RV Remodeling in Olympic Athletes

Apicolateral bulge: A potential mimic of arrhythmogenic right ventricular cardiomyopathy in a professional athlete-A case report and literature review

Soccer is the most popular sport in the world, with over 265 million active players and approximately 0.05% professional players worldwide. The Fédération Internationale de Football Association (FIFA) has made preparticipation screening recommendations which involve electrocardiography and echocardiography being performed prior to international competition. The aim of preparticipation cardiovascular screening in young athletes is to detect asymptomatic individuals with cardiovascular disease at risk of sudden cardiac death (SCD). The incidence of SCD in young athletes (age≤ 35 years) is 0.6-3.6 in 100,000 persons/year, with most deaths due to cardiovascular causes. Arrhythmogenic right ventricular cardiomyopathy (ARVC) is one of the leading causes of SCD in young athletes. It is a genetic disease characterized by progressive fibrofatty replacement of the myocardium with variable phenotypic expression. Exercise-induced cardiac remodeling in conjunction with extensive T-wave inversion raises concern for ARVC. This case report and literature review explores a potential mimic for ARVC, the role of cardiovascular screening in sport, and the use of a multimodality approach for risk stratification and management.

The Role of Cardiovascular Imaging in the Diagnosis of Athlete's Heart: Navigating the Shades of Grey

Athlete's heart (AH) represents the heart's remarkable ability to adapt structurally and functionally to prolonged and intensive athletic training. Characterized by increased left ventricular (LV) wall thickness, enlarged cardiac chambers, and augmented cardiac mass, AH typically maintains or enhances systolic and diastolic functions. Despite the positive health implications, these adaptations can obscure the difference between benign physiological changes and early manifestations of cardiac pathologies such as dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), and arrhythmogenic cardiomyopathy (ACM). This article reviews the imaging characteristics of AH across various modalities, emphasizing echocardiography, cardiac magnetic resonance (CMR), and cardiac computed tomography as primary tools for evaluating cardiac function and distinguishing physiological adaptations from pathological conditions. The findings highlight the need for precise diagnostic criteria and advanced imaging techniques to ensure accurate differentiation, preventing misdiagnosis and its associated risks, such as sudden cardiac death (SCD). Understanding these adaptations and employing the appropriate imaging methods are crucial for athletes' effective management and health optimization.

The differentiation of the competitive athlete with physiologic cardiac remodeling from the athlete with cardiomyopathy

There are currently 5 million active high school, collegiate, professional, and master athletes in the United States. Regular intense exercise by these athletes can promote structural, electrical and functional remodeling of the heart, which is termed the "athlete's heart." In addition, regular intense exercise can lead to pathological adaptions that promote or worsen cardiac disease. Many of the athletes in the United States seek medical care. Consequently, physicians must be aware of the normal cardiac anatomy and physiology of the athlete, the differentiation of the normal athlete heart from the athlete with cardiomyopathy, and the contemporary care of the athlete with a cardiomyopathy. In athletes with persistent cardiovascular symptoms, investigations should include a detailed history and physical examination, an ECG, a transthoracic echocardiogram, and in athletes in whom the diagnosis is uncertain, a maximal exercise stress test or a continuous ECG recording, and cardiac magnetic resonance imaging or cardiac computed tomography angiography when definition of the coronary anatomy or characterization of the aorta and the aortic great vessels is indicated. This article discusses the differentiation of the normal athlete with physiologic cardiac remodeling from the athlete with hypertrophic, dilated or arrhythmogenic ventricular cardiomyopathy (ACM). The ECG changes in trained athletes that are considered normal, borderline, or abnormal are listed. In addition, the normal echocardiographic measurements for athletes who consistently participate in endurance, power, combined or heterogeneous sports are enumerated and discussed. Algorithms are listed that are useful in the diagnosis of trained athletes with borderline or abnormal echocardiographic measurements suggestive of cardiomyopathies along with the major and minor criteria for the diagnosis of ACM in athletes. Thereafter, the treatment of athletes with hypertrophic, dilated, and arrhythmogenic right ventricular cardiomyopathies are reviewed. The distinction between physiologic changes and pathologic changes in the hearts of athletes has important therapeutic and prognostic implications. Failure by the physician to correctly diagnose an athlete with hypertrophic cardiomyopathy, dilated cardiomyopathy, or ACM, can lead to the sudden cardiac arrest and death of the athlete during training or sports competition. Conversely, an incorrect diagnosis by a physician of cardiac pathology in a normal athlete can lead to an unnecessary restriction of athlete training and competition with resultant significant emotional, psychological, financial, and long-term health consequences in the athlete.

The athlete's heart: allometric considerations on published papers and relation to cardiovascular variables

To evaluate the morphology of the "athlete's heart", left ventricular (LV) wall thickness (WT) and end-diastolic internal diameter (LVIDd) at rest were addressed in publications on skiers, rowers, swimmers, cyclists, runners, weightlifters (n = 927), and untrained controls (n = 173) and related to the acute and maximal cardiovascular response to their respective disciplines. Dimensions of the heart at rest and functional variables established during the various sport disciplines were scaled to body weight for comparison among athletes independent of body mass. The two measures of LV were related (r = 0.8; P = 0.04) across athletic disciplines. With allometric scaling to body weight, LVIDd was similar between weightlifters and controls but 7%-15% larger in the other athletic groups, while WT was 9%-24% enlarged in all athletes. The LVIDd was related to stroke volume, oxygen pulse, maximal oxygen uptake, cardiac output, and blood volume (r =  ~ 0.9, P < 0.05), while there was no relationship between WT and these variables (P > 0.05). In conclusion, while cardiac enlargement is, in part, essential for the generation of the cardiac output and thus stroke volume needed for competitive endurance exercise, an enlarged WT seems important for the development of the wall tension required for establishing normal arterial pressure in the enlarged LVIDd.

Influence of isometric versus isotonic exercise training on right ventricular morpho-functional parameters in Olympic athletes

BACKGROUND

Cardiovascular adaptations in elite athletes involve both ventricular and atrial changes. Nowadays, limited research exists on right ventricular (RV) remodeling, particularly in female athletes and across different types of exercise training.

METHODS

Our study evaluated 370 athletes (61% males) participated at 2020 Tokyo and 2022 Beijing Olympic Games. Athletes were categorized according to main type of exercise into isometric and isotonic. Comprehensive echocardiographic assessments were conducted to analyze RV morpho-functional parameters, comparing genders and different sporting exercise.

RESULTS

Significant differences in RV parameters were observed based on exercise type and gender. Isotonic athletes showed greater RV remodeling with larger RV outflow tract (15.1 ± 2.1 vs. 14.5 ± 1.7 mm, p < .0001) end-diastolic and end-systolic area (respectively, 24.6 ± 5.5 vs. 21.7 ± 5 mm, p < .000 and 11.7 ± 3.2 vs. 10.1 ± 2.8 mm, p < .0001) and right atrium size (11.7 ± 3.2 vs. 10.2 ± 2.3 mm2 , p = .0001). Functional parameters, such as TDI velocities, were similar between groups. Males showed larger RV area and right atrium size (p < .0001) and lower RV TDI velocities with reduced E' (15.4 ± 2.9 vs. 16.1 ± 3.2 m/s in females, p = .031), resulting in lower E'/A' ratio (1.69 ± .6 vs. 1.84 ± .6 m/s, p = .021), while S' was lower females (14.6 ± 2.3 vs. 14.1 ± 2.4 m/s, p = .041). RV TDI velocities were similar in isotonic and isometric both in male and females.

CONCLUSIONS

In elite athletes, RV morphological changes are influenced by exercise modality but do not translate into functional differences. Female athletes present distinct RV functional profiles, with lower S' velocities and a higher E'/A' ratio. Functional RV TDI parameters are not affected by the typology of exercise practiced.

Interpretation and management of premature ventricular beats in athletes: An expert opinion document of the Italian Society of Sports Cardiology (SICSPORT)

Premature ventricular beats (PVBs) are recorded in a sizeable proportion of athletes during pre-participation screening, especially if the evaluation includes both resting and exercise ECG. While in the majority of cases no underlying heart disease is present, in others PVBs may be the sign of a condition at risk of sudden cardiac death, including cardiomyopathies, congenital, coronary artery, heart valves and ion channels diseases. In this expert opinion document of the Italian Society of Sports Cardiology, we propose a multiparametric interpretation approach to PVBs in athletes and a stepwise diagnostic algorithm. The clinical work-up should include the assessment of the probable site of origin based on the ECG pattern of the ectopic QRS and of the arrhythmia behavior (including the number of different PVB morphologies, complexity, response to exercise and reproducibility), as well as first-line tests such as echocardiography. Based on this initial evaluation, most athletes can be reassured of the benign nature of PVBs and cleared for competition under periodical follow-up. However, when the clinical suspicion is high, further investigations with non-invasive (e.g. cardiac magnetic resonance, cardiac computed tomography, genetic testing) and, in very selected cases, invasive (e.g. endocardial voltage mapping and endomyocardial biopsy) tests should be carried out to rule out a high-risk condition. Importantly, such advanced tests should be performed in centers with a consolidated experience not only in the technique, but also in evaluation of athletes.

Aortic root/left ventricular diameters golden ratio in competitive athletes

BACKGROUND

The athlete's heart is a well-known phenomenon characterized by a harmonic remodelling that affects the cardiac chambers. However, whether mild-to-moderate aortic dilatation can be considered normal in athletes is debated. This study aimed to evaluate the ratio between left ventricular (LV) size and aortic dimensions, reporting the normal values of the ratio between the aortic root diameters at the level of the sinuses of Valsalva and LV diameters (AoD/LVEDD ratio) in a wide cohort of competitive athletes.

MATERIALS AND METHODS

Competitive athletes were compared with sedentary subjects and patients with aortic dilatation. 1901 subjects who underwent echocardiography from 2019 to 2022 were retrospectively enrolled: 993 athletes (74% males, mean age 26 ± 7 years), 410 sedentary (74.1% males, mean age 29 ± 11 years) and 498 patients with aortic dilatation (74.3% males, mean age 56 ± 7 years).

RESULTS

Patients with aortic dilatation had both an absolute (39.2 ± 2.4 mm) and indexed (19.4 ± 2.2 mm/m2) aortic diameter larger than athletes (30.6 ± 3.2 mm; 16.1 ± 1.5 mm/m2, p < 0.05) and sedentary subjects (30.5 ± 3.1 mm; 16.5 ± 1.6 mm/m2, p < 0.05), with no differences between athletes and sedentary subjects. The AoD/LVEDD ratio was lower in athletes (0.59 ± 0.06) compared to controls (0.65 ± 0.05, p < 0.05) and patients with aortic dilatation (0.81 ± 0.06, p < 0.05). The patients with aortopathy had the lowest LVEDD/AoD ratio, while competitive athletes had the highest, with values of 1.71 ± 0.16 in the latter (overall p value<0.001).

CONCLUSIONS

In this study, we reported the AoD/LVEDD and LVEDD/AoD ratio values in a cohort of healthy athletes, additional parameters that could help confirm the harmonic remodelling in the athlete's heart.

Effects of a 20-Week High-Intensity Strength Training Program on Muscle Strength Gain and Cardiac Adaptation in Untrained Men: Preliminary Results of a Prospective Longitudinal Study

BACKGROUND

As strength sports gain popularity, there is a growing need to explore the impact of sustained strength training on cardiac biventricular structure and function, an area that has received less attention compared to the well-established physiological cardiac adaptation to endurance training.

OBJECTIVE

This study aims to implement a 20-week high-intensity strength training program to enhance maximal muscle strength and evaluate its impact on cardiac biventricular adaptation in healthy, untrained men.

METHODS

A total of 27 healthy and untrained young men (mean age 22.8, SD 3.2 years) participated in a strength training program designed to increase muscle strength. The training program involved concentric, eccentric, and isometric exercise phases, conducted over a consecutive 20-week time frame with a frequency of 3 weekly training sessions. Participants were evaluated before and after 12 and 20 weeks of training through body composition analysis (bioelectrical impedance), a 12-lead resting electrocardiogram, 3D transthoracic echocardiography, cardiopulmonary exercise testing, and muscle isokinetic dynamometry. The progression of strength training loads was guided by 1-repetition maximum (RM) testing during the training program.

RESULTS

Of the initial cohort, 22 participants completed the study protocol. No injuries were reported. The BMI (mean 69.8, SD 10.8 kg/m² vs mean 72, SD 11 kg/m²; P=.72) and the fat mass (mean 15.3%, SD 7.5% vs mean 16.5%, SD 7%; P=.87) remained unchanged after training. The strength training program led to significant gains in 1-RM exercise testing as early as 4 weeks into training for leg extension (mean 69.6, SD 17.7 kg vs mean 96.5, SD 31 kg; P<.001), leg curl (mean 43.2, SD 9.7 kg vs mean 52.8, SD 13.4 kg; P<.001), inclined press (mean 174.1, SD 41.1 kg vs mean 229.2, SD 50.4 kg; P<.001), butterfly (mean 26.3, SD 6.2 kg vs mean 32.5, SD 6.6 kg; P<.001), and curl biceps on desk (mean 22.9, SD 5.2 kg vs mean 29.6, SD 5.2 kg; P<.001). After 20 weeks, the 1-RM leg curl, bench press, pullover, butterfly, leg extension, curl biceps on desk, and inclined press showed significant mean percentage gains of +40%, +41.1%, +50.3%, +63.5%, +80.1%, +105%, and +106%, respectively (P<.001). Additionally, the isokinetic evaluation confirmed increases in maximal strength for the biceps (+9.2 Nm), triceps (+11.6 Nm), quadriceps (+46.8 Nm), and hamstrings (+25.3 Nm). In this paper, only the training and muscular aspects are presented; the cardiac analysis will be addressed separately.

CONCLUSIONS

This study demonstrated that a short-term high-intensity strength training program was successful in achieving significant gains in muscle strength among previously untrained young men. We intend to use this protocol to gain a better understanding of the impact of high-intensity strength training on cardiac physiological remodeling, thereby providing new insights into the cardiac global response in strength athletes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04187170; https://clinicaltrials.gov/study/NCT04187170.

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.

Assessment of right ventricular structure and systolic function in amateur marathon runners using three-dimensional speckle tracking echocardiography

Prolonged high-intensity endurance exercise has been reported to have adverse effects on the heart, which are further correlated with exercise dose. However, its effect on the right ventricle (RV) of amateur runners is unknown. This study aimed was to evaluate the early right ventricular structure and systolic function of amateur marathon runners by three-dimensional speckle tracking echocardiography (3D-STE), and to further analyze the correlation between relevant parameters and the amount of training. A total of 30 amateur marathon runners (marathon group) and 27 healthy volunteers (control group) were enrolled. Conventional echocardiography combined with 3D-STE was performed in all subjects, and the marathon group was screened by echocardiography a week before a marathon (V1), within 1 h post-marathon (V2), and 4 days post-marathon (V3). RV global longitudinal strain (GLS) and RV end-diastolic volume (EDV) increased significantly in the marathon group compared to the control group (P < 0.05). RV GLS was significantly decreased in the marathon group within 1 h post-marathon (V1: - 26.2 ± 2.5% vs V2: - 23.0 ± 1.6% vs V3: - 25.6 ± 2.6%, P < 0.001). However, there was no significant difference in RV ejection fraction (RVEF) (P > 0.05). The results of the correlation analysis showed that RV EDV and RV end-systolic volume (ESV) were positively correlated with the average training volume (P < 0.001). Multivariate linear regression analysis showed that average training volume was an independent predictor of RV EDV in amateur marathoners (β = 0.642, P < 0.001). The systolic function of the RV was enhanced in amateur marathon runners in the early stage, manifested by an increase in RV EDV. After a long period of high-intensity endurance exercise, RV systolic function will temporarily be reduced. 3D-STE can identify this subclinical change with high sensitivity and provide valuable information to assess the structure and function of RV in amateur marathon runners.

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

AIMS

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

METHODS AND RESULTS

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

CONCLUSIONS

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

Three-dimensional echocardiography of the athlete's heart: a comparison with cardiac magnetic resonance imaging

Three-dimensional echocardiography (3DE) is the most accurate cardiac ultrasound technique to assess cardiac structure. 3DE has shown close correlation with cardiac magnetic resonance imaging (CMR) in various populations. There is limited data on the accuracy of 3DE in athletes and its value in detecting alterations during follow-up. Indexed left and right ventricular end-diastolic volume (LVEDVi, RVEDVi), end-systolic volume, ejection fraction (LVEF, RVEF) and left ventricular mass (LVMi) were assessed by 3DE and CMR in two-hundred and one competitive endurance athletes (79% male) from the Pro@Heart trial. Sixty-four athletes were assessed at 2 year follow-up. Linear regression and Bland-Altman analyses compared 3DE and CMR at baseline and follow-up. Interquartile analysis evaluated the agreement as cardiac volumes and mass increase. 3DE showed strong correlation with CMR (LVEDVi r = 0.91, LVEF r = 0.85, LVMi r = 0.84, RVEDVi r = 0.84, RVEF r = 0.86 p < 0.001). At follow up, the percentage change by 3DE and CMR were similar (∆LVEDVi r = 0.96 bias - 0.3%, ∆LVEF r = 0.94, bias 0.7%, ∆LVMi r = 0.94 bias 0.8%, ∆RVESVi r = 0.93, bias 1.2%, ∆RVEF r = 0.87 bias 0.4%). 3DE underestimated volumes (LVEDVi bias - 18.5 mL/m², RVEDVi bias - 25.5 mL/m²) and the degree of underestimation increased with larger dimensions (Q1vsQ4 LVEDVi relative bias - 14.5 versus - 17.4%, p = 0.016; Q1vsQ4 RVEDVi relative bias - 17 versus - 21.9%, p = 0.005). Measurements of cardiac volumes, mass and function by 3DE correlate well with CMR and 3DE accurately detects changes over time. 3DE underestimates volumes and the relative bias increases with larger cardiac size.

Echocardiographic Evaluation of the Athlete's Heart: Focused Review and Update

PURPOSE OF REVIEW

The athlete's heart exhibits unique structural and functional adaptations in the setting of strenuous and repetitive athletic training which may be similarly found in pathologic states. The purpose of this review is to highlight the morphologic and functional changes associated with the athlete's heart, with a focus upon the insights that echocardiography provides into exercise-induced cardiac remodeling.

RECENT FINDINGS

Recent studies are aiming to investigate the long-term effects and clinical consequences of an athlete's heart. The "gray-zone" continues to pose a clinical challenge and may indicate scenarios where additional imaging modalities, or longitudinal follow-up, provide a definitive answer. Echocardiography is likely to remain the first-line imaging modality for the cardiac evaluation of elite athletes. Multimodality imaging combined with outcome and long-term follow-up studies both during training and after retirement in both men and women may help further clarify the remaining mysteries in the coming years.

Certainties and Uncertainties of Cardiac Magnetic Resonance Imaging in Athletes

Prolonged and intensive exercise induces remodeling of all four cardiac chambers, a physiological process which is coined as the “athlete’s heart”. This cardiac adaptation, however, shows overlapping features with non-ischemic cardiomyopathies, such as dilated, arrhythmogenic and hypertrophic cardiomyopathy, also associated with athlete’s sudden cardiac death. Cardiac magnetic resonance (CMR) is a well-suited, highly reproducible imaging modality that can help differentiate athlete’s heart from cardiomyopathy. CMR allows accurate characterization of the morphology and function of cardiac chambers, providing full coverage of the ventricles. Moreover, it permits an in-depth understanding of the myocardial changes through specific techniques such as mapping or late gadolinium enhancement. In this narrative review, we will focus on the certainties and uncertainties of the role of CMR in sports cardiology. The main aspects of physiological adaptation due to regular and intensive sports activity and the application of CMR in highly trained athletes will be summarized.

The Dysfunctional Right Ventricle in Dilated Cardiomyopathies: Looking from the Right Point of View

Dilated cardiomyopathies (DCMs) are a heterogenous group of primary myocardial diseases, representing one of the leading causes of heart failure, and the main indication for heart transplantation. While the degree of left ventricular dilation and dysfunction are two key determinants of adverse outcomes in DCM patients, right ventricular (RV) remodeling and dysfunction further negatively influence patient prognosis. Consequently, RV functional assessment and diagnosing RV involvement by using an integrative approach based on multimodality imaging is of paramount importance in the evaluation of DCM patients and provides incremental prognostic and therapeutic information. Transthoracic echocardiography remains the first-line imaging modality used for the assessment of the RV, and newer techniques such as speckle-tracking and three-dimensional echocardiography significantly improve its diagnostic and prognostic accuracy. Nonetheless, cardiac magnetic resonance (CMR) is considered the gold standard imaging modality for the evaluation of RV size and function, and all DCM patients should be evaluated by CMR at least once. Accordingly, this review provides a comprehensive overview of the anatomy and function of the RV, and the pathophysiology, diagnosis, and prognostic value of RV dysfunction in DCM patients, based on traditional and novel imaging techniques.

Differentiating Physiology from Pathology: The Gray Zones of the Athlete's Heart

Routine vigorous exercise can lead to electrical, structural, and functional adaptations that can enhance exercise performance. There are several factors that determine the type and magnitude of exercise-induced cardiac remodeling (EICR) in trained athletes. In some athletes with pronounced cardiac remodeling, there can be an overlap in morphologic features with mild forms of cardiomyopathy creating gray zone scenarios whereby distinguishing health from disease can be difficult. An integrated clinical approach that factors athlete-specific characteristics (sex, size, sport, ethnicity, and training history) and findings from multimodality imaging are essential to help make this distinction.

Right heart structure and function in lifelong recreational endurance athletes with and without paroxysmal atrial fibrillation

BACKGROUND

Healthy young athletes adapt to the increased demands of endurance exercise with symmetric cardiac remodeling. Male veteran endurance athletes have an increased risk of atrial fibrillation (AF), and some athletes seem susceptible to changes mimicking arrhythmogenic cardiomyopathy. Intense exercise puts a disproportionate hemodynamic load on the right-sided heart chambers. Despite this, data describing right heart structure and function in older veteran athletes are scarce. We aimed to investigate structural and functional characteristics of the right heart in veteran athletes with and without AF to contribute to the understanding of exercise-induced cardiac remodeling in this group.

METHODS

Three hundred and two male participants, of whom 151 were veteran skiers (62 with paroxysmal AF) and 151 were controls from the general population (62 with paroxysmal AF) underwent an echocardiographic examination in sinus rhythm to evaluate right atrial (RA) and right ventricular (RV) structure and function. While 87 of the participants had never exercised regularly, 50, 43, and 122 men had practiced regular endurance exercise for 1-20, 20-40, and >40 years, respectively.

RESULTS

RA volume and RV size increased with cumulative years of exercise (p<0.001), with a disproportionate increase in RV size compared with left ventricular (LV) size, regardless of AF status (p<0.001). RA and RV function assessed by strain remained similar despite lifelong exposure to endurance exercise. AF was associated with reduced RA strain irrespective of exposure to exercise (p<0.001).

CONCLUSION

RA and RV size and RV/LV ratio showed a dose-response relationship with cumulative years of endurance exercise, whereas RA and RV function did not. Indicating that increasing RV/LV ratio may represent a physiological adaptation to prolonged endurance exercise. AF was associated with reduced RA function, regardless of exposure to exercise, suggesting RA functional parameters are more closely linked to AF than RA size in veteran athletes.

The role of pre-participation cardiac evaluation in the management of an athlete with premature ventricular contraction-induced cardiomyopathy: a case report

Background

Premature ventricular contractions (PVCs) are commonly observed during pre-participation cardiac screening in elite athletes. There is an ongoing debate about the clinical significance of PVCs in athletes and whether burden, morphology, or both should be used to differentiate benign PVCs from PVCs suggestive of cardiac disease.

Case summary

A 28-year-old male athlete was evaluated as part of the pre-participation screening programme. He was asymptomatic, without specific cardiac signs and symptoms. A 12-lead electrocardiogram showed bigeminy PVCs with infundibular morphology and left ventricular outflow tract origin. Left ventricular dilatation and systolic dysfunction without valvular lesions was detected on echocardiography. Cardiac magnetic resonance imaging showed biventricular dilatation and dysfunction without evidence of myocardial fibrosis or fatty infiltration. A 48 h Holter monitoring showed 75191 PVCs (35% of total beats). Radiofrequency ablation was performed, and post-ablation assessments showed no PVCs with normalized ventricular function and dimension.

Discussion

This case demonstrated that a high PVC burden of common morphology does not also represent a benign finding and requires a comprehensive evaluation to rule out any pathological condition. Furthermore, the present case highlights the critical role of pre-participation cardiac evaluation in identifying cardiac disease in asymptomatic athletes.

Rationale and design of the PROspective ATHletic Heart (Pro@Heart) study: long-term assessment of the determinants of cardiac remodelling and its clinical consequences in endurance athletes

Background

Exercise-induced cardiac remodelling (EICR) results from the structural, functional and electrical adaptations to exercise. Despite similar sports participation, EICR varies and some athletes develop phenotypic features that overlap with cardiomyopathies. Training load and genotype may explain some of the variation; however, exercise ‘dose’ has lacked rigorous quantification. Few have investigated the association between EICR and genotype.

Objectives

(1) To identify the impact of training load and genotype on the variance of EICR in elite endurance athletes and (2) determine how EICR and its determinants are associated with physical performance, health benefits and cardiac pathology.

Methods

The Pro@Heart study is a multicentre prospective cohort trial. Three hundred elite endurance athletes aged 14–23 years will have comprehensive cardiovascular phenotyping using echocardiography, cardiac MRI, 12-lead ECG, exercise-ECG and 24-hour-Holter monitoring. Genotype will be determined using a custom cardiomyopathy gene panel and high-density single-nucleotide polymorphism arrays. Follow-up will include online tracking of training load. Cardiac phenotyping will be repeated at 2, 5, 10 and 20 years.

Results

The primary endpoint of the Pro@Heart study is the association of EICR with both training load and genotype. The latter will include rare variants in cardiomyopathy-associated genes and polygenic risk scores for cardiovascular traits. Secondary endpoints are the incidence of atrial and ventricular arrhythmias, physical performance and health benefits and their association with training load and genotype.

Conclusion

The Pro@Heart study is the first long-term cohort study to assess the impact of training load and genotype on EICR.

Trial registration number

NCT05164328; ACTRN12618000716268.

Arrhythmogenesis of Sports: Myth or Reality?

Regular exercise confers health benefits with cardiovascular mortality risk reduction through a variety of mechanisms. At a population level, evidence suggests that undertaking more exercise has greater benefits. In the modern era of sport, there has been an exponential rise in professional and amateur athletes participating in endurance events, with a progressively better understanding of the associated cardiac adaptations, collectively termed 'athletes heart'. However, emerging data raise questions regarding the risk of potential harm from endurance exercise, with an increased risk of arrhythmia from adverse cardiac remodelling. Cross-sectional studies have demonstrated that athletes may exhibit a higher burden of AF, conduction tissue disease, ventricular arrhythmias, a cardiomyopathy-like phenotype and coronary artery disease. In an attempt to separate myth from reality, this review reports on the evidence supporting the notion of 'too much exercise', the purported mechanisms of exercise-induced cardiac arrhythmia and complex interplay with sporting discipline, demographics, genetics and acquired factors.

Arrhythmogenic Right Ventricular Cardiomyopathy and Differential Diagnosis with Diseases Mimicking Its Phenotypes

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited heart muscle disease, which is characterized by fibro-fatty replacement of predominantly the right ventricle (RV). The disease can result in ventricular tachyarrhythmias and sudden cardiac death. Our understanding of the pathophysiology and clinical expressivity of ARVC has been continuously evolving. The diagnosis can be challenging due to its variable expressivity, incomplete penetrance and the lack of specific diagnostic criteria. Idiopathic RV outflow tract tachycardia, Brugada Syndrome, athlete’s heart, dilated cardiomyopathy, myocarditis, cardiac sarcoidosis, congenital aneurysms and diverticula may mimic clinical phenotypes of ARVC. This review aims to provide an update on the differential diagnosis of ARVC.

Running the Risk: Exercise and Arrhythmogenic Cardiomyopathy

Purpose of review

The purpose of this review is to summarize what is known about the relationship between exercise and arrhythmogenic right ventricular cardiomyopathy (ARVC) with regard to disease onset, diagnosis, progression, and clinical severity. This relationship forms the basis of the management recommendations for restricting physical activity in individuals with and at risk for ARVC.

Recent findings

While ARVC can be challenging to diagnose, there are several diagnostic testing and imaging modalities that may help distinguish athletic heart remodeling from ARVC. There is an increased risk of adverse clinical outcomes in ARVC from endurance and competitive sports participation, including a dose-dependent relationship between exercise intensity and risk of disease penetrance and progression.

Summary

High-intensity exercise can lead to earlier disease onset, increased penetrance, and clinical progression among individuals with and at risk for ARVC. Both amount and intensity of exercise are correlated with adverse outcomes, including ventricular arrhythmias and worsening biventricular function. All individuals with and at risk for ARVC should undergo detailed clinical phenotyping and risk stratification to reduce the risk of such outcomes, including sudden cardiac death. Consensus guidelines recommend against participation in competitive or high-intensity and endurance exercise for individuals with and at risk for ARVC.

Exercise and the Female Heart

Female participation in sport has increased sharply during the last few decades, and for the third straight Olympic Games, there were more women than men on the US roster for the 2020 Tokyo Games. Given this, an understanding of the differences between men and women with respect to exercise-induced cardiac remodeling is critical for those caring for female athletes. Recent studies have provided insight into female-specific cardiac remodeling and have enhanced our understanding on the upper limits of cardiac remodeling in female athletes and how these adaptations compare with sedentary females, male athletes, and cardiomyopathies. Female athletes display fewer signs of adaptive remodeling on ECG compared with male athletes. Structurally, male athletes have larger absolute cardiac dimensions, but female athletes have similar or larger chamber size when adjusted for body size. Female athletes have a lower incidence of sudden cardiac arrest or death compared with male athletes in the early competitive years (high school, college, and professional) and in the masters athlete years. In addition, female athletes are less likely to have coronary disease and atrial fibrillation compared with male athletes. Data on longevity indicate that female athletes live longer than their sedentary counterparts. Unlike men, there has been no convincing association of extreme exercise and cardiovascular disease in longer-term endurance female athletes. The underlying mechanisms of these sex-based differences are not very well understood, and future studies are warranted to better understand the mechanisms of cardiac adaptation in female athletes.

Advanced cardiac imaging in athlete's heart: unravelling the grey zone between physiologic adaptation and pathology

Over the last decades, interest toward athlete's heart has progressively increased, leading to improve the knowledge on exercise-induced heart modifications. Sport may act as a trigger for life-threatening arrhythmias in patients with structural or electrical abnormalities, hence requiring to improve the diagnostic capability to differentiate physiological from pathological remodeling. Pathological alterations are often subtle at the initial stages; therefore, the challenge is to promptly identify athletes at risk of sudden cardiac death during the pre-participation screening protocols. Advanced imaging modalities such as coronary computed tomography angiography (CCTA) and cardiac magnetic resonance (CMR) can non-invasively depict coronary vessels and provide a deep morpho-functional and structural characterization of the myocardium, in order to rule out pathological life threatening alterations, which may overlap with athletes' heart remodeling. The purpose of the present narrative review is to provide an overview of most frequent diagnostic challenges, defining the boundaries between athlete's heart remodeling and pathological structural alteration with a focus on the role and importance of CCTA and CMR.

Cardiac structure and function in elite female athletes: A systematic review and meta-analysis

We conducted a meta-analysis to synthesize the best available evidence comparing cardiac biventricular structure and function using cardiac magnetic resonance imaging (CMR) and transthoracic echocardiography (TTE) in elite female athletes and healthy controls (HC). Chronic exposure to exercise may induce cardiac chamber enlargement as a means to augment stroke volume, a condition known as the "athlete's heart." These changes have not been clearly characterized in female athletes. Multiple databases were searched from inception to June 18, 2019. Outcomes of interest included left ventricular (LV) and right ventricular (RV) dimensional, volumetric, mass, and functional assessments in female athletes. Most values were indexed to body surface area. The final search yielded 22 studies, including 1000 female athletes from endurance, strength, and mixed athletic disciplines. CMR-derived LV end-diastolic volume (LVEDV) and RV end-diastolic volume (RVEDV) were greater in endurance athletes (EA) versus HC (17.0% and 18.5%, respectively; both p < 0.001). Similarly, TTE-derived LVEDV and RVEDV were greater in EA versus HC (16.8% and 28.0%, respectively; both p < 0.001). Both LVEF and RVEF were lower in EA versus HC, with the most pronounced difference observed in RVEF via TTE (9%) (p < 0.001). LV stroke volume was greater in EA versus HC via both CMR (18.5%) and TTE (13.2%) (both p < 0.05). Few studies reported data for the mixed athlete (MA) population and even fewer studies reported data for strength athletes (SA), therefore a limited analysis was performed on MA and no analysis was performed on SA. This evidence-synthesis review demonstrates the RV may be more susceptible to ventricular enlargement. General changes in LV and RV structure and function in female EA mirrored changes observed in male counterparts. Further studies are needed to determine if potential adverse outcomes occur secondary to these changes.

Evidence of region-specific right ventricular functional adaptation in endurance-trained men in response to an acute volume infusion

NEW FINDINGS

What is the central question of this study? Endurance athletes demonstrate altered regional right ventricular (RV) wall mechanics, characterized by lower basal deformation, in comparison to non-athletic control subjects at rest. We hypothesized that regional adaptations at the RV base reflect an enhanced functional reserve capacity in response to haemodynamic volume loading. What is the main finding and its importance? Free wall RV longitudinal strain is elevated in response to acute volume loading in both endurance athletes and control subjects. However, the RV basal segment longitudinal strain response to acute volume infusion is greater in endurance athletes. Our findings suggest that training-induced cardiac remodelling might involve region-specific adaptation in the RV functional response to volume manipulation.

ABSTRACT

Eccentric remodelling of the right ventricle (RV) in response to increased blood volume and repetitive haemodynamic load during endurance exercise is well established. Structural remodelling is accompanied by decreased deformation at the base of the RV free wall, which might reflect an enhanced functional reserve capacity in response to haemodynamic perturbation. Therefore, in this study we examined the impact of acute blood volume expansion on RV wall mechanics in 16 young endurance-trained men (aged 24 ± 3 years) and 13 non-athletic male control subjects (aged 27 ± 5 years). Conventional echocardiographic parameters and the longitudinal strain and strain rate were quantified at the basal and apical levels of the RV free wall. Measurements were obtained at rest and after 7 ml/kg i.v. Gelofusine infusion, with and without a passive leg raise. After infusion, blood volume increased by 12 ± 4 and 14 ± 5% in endurance-trained individuals versus control subjects, respectively (P = 0.264). Both endurance-trained individuals (8 ± 10%) and control subjects (7 ± 9%) experienced an increase in free wall strain from baseline, which was also similar following leg raise (7 ± 10 and 6 ± 10%, respectively; P = 0.464). However, infusion evoked a greater increase in basal longitudinal strain in endurance-trained versus control subjects (16 ± 14 vs. 6 ± 11%; P = 0.048), which persisted after leg raise (16 ± 18 vs. 3 ± 11%; P = 0.032). Apical longitudinal strain and RV free wall strain rates were not different between groups and remained unchanged after infusion across all segments. Endurance training results in a greater contribution of longitudinal myocardial deformation at the base of the RV in response to a haemodynamic volume challenge, which might reflect a greater region-specific functional reserve capacity.

The Role of Multimodality Imaging in Athlete's Heart Diagnosis: Current Status and Future Directions

“Athlete’s heart” is a spectrum of morphological and functional changes which occur in the heart of people who practice physical activity. When athlete’s heart occurs with its most marked expression, it may overlap with a differential diagnosis with certain structural cardiac diseases, including cardiomyopathies, valvular diseases, aortopathies, myocarditis, and coronary artery anomalies. Identifying the underlying cardiac is essential to reduce the potential for sudden cardiac death. For this purpose, a spectrum of imaging modalities, including rest and exercise stress echocardiography, speckle tracking echocardiography, cardiac magnetic resonance, computed tomography, and nuclear scintigraphy, can be undertaken. The objective of this review article is to provide to the clinician a practical step-by-step approach, aiming at distinguishing between extreme physiology and structural cardiac disease during the athlete’s cardiovascular evaluation.

Ventricular arrhythmias in athletes: Role of a comprehensive diagnostic workup

BACKGROUND

Ventricular arrhythmias (VAs) represent a critical issue with regard to sports eligibility assessment in athletes. The ideal diagnostic evaluation of competitive and leisure-time athletes with complex VAs has not been clearly defined.

OBJECTIVE

The purpose of this study was to assess the clinical implications of invasive electrophysiological assessments and endomyocardial biopsy (EMB) among athletes with VAs.

METHODS

We evaluated 227 consecutive athletes who presented to our institutions after being disqualified from participating in sports because of VAs. After noninvasive tests, electrophysiological study (EPS), electroanatomic mapping (EAM), and EAM- or cardiac magnetic resonance imaging-guided EMB was performed, following a prespecified protocol. Sports eligibility status was redefined at 6-month follow-up.

RESULTS

From our sample, 188 athletes (82.8%) underwent EAM and EPS, and 42 (15.2%) underwent EMB. A diagnosis of heart disease could be formulated in 30% of the study population (67/227; 95% confidence interval [CI] 0.24-0.36) after noninvasive tests; in 37% (83/227; 95% CI 31%-43%) after EPS and EAM; and in 45% (102/227; 95% CI 39%-51%) after EMB. In the subset of athletes undergoing EMB, invasive diagnostic workup allowed diagnostic reclassification of half of the athletes (n = 21 [50%]). Reclassification was particularly common among subjects without definitive findings after noninvasive evaluation (n = 23; 87% reclassified). History of syncope, abnormal echocardiogram, presence of late gadolinium enhancement, and abnormal EAM were linked to sports ineligibility at 6-month follow-up.

CONCLUSION

A comprehensive invasive workup provided additional diagnostic elements and could improve the sports eligibility assessment of athletes presenting with VAs. The extensive invasive evaluation presented could be especially helpful when noninvasive tests show unclear findings.

A Novel Diagnostic Score Integrating Atrial Dimensions to Differentiate between the Athlete's Heart and Arrhythmogenic Right Ventricular Cardiomyopathy

Objective: The 2010 Task Force Criteria (TFC) have not been tested to differentiate ARVC from the athlete’s heart. Moreover, some criteria are not available (myocardial biopsy, genetic testing, morphology of ventricular tachycardia) or subject to interobserver variability (right ventricular regional wall motion abnormalities) in clinical practice. We hypothesized that atrial dimensions are useful and robust to differentiate between both entities and proposed a new diagnostic score based upon readily available parameters including echocardiographic atrial dimensions. Methods: In this observational study, 21 patients with definite ARVC were matched for age, gender and body mass index to 42 athletes. Based on ROC analysis, the following parameters were included in the score: indexed right/left atrial volumes ratio (RAVI/LAVI ratio), NT-proBNP, RVOT measurements (PLAX and PSAX BSA-corrected), tricuspid annular motion (TAM), precordial TWI and depolarization abnormalities according to TFC. Results: ARVC patients had a higher RAVI/LAVI ratio (1.76 ± 1.5 vs. 0.87 ± 0.2, p < 0.001), lower right ventricular function (fac: 29 ± 10.1 vs. 42.2 ± 5%, p < 0.001; TAM: 19.8 ± 5.4 vs. 23.8 ± 3.8 mm, p = 0.001) and higher serum NT-proBNP levels (345 ± 612 vs. 48 ± 57 ng/L, p < 0.001). Our score showed a good performance, which is comparable to the 2010 TFC using those parameters, which are available in routine clinical practice (AUC93%, p < 0.001 (95%CI 0.874–0.995) vs. AUC97%, p < 0.001 (95%CI 0.93–1.00). A score of 6/12 points yielded a specificity of 91% and an improved sensitivity of 67% for ARVC diagnosis as compared to a sensitivity of 41% for the abovementioned readily available 2010 TFC. Conclusions: ARVC patients present with significantly larger RA compared to athletes, resulting in a greater RAVI/LAVI ratio. Our novel diagnostic score includes readily available clinical parameters and has a high diagnostic accuracy to differentiate between ARVC and the athlete’s heart.

Exercise Training Induces Left- but not Right-sided Cardiac Remodelling in Olympic Rowers

Whilst the athlete's heart has been extensively described, less work has focused on the potential for elite athletes to demonstrate further cardiac remodelling upon an increase in training volume. Moreover, little work explored potential side-specific cardiac remodelling. Therefore, we examined the impact of an increase in training volume across 9-months in elite rowers on left- and right-sided cardiac structure, function and mechanics (i. e. longitudinal, radial and circumferential strain, twist and strain-volume loops). As part of the preparations to the 2012 Olympic Games, twenty-seven elite rowers (26.4±3.7years, 19 male) underwent echocardiography prior to and post (9 months) an increase in training volume (24 to 30-35 h weekly). Training increased left ventricular structure, including wall thickness, diameter, volume, mass and LV twist (all p<0.05). Female rowers demonstrated larger adaptation in left ventricular diameter and mass compared to male rowers (both p<0.05). No changes were observed in other measures of left ventricular function in both sexes (all p>0.05). The 9-month intervention showed no change in right ventricular/atrial structure, function or mechanics (all p>0.05). In conclusion, our data revealed that 9-month increased training volume in elite rowers induced left-sided (but not right-sided) structural remodelling, concomitant with an increase in left ventricular twist, with some changes larger in women.

Anatomical-MRI Correlations in Adults and Children with Arrhythmogenic Right Ventricular Cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare disease in which the right ventricular myocardium is replaced by islands of fibro-adipose tissue. Therefore, ventricular re-entry circuits can occur, predisposing the patient to ventricular tachyarrhythmias, as well as dilation of the right ventricle that eventually leads to heart failure. Although it is a rare disease with low prevalence in Europe and the United States, many patients are addressed disproportionately for cardiac magnetic resonance imaging (MRI). The most severe consequence of this condition is sudden cardiac death at a young age due to untreated cardiac arrhythmias. The purpose of this paper is to revise the magnetic resonance characteristics of ARVC, including the segmental contraction abnormalities, fatty tissue replacement, decrease of the ejection fraction, and the global RV dilation. Herein, we also present several recent improvements of the 2010 Task Force criteria that are not included within the ARVC diagnosis guidelines. In our opinion, these features will be considered in a future Task Force Consensus.

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

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

Arrhythmogenic right ventricular cardiomyopathy and sports activity: from molecular pathways in diseased hearts to new insights into the athletic heart mimicry

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inherited disease associated with a high risk of sudden cardiac death. Among other factors, physical exercise has been clearly identified as a strong determinant of phenotypic expression of the disease, arrhythmia risk, and disease progression. Because of this, current guidelines advise that individuals with ARVC should not participate in competitive or frequent high-intensity endurance exercise. Exercise-induced electrical and morphological para-physiological remodelling (the so-called 'athlete's heart') may mimic several of the classic features of ARVC. Therefore, the current International Task Force Criteria for disease diagnosis may not perform as well in athletes. Clear adjudication between the two conditions is often a real challenge, with false positives, that may lead to unnecessary treatments, and false negatives, which may leave patients unprotected, both of which are equally inacceptable. This review aims to summarize the molecular interactions caused by physical activity in inducing cardiac structural alterations, and the impact of sports on arrhythmia occurrence and other clinical consequences in patients with ARVC, and help the physicians in setting the two conditions apart.

Right Ventricular Function and Region-Specific Adaptation in Athletes Engaged in High-Dynamic Sports: A Meta-Analysis

BACKGROUND

Structural remodeling of the right ventricle (RV) is widely documented in athletes. However, functional adaptation, including RV pressure generation and systolic free-wall longitudinal mechanics, remains equivocal. This meta-analysis compared RV pressure and function in athletes and controls.

METHODS

A systematic review of online databases was conducted up to June 4, 2020. Meta-analyses were performed on RV systolic pressures, at rest and during exercise, tricuspid annular plane systolic displacement, myocardial velocity (S'), and global and regional longitudinal strain. Bias was assessed using Egger regression for asymmetry. Data were analyzed using random-effects models with weighted mean difference and 95% CI.

RESULTS

Fifty-three studies were eligible for inclusion. RV systolic pressure was obtained from 21 studies at rest (n=1043:1651; controls:athletes) and 8 studies during exercise (n=240:495) and was significantly greater in athletes at rest (weighted mean difference, 2.9 mmHg [CI, 1.3-4.5 mmHg]; P=0.0005) and during exercise (11.0 [6.5-15.6 mm Hg]; P<0.0001) versus controls. Resting tricuspid annular plane systolic displacement (P<0.0001) and S' (P=0.001) were greater in athletes. In contrast, athletes had similar RV free-wall longitudinal strain (17 studies; n=450:605), compared with controls but showed greater longitudinal apical strain (16 studies; n=455:669; 0.9%, 0.1%-1.8%; P=0.03) and lower basal strain (-2.5% [-1.4 to -3.5%]; P<0.0001).

CONCLUSIONS

Functional RV adaptation, characterized by increased tricuspid annular displacement and velocity and a greater base-to-apex strain gradient, is a normal feature of the athlete's heart, together with a slightly elevated RV systolic pressure. These findings contribute to our understanding of RV in athletes and highlight the importance of considering RV function in combination with structure in the clinical interpretation of the athlete's heart.

Role of Exercise as a Modulating Factor in Arrhythmogenic Cardiomyopathy

PURPOSE OF REVIEW

The review addresses the role of exercise in triggering ventricular arrhythmias and promoting disease progression in arrhythmogenic cardiomyopathy (AC) patients and gene-mutation carriers, the differential diagnosis between AC and athlete's heart and current recommendations on exercise activity in AC.

RECENT FINDINGS

AC is an inherited heart muscle disease caused by genetically defective cell-to-cell adhesion structures (mainly desmosomes). The pathophysiological hallmark of the disease is progressive myocyte loss and replacement by fibro-fatty tissue, which creates the substrates for ventricular arrhythmias. Animal and human studies demonstrated that intense exercise, but not moderate physical activity, may increase disease penetrance, worsen the phenotype, and favor life-threatening ventricular arrhythmias. It has been proposed that in some individuals prolonged endurance sports activity may in itself cause AC (so-called exercise-induced AC). The studies agree that intense physical activity should be avoided in patients with AC and healthy gene-mutation carriers. However, low-to-moderate intensity exercise does not appear detrimental and these patients should not be entirely deprived from the many health benefits of physical activity.

Left Ventricular Fibrosis in Middle-Age Athletes and Physically Active Adults

INTRODUCTION

Cardiac magnetic resonance (CMR) late gadolinium enhancement (LGE) and T1 mapping techniques enable the quantification of focal and diffuse myocardial LGE, respectively. Studies have shown evidence of fibrosis in middle-age athletes, but not relative to physically active (PA) adults who perform recommended physical activity levels. Therefore, we examined cardiac remodeling and presence of left ventricular (LV) LGE and T1 values in both recreational middle-age endurance athletes (EA) and PA adults.

METHODS

Healthy EA and PA adults (45-65 yr) completed a standardized 3-T CMR protocol with ventricular volumetry, LV LGE, and T1 mapping.

RESULTS

Seventy-two EA and 20 PA participants (mean age, 53 ± 5 vs 56 ± 4 yr; P < 0.01; V˙O2peak = 50 ± 7 vs 37 ± 9 mL·kg·min, P < 0.0001) were examined, with CMR data available in 89/92 participants. Focal LV LGE was observed in 30% of participants (n = 27/89): 33% of EA (n = 23/69; 33%) and 20% of PA (n = 4/20; 20%). LGE was present at the right ventricular hinge point (n = 21/89; 23.5%) or identified as ischemic (n = 2/89; 2%) or nonischemic (n = 4/89; 4%). Focal LV LGE was observed similarly in both EA and PA (P = 0.25). EA had larger LV chamber sizes and T1 native values (1169 ± 35 vs 1190 ± 26, P = 0.02) compared with PA, with similar LV ejection fraction. Global extracellular volume (ECV) was similar in both EA and PA (22.6% ± 3.5% vs 21.5% ± 2.6%, P = 0.26), with no relationship between global ECV and LV mass (r = -0.16, P = 0.19).

CONCLUSIONS

Focal LGE at the right ventricular hinge point was detected at the same frequency in both groups, was unrelated to demographic or clinical indices, and was found without evidence of global ECV expansion in EA, suggesting a physiologic remodeling response. The long-term clinical implications of hinge-point LGE require clarification using prospective, long-term follow-up studies.

Analysis of left ventricular rotational deformation by 2D speckle tracking echocardiography: a feasibility study in athletes

2D speckle tracking echocardiography (2DSTE) is established to analyse left ventricular (LV) longitudinal function. The analysis of LV rotational deformation is challenging and requires standardization of image acquisition as well as postprocessing analysis. The aim of this study was to test the feasibility to analyse LV rotational deformation using 2DSTE by introducing a novel algorithm for the detection of artefacts. The study was performed in 20 healthy subjects serving as a control group and in 53 competitive sportsmen. Circumferential, radial strain (CS, RS) and LV rotation were analysed by 2DSTE in parasternal short axis views. The stepwise algorithm to exclude potential artefacts starts with the visual estimation of the image quality with respect to complete visualization of all myocardial segments during the entire cardiac cycle followed by the exclusion of data sets in participants with conduction abnormalities. The next step is the optimization of tracking areas and a cross-check of implausible strain waveforms in multiple acquired comparable cineloops. The last step is the exclusion of strain curves with persisting implausible waveforms if standardization failures and incorrect LV wall tracking are fixed. Plausible physiological strain curves were observed in 89% (n = 65/73) of all subjects. In controls all implausible waveforms could be verified as artefacts. The algorithm was applied in 53 professional athletes to test and confirm its feasibility. Abnormal CS waveforms were documented in 25 athletes, verified as artefacts due to tracking failures in 22 athletes and due to incorrect image acquisition in 3 athletes. CS artefacts were mostly located in the basal posterior and lateral LV segments. (endocardial: 6%, n = 4/70; p < 0.05) and basal posterior (endocardial: 8%, n = 5/70; p < 0.05) segments were highly susceptible to artefacts. 2DSTE of parasternal short axis views to analyse circumferential and radial deformation as well as LV rotation is feasible in athletes. The proposed algorithm helps to avoid artefacts and might contribute to standardization of this technique. 2DSTE might provide an interesting diagnostic tool for the detection of viral myocarditis, e.g. in athletes.

The acute effects of an ultramarathon on biventricular function and ventricular arrhythmias in master athletes

AIMS

Endurance sports practice has significantly increased over the last decades, with a growing proportion of participants older than 40 years. Although the benefits of moderate regular exercise are well known, concerns exist regarding the potential negative effects induced by extreme endurance sport. The aim of this study was to analyse the acute effects of an ultramarathon race on the electrocardiogram (ECG), biventricular function, and ventricular arrhythmias in a population of master athletes.

METHODS AND RESULTS

Master athletes participating in an ultramarathon (50 km, 600 m of elevation gain) with no history of heart disease were recruited. A single-lead ECG was recorded continuously from the day before to the end of the race. Echocardiography and 12-lead resting ECG were performed before and at the end of the race. The study sample consisted of 68 healthy non-professional master athletes. Compared with baseline, R-wave amplitude in V1 and QTc duration were higher after the race (P < 0.001). Exercise-induced isolated premature ventricular beats were observed in 7% of athletes; none showed non-sustained ventricular tachycardia before or during the race. Left ventricular ejection fraction, global longitudinal strain (GLS), and twisting did not significantly differ before and after the race. After the race, no significant differences were found in right ventricular inflow and outflow tract dimensions, fractional area change, s', and free wall GLS.

CONCLUSION 

In master endurance athletes running an ultra-marathon, exercise-induced ventricular dysfunction, or relevant ventricular arrhythmias was not detected. These results did not confirm the hypothesis of a detrimental acute effect of strenuous exercise on the heart.

Gender Difference of Cardiac Remodeling in University Athletes: Results from 2015 Gwangju Summer Universiade

Background and Objectives

There is little data about cardiac geometry in highly trained young athletes, especially female specific changes. We investigated gender difference on exercise induced cardiac remodeling (EICR) in highly trained university athletes.

Methods

A total of 1,185 university athletes divided into 2 groups; female (n=497, 22.0±2.3 years) vs. male (n=688, 22.6±2.4 years). Remodeling of the left ventricle (LV), left atrium (LA), right ventricle (RV), and any cardiac chamber were compared.

Results

LV, LA, RV, and any remodeling was found in 156 (13.2%), 206 (17.4%), 82 (6.9%), and 379 athletes (31.9%), respectively. LV, LA, and any remodeling were more common in male than female athletes (n=53, 12.1% vs. n=103, 15.5%, p=0.065), (n=65, 13.1% vs. n=141, 20.5%, p<0.001), (n=144, 30.0% vs. n=235, 34.2%, p=0.058), respectively, whereas RV remodeling was significantly more common in female than male athletes (n=56, 11.3% vs. n=26, 3.8%, p<0.001). Interestingly, the development of LV, LA, and RV remodeling were not overlapped in many of athletes, suggesting different mechanism of EICR according to cardiac chamber. Various predictors including sports type, heart rate, muscle mass, fat mass, body surface area, and training time were differently involved in cardiac remodeling, and there were gender differences of these predictors for cardiac remodeling.

Conclusions

EICR was common in both sex and was independently developed among cardiac chambers in highly trained university athletes. LV and LA remodeling were common in males, whereas RV remodeling was significantly more common in females demonstrating gender difference in EICR. The present study also demonstrated gender difference in the predictors of EICR.

The Female Athlete's Heart: Overview and Management of Cardiovascular Diseases

The number of female athletes taking part in elite and amateur sport is ever increasing. In contrast with male athletes, few studies have focused on cardiovascular adaptations to exercise in women, the effects of lifelong exercise on heart muscle and electrical tissue, the risk of exerciserelated sudden cardiac death and the management of cardiovascular disease. Women have a lower prevalence of large QRS complexes, repolarisation changes including inferior and lateral T-wave inversion, and cardiac dimensions exceeding predicted limits compared with men. The risk of exercise-related sudden cardiac death is significantly lower in women than men. Also, women who have engaged in lifelong exercise do not have a higher prevalence of AF, coronary artery calcification or myocardial fibrosis than their sedentary counterparts. Apart from providing an overview of the existing literature relating to cardiac adaptations, this review explores possible reasons for the sex differences and focuses on the management of cardiovascular disorders that affect female athletes.

Echocardiographic Characterization of Female Professional Basketball Players in the US

Importance

There is a paucity of data detailing cardiac remodeling in female athletes compared with male athletes. The lack of reference cardiac data for elite female basketball players or female athletes of similar size makes it difficult to differentiate athletic remodeling from potential underlying cardiac disorders in this population of athletes.

Objective

To assess cardiac structure and function in elite female basketball players.

Design, Setting, and Participants

This cross-sectional echocardiographic study included 140 Women's National Basketball Association (WNBA) athletes on active rosters for the 2017 season. The WNBA mandates annual preseason stress echocardiograms for each athlete. The WNBA has partnered with Columbia University to annually perform a review of these studies. Data analysis was performed from June 7, 2017, to October 5, 2017.

Main Outcomes and Measures

Echocardiographic variables included left ventricular (LV) dimensions, wall thickness, mass, prevalence of LV hypertrophy, aortic dimensions, right ventricular (RV) dimension, and right and left atrial size. Linear regression was used to assess the associations between cardiac structure and function with body size quantified as body surface area (BSA) in the primary analysis.

Results

A total of 140 female athletes (mean [SD] age, 26.8 [3.9] years; 105 [75.0%] African American) participated in the study. Mean (SD) athlete height was 183.4 (9.0) cm, and mean (SD) BSA was 2.02 (0.18) m2. Compared with guideline-defined normal values, LV enlargement was present in 36 athletes (26.0%) and 57 athletes (42.2%) had RV enlargement. There was a linear correlation between LV and RV cavity sizes and BSA extending to the uppermost biometrics (LV cavity size: r, 0.48; RV cavity size: r, 0.32; P < .001 for both). Maximal left ventricular wall thickness (LVWT) ranged from 0.6 to 1.4 cm, with 78 athletes (55.7%) having LVWT of 1.0 cm or greater and only 1 athlete (0.7%) having LVWT greater than 1.3 cm. Twenty-three athletes (16.4%) met the criteria for left ventricular hypertrophy (LVH) (>95 g/m2). Eccentric LVH was present in 16 athletes (69.6%), concentric LVH in 7 athletes (30.4%), and concentric remodeling in 27 athletes (19.3%). Mean aortic root diameter was 3.1 cm (95% CI, 3.0-3.2). Only 2 athletes (1.4%) had guideline-defined aortic enlargement compared with a range of 18% to 42% for left and right ventricular and atrial enlargement.

Conclusions and Relevance

In this study, increased cardiac dimensions were frequently observed in WNBA athletes. Both BSA and physiologic remodeling affected cardiac morphologic findings. This study may provide a framework to define the range of athletic cardiac remodeling exhibited by elite female basketball players.

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

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

Diagnostic electrophysiological study in a highly trained young woman with presyncopal symptoms during exercise: a case report

Right ventricular outflow tract (RVOT) ventricular tachycardia (VT) is frequent and occurs in patients without structural heart disease, especially in highly trained athletes. Most of the studies on cardiac adaptations to exercise have been investigated in male athletes. Women, however, are increasingly participating in sports and electrical and structural adaptations in male and female athletes differ significantly. These cardiac adaptations dissimilarities between males and females have potential implications in diagnosing certain types of arrhythmias. We present here a case of a 35-year-old highly-trained woman endurance athlete that attended the clinic complaining about chest pain and dyspnea on exertion, dizziness and presyncope occurring during maximum-intensity exercise training sessions. An exercise stress testing was performed on cycle ergometer. The test elapsed normally until the patient reached a heart rate of 169 bpm, when she presented identical symptoms to those described during the first interview in the clinic. A wide-complex and notched QRS tachycardia was observed in the inferior leads, inferior axis leads and transition from leads V4 to V5, suspending the test immediately. The patient was referred to perform an electrophysiological study and eventually radiofrequency catheter ablation in order to eliminate the culprit VT. Precocity occurred in the posterior lateral wall of the RVOT, immediately below the pulmonary valve. Radiofrequency application in the arrhythmogenic focus suppressed all ectopic activity despite maintaining isoproterenol infusion. After 30 minutes, the effect was maintained, and the ectopic focus was successfully ablated. The recognition of this clinical entity in females may be challenging since cardiac remodeling in response to exercise may be invaluable due to their biological, anatomical, and hormonal characteristics. In effect, electrical and structural adaptations in males and females may differ considerably. Both exercise stress testing and diagnostic electrophysiological study represent essential and invaluable tools to reach a final diagnosis, especially in highly trained females.

Female Athlete's Heart: Sex Effects on Electrical and Structural Remodeling

BACKGROUND

Most of our knowledge on training-induced cardiac remodeling is derived from men, with the paucity of data from women representing an important gap in knowledge. The aim of the study was to define the electrocardiographic and morphological features of female athlete's heart, with special attention to differences related to sex and sport.

METHODS

Seven hundred twenty Olympic athletes (360 females and 360 age- and sport-matched males, mean age: 23±5 years) were evaluated by clinical, resting, and exercise electrocardiography and echocardiography.

RESULTS

Anterior T-wave inversion was more common in females than males (P<0.05). Left ventricular (LV) wall thickness and LV mass were greater in men (P<0.001). Females had smaller absolute but greater indexed LV and right ventricular (RV) dimensions as compared to males. Most women had normal LV geometry (80.8%). A progressive increase in LV/RV dimensions was observed in women from those engaged in skill, power, to mixed and endurance disciplines, with the endurance ones demonstrating the greatest degree of RV dilatation. Women had a peculiar biventricular adaptation, with higher LV/RV (1.41±0.16 versus 1.36±0.15, P<0.0001) and lower RV inflow/outflow ratio (P<0.001), as compared to men.

CONCLUSIONS

Sex significantly affects cardiac remodeling in athletes, with females presenting a different electrical and structural remodeling. Women maintain a normal LV geometry, with relative larger increase of cavity dimensions compared with men. Type of sport has a relevant impact, with endurance athletes exhibiting the greatest degree of RV and LV dimensional remodeling. The present study confirms the need for a sex-based approach for interpreting the complex features of athlete's heart in women.

Role of echocardiography in screening and evaluation of athletes

The term athlete's heart describes structural, functional and electrical adaptations of the cardiovascular system due to repetitive intense exercise. Physiological cardiac adaptations in athletes, however, may mimic features of cardiac diseases and therefore make it difficult to distinguish physiological adaptions from disease. Furthermore, regular exercise may also lead to pathological adaptions that can promote or worsen cardiac disease (eg, atrial dilation/atrial fibrillation, aortic dilation/aortic dissection and rhythm disorders). Sudden cardiac death (SCD) is a major concern in sports cardiology, and preparticipation screening (PPS) has demonstrated to be effective in identifying athletes at risk for SCD. In Europe, PPS is advocated to include personal and family history, physical examination and ECG, with further workup including echocardiography only if the initial screening investigations show abnormal findings. We review the current available evidence for echocardiography as a screening tool for conditions associated with SCD in recreational and professional athletes and advocate to include screening echocardiography to be performed at least twice in an athlete's career. We recommend that the first echocardiography is performed during adolescence to rule out structural heart conditions associated with SCD that cannot be detected by ECG, especially mitral valve prolapse, coronary artery anomalies, bicuspid aortic valve and dilatation of the aorta. A second echocardiography could be performed from the age of 30-35 years, when athletes age and become master athletes, to especially evaluate pathological cardiac remodelling to exercise (eg, atrial and/or right ventricular dilation), late onset cardiomyopathies and wall motion abnormalities due to myocarditis or coronary artery disease.

Analysis of Regional Right Ventricular Function by Tissue Doppler Imaging and Three-Dimensional Echocardiography in Highly Trained Athletes

Background:

Regional right ventricular (RV) function has not yet been characterized in highly trained athletes, and the effects of increased RV volumes on resting changes of regional RV deformation are unknown.

Purpose:

The aim of the study was to analyze global and regional RV function by a multisegmental approach using tissue Doppler imaging (TDI) and to determine whether higher RV volumes evaluated by three-dimensional echocardiography (3DE) had an impact on the RV mechanics assessed by resting regional TDI parameters.

Methods:

We enrolled prospectively 25 professional soccer players and 25 age- and sex-matched nonathletic controls. Transthoracic echocardiography including additional views of the RV was performed. The TDI sample volume was placed in the basal region of the anterior, inferior, and RV free wall to assess the following parameters: isovolumic contraction time (IVCT_RV), isovolumic relaxation time (IVRT_RV), ejection time (ET_RV), and myocardial performance index (MPI_RV). Furthermore, conventional left ventricular (LV) and RV parameters at two-dimensional (2D) and 3DE were determined.

Results:

In athletes, LV mass index/body surface area (BSA), left atrial volume index, 2D LV volumes/BSA were significantly increased in comparison with controls. Moreover, athletes had higher 2D LV and RV stroke volume (SV), lower values for A wave and E/e' ratio, higher basal RV diameter, and right atrial (RA) area (P < 0.0001). Moreover, athletes showed significantly increased LV and RV volumes and SV indexed for BSA (P < 0.0001) evaluated at 3DE. In athletes, ET_{RV-free wall}, ET_RV-anterior, IVCT_RV-inferior, and IVCT_RV-anterior were statistically increased (P < 0.0001). Conversely, IVRT_RV-anterior was reduced in comparison with controls. A significant positive correlation between IVRT_RV-inferior and three-dimensional (3D) RV end-diastolic volume (EDV), end-systolic volume, and SV was observed in athletes. Finally, a good positive correlation was observed between 3D RV EDV and 3D LV SV indexed for BSA.

Conclusions:

In athletes, the higher 3D RV volumes are proportionally related to an increase of IVRT_RV-inferior and 3D LV SV. Further studies on the resting changes of regional RV deformation for screening and follow-up in these participants are needed.