Arabic athletes. Arabic athletes had significantly greater (p<0.05) left ventricular (LV) end-diastolic diameters, maximal LV wall thicknesses and LV mass compared with controls; yet were significantly smaller than Black African and Caucasian athletes. The percentage of athletes demonstrating LV hypertrophy (≥12 mm) was comparable between Arabic, Black African and Caucasian populations (0.5%, 0.5% and 0.6%, respectively). There was no difference in the frequency of an uncommon and training-unrelated ECG between Arabic and Caucasian. However, Black Africans demonstrated a significantly greater prevalence than Arabic and Caucasian athletes (20% vs 8.4% and 6.9%, p<0.001); specifically more right/left atrial enlargement and T wave inversion. CONCLUSIONS: Arabic athletes present significantly smaller cardiac dimensions than Black African and Caucasian athletes. There was no significant difference between the frequency of an uncommon and training-unrelated ECG between Arabic and Caucasian athletes. Therefore, the use of ESC guidelines for the interpretation of an athlete's ECG is clinically relevant and acceptable for use within Arabic athletes.

Allometric scaling for left ventricular mass and geometry in male and female athletes of mixed and endurance sports.

BACKGROUND: The athlete's heart (AH) defines the phenotypical changes that occur in response to chronic exercise training. Echocardiographic assessment of the AH is used to calculate LV mass (LVM) and determine chamber geometry. This is, however, interpreted using standard linear (ratiometric) scaling to body surface area (BSA) whereas allometric scaling is now widely recommended. This study (1) determined whether ratiometric scaling of LVM to BSA (LVMiratio) provides a size-independent index in young and veteran athletes of mixed and endurance sports (MES), and (2) calculated size-independent beta exponents for allometrically derived (LVMiallo) to BSA and (3) describes the physiological range of LVMiallo and the classifications of LV geometry. METHODS: 1373 MES athletes consisting of young (< 35 years old) (males n = 699 and females n = 127) and veteran (> 35 years old) (males n = 327 and females n = 220) were included in the study. LVMiratio was calculated as per standard scaling and sex-specific LVMiallo were derived from the population. Cut-offs were defined and geometry was classified according to the new exponents and relative wall thickness. RESULTS: LVMiratio did not produce a size independent index. When tested across the age range the following indexes LVMi/BSA0.7663 and LVMi/BSA0.52, for males and females respectively, were size independent (r = 0.012; P = 0.7 and r = 0.003; P = 0.920). Physiological cut-offs for LVMiallo were 135 g/(m2)0.7663 in male athletes and 121 g/(m2)0.52 in female athletes. Concentric remodelling / hypertrophy was present in 3% and 0% of young male and female athletes and 24% and 17% of veteran male and female athletes, respectively. Eccentric hypertrophy was observed in 8% and 6% of young male and female athletes and 9% and 11% of veteran male and female athletes, respectively. CONCLUSION: In a large cohort of young and veteran male and female MES athletes, LVMiratio to BSA is not size independent. Sex-specific LVMiallo to BSA with LVMi/BSA0.77 and LVMi/BSA0.52 for male and female athletes respectively can be applied across the age-range. Population-based cut-offs of LVMiallo provided a physiological range demonstrating a predominance for normal geometry in all athlete groups with a greater percentage of concentric remodelling/hypertrophy occurring in veteran male and female athletes.

A multi-method exploration of a cardiac rehabilitation service delivered by registered Clinical Exercise Physiologists in the UK: key learnings for current and new services.

BACKGROUND: Cardiac rehabilitation has been identified as having the most homogenous clinical exercise service structure in the United Kingdom (UK), but inconsistencies are evident in staff roles and qualifications within and across services. The recognition of Clinical Exercise Physiologists (CEPs) as a registered health professional in 2021 in the UK, provides a potential solution to standardise the cardiac rehabilitation workforce. This case study examined, in a purposefully selected cardiac exercise service that employed registered CEPs, (i) how staff knowledge, skills and competencies contribute to the provision of the service, (ii) how these components assist in creating effective service teams, and (iii) the existing challenges from staff and patient perspectives. METHODS: A multi-method qualitative approach (inc., semi-structured interviews, observations, field notes and researcher reflections) was employed with the researcher immersed for 12-weeks within the service. The Consolidated Framework for Implementation Research was used as an overarching guide for data collection. Data derived from registered CEPs (n = 5), clinical nurse specialists (n = 2), dietitians (n = 1), service managers/leads (n = 2) and patients (n = 7) were thematically analysed. RESULTS: Registered CEPs delivered innovative exercise prescription based on their training, continued professional development (CPD), academic qualifications and involvement in research studies as part of the service. Exposure to a wide multidisciplinary team (MDT) allowed skill and competency transfer in areas such as clinical assessments. Developing an effective behaviour change strategy was challenging with delivery of lifestyle information more effective during less formal conversations compared to timetabled education sessions. CONCLUSIONS: Registered CEPs have the specialist knowledge and skills to undertake and implement the latest evidence-based exercise prescription in a cardiac rehabilitation setting. An MDT service structure enables a more effective team upskilling through shared peer experiences, observations and collaborative working between healthcare professionals.

Insights and recommendations into service model structure, staff roles and qualifications in a UK cancer specific clinical exercise service: a multi-method qualitative study.

PURPOSE: Clinical exercise delivery in the United Kingdom is disparate in terms of service structure, staff roles and qualifications, therefore it is difficult to evaluate and compare across services. Our aim was to explore, in a purposely selected cancer exercise service that was recognised as effective; (i) how staff knowledge, skills and competencies contribute to the provision of the service, (ii) how these components assist in creating effective services, and (iii) to identify existing challenges from staff and service user perspectives. METHODS: The Consolidated Framework for Implementation Research was used as an overarching guide to review the Prehab4Cancer service. Exercise specialists and service user perspectives were explored using a multi-method approach (online semi-structured interviews, online focus group and in-person observation) and data triangulation. RESULTS: Exercise specialists were educated to a minimum of undergraduate degree level with extensive cancer-specific knowledge and skills, equivalent to that of a Registration Council for Exercise Physiologist (RCCP) Clinical Exercise Physiologist. Workplace experience was essential for exercise specialist development in behaviour change and communications skills. CONCLUSIONS: Staff should be educated to a level comparable with the standards for registered RCCP Clinical Exercise Physiologists, which includes workplace experience to develop knowledge, skills and competencies in real-world settings.

Cancer servicesClinical exercise staff should attain extensive cancer-specific knowledge, skills and competencies, underpinned by undergraduate degrees in sport and exercise science-related subjects or higher and equivalent to that of Registration Council for Exercise Physiologist -registered Clinical ExerciseWorkplace experience is vital for exercise specialists to develop their knowledge, skills and competencies in real-world settings.Behaviour change and communication skills, specifically empathy and listening skills, should be incorporated into clinical exercise practitioner training.

The impact of image and performance enhancing drugs on atrial structure and function in resistance trained individuals.

BACKGROUND: Image and performance enhancing drugs (IPEDs) are commonly used in resistance trained (RT) individuals and negatively impact left ventricular (LV) structure and function. Few studies have investigated the impact of IPEDs on atrial structure and function with no previous studies investigating bi-atrial strain. Additionally, the impact of current use vs. past use of IPEDs is unclear. METHODS: Utilising a cross-sectional design, male (n = 81) and female (n = 15) RT individuals were grouped based on IPED user status: current (n = 57), past (n = 19) and non-users (n = 20). Participants completed IPED questionnaires, anthropometrical measurements, electrocardiography, and transthoracic echocardiography with strain imaging. Structural cardiac data was allometrically scaled to body surface area (BSA) according to laws of geometric similarity. RESULTS: Body mass and BSA were greater in current users than past and non-users of IPEDs (p < 0.01). Absolute left atrial (LA) volume (60 ± 17 vs 46 ± 12, p = 0.001) and right atrial (RA) area (19 ± 4 vs 15 ± 3, p < 0.001) were greater in current users than non-users but this difference was lost following scaling (p > 0.05). Left atrial reservoir (p = 0.008, p < 0.001) and conduit (p < 0.001, p < 0.001) strain were lower in current users than past and non-users (conduit: current = 22 ± 6, past = 29 ± 9 and non-users = 31 ± 7 and reservoir: current = 33 ± 8, past = 39 ± 8, non-users = 42 ± 8). Right atrial reservoir (p = 0.015) and conduit (p = 0.007) strain were lower in current than non-users (conduit: current = 25 ± 8, non-users = 33 ± 10 and reservoir: current = 36 ± 10, non-users = 44 ± 13). Current users showed reduced LV diastolic function (A wave: p = 0.022, p = 0.049 and E/A ratio: p = 0.039, p < 0.001) and higher LA stiffness (p = 0.001, p < 0.001) than past and non-users (A wave: current = 0.54 ± 0.1, past = 0.46 ± 0.1, non-users = 0.47 ± 0.09 and E/A ratio: current = 1.5 ± 0.5, past = 1.8 ± 0.4, non-users = 1.9 ± 0.4, LA stiffness: current = 0.21 ± 0.7, past = 0.15 ± 0.04, non-users = 0.15 ± 0.07). CONCLUSION: Resistance trained individuals using IPEDs have bi-atrial enlargement that normalises with allometric scaling, suggesting that increased size is, in part, associated with increased body size. The lower LA and RA reservoir and conduit strain and greater absolute bi-atrial structural parameters in current than non-users of IPEDs suggests pathological adaptation with IPED use, although the similarity in these parameters between past and non-users suggests reversibility of pathological changes with withdrawal.

The athlete's heart: insights from echocardiography.

The manifestations of the athlete's heart can create diagnostic challenges during an echocardiographic assessment. The classifications of the morphological and functional changes induced by sport participation are often beyond 'normal limits' making it imperative to identify any overlap between pathology and normal physiology. The phenotype of the athlete's heart is not exclusive to one chamber or function. Therefore, in this narrative review, we consider the effects of sporting discipline and training volume on the holistic athlete's heart, as well as demographic factors including ethnicity, body size, sex, and age.

A New Tool to Aid the Differential Diagnosis of Physiological Remodelling from Cardiac Pathology When Assessing Left Ventricle, Left Atrial and Aortic Structure and Function in Male Arab and Black Paediatric Athletes.

Aim: To determine if published Z-scores for left ventricular (LV), left atrial (LA) and aortic structure as well as indices of LV function (Doppler and TDI) in paediatric athletes and non-athletes are appropriate for application in male Arab and black paediatric athletes. If inappropriate, we aim to provide new nomograms and Z-scores for clinical application. Methods: 417 (297 Arab, 120 black) male paediatric (11-18 years) athletes, were evaluated by 2D echocardiography as per British Society of Echocardiography recommendations, and biological age (by radiological X-ray) assessment. Z-scores were tested by residual and correlation analysis together with visual inspection. New Z-scores involved allometric (a*BSA(b+c*chronological age)) and second-order polynomial (y=a*chronological age2+b*chronological age+c) equations for measures of cardiac size and indices of LV function, respectively. Results: Residual linear regression, correlation analysis and visual inspection revealed published z-scores in white peri-pubertal footballers and paediatric non-athletes to be inappropriate for application in male Arab and black paediatric athletes. Residual linear regression revealed new Z-scores for measures of LV, LA and aortic root size to be independent of BSA, ethnicity, chronological and biological age. Residual linear regression revealed new Z-scores for measures of function to be independent of chronological age. Conclusion: Our new z-scores may aid differential diagnosis of suspected pathology versus physiology remodelling, in cardiac screening of the Arab and black paediatric athlete. Nomograms are provided to assist the tracking of the paediatric athlete necessitating annual follow-up and Excel z-score calculation to facilitate use in day-to-day practice.

Endurance exercise training enhances cutaneous microvascular reactivity in post-menopausal women.

OBJECTIVE: To compare cutaneous microvascular reactivity between untrained young and post-menopausal women, and assess the effects of 48 weeks of endurance exercise training on cutaneous microvascular reactivity in post-menopausal women. METHODS: Twenty post-menopausal and 12 young women completed this study. Using laser-Doppler flowmetry, an index of skin blood flow was measured on the forearm at rest, during post-occlusive reactive hyperaemia (PORH), and during localised heating to 42°C. Cutaneous vascular conductance (CVC) was calculated as the ratio of laser-Doppler flow to mean arterial pressure (in AU mm Hg(-1)). For the post-menopausal women, this assessment was also performed after 6, 12, 24, 36, and 48 weeks of endurance exercise training. RESULTS: PORH and maximum CVC responses were depressed in untrained post-menopausal women compared with young controls (P ≤ 0.011 for all methods of data expression). PORH was increased (P<0.05) in the post-menopausal women after 24 weeks of exercise training (0.51 ± 0.16 vs. 0.65 ± 0.23 AU mm Hg(-1)), with further increases after 36 and 48 weeks (0.76 ± 0.27 and 0.88 ± 0.32 AU mm Hg(-1), respectively). Similarly, maximum CVC was increased (P<0.05) after 24 weeks (2.20 ± 0.31 vs. 2.66 ± 0.27 AU mm Hg(-1)), and at the 36-week assessment (2.90 ± 0.30 AU mm Hg(-1)). Cardiopulmonary fitness (V˙O(2)max) increased after 12 weeks (23.5 ± 4.4 vs. 25.4 ± 5.1 mL kg(-1)min(-1); P<0.05), and improved further throughout the intervention (31.6 ± 5.9 mL kg(-1)min(-1) at week 48). There was a moderate positive relationship between the change in PORH (in AU mm Hg(-1)) between weeks 0 and 48 and the concomitant change in V˙O(2)max (r=0.65, P=0.002). After 24-36 weeks of exercise training, the PORH and maximum CVC responses of the post-menopausal women did not differ to those of the young untrained women (P>0.05). CONCLUSION: Cutaneous microvascular reactivity is reduced in post-menopausal women compared to young controls and increased to similar levels after 24-36 weeks of mild-to-moderate endurance exercise.

Do big athletes have big hearts? Impact of extreme anthropometry upon cardiac hypertrophy in professional male athletes.

AIM: Differentiating physiological cardiac hypertrophy from pathology is challenging when the athlete presents with extreme anthropometry. While upper normal limits exist for maximal left ventricular (LV) wall thickness (14 mm) and LV internal diameter in diastole (LVIDd, 65 mm), it is unknown if these limits are applicable to athletes with a body surface area (BSA) >2.3 m(2). PURPOSE: To investigate cardiac structure in professional male athletes with a BSA>2.3 m(2), and to assess the validity of established upper normal limits for physiological cardiac hypertrophy. METHODS: 836 asymptomatic athletes without a family history of sudden death underwent ECG and echocardiographic screening. Athletes were grouped according to BSA (Group 1, BSA>2.3 m(2), n=100; Group 2, 2-2.29 m(2), n=244; Group 3, <1.99 m(2), n=492). RESULTS: There was strong linear relationship between BSA and LV dimensions; yet no athlete with a normal ECG presented a maximal wall thickness and LVIDd greater than 13 and 65 mm, respectively. In Group 3 athletes, Black African ethnicity was associated with larger cardiac dimensions than either Caucasian or West Asian ethnicity. Three athletes were diagnosed with a cardiomyopathy (0.4% prevalence); with two athletes presenting a maximal wall thickness >13 mm, but in combination with an abnormal ECG suspicious of an inherited cardiac disease. CONCLUSION: Regardless of extreme anthropometry, established upper limits for physiological cardiac hypertrophy of 14 mm for maximal wall thickness and 65 mm for LVIDd are clinically appropriate for all athletes. However, the abnormal ECG is key to diagnosis and guides follow-up, particularly when cardiac dimensions are within accepted limits.