Early Repolarization in Athletes

Digitized Electrocardiography Measurements Support the Biological Plausibility of the Pathological Significance of ST Segments in Athletes

OBJECTIVE

ST segment deviations around the isoelectric line are common findings in manifest cardiovascular disease. In athletes, ST elevation is common, while ST depression is considered rare. However, clinical studies in athletes have associated ST depression with myocardial fibrosis and fatty infiltration and ST elevation with pericarditis and myocarditis. This study aims to explore the association between resting ST segment deviations and resting heart rate, an indicator of training and autonomic tone and electrocardiography (ECG) markers of exercise training effect and cardiovascular health R and T wave amplitude.

DESIGN

Retrospective analysis of digitized ECG data.

SETTING

Institutional setting.

PARTICIPANTS

Seven thousand eight hundred thirty-six (male athletes = 4592, female athletes = 3244) healthy asymptomatic athletes (14-35 years).

MAIN OUTCOME MEASURES

A series of correlations and regressions were conducted between ST depression (<0.0 µV) and ST elevation (>0.0 µV), on R and T wave amplitudes, and heart rate in leads V2, V5, and aVF.

RESULTS

Positive correlations between ST elevation and R and T wave (S wave in V2) amplitudes and leads V5, V2, and aVF in male and female athletes (range of r = 0.1-0.54). In addition, there was a negative correlation between ST elevation and HR for male and female athletes. Finally, there was a negative correlation between ST depression and R wave and HR for male and female athletes in V5 ( P < 0.01).

CONCLUSIONS

In athletes, ST segment elevation is correlated with R and T wave amplitudes and negatively correlated with HR. In addition, ST segment elevation is correlated with low heart rate, consistent with its higher prevalence in athletes. ST segment depression is not influenced by HR but is negatively associated with R and T wave amplitudes.

Increased Prevalence of the Electrocardiographic Early Repolarization Pattern in Young Patients With Vagally Mediated Syncope: A Case-Control Study

Background

Electrocardiographic early repolarization (EER) is linked with idiopathic ventricular fibrillation in adults. It is frequently seen in children, with poorly understood significance. Some evidence suggests that it could be a vagally mediated phenomenon. A retrospective case-control study was undertaken to test the hypothesis that EER is more common among children with typical vasovagal syncope (VVS) than among their peers with nonvagal syncope (NVS) or with no syncope.

Methods

Patients aged 4-18 years with syncope were identified by a single-centre database search followed by a review of history for features of VVS (n = 150) or NVS (n = 84). The first available electrocardiogram (ECG) for VVS or for NVS was retrieved. Age- and sex-matched children with no known syncope or heart disease were then identified (n = 216). ECGs were assessed separately for EER based on published criteria by 2 observers blinded to patients' clinical status.

Results

Mean age was 12.3 ± 3.2 years, and heart rate was 74.2 ± 16.5 beats/min. EER was more prevalent in VVS (33.3%) than among patients with NVS (19.1%; odds ratio: 2.29; confidence interval: 1.32-5.50) or among those with no syncope (12.5%; odds ratio: 3.14; confidence interval: 1.81-5.46). Heart rates were significantly lower in VVS and NVS (heart rate: 70.1 ± 13.8 and 70.7 ± 12.4 beats/min, respectively) compared with children with no syncope (heart rate: 78.2 ± 18.0 beats/min), both P < 0.001.

Conclusions

EER is more common in paediatric patients with VVS than those with NVS or without syncope, consistent with a possible vagal contribution to the ECG finding.

Early repolarization in adolescent athletes: A gender comparison of ECG and echocardiographic characteristics

BACKGROUND

The early repolarization pattern (ERp) is an electrocardiographic finding previously associated with arrhythmic risk in adults. The purpose of this study is to evaluate the prevalence and characteristics of ERp in a group of adolescent athletes according to gender. Furthermore, potential associations with clinical, electrocardiographic, and echocardiographic parameters are explored.

METHODS

In this cross-sectional study young athletes (age < 18 years) were consecutively enrolled during the annual pre-participation evaluation, undergoing also transthoracic echocardiography assessment from January 2015 to March 2020.

RESULTS

The prevalence of ERp was 27% in the whole population. Athletes with ERp were more frequently men practicing endurance sports. Women with ERp showed lower heart rate at rest, greater posterior, and relative ventricular wall thickness than those without ERp. Men with ERp presented higher systolic blood pressure at peak exercise, greater septal wall thickness, and indexed left ventricular mass than those without ERp. Both genders with ERp showed increased QRS voltage and narrower QRS duration. The ERp phenotype in men was more frequently notched with higher amplitude and ascending ST segment. Women's ERp presented more frequently a slurred morphology, especially in the inferior leads, and horizontal ST slope. No differences emerged in the occurrence of arrhythmias at rest and during maximal exercise test between groups, even considering higher risk phenotypes.

CONCLUSIONS

ERp is an ECG finding compatible with normal cardiac adaptations to training in young athletes. ERp demonstrated gender differences regarding phenotypes previously associated with increased cardiovascular risk, not showing any differences in arrhythmias during maximal exercise test.

Association Between Temporal Changes in Early Repolarization Pattern With Long-Term Cardiovascular Outcome: A Population-Based Cohort Study

Background

The prognostic value of early repolarization pattern (ERP) remains controversial. We aim to test the hypothesis that temporal changes in ERP are associated with increased risks for sudden cardiac death (SCD) and cardiovascular death.

Methods and Results

A total of 14 679 middle‐aged participants from the prospective, population‐based cohort were included in this analysis, with ERP status recorded at baseline and during 3 follow‐up visits in the ARIC (Atherosclerosis Risk in Communities) study. We related baseline ERP, time‐varying ERP, and temporal changes in ERP to cardiovascular outcomes. Cox models were used to estimate the hazard ratios (HRs) adjusted for possible confounding factors. With a median follow‐up of 22.5 years, there were 5033 deaths, 1239 cardiovascular deaths, and 571 SCDs. Time‐varying ERP was associated with increased risks of SCD (HR, 1.59 [95% CI, 1.25–2.02]), cardiovascular death (HR, 1.70 [95% CI, 1.44–2.00]), and death from any cause (HR, 1.16 [95% CI, 1.05–1.27]). Baseline ERP was also associated with 3 outcomes. Compared with those with consistently normal ECG findings, subjects with new‐onset ERP or consistent ERP experienced increased risks of developing SCD and cardiovascular death. The time‐varying ERP in women, White subjects, and anterior leads and J‐wave amplitudes ≥0.2 mV appeared to indicate poorer cardiovascular outcomes.

Conclusions

Our findings suggest that baseline ERP, time‐varying ERP, new‐onset ERP, and consistent ERP were independent predictors of SCD and cardiovascular death in the middle‐aged biracial population. Repeated measurements of the ERP might improve its use as a risk indicator for SCD.

Electrical and Structural Adaption of Athlete’s Heart and the Impact on Training and Recovery Management in Professional Basketball Players: A Retrospective Observational Study

Introduction

We analyzed data of 27 professional basketball players to prove cardiac remodeling referring echocardiographic parameters, cardiopulmonary exercise testing (CPET), and 12-lead electrocardiogram (ECG) analyses. The aim of our study was to present different characteristics in the athletes, on the one hand signs of a high vagal tone in the 12-lead ECG as criteria of early repolarization (ER), furthermore echocardiographic remodeling parameters and finally the performance in CPET. Therefore, we divided the cohort into a group with signs of ER pattern in the 12-lead ECG and without these criteria and presented the differences in detail.

Materials and Methods

This was a single-center, retrospective study performed in 27 professional basketball players (age: 26.5 ± 7.5 years, male: 27, height: 197.2 ± 12 cm, weight: 100 ± 17 kg, BMI: 25.7 ± 3.4 kg/m2). All participants underwent a sports medicine checkup, ECG analysis, transthoracic echocardiographic examination, and a CPET on a cycle ergometer between 2015 and 2019 during their pre-season preparation time. All individuals were healthy people without cardiological advance anamnesis. After assessment, two groups were built based on electrocardiographic criteria of ER pattern and a group without these criteria and compared against each other for parameters of echocardiographic assessment, CPET, and 12-lead ECG analysis. Data were analyzed with Minitab statistic program (Minitab Inc., State College, PA, United States) and Graph Pad Prism 8.2.1 (279; Graph Pad Software, San Diego, CA, United States) using ANOVA testing with post-hoc testing and unpaired t-testing (p ≤ 0.05).

Retrospectively additional information was collected referring to the management of training sessions, recovery time, and nutrition by interviewing the athletic training staff in order to understand the principles for individual athlete’s training management and physiological and cardiopulmonary interactions.

Results

Comparing professional basketball players with ER pattern to those with no ER pattern, significant differences were found for CPET, echocardiographic, and ECG analysis (p &lt; 0.05). Absolute and relativized peak oxygen uptake (VO2 peak; ER 4120 ± 750 ml/min (39 ± 5.4 ml/kg/min) vs. non-ER 3556 ± 393 ml/min (37.2 ± 5.3 ml/kg/min), p = 0.018) and maximum workload during CPET (ER 310 ± 51.5 Watt (2.94 ± 0.35 W/kg) vs. non-ER 271 ± 32 Watt (2.85 ± 0.49 W/kg), p = 0.026) was higher in athletes with an ER pattern. Furthermore, ER pattern athletes showed a higher enddiastolic left ventricular diameter (LVedd; ER 58.3 ± 7.9 mm vs. non-ER 53.6 ± 3.6 mm, p = 0.048) and a significantly enlarged left atrial (LA) endsystolic diameter (ER 23.33 ± 2.71 mm vs. non-ER 20.47 ± 2.29 mm, p = 0.006) as well as a significantly enlarged right atrial (RA) endsystolic diameter (ER 23.42 ± 2.15 mm vs. non-ER 20.93 ± 3.28 mm, p = 0.033). Significant differences between the two compared groups could be revealed for left ventricular mass Index (LVMI gr/m2; LVMI ER 113 gr/m2 ± 17.5 vs. LVMI non-ER 91.3 gr/m2 ± 15.1, p = 0.002), but no significant differences for the relative wall thickness were found (RWT; RWT ER 0.49 ± 0.11 vs. RWT non-ER 0.38 ± 0.06, p = 0.614).

Conclusion

Professional basketball players with criteria of ER pattern showed different results in CPET and cardiac remodeling as athletes with no ER pattern. These findings should encourage the athletic training staff to emphasize the quality of an individual training schedule for each athlete based on the cardiopulmonary pre-season sport medicine checkup. Nevertheless, echocardiographic findings, ER pattern, and performance in CPET have to be interpreted referring the sport-specific and athlete’s ethnical background.

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.

Early Repolarization in Pediatric Athletes: A Dynamic Electrocardiographic Pattern With Benign Prognosis

Background

Early repolarization pattern (ERP) is considered a common training‐related and benign ECG finding in young adult athletes. Few data exist on ERP in the pediatric athletes population. Therefore, we aimed to evaluate the ERP prevalence, characteristics, and prognosis in pediatric athletes aged ≤16 years.

Methods and Results

Eight‐hundred eighty‐six consecutive pediatric athletes engaged in 17 different sports (mean age, 11.7±2.5 years; 7–16 years) were enrolled and prospectively evaluated with medical history, physical examination, resting and exercise ECGs, and transthoracic echocardiography during their preparticipation screening. Known cardiovascular diseases associated with sudden cardiac death was considered exclusion criteria. Athletes were followed up yearly for 4 years. The prevalence of ERP was 117 (13.2%), equally distributed in both sexes (P=0.072), irrespectively of body mass index and classification of sports. The most common ERP localizations were inferolateral and inferior leads (53.8% and 27.3%, respectively). Notching J‐point morphology was the most prevalent (70%), and rapidly ascending ST elevation (96%) was the most common ST‐segment morphology. Athletes with ERP were older (P<0.001) had lower rest and recovery heart rates (P<0.001), increased precordial and limb R‐wave voltages (P<0.001), increased R/S Sokolow index (P<0.001), and longer PR interval (P=0.006) in comparison with the athletes without ERP. Neither major cardiovascular nor arrhythmic events, nor sudden cardiac death were recorded over a median follow‐up of 4.2 years. One hundred seventeen (80.3%) athletes with ERP exhibited a persistent ERP. ERP localization and J‐point morphology changed during follow‐up in 11 (11.7%) and 17 (18%) of athletes, respectively.

Conclusions

ERP is common in pediatric athletes. It was mostly located in the inferolateral leads and associated with concave ascending ST segment with other training‐related ECG changes. The lack of either sudden cardiac death or cardiomyopathies linked to sudden cardiac death over follow‐up suggests that in pediatric athletes, ERP may be considered a benign training‐related ECG phenomenon with a potential dynamic pattern.

Evaluation of the Seattle and International Criteria in elite Nigerian athletes

BACKGROUND

The Seattle Criteria (SC) and International Criteria (IC) were both developed for cardiovascular pre-participation screening in young athletes. Neither set of Criteria has been systematically evaluated in high level indigenous black African athletes.

OBJECTIVES

(1) To determine the pattern of ECG findings in athletes of the University of Port Harcourt, Nigeria; (2) To determine the predictors of altered repolarization in these athletes; and (3) To evaluate the diagnostic performance of the SC and IC in these athletes.

METHODS

77 athletes (42 males, 35 females) without any known cardiovascular disease were recruited alongside 78 similarly healthy non-athletic controls (44 males, 34 females). The two groups were matched for age, sex, and body mass index. Clinical assessment was according to the Lausanne Recommendations. All subjects underwent electrocardiography and echocardiography. Analysis with the IC was retrospective.

RESULTS

The most common physiological finding in the athletes was sinus bradycardia (n = 37; 48.1%). Early repolarization pattern, ERP (n = 27, 35.1% with SC; n = 42, 54.5% with IC), and dome-shaped ST-segment elevation with T-wave inversion (DSSTWI) in leads V1-4 (n = 21, 29.3% with both criteria), were also prevalent. Compared to controls, only male sex (adjusted odds ratio 2.89, 1.05 to 7.97, p = .040 with SC; OR 2.57, 1.19 to 5.53, p = .016 with IC) and ECG LVH (OR 2.82, 1.18 to 6.75, p = .020 with SC alone) independently predicted ERP, while athletic status (OR 4.76, 1.66 to 13.68, p = .004 with both criteria) alone had a significant multivariate association with DSSTWI. Three athletes (3.9%) had abnormal ECGs while two (2.6%) had major echocardiographic abnormalities. The sensitivity, specificity and accuracy of the SC for structural cardiac disease in the athletes were 50.0% (1.3 to 98.7), 97.3% (90.7 to 99.7) and 96.1% (89.0 to 99.2) respectively. The respective figures for the IC were 50.0% (1.3 to 98.7), 98.7% (92.8 to 100) and 97.4% (90.9 to 99.7).

CONCLUSION

Both criteria showed high accuracy in this Black African cohort with a high frequency of electrocardiographic repolarization changes. While ERP seems to be primarily related to black ethnicity, DSSTWI appears to be a bona fide marker of Athlete's Heart in blacks.

The significance of upright T wave in lead V1 in predicting myocardial ischemia A literature review

Chest pain is still representing one of the most common and serious presentations to the emergency department worldwide. ECG is a crucial tool in evaluating patients with chest pain; however, only around 50% of patients with acute coronary syndrome (ACS) will have a diagnostic ECG upon their presentation; the rest may either have a completely normal ECG or what is called nonspecific ST segment and T wave (NSSTTW) changes, hence it is essential to recognize the subtle ECG changes and know its significance. One of the ECG changes that can be easily missed is when the T wave in V1 is upright, especially when it is either a Tall Upright T wave (TTV1) or a New Tall Upright T-wave (NTTV1). Although upright T wave in lead V1 can be a normal variant, it has been linked in a few studies and observations to cardiovascular disease, especially myocardial ischemia. In this article, we are trying to highlight the importance of this subtle ECG change in predicting cardiovascular disease through a concise review of the available evidence on this topic.

Drug Therapy for Vagally-Mediated Atrial Fibrillation and Sympatho-Vagal Balance in the Genesis of Atrial Fibrillation: A Review of the Current Literature

Objective

The presence of both sympathetic activation-mediated triggers and parasympathetic activation-mediated substrates are required to initiate and maintain some forms of atrial fibrillation (AF). AF predominantly precipitated by parasympathetic stimulation is known as vagally-mediated AF (VM-AF). The role of novel drugs and molecular targeted gene therapy that modulate the autonomic nervous system are therapeutic options in this unique population with VM-AF. Here, we review the role of the sympatho-vagal balance in the genesis of AF and consider drug therapy for VM-AF.

Methods

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement, literature search was conducted using the keywords "vagal", "vagal nerve", "vagus", "vagus nerve", and "atrial fibrillation". Retrieved citations were first screened independently by 2 reviewers for inclusion and exclusion criteria.

Results

A total of 14 studies and 3 practice guidelines from 1986-2017 were included. Only two clinical investigations evaluated the effectiveness of disopyramide and sotalol in human subjects with VM-AF. The potential role of antiarrhythmic drugs has been studied in animal models.

Conclusions

Growing evidence suggests that the autonomic nervous system is integral in the development of VM-AF. Novel medications and genetic targets are undergoing investigation with promising results.

Cardiac Risk of Extreme Exercise

Habitual moderate intensity exercise is a vital component of a healthy lifestyle. For most of the population, increasing exercise duration and intensity beyond current recommendations appears to impart additional cardiovascular benefits; however, recent data has raised the possibility of an inflection point after which additional exercise no longer imparts benefit and may even result in negative cardiovascular outcomes. Exercise at the extremes of human endurance places a large hemodynamic stress on the heart and results in occasionally profound cardiac remodeling in order to accommodate the huge increases in cardiac output demanded by such endeavors. These changes have the potential to become maladaptive and heighten the risk of various arrhythmias, influence the rate of coronary atherosclerosis, and alter the risk of sudden cardiac death. Herein, we will discuss the potential negative impact of extreme exercise on cardiovascular risk.