Significance of false negative electrocardiograms in preparticipation screening of athletes for hypertrophic cardiomyopathy

Patterns of Electrocardiographic Abnormalities in Children with Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM), a common cardiomyopathy in children, is an important cause of morbidity and mortality. Early recognition and appropriate management are important. An electrocardiogram (ECG) is often used as a screening tool in children to detect heart disease. The ECG patterns in children with HCM are not well described.ECGs collected from an international cohort of children, and adolescents (≤ 21 years) with HCM were reviewed. 482 ECGs met inclusion criteria. Age ranged from 1 day to 21 years, median 13 years. Of the 482 ECGs, 57 (12%) were normal. The most common abnormalities noted were left ventricular hypertrophy (LVH) in 108/482 (22%) and biventricular hypertrophy (BVH) in 116/482 (24%) Of the patients with LVH/BVH (n = 224), 135 (60%) also had a strain pattern (LVH in 83, BVH in 52). Isolated strain pattern (in the absence of criteria for hypertrophy) was seen in 43/482 (9%). Isolated pathologic Q waves were seen in 71/482 (15%). Pediatric HCM, 88% have an abnormal ECG. The most common ECG abnormalities were LVH or BVH with or without strain. Strain pattern without hypertrophy and a pathologic Q wave were present in a significant proportion (24%) of patients. Thus, a significant number of children with HCM have ECG abnormalities that are not typical for "hypertrophy". The presence of the ECG abnormalities described above in a child should prompt further examination with an echocardiogram to rule out HCM.

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.

Can we screen for heart disease in children at public health centres? A multicentre observational study of screening for heart disease with a risk of sudden death in children

Sudden cardiac death in children is a rare event, but of great social significance. Generally, it is related to heart disease with a risk of sudden cardiac death (SCD), which may occur with cardiovascular symptoms and/or electrocardiographic markers; thus, a primary care paediatrician (PCP) could detect them. Therefore, we proposed a study that assesses how to put into practice and conduct a cardiovascular assessment within the routine healthy-child check-ups at six and twelve years of age; that reflects cardiovascular signs and symptoms, as well as the electrocardiographic alterations that children with a risk of SCD in the selected population present; and that assesses the PCP's skill at electrocardiogram (ECG) interpretation. In collaboration with PCPs, primary care nurses, and paediatric cardiologists, an observational, descriptive, multicentre, cross-sectional study was carried out in the Balearic Islands (Spain), from April 2021 to January 2022, inclusive. The PCPs gathered patient data through forms (medical record, electrocardiogram, and physical examination) and sent them to the investigator, together with the informed consent document and electrocardiogram. The investigator passed the electrocardiogram on to the paediatric cardiologists for reading, in an identical form to those the paediatricians had filled in. The variables were collected, and a descriptive analysis performed. Three paediatric cardiologists, twelve PCPs, and nine nurses from seven public health centres took part. They collected the data from 641 patients, but 233 patients did not participate (in 81.11% due to the PCP's workload). Therefore, the study coverage was around 64%, representing the quotient of the total number of patients who participated, divided by the total number of patients who were eligible for the study. We detected 30 patients with electrocardiographic alterations compatible with SCD risk. Nine of these had been examined by a paediatric cardiologist at some time (functional murmur in 8/9), five had reported shortness of breath with exercise, and four had reported a family history of sudden death. The physical examination of all the patients whose ECG was compatible with a risk of SCD was normal. Upon analysing to what extent the ECG results of the PCP and the paediatric cardiologist agreed, the percentage of agreement in the final interpretation (normal/altered) was 91.9%, while Cohen's kappa coefficient was 31.2% (CI 95%: 13.8-48.6%). The sensitivity of the ECG interpretation by the PCP to detect an ECG compatible with a risk of SCD was 29% and the positive predictive value 45%.     Conclusions: This study lays the foundations for future SCD risk screening in children, performed by PCPs. However, previously, it would be important to optimise their training in reading and interpreting paediatric ECGs. What is Known: • In Spain at present, there is a programme in place to detect heart disease with a risk of sudden death [1], but it targets only children who are starting on or are doing a physical activity as a federated sport. Implementing such screening programmes has proven effective in several countries [2]. However, several studies showed that the incidence of sudden cardiac death is no higher in children competing in sport activities than in those who do not do any sport [3]. This poses an ethical conflict, because at present, children who do not do any federated sport are excluded from screening. According to the revised literature, so far, only in two studies did they screen the child population at schools, and in both, they successfully detected patients with heart disease associated to the risk of sudden death [4, 5]. We have found no studies where the screening of these features was included within the routine healthy-child check-ups by primary care paediatricians. What is New: • We did not know whether-in our setting, at present-the primary care paediatrician could perform a screening method within the routine healthy-child check-ups, in order to detect presumably healthy children at risk of sudden cardiac death, as they present one of the SCD risks. In this regard, we proposed our project: to assess how to put into practice and conduct a cardiovascular assessment via SCD risk screening in the healthy child population by primary care paediatricians and appraise primary care paediatricians' skills in identifying the electrocardiographic alterations associated with SCD risk. The ultimate intention of this pilot study was to make it possible, in the future, to design and justify a study aimed at universalising cardiovascular screening and achieving a long-term decrease in sudden cardiac death events in children.

Cardiac Magnetic Resonance Feature-Tracking Identifies Preclinical Abnormalities in Hypertrophic Cardiomyopathy Sarcomere Gene Mutation Carriers

BACKGROUND

Assessing myocardial strain by cardiac magnetic resonance feature tracking (FT) has been found to be useful in patients with overt hypertrophic cardiomyopathy (HCM). Little is known, however, of its role in sarcomere gene mutation carriers without overt left ventricular hypertrophy (subclinical HCM).

METHODS

Thirty-eight subclinical HCM subjects and 42 healthy volunteers were enrolled in this multicenter case-control study. They underwent a comprehensive cardiac magnetic resonance study. Two-dimensional global radial, circumferential, and longitudinal strain of the left ventricle (LV) were evaluated by FT analysis.

RESULTS

The subclinical HCM sample was 41 (22-51) years old and 32% were men. FT analysis revealed a reduction in global radial strain (29±7.2 versus 47.9±7.4; P<0.0001), global circumferential strain (-17.3±2.6 -versus -20.8±7.4; P<0.0001) and global longitudinal strain (-16.9±2.4 versus -20.5±2.6; P<0.0001) in subclinical HCM compared with control subjects. The significant differences persisted when considering the 23 individuals free of all the structural and functional ECG and cardiac magnetic resonance abnormalities previously described. Receiver operating characteristic curve analyses showed that the differential diagnostic performances of FT in discriminating subclinical HCM from normal subjects were good to excellent (global radial strain with optimal cut-off value of 40.43%: AUC, 0.946 [95% CI, 0.93-1.00]; sensitivity 90.48%, specificity 94.44%; global circumferential strain with cut-off, -18.54%: AUC, 0.849 [95% CI, 0.76-0.94]; sensitivity, 88.10%; specificity, 72.22%; global longitudinal strain with cut-off, -19.06%: AUC, 0.843 [95% CI, 0.76-0.93]; sensitivity, 78.57%; specificity, 78.95%). Similar values were found for discriminating those subclinical HCM subjects without other phenotypic abnormalities from healthy volunteers (global radial strain with optimal cut-off 40.43%: AUC, 0.966 [95% CI, 0.92-1.00]; sensitivity, 90.48%; specificity, 95.45%; global circumferential strain with cut-off, -18.44%: AUC, 0.866 [95% CI, 0.76-0.96]; sensitivity, 92.86%; specificity, 77.27%; global longitudinal strain with cut-off, -17.32%: AUC, 0.838 [95% CI, 0.73-0.94]; sensitivity, 90.48%; specificity, 65.22%).

CONCLUSIONS

Cardiac magnetic resonance FT-derived parameters are consistently lower in subclinical patients with HCM, and they could emerge as a good tool for discovering the disease during a preclinical phase.

The pivotal role of ECG in cardiomyopathies

Cardiomyopathies are a heterogeneous group of pathologies characterized by structural and functional alterations of the heart. Recent technological advances in cardiovascular imaging offer an opportunity for deep phenotypic and etiological definition. Electrocardiogram (ECG) is the first-line diagnostic tool in the evaluation of both asymptomatic and symptomatic individuals. Some electrocardiographic signs are pathognomonic or fall within validated diagnostic criteria of individual cardiomyopathy such as the inverted T waves in right precordial leads (V1-V3) or beyond in individuals with complete pubertal development in the absence of complete right bundle branch block for the diagnosis of arrhythmogenic cardiomyopathy of the right ventricle (ARVC) or the presence of low voltages typically seen in more than 60% of patients with amyloidosis. Most other electrocardiographic findings such as the presence of depolarization changes including QRS fragmentation, the presence of epsilon wave, the presence of reduced or increased voltages as well as alterations in the repolarization phase including the negative T waves in the lateral leads, or the profound inversion of the T waves or downsloping of the ST tract are more non-specific signs which can however raise the clinical suspicion of cardiomyopathy in order to initiate a diagnostic procedure especially using imaging techniques for diagnostic confirmation. Such electrocardiographic alterations not only have a counterpart in imaging investigations such as evidence of late gadolinium enhancement on magnetic resonance imaging, but may also have an important prognostic value once a definite diagnosis has been made. In addition, the presence of electrical stimulus conduction disturbances or advanced atrioventricular blocks that can be seen especially in conditions such as cardiac amyloidosis or sarcoidosis, or the presence of left bundle branch block or posterior fascicular block in dilated or arrhythmogenic left ventricular cardiomyopathies are recognized as a possible expression of advanced pathology. Similarly, the presence of ventricular arrhythmias with typical patterns such as non-sustained or sustained ventricular tachycardia of LBBB morphology in ARVC or non-sustained or sustained ventricular tachycardia with an RBBB morphology (excluding the "fascicular pattern") in arrhythmogenic left ventricle cardiomyopathy could have a significant impact on the course of each disease. It is therefore clear that a learned and careful interpretation of ECG features can raise suspicion of the presence of a cardiomyopathy, identify diagnostic "red flags" useful for orienting the diagnosis toward specific forms, and provide useful tools for risk stratification. The purpose of this review is to emphasize the important role of the ECG in the diagnostic workup, describing the main ECG findings of different cardiomyopathies.

Tandem deep learning and logistic regression models to optimize hypertrophic cardiomyopathy detection in routine clinical practice

Background

An electrocardiogram (ECG)-based artificial intelligence (AI) algorithm has shown good performance in detecting hypertrophic cardiomyopathy (HCM). However, its application in routine clinical practice may be challenging owing to the low disease prevalence and potentially high false-positive rates.

Objective

Identify clinical characteristics associated with true- and false-positive HCM AI-ECG results to improve its clinical application.

Methods

We reviewed the records of the 200 patients with highest HCM AI-ECG scores in January 2021 at our institution. Logistic regression was used to create a clinical variable-based "Candidacy for HCM Detection (HCM-DETECT)" score, differentiating true-positive from false-positive AI-ECG results. We validated the HCM-DETECT score in an independent cohort of 200 patients with the highest AI-ECG scores from January 2022.

Results

In the 2021 cohort (median age 71 [interquartile range 58-80] years, 48% female), the rates of true-positive, false-positive, and indeterminate AI-ECG results for HCM detection were 36%, 48%, and 16%, respectively. In the 2022 cohort, the rates were 26%, 47%, and 27%, respectively. The HCM-DETECT score included age, coronary artery disease, prior pacemaker, and prior cardiac valve surgery, and had an area under the receiver operating characteristic curve of 0.81 (95% confidence interval 0.73-0.87) for differentiating true- vs false-positive AI results. When the 2022 cohort was limited to HCM detection candidates identified with the HCM-DETECT score, the false-positive AI-ECG rate was reduced from 47% to 13.5%.

Conclusion

Application of a clinical score (HCM-DETECT) in tandem with an AI-ECG model improved HCM detection yield, reducing the false-positive rate of AI-ECG more than 3-fold.

Accuracy of the "International Criteria" for ECG screening in athletes in comparison with previous published criteria: rationale and design of a diagnostic meta-analysis

INTRODUCTION

The impact of the International Criteria for ECG interpretation in athletes has further improved the diagnostic accuracy of the 12-lead ECG use for preparticipation screening (PPS); moreover, these criteria have been evaluated in different populations of athletes and settings proving good results.

EVIDENCE ACQUISITION

We aimed to perform a comprehensive review of the use of the International Criteria for ECG interpretation in athletes, stemming from a systematic review to diagnostic meta-analysis, limiting our inclusion only to observational studies to determine the diagnostic accuracy of ECG for detecting cardiac anomalies related to sudden cardiac death in athletes.

EVIDENCE SYNTHESIS

This meta-analysis is expected to include several important studies related to PPS on different populations of athletes comparing different ECG criteria and detail important data on the diagnostic accuracy of ECG in PPS. Furthermore, we intend to highlight the advantage of using ECG in PPS.

CONCLUSIONS

The present diagnostic meta-analysis results will aid sports medicine physicians and cardiologist in adhering to the most accurate criteria for ECG evaluation in athletes and it may help to solve controversies aroused regarding the excess cost of ECG in PPS related to the amount of false positive cases.

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.

Recommendations for Multimodality Cardiovascular Imaging of Patients with Hypertrophic Cardiomyopathy: An Update from the American Society of Echocardiography, in Collaboration with the American Society of Nuclear Cardiology, the Society for Cardiovascular Magnetic Resonance, and the Society of Cardiovascular Computed Tomography

Hypertrophic cardiomyopathy (HCM) is defined by the presence of left ventricular hypertrophy in the absence of other potentially causative cardiac, systemic, syndromic, or metabolic diseases. Symptoms can be related to a range of pathophysiologic mechanisms including left ventricular outflow tract obstruction with or without significant mitral regurgitation, diastolic dysfunction with heart failure with preserved and heart failure with reduced ejection fraction, autonomic dysfunction, ischemia, and arrhythmias. Appropriate understanding and utilization of multimodality imaging is fundamental to accurate diagnosis as well as longitudinal care of patients with HCM. Resting and stress imaging provide comprehensive and complementary information to help clarify mechanism(s) responsible for symptoms such that appropriate and timely treatment strategies may be implemented. Advanced imaging is relied upon to guide certain treatment options including septal reduction therapy and mitral valve repair. Using both clinical and imaging parameters, enhanced algorithms for sudden cardiac death risk stratification facilitate selection of HCM patients most likely to benefit from implantable cardioverter-defibrillators.

Differences in Atrial Remodeling in Hypertrophic Cardiomyopathy Compared to Hypertensive Heart Disease and Athletes' Hearts

Background: Hypertrophic cardiomyopathy (HCM), hypertensive heart disease (HHD) and athletes’ heart share an increased prevalence of atrial fibrillation. Atrial cardiomyopathy in these patients may have different characteristics and help to distinguish these conditions. Methods: In this single-center study, we prospectively collected and analyzed electrocardiographic (12-lead ECG, signal-averaged ECG (SAECG), 24 h Holter ECG) and echocardiographic data in patients with HCM and HHD and in endurance athletes. Patients with atrial fibrillation were excluded. Results: We compared data of 27 patients with HCM (70% males, mean age 50 ± 14 years), 324 patients with HHD (52% males, mean age 75 ± 5.5 years), and 215 endurance athletes (72% males, mean age 42 ± 7.5 years). HCM patients had significantly longer filtered P-wave duration (153 ± 26 ms) and PR interval (191 ± 48 ms) compared to HHD patients (144 ± 16 ms, p = 0.012 and 178 ± 31, p = 0.034, respectively) and athletes (134 ± 14 ms, p = 0.001 and 165 ± 26 ms, both p < 0.001, respectively). HCM patients had a mean of 4.9 ± 16 premature atrial complexes per hour. Premature atrial complexes per hour were significantly more frequent in HHD patients (27 ± 86, p < 0.001), but not in athletes (2.7 ± 23, p = 0.639). Left atrial volume index (LAVI) was 43 ± 14 mL/m2 in HCM patients and significantly larger than age- and sex-corrected LAVI in HHD patients 30 ± 10 mL/m2; p < 0.001) and athletes (31 ± 9.5 mL/m2; p < 0.001). A borderline interventricular septum thickness ≥13 mm and ≤15 mm was found in 114 (35%) HHD patients, 12 (6%) athletes and 3 (11%) HCM patients. Conclusions: Structural and electrical atrial remodeling is more advanced in HCM patients compared to HHD patients and athletes.

Feasibility of a Novel Strategy for Cardiovascular Screening During the Preparticipation Physical Examination

OBJECTIVE

To determine the feasibility of simultaneously conducting history and physical (H&P), limb-lead electrocardiogram (ECG), and preparticipation echocardiography by frontline providers (PEFP) at one screening station.

METHODS

This cross-sectional study compares limb-lead versus 12-lead ECG as part of a preparticipation physical examination (PPE) including H&P and PEFP conducted in year 1 and year 2 on 2 cohorts (n = 36, n = 53, respectively) of college athletes at one institution. Year 1 screening was conducted at 3 stations, one station per screening component. Time to complete each station was recorded, and total time for screening was the summation of times for each station. Year 2 screening was conducted at one station; timing began when the patient entered the room and ended when all 3 components of screening were complete. An unpaired t test was used to compare the mean time difference between years 1 and 2 screening stations.

RESULTS

Year 1 screening time was significantly longer than time to complete cardiac screening using the year 2 protocol (10.51 ± 1.98 vs 3.96 ± 1.43 minutes, respectively; P < 0.001). Five athletes in year 1 and 3 athletes in year 2 were referred to cardiology for further evaluation; all athletes were ultimately cleared to participate.

CONCLUSIONS

A comprehensive PPE can be completed in a timely fashion using a single screening station and limb-lead ECG to improve efficiency, while still allowing providers to gather information on history, physical examination, heart rhythm, and heart structure. This strategy may serve as a potential solution in the longstanding debate over best practices for PPEs.

Hypertrophic Cardiomyopathy: Updates Through the Lens of Sports Cardiology

Purpose of review

This review will summarize the distinction between hypertrophic cardiomyopathy (HCM) and exercise-induced cardiac remodeling (EICR), describe treatments of particular relevance to athletes with HCM, and highlight the evolution of recommendations for exercise and competitive sport participation relevant to individuals with HCM.

Recent findings

Whereas prior guidelines have excluded individuals with HCM from more than mild-intensity exercise, recent data show that moderate-intensity exercise improves functional capacity and indices of cardiac function and continuation of competitive sports may not be associated with worse outcomes. Moreover, recent studies of athletes with implantable cardioverter defibrillators (ICDs) demonstrated a safer profile than previously understood. In this context, the updated American Heart Association/American College of Cardiology (AHA/ACC) and European Society of Cardiology (ESC) HCM guidelines have increased focus on shared decision-making and liberalized restrictions on exercise and sport participation among individuals with HCM.

Summary

New data demonstrating the safety of exercise in individuals with HCM and in athletes with ICDs, in addition to a focus on shared decision-making, have led to the most updated guidelines easing restrictions on exercise and competitive athletics in this population. Further athlete-specific studies of HCM, especially in the context of emerging therapies such as mavacamten, are important to inform accurate risk stratification and eligibility recommendations.

Etiology of Sudden Cardiac Arrest and Death in US Competitive Athletes: A 2-Year Prospective Surveillance Study

OBJECTIVE

To determine the etiology of sudden cardiac arrest and death (SCA/D) in competitive athletes through a prospective national surveillance program.

DESIGN

Sudden cardiac arrest and death cases in middle school, high school, college, and professional athletes were identified from July 2014 to June 2016 through traditional and social media searches, reporting to the National Center for Catastrophic Sports Injury Research, communication with state and national high school associations, review of the Parent Heart Watch database, and search of student-athlete deaths on the NCAA Resolutions List. Autopsy reports and medical records were reviewed by a multidisciplinary panel to determine the underlying cause.

SETTING AND PARTICIPANTS

US competitive athletes with SCA/D.

MAIN OUTCOME MEASURES

Etiology of SCA/D.

RESULTS

A total of 179 cases of SCA/D were identified (74 arrests with survival, 105 deaths): average age 16.6 years (range 11-29), 149 (83.2%) men, 94 (52.5%) whites, and 54 (30.2%) African American. One hundred seventeen (65.4%) had an adjudicated diagnosis, including 83 deaths and 34 survivors. The most common etiologies included hypertrophic cardiomyopathy (19, 16.2%), coronary artery anomalies (16, 13.7%), idiopathic left ventricular hypertrophy/possible cardiomyopathy (13, 11.1%), autopsy-negative sudden unexplained death (8, 6.8%), Wolff-Parkinson-White (8, 6.8%), and long QT syndrome (7, 6.0%). Hypertrophic cardiomyopathy was more common in male basketball (23.3%), football (25%), and African American athletes (30.3%). An estimated 56.4% of cases would likely demonstrate abnormalities on an electrocardiogram.

CONCLUSIONS

The etiology of SCA/D in competitive athletes involves a wide range of clinical disorders. More robust reporting mechanisms, standardized autopsy protocols, and accurate etiology data are needed to better inform prevention strategies.

Interpretation of T-wave inversion in physiological and pathological conditions: Current state and future perspectives

The presence of T‐wave inversion (TWI) at 12‐lead electrocardiogram (ECG) in competitive athletes is one of the major diagnostic challenges for sports physicians and consulting cardiologists. Indeed, while the presence of TWI may be associated with some benign conditions and it may be occasionally seen in healthy athletes presenting signs of cardiac remodeling, it may also represent an early sign of an underlying, concealed structural heart disease or life‐threatening arrhythmogenic cardiomyopathies, which may be responsible for exercise‐related sudden cardiac death (SCD). The interpretation of TWI in athletes is complex and the inherent implications for the clinical practice represent a conundrum for physicians. Accordingly, the detection of TWI should be viewed as a potential red flag on the ECG of young and apparently healthy athletes and warrants further investigations because it may represent the initial expression of cardiomyopathies that may not be evident until many years later and that may ultimately be associated with adverse outcomes. The aim of this review is, therefore, to report an update of the literature on TWI in athletes, with a specific focus on the interpretation and management.

Electrocardiographic changes and long-term prognosis of children diagnosed with hypertrophic cardiomyopathy by the school screening program for heart disease in Japan

BACKGROUND

In Japan, the school screening program for heart disease (SS) has been performed since 1973. However, little has been reported on the electrocardiogram (ECG) changes and long-term prognosis in patients with hypertrophic cardiomyopathy (HCM) detected by the SS.

METHODS

All 44 consecutive pediatric HCM patients (10.1 ± 3.0 years old), who had been originally consulted by the SS before the diagnosis of HCM from April 1981 to April 2017, were reviewed retrospectively.

RESULTS

At the SS, all patients showed mild or no symptoms. All patients showed ECG abnormalities, and 75 % had a high proposed ECG risk score (≧6). However, 30 % of them had no echocardiogram finding of myocardial hypertrophy. During the follow-up period (14.8 ± 10.0 years), life-threatening events (LTE) occurred in 11 (25 %) patients, and the first LTE occurred during exercise in 8 (18 %). The estimated LTE and heart failure death-free survival rate at 10 years was 64.9 %. The LTE-free survival rate was lower in patients without than in those with myocardial hypertrophy at the SS.

CONCLUSIONS

The SS was useful in detecting patients with HCM with mild or no symptoms at the early stage. However, our study indicated that early detection of HCM is not associated with improvement in the prognosis of the patients. Further studies are needed.

International recommendations for electrocardiographic interpretation in athletes

Sudden cardiac death (SCD) is the leading cause of mortality in athletes during sport. A variety of mostly hereditary, structural, or electrical cardiac disorders are associated with SCD in young athletes, the majority of which can be identified or suggested by abnormalities on a resting 12-lead electrocardiogram (ECG). Whether used for diagnostic or screening purposes, physicians responsible for the cardiovascular care of athletes should be knowledgeable and competent in ECG interpretation in athletes. However, in most countries a shortage of physician expertise limits wider application of the ECG in the care of the athlete. A critical need exists for physician education in modern ECG interpretation that distinguishes normal physiological adaptations in athletes from distinctly abnormal findings suggestive of underlying pathology. Since the original 2010 European Society of Cardiology recommendations for ECG interpretation in athletes, ECG standards have evolved quickly over the last decade; pushed by a growing body of scientific data that both tests proposed criteria sets and establishes new evidence to guide refinements. On 26-27 February 2015, an international group of experts in sports cardiology, inherited cardiac disease, and sports medicine convened in Seattle, Washington, to update contemporary standards for ECG interpretation in athletes. The objective of the meeting was to define and revise ECG interpretation standards based on new and emerging research and to develop a clear guide to the proper evaluation of ECG abnormalities in athletes. This statement represents an international consensus for ECG interpretation in athletes and provides expert opinion-based recommendations linking specific ECG abnormalities and the secondary evaluation for conditions associated with SCD.

The electrocardiogram in the diagnosis and management of patients with hypertrophic cardiomyopathy

In an era of rapid technological development and evolving diagnostic possibilities, the electrocardiogram (ECG) is living an authentic "renaissance" in myocardial diseases. To date, the ECG remains an irreplaceable first step when evaluating patients with hypertrophic cardiomyopathy (HCM) and an abnormal ECG may be the only manifestation of disease at an early stage. In some instances, specific electrical anomalies may differentiate HCM from phenocopies such as cardiac amyloidosis and glycogen storage diseases. The exponential growth in knowledge of the complexity of HCM has led to new challenges in terms of early identification of the disease, differential diagnosis, risk stratification, and development of targeted therapies. In this scenario, the apparently "old fashioned" ECG and the array of ECG-based techniques, ranging from Holter monitoring and loop recorders to exercise testing, are as contemporary as ever. In the present review, we discuss the current role of the ECG in the diagnosis and management of HCM, focusing on various clinical settings where its appropriate use and interpretation can make a difference.

There is No Reason to Adopt ECG s and Abandon American Heart Association/American College of Cardiology History and Physical Screening for Detection of Cardiovascular Disease in the Young

See Article Williams et al.

Continuous electrocardiogram changes preceding phenotypic expression for 8 years in an athlete with hypertrophic cardiomyopathy: a case report

Background

Hypertrophic cardiomyopathy is one of the most common causes of sudden cardiac death in young athletes. Performing, comparing, and monitoring serial electrocardiograms over time can help to detect potential cardiovascular diseases and to prevent malignant cardiac events in these populations.

Case presentation

A young Han Chinese male football player had abnormal electrocardiograms for 8 years without any subjective discomfort. Electrocardiograms revealed that T-wave inversions increased from 1 mm to a maximum of 5 mm on lead I and fluctuated around 5 mm on lead avL. Q-wave duration ranged from 40 ms to 60 ms, its depth increased to a maximum of 8 mm and was much greater than 40% of the R waves in depth in II, III, and avF leads. Echocardiography showed increasingly thickened interventricular septum from 10 mm to 13 mm, enlarged left atrium and ventricle, and reduced left ventricular ejection fraction. Coronary angiography showed no distinct stenosis. Emission computed tomography revealed mild myocardial ischemia of the left ventricular inferior wall. These unusual electrocardiogram manifestations were initially regarded as benign alterations of a highly trained athlete. Upon reviewing the clinical information and the newest criteria for electrocardiographic interpretation in athletes, hypertrophic cardiomyopathy was identified. The misreading of electrocardiograms is not uncommon, thus predisposing such patients to high susceptibility to exercise-induced sudden cardiac death.

Conclusions

We propose that abnormal electrocardiogram findings reveal the initial expression of underlying cardiac diseases such as hypertrophic cardiomyopathy, preceding the symptoms and signs by many years. Accordingly, early detection and continuous surveillance are important for athletes with such electrocardiogram patterns, and improvement of physicians’ expertise is crucial.

Sudden cardiac death in football players: Towards a new pre-participation algorithm

Athletic pre-participation screening is essential for minimizing the risk for sudden cardiac death (SCD) in athletes participating in either competitive or leisure sporting activities. The primary causes of SCD in young athletes (<35 years of age) include hypertrophic cardiomyopathy, congenital anomalies of the coronary artery and arrhythmogenic right ventricular cardiomyopathy. Other abnormalities, such as malignant arrhythmia due to blunt trauma to the chest (commotio cordis), myocarditis, valvular disease, aortic rupture (in Marfan syndrome) and ion channelopathies (catecholaminergic polymorphic ventricular tachycardia, Brugada syndrome, long or short QT syndrome), also contribute to a lesser degree to SCD. Currently, clinical assessment, electrocardiogram (ECG) and echocardiography are the cornerstones of the pre-participation athletic evaluation. However, their low sensitivity raises queries as regards the need for the application of more sophisticated modalities, such as cardiovascular magnetic resonance (CMR). CMR offers precise biventricular assessment and is greatly reproducible without the inherent limitations of echocardiography; i.e., low quality of images due to the lack of appropriate acoustic window or operator's experience. Furthermore, myocardium replacement fibrosis, indicative of patients' increased risk for future cardiac events, can be effectively detected by late gadolinium enhanced (LGE) images, acquired 15 min post-contrast injection. Finally, diffuse myocardial fibrosis not identified by LGE, can also be detected by pre-contrast (native) T1, post-contrast T1 mapping and extracellular volume images, which provide detailed information about the underlying pathophysiologic background. Therefore, CMR is recommended in all football players with a positive family or personal history of syncope or SCD, abnormal/doubtful ECG or echocardiogram.

Electrocardiography in athletes: normal and abnormal findings

Many sporting organisations recommend a pre-participation ECG to screen for disorders which predispose to sudden cardiac arrest (SCA). The ability of the ECG to perform accurately is dependent on the ECG criteria used and the experience of the operator. There have been several ECG criteria over the last decade, though these were recently superseded with the publication of the 'International Consensus Criteria for ECG Interpretation in Athletes'. These criteria use the latest evidence to improve specificity while maintaining sensitivity for ECG-detectable pathologies associated with SCA. Accordingly, this review describes the normal, borderline and abnormal ECG findings in an asymptomatic athlete aged 12-35 years.

Women with hypertrophic cardiomyopathy have worse survival

Aims

Sex differences in hypertrophic cardiomyopathy (HCM) remain unclear. We sought to characterize sex differences in a large HCM referral centre population.

Methods and results

Three thousand six hundred and seventy-three adult patients with HCM underwent evaluation between January 1975 and September 2012 with 1661 (45.2%) female. Kaplan-Meier survival curves were assessed via log-rank test. Cox proportional hazard regression analyses evaluated the relation of sex with survival. At index visit, women were older (59 ± 16 vs. 52 ± 15 years, P < 0.0001) had more symptoms [New York Heart Association (NYHA) Class III-IV 45.0% vs. 35.3%, P < 0.0001], more obstructive physiology (77.4% vs. 71.8%, P = 0.0001), more mitral regurgitation (moderate or greater in 56.1% vs. 43.9%, P < 0.0001), higher E/e' ratio (n = 1649, 20.6 vs. 15.6, P < 0.0001), higher estimated pulmonary artery systolic pressure (n = 1783, 40.8 ± 15.4 vs. 34.8 ± 10.8 mmHg, P < 0.0001), worse cardiopulmonary exercise performance (n = 1267; percent VO2 predicted 62.8 ± 20% vs. 65.8 ± 19.2%, P = 0.007), and underwent more frequent alcohol septal ablation (4.9% vs. 3.0%, P = 0.004) but similar frequency of myectomy (28% vs. 30%, P = 0.24). Median follow-up was 10.9 (IQR 7.4-16.2) years. Kaplan-Meier analysis demonstrated lower survival in women compared with men (P < 0.0001). In multivariable modelling, female sex remained independently associated with mortality (HR 1.13 [1.03-1.22], P = 0.01) when adjusted for age, NYHA Class III-IV symptoms, and cardiovascular comorbidities.

Conclusion

Women with HCM present at more advanced age, with more symptoms, worse cardiopulmonary exercise tolerance, and different haemodynamics than men. Sex is an important determinant in HCM management as women with HCM have worse survival. Women may require more aggressive diagnostic and therapeutic approaches.

Early Screening for Cardiovascular Abnormalities With Preparticipation Echocardiography: Feasibility Study

OBJECTIVE

The traditional history and physical (H&P) is a poor screening modality to identify athletes at risk for sudden cardiac death. Although better than H&P alone, electrocardiograms (ECG) have also been found to have high false-positive rates. A limited portable echocardiogram by a frontline physician (PEFP) performed during preparticipation physical examination (PPE) allows for direct measurements of the heart to more accurately identify athletes with structural abnormalities. Therefore, it is worthwhile to assess the feasibility of incorporating limited PEFP as part of PPEs. The aim of this study was to investigate the feasibility of incorporating limited screening PEFP into routine PPEs.

METHODS

Thirty-five Division I male collegiate athletes were prospectively enrolled in the study after informed consent was obtained. Each athlete underwent screening with H&P, ECG, and limited PEFP. The H&P was performed based on the 2007 twelve-element preparticipation cardiovascular screening guidelines from the American Heart Association. The ECGs were interpreted using the 2013 Seattle Criteria. The limited echocardiographic (ECHO) measurements were obtained in the parasternal long axis view. End-diastolic measurements were recorded for the left ventricular diameter (LVD), left ventricular posterior wall diameter (LVPWd), interventricular septal wall diameter (IVSWd), aortic root diameter, and ascending aorta. The length of time of each screening station was recorded and reported in seconds (sec) and compared by one-way repeated-measures of analysis of variance with pairwise Bonferroni correction. A priori alpha level was set as 0.05.

RESULTS

The length of time for screening was significantly shorter with limited PEFP (137.7 ± 40.4 seconds) compared with H&P (244.2 ± 80.0 seconds) and ECG (244.9 ± 85.6 seconds, P < 0.01). The screening time did not differ between H&P and ECG (P = 0.97). Six athletes had a positive finding in H&P screening and 3 athletes had positive ECG findings. One athlete had both a positive H&P and screening ECG. All 3 athletes with positive ECGs had negative limited PEFP screens. One athlete had a borderline posterior wall thickness (1.49 mm) on the limited screening PEFP evaluation and another was found to have a borderline IVSWd-to-LVPWd ratio (1.28). All 3 athletes with positive ECG findings and both athletes with a borderline finding on limited PEFP were referred for formal evaluation with a cardiologist. None of the 5 athletes were disqualified from competition after cardiac evaluation, but 1 of the athletes with a positive screening-limited ECHO needs annual monitoring.

CONCLUSIONS

Incorporating limited PEFP into PPEs has the potential to limit the number of false-positive and false-negative cardiac screens. Limited PEFP was the fastest screening modality compared with traditional H&P and ECG methods. Based on the time-driven activity-based paradigm of cost analysis, limited PEFP as part of the PPE yields the highest value: the most accurate and reliable information and the lowest dollar/time expenditure.

International Recommendations for Electrocardiographic Interpretation in Athletes

Sudden cardiac death (SCD) is the leading cause of mortality in athletes during sport. A variety of mostly hereditary, structural, or electrical cardiac disorders are associated with SCD in young athletes, the majority of which can be identified or suggested by abnormalities on a resting 12-lead electrocardiogram (ECG). Whether used for diagnostic or screening purposes, physicians responsible for the cardiovascular care of athletes should be knowledgeable and competent in ECG interpretation in athletes. However, in most countries a shortage of physician expertise limits wider application of the ECG in the care of the athlete. A critical need exists for physician education in modern ECG interpretation that distinguishes normal physiological adaptations in athletes from distinctly abnormal findings suggestive of underlying pathology. Since the original 2010 European Society of Cardiology recommendations for ECG interpretation in athletes, ECG standards have evolved quickly over the last decade; pushed by a growing body of scientific data that both tests proposed criteria sets and establishes new evidence to guide refinements. On February 26-27, 2015, an international group of experts in sports cardiology, inherited cardiac disease, and sports medicine convened in Seattle, Washington, to update contemporary standards for ECG interpretation in athletes. The objective of the meeting was to define and revise ECG interpretation standards based on new and emerging research and to develop a clear guide to the proper evaluation of ECG abnormalities in athletes. This statement represents an international consensus for ECG interpretation in athletes and provides expert opinion-based recommendations linking specific ECG abnormalities and the secondary evaluation for conditions associated with SCD.

Accuracy of the ECG for differential diagnosis between hypertrophic cardiomyopathy and athlete’s heart: comparison between the European Society of Cardiology (2010) and International (2017) criteria

Background

Interpretation of the athlete’s ECG is based on differentiation between benign ECG changes and potentially pathological abnormalities. The aim of the study was to compare the 2010 European Society of Cardiology (ESC) and the 2017 International criteria for differential diagnosis between hypertrophic cardiomyopathy (HCM) and athlete’s heart.

Methods

The study populations included 200 patients with HCM and 563 athletes grouped as follows: ‘group 1’, including normal ECG and isolated increase of QRS voltages, which are considered non-pathologic according to ESC and International criteria; ‘group 2’, including left atrial enlargement or left axis deviation in isolation and Q-waves with an amplitude ≥4 mm but <25% of the ensuing R-wave and a duration <0.04 s which are considered pathologic according to the ESC but not according to the International criteria; and ‘group 3’, including abnormalities which are considered pathologic according to ESC and International criteria.

Results

Overall, the 2010 ESC criteria showed a sensitivity of 95.5% and a specificity of 86.9%. Considering group 2 ECG changes as normal according to the International criteria led to a statistically significant (p<0.001) increase of specificity to 95.9%, associated with a non-significant (p=0.47) reduction of sensitivity to 93%. Among patients with HCM, there was a significant increase of maximal left ventricular wall thickness from group 1 to 3 (p=0.02).

Conclusions

The use of 2017 International criteria is associated with a substantial increase in specificity and a marginal decrease in sensitivity for differential diagnosis between HCM and athlete’s heart.

International criteria for electrocardiographic interpretation in athletes: Consensus statement

Sudden cardiac death (SCD) is the leading cause of mortality in athletes during sport. A variety of mostly hereditary, structural or electrical cardiac disorders are associated with SCD in young athletes, the majority of which can be identified or suggested by abnormalities on a resting 12-lead electrocardiogram (ECG). Whether used for diagnostic or screening purposes, physicians responsible for the cardiovascular care of athletes should be knowledgeable and competent in ECG interpretation in athletes. However, in most countries a shortage of physician expertise limits wider application of the ECG in the care of the athlete. A critical need exists for physician education in modern ECG interpretation that distinguishes normal physiological adaptations in athletes from distinctly abnormal findings suggestive of underlying pathology. Since the original 2010 European Society of Cardiology recommendations for ECG interpretation in athletes, ECG standards have evolved quickly, advanced by a growing body of scientific data and investigations that both examine proposed criteria sets and establish new evidence to guide refinements. On 26-27 February 2015, an international group of experts in sports cardiology, inherited cardiac disease, and sports medicine convened in Seattle, Washington (USA), to update contemporary standards for ECG interpretation in athletes. The objective of the meeting was to define and revise ECG interpretation standards based on new and emerging research and to develop a clear guide to the proper evaluation of ECG abnormalities in athletes. This statement represents an international consensus for ECG interpretation in athletes and provides expert opinion-based recommendations linking specific ECG abnormalities and the secondary evaluation for conditions associated with SCD.

Selective use of the electrocardiogram in pediatric preparticipation athletic examinations among pediatric primary care providers

OBJECTIVES

Recent literature examining insurance administrative data suggests that a selective approach, with concurrent history and physical exam (H&P), for obtaining an electrocardiogram (ECG) as a part of a preparticipation examination (PPE) for pediatric athletes is commonly used in the primary care setting demonstrating a high rate of disease detection. We sought to understand practice patterns of providers with regard to usage of ECG as a part of PPE.

METHODS

Utilizing an online survey, we queried primary care providers regarding their practice patterns, rationale, and concerns regarding use of ECGs as a part of the PPE.

RESULTS

A total of 125 pediatricians completed the survey; 73.7% selectively use the ECG, 24.6% never use the ECG, and only 1.7% always obtain an ECG as part of the PPE. The most common rationale for selectively or never using the ECG is the belief that the H&P is sufficient to identify cardiac disease (70%). The most common H&P findings that lead to ECG screening include chest pain or syncope with exertion, family history of sudden cardiac death, an irregular heart rate, and a diastolic murmur. Among the diseases associated with sudden cardiac death, most pediatricians fear missing hypertrophic cardiomyopathy.

CONCLUSION

Based on a survey of primary care providers, most practitioners are utilizing a selective approach of obtaining an ECG as a part of a PPE for athletic participation, which is in agreement with the current American Heart Association guidelines. Significant practice variation continues to exist, and may represent an area for future resource optimization.

Discrimination of the "Athlete's Heart" from real disease by electrocardiogram and echocardiogram

Chronic physical training has been shown to produce multiple changes in the heart, resulting in the athlete's heart phenotype. Some of the changes can make it difficult to discern athlete's heart from true cardiac disease, most notably hypertrophic cardiomyopathy. Other diseases such as dilated cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy may be difficult to rule in or out. In this article, the physiological cardiac changes of chronic athletic training are reviewed. A methodological approach using electrocardiography and echocardiography to differentiate between athlete's heart and cardiac disease is proposed.

Electrocardiographic abnormalities in elite high school athletes: comparison to adolescent hypertrophic cardiomyopathy

BACKGROUND

In athletes, ECG changes from physiological cardiac remodelling are common but can overlap with findings from a pathological disorder. We compared ECG findings in a group of elite high school athletes to a cohort of adolescents with hypertrophic cardiomyopathy (HCM).

METHODS/RESULTS

We prospectively performed 15-lead ECGs and echocardiograms in 147 elite high school athletes. Student-athlete ECGs were compared in blinded fashion to ECGs of 148 adolescents with HCM of similar age and ethnicity. Standard ECG hypertrophy criteria and established expert opinion guidelines (European Society of Cardiology, ESC and Seattle criteria) were analysed. All student-athletes had normal echocardiograms. Overall, 77/147 (52%) of student-athletes met standard ECG criteria for ventricular hypertrophy compared to 126/148 (85%) adolescents with HCM (p<0.0001). There were 112/148 (76%) adolescents with HCM who had pathological Q-waves, T-wave inversion and/or ST-segment depression compared to 1/147 (1%) athletes (p<0.0001). Most patients with HCM (84%, 124/148) had ≥1 abnormal ECG finding(s) according to Seattle criteria, compared to 1% of student-athletes (2/147). Similarly, 130/148 (88%) patients with HCM met group-2 ESC criteria (abnormal), compared to 36/147 (24%) student-athletes (p<0.0001).

CONCLUSIONS

Over 50% of elite high school athletes with echocardiographically confirmed normal hearts satisfied standard voltage criteria for ventricular hypertrophy. Pathological Q-waves, T-wave inversion or ST-segment depression were most helpful in distinguishing adolescents with HCM from normals. Both ESC and Seattle criteria successfully stratified the student-athlete and HCM cohorts, however each had a false-negative rate >10% for the HCM cohort. The Seattle criteria demonstrated a significantly lower false-positive rate (1%) than the ESC criteria (24%).

The Evidence Against Cardiac Screening Using Electrocardiogram in Athletes

Sudden cardiac death (SCD) in young athletes is publicly remarkable and tragic because of the loss of a seemingly healthy young person. Because many of the potential etiologies may be identified with a preparticipation electrocardiogram (ECG), the possible use of an ECG as a screening tool has received much attention. A good screening test should be cost-effective and should influence a disease or health outcome that has a significant impact on public health. The reality is that the prevalence of SCD is low and no outcome-based data exist to determine whether early detection saves lives. Further, there is insufficient screening infrastructure, and the risk of screening and follow-up may be higher than that of the actual disease. Until outcomes data demonstrate a benefit with regard to SCD, universal screening cannot be recommended.

Cardiovascular Screening in Young Athletes: Evidence for the Electrocardiogram

: The objective of this study is to review the evidence for cardiovascular screening inclusive of an electrocardiogram (ECG) in young athletes. Sudden cardiac death (SCD) in athletes is the leading cause of death during exercise and occurs at a rate that is substantially higher than initially recognized. There is widespread agreement that cardiovascular screening should be performed prior to athletic competition. The primary purpose of preparticipation cardiovascular screening is to identify athletes with conditions that predispose them to SCD. Unfortunately, the traditional model in the United States of a medical history and a physical examination has limited sensitivity to detect cardiovascular disease and provides false reassurance to athletes, parents, and team officials. The addition of an ECG enhances the ability to identify disease, and modern athlete-specific ECG interpretation standards used by experienced physicians provide low false-positive rates, improving the cost-effectiveness while preserving sensitivity. The evidence is clear that if athletes are screened, ECG-inclusive strategies are most likely to meet the primary aim of preparticipation cardiovascular screening. These advanced protocols have the potential to improve health and safety during sport events and should be considered the best practice in high-risk athletes when the sports cardiology infrastructure and oversight are readily available.

Differentiating hypertrophic cardiomyopathy from athlete's heart: An electrocardiographic and echocardiographic approach

Differential diagnosis of hypertrophic cardiomyopathy (HCM) vs athlete's heart is challenging in individuals with mild-moderate left-ventricular hypertrophy. This study aimed to assess ECG and echocardiographic parameters proposed for the differential diagnosis of HCM. The study included 75 men in three groups: control (n=30), "gray zone" athletes with interventricular septum (IVS) measuring 13-15mm (n=25) and HCM patients with IVS of 13-18mm (n=20). The most significant differences were found in relative septal thickness (RST), calculated as the ratio of 2 x IVS to left ventricle end-diastolic diameter (LV-EDD) (0.37, 0.51, 0.71, respectively; p<0.01) and in spatial QRS-T angle as visually estimated (9.8, 33.6, 66.2, respectively; p<0.01). The capacity for differential HCM diagnosis of each of the 5 criteria was assessed using the area under the curve (AUC), as follows: LV-EDD<54 (0.60), family history (0.61), T-wave inversion (TWI) (0.67), spatial QRS-T angle>45 (0.75) and RST>0.54 (0.92). Pearson correlation between spatial QRS-T angle>45 and TWI was 0.76 (p 0.01). The combination of spatial QRS-T angle>45 and RST>0.54 for diagnosis of HCM had an AUC of 0.79. The best diagnostic criteria for HCM was RST>0.54. The spatial QRS-T angle>45 did not add sensitivity if TWI was present. No additional improvement in differential diagnosis was obtained by combining parameters.

Sensibilidade e especificidade do exame eletrocardiográfico na detecção de sobrecargas atriais e/ou ventriculares em gatos da raça Persa com cardiomiopatia hipertrófica

Resumo: A cardiomiopatia hipertrófica (CMH) é a principal cardiopatia dos felinos e é caracterizada por hipertrofia miocárdica concêntrica, sem dilatação ventricular. O ecocardiograma é o melhor meio diagnóstico não invasivo para a diferenciação das cardiomiopatias e é considerado padrão ouro para a detecção de hipertrofia ventricular presente na CMH. Alterações eletrocardiográficas também são comuns em animais com CMH e o eletrocardiograma (ECG) é um teste de triagem para detecção de hipertrofia ventricular em humanos, sendo um exame rápido e facilmente disponível. Em gatos, poucos estudos foram realizados quanto à sensibilidade e especificidade do ECG na detecção de hipertrofia ventricular. Com a intenção de avaliar o uso do ECG como ferramenta de triagem para diagnóstico de CMH em felinos, gatos da raça Persa (n=82) foram avaliados por meio de exames ecocardiográfico e eletrocardiográfico. Animais com bloqueios e/ou distúrbios de condução foram excluídos da análise estatística (n=22). Posteriormente, os animais incluídos foram classificados em: normais (n=38), suspeitos (n=6) e acometidos pela CMH (n=16). Observaram-se diferenças estatísticas na amplitude da onda P em DII e na amplitude de onda R em DII, CV6LL e CV6LU, com valores maiores nos animais com CMH; e nos valores ecocardiográficos de velocidade e gradiente de pressão do fluxo aórtico, diâmetro do átrio esquerdo (AE) e relação AE/Ao, com valores maiores nos gatos com CMH. Dentre os animais com alterações eletrocardiográficas sugestivas de sobrecarga atrial esquerda (n=7), apenas dois realmente apresentavam aumento do AE no ecocardiograma; e dentre os animais com aumento atrial esquerdo ao ecocardiograma (n=7), apenas dois apresentavam alterações eletrocardiográficas sugestivas de sobrecarga do AE (sensibilidade de 40,40% e especificidade de 90,90%). Dentre os gatos com alterações eletrocardiográficas sugestivas de sobrecarga ventricular esquerda (n=6), cinco realmente apresentavam hipertrofia ventricular ao ecocardiograma; e dentre os animais com CMH ao ecocardiograma (n=16), apenas cinco apresentaram alterações eletrocardiográficas sugestivas de sobrecarga do VE (sensibilidade de 31,25% e especificidade de 97,72%). Observou-se correlação positiva entre espessura diastólica do septo interventricular e/ou da parede livre do ventrículo esquerdo e a amplitude da onda R em derivações DII e CV6LU. O eletrocardiograma é um exame rápido e de fácil execução, apresenta boa especificidade na detecção de hipertrofia ventricular em felinos, porém, possui baixa sensibilidade, com grande número de falsos negativos. Desta forma, o ECG auxilia no diagnóstico, mas não substitui o ecocardiograma na confirmação da hipertrofia ventricular.

Screening of athletes: An electrocardiogram is not enough

Professional and amateur athletic training can cause tremendous overload of the cardiovascular system and thus become a trigger of serious and often fatal cardiac events in athletes with a previously undetected underlying cardiovascular disease. Therefore, every athlete should undergo a specialized diagnostic and qualification screening before a training program is prescribed or continued. However, it is still an unresolved issue which of the accessible diagnostic tools should be routinely applied in order to increase the safety of extreme physical training and reduce the risk of sudden cardiac death. Pre-participation athlete evaluation including a standard electrocardiogram (ECG), physical examination, and familial history of cardiovascular diseases is important, but does not always guarantee high diagnostic accuracy. Hence, the aim of this review article is to discuss the controversy over the usefulness of ECG for the detection of cardiovascular diseases in athletes as well as the views on athlete screening methods in Europe and the USA. Differential diagnostic options and screening schemes are also described in particular groups of athletes in reference to their age, cardiovascular risk factors, as well as intensity and type of sport discipline.

Morphological and Electrical Characteristics in Patient with Hypertrophic Cardiomyopathy: Quantitative Analysis of 864 Korean Cohort

PURPOSE

Although several studies have reported the morphological and electrical characteristics in patients with hypertrophic cardiomyopathy (HCM), comparison between asymmetric and apical HCM has not been investigated in a reasonably sized cohort.

MATERIALS AND METHODS

Echocardiography and electrocardiography were quantitatively analyzed in patients with HCM in a Korean tertiary referral center.

RESULTS

Of 864 patients (mean age 55.4±14.2 years, 68.9% men), 255 (29.5%) patients had apical HCM, 553 (64.0%) patients asymmetric HCM, and 56 (6.4%) patients mixed type HCM. In echocardiographic evaluations, about three quarters of patients (75.8%) had left atrial enlargement. Left ventricular (LV) dilatations and systolic dysfunction were observed in 6.1% and 2.4%, respectively. QRS widening, PR prolongation, and pathologic Q wave are frequent in patients with asymmetric HCM, while LV strain is frequent in patient with apical HCM. The prevalence of J-point elevations (9.4% in inferior, 2.2% in lateral leads) were substantially higher than that in general population. Giant negative T wave was observed in 15.0% of total patients (32.2% in apical, 6.2% in asymmetric, 25% in mixed type). There was no significant correlation between the thickness of the apical wall and the amplitude of T wave inversion (r=-0.005, p=0.71).

CONCLUSION

In a large cohort of HCM including apical type, repolarization abnormalities, including early repolarization and QT prolongation as well as LV strain, were significantly observed. T wave inversion was not appropriate for screening of HCM and not correlated with apical wall thickness.

Screening young athletes for prevention of sudden cardiac death: Practical recommendations for sports physicians

Regular intensive exercise in athletes increases the relative risk of sudden cardiac death (SCD) compared with the relatively sedentary population. Most cases of SCD are due to silent cardiovascular diseases, and pre-participation screening of athletes at risk of SCD is thus of major importance. However, medical guidelines and recommendations differ widely between countries. In Italy, the National Health System recommends pre-participation screening for all competitive athletes including personal and family history, a physical examination, and a resting 12-lead electrocardiogram (ECG). In the United States, the American College of Cardiology and the American Heart Association recommend a pre-participation screening program limited to the use of specific questionnaires and a clinical examination. The value of a 12-lead ECG is debated based on issues surrounding cost-efficiency and feasibility. The aim of this review was to focus on (i) the incidence rate of cardiac diseases in relation to SCD; (ii) the value of conducting a questionnaire and a physical examination; (iii) the value of a 12-lead resting ECG; (iv) the importance of other cardiac evaluations in the prevention of SCD; and (v) the best practice for pre-participation screening.

Normal Variant T-Wave Changes in an Athlete with Structurally Normal Cardiac Anatomy and Function

Athletes who perform regular and intensive physical activity may undergo structural and electrical remodeling of the heart that results in electrocardiographic changes that can cause concern. Marked T-wave inversion may represent one such physiologic change. On the other hand, T-wave inversion could be a sign of inherited heart muscle disease or may be a normal variant. Therefore, it is imperative to determine whether abnormalities on an athlete's electrocardiography (ECG) reflect underlying cardiac disease that could place the athlete at risk for sudden cardiac death. For athletes who present with markedly abnormal ECGs, the echocardiography and cardiac magnetic resonance imaging should be considered to evaluate the potential for cardiac disease. We report the case of a high-intensity athlete with concerning ECG changes who required additional studies to exclude cardiac disease.

Echocardiography in the evaluation of athletes

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

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

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

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