Screening for hypertrophic cardiomyopathy in a young male military population

Re-evaluating the Incidence and Prevalence of Clinical Hypertrophic Cardiomyopathy: An Epidemiological Study of Olmsted County, Minnesota

OBJECTIVE

To contemporaneously reappraise the incidence-rate, prevalence, and natural history of hypertrophic cardiomyopathy (HCM) in Olmsted County, Minnesota, from 1984 to 2015.

PATIENTS AND METHODS

A validated medical-record linkage system collecting information for residents of Olmsted County was used to identify all cases of HCM between January 1, 1984, and December 31, 2015. After adjudication of records from Mayo Clinic and Olmsted Medical Center, data relating to diagnoses and outcomes were abstracted. The calculated incidence rate and prevalence were standardized to the US 1980 White population (age- and sex-adjusted) and compared with a prior study examining the years 1975-1984.

RESULTS

Two hundred seventy subjects with HCM were identified. The age- and sex-adjusted incidence rate was 6.6 per 100,000 person-years, and the point prevalence of HCM on January 1, 2016, was 89 per 100,000 population. The incidence rate and point prevalence of HCM on January 1, 2016, standardized to the US 1980 White population (age- and sex-adjusted), were 6.7 (95% CI, 7.1 to 8.8) per 100,000 person-years and 81.5 per 100,000 population, respectively. The incidence rate of HCM increased each decade since the index study. Individuals with HCM had a higher overall standardized mortality rate than the general population with an observed to expected HR of 1.44 (95% CI, 1.21 to 1.71; P<.001) which improved by each decade.

CONCLUSION

The incidence and prevalence of HCM are higher than rates reported from a prior study in the same community examining the years 1975-1984, but lower than other study cohorts. The risk of mortality in HCM remains higher than expected, albeit with improvement in rates of mortality observed each decade during the study period.

Targeted therapies in genetic dilated and hypertrophic cardiomyopathies: From molecular mechanisms to therapeutic targets

Genetic cardiomyopathies are disorders of the cardiac muscle, most often explained by pathogenic mutations in genes encoding sarcomere, cytoskeleton, or ion channel proteins. Clinical phenotypes such as heart failure and arrhythmia are classically treated with generic drugs, but aetiology‐specific and targeted treatments are lacking. As a result, cardiomyopathies still present a major burden to society, and affect many young and older patients. The Translational Committee of the Heart Failure Association (HFA) and the Working Group of Myocardial Function of the European Society of Cardiology (ESC) organized a workshop to discuss recent advances in molecular and physiological studies of various forms of cardiomyopathies. The study of cardiomyopathies has intensified after several new study setups became available, such as induced pluripotent stem cells, three‐dimensional printing of cells, use of scaffolds and engineered heart tissue, with convincing human validation studies. Furthermore, our knowledge on the consequences of mutated proteins has deepened, with relevance for cellular homeostasis, protein quality control and toxicity, often specific to particular cardiomyopathies, with precise effects explaining the aberrations. This has opened up new avenues to treat cardiomyopathies, using contemporary techniques from the molecular toolbox, such as gene editing and repair using CRISPR‐Cas9 techniques, antisense therapies, novel designer drugs, and RNA therapies. In this article, we discuss the connection between biology and diverse clinical presentation, as well as promising new medications and therapeutic avenues, which may be instrumental to come to precision medicine of genetic cardiomyopathies.

Clinical Characteristics for the Improvement of Cushing's Syndrome Complicated With Cardiomyopathy After Treatment With a Literature Review

Background: Endogenous Cushing's syndrome (CS), also called hypercortisolism, leads to a significant increase in mortality due to excessive cortisol production, which is mainly due to cardiovascular disease. CS complicated with cardiomyopathies, which is a rare and severe condition, has rarely been reported in the literature. Objective: To investigate the clinical characteristics of CS complicated with cardiomyopathies, we retrospectively reviewed the clinical manifestations, laboratory results, cardiac imaging results and prognosis to further understand the diagnosis, treatment, and management of these cases. Methods: The clinical data of patients diagnosed with CS complicated with cardiomyopathies obtained from discharge sheets from Peking Union Medical College Hospital from January 1986 to August 2021 were collected. Case reports of CS complicated with cardiomyopathies were retrieved from PubMed. In addition, Cushing's disease (CD) patients without cardiomyopathies were collected as controls to compare the clinical features. Results: A total of 19 cases of CS complicated with cardiomyopathies and cases of CD without cardiomyopathies (n = 242) were collected. The causes of CS included pituitary adenoma (n = 8, 42.11%), adrenal adenoma (n = 7, 36.84%), ectopic adrenocorticotropic hormone (ACTH) tumor (n = 2, 10.53%) and unclear causes (n = 2, 10.53%) in the CS complicated with cardiomyopathies group. The types of cardiomyopathies were dilated cardiomyopathies (n = 15, 78.94%) and hypertrophic cardiomyopathies (n = 4, 21.05%). The serum sodium concentration was significantly higher [145.50 (140.50-148.00) mmol/L vs. 141.00 (140.00-143.00) mmol/L], while the serum potassium concentration was significantly lower [2.70 (2.40-3.60) mmol/L] vs. 3.90 (3.50-4.20 mmol/L)] in the CS complicated with cardiomyopathies group compared to the CD patients without cardiomyopathies. There were no significant differences between the CS complicated with cardiomyopathies group and the CD patients without cardiomyopathies in the serum cortisol concentration and 24-h urine free cortisol, but a significant difference in the adrenocorticotropic hormone level [109.00 (91.78-170.30) pg/ml vs. 68.60 (47.85-110.00) pg/ml]. Twelve/16 (75.0%) patients showed significant improvement or even a complete healing of the heart structure and function after remission of hypercortisolemia after treatment with CS. Conclusions: CS complicated with cardiomyopathies is a very rare clinical entity, in which cortisol plays an important role and it can be greatly improved after remission of hypercortisolemia.

Role of global longitudinal strain in discriminating variant forms of left ventricular hypertrophy and predicting mortality

OBJECTIVE

In this study, we aimed to compare the functional adaptations of the left ventricle in variant forms of left ventricular hypertrophy (LVH) and to evaluate the use of two-dimensional speckle tracking echocardiography (2D-STE) in differential diagnosis and prognosis.

METHODS

This was a prospective cohort study of 68 patients with LVH, including 20 patients with non-obstructive hypertrophic cardiomyopathy (HCM), 23 competitive top-level athletes free of cardiovascular disease, and 25 patients with hypertensive heart disease (HHD). All the subjects underwent 2D transthoracic echocardiography (TTE) and 2D-STE. The primary endpoint was all-cause mortality. Global longitudinal strain (GLS) below -12.5% was defined as severely reduced strain, -12.5% to -17.9% as mildly reduced strain, and above -18% as normal strain.

RESULTS

The mean LV-GLS value was higher in athletes than in patients with HCM and HHD with the lowest value being in the HCM group (HCM: -11.4±2.2%; HHD: -13.6±2.6%; and athletes: -15.5±2.1%; p<0.001 among groups). LV-GLS below -12.5% distinguished HCM from others with 65% sensitivity and 77% specificity [area under curve (AUC)=0.808, 95% confidence interval (CI): 0.699-0.917, p<0.001]. The median follow-up duration was 6.4±1.1 years. Overall, 11 patients (16%) died. Seven of these were in the HHD group, and four were in the HCM group. The mean GLS value in patients who died was -11.8±1.5%. LV-GLS was significantly associated with mortality after adjusting age and sex via multiple analysis (RR=0.723, 95% CI: 0.537-0.974, p=0.033). Patients with GLS below -12.5% had a higher risk of all-cause mortality compared with that of patients with GLS above -12.5% according to Kaplan-Meier survival analysis for 7 years (29% vs. 9%; p=0.032). The LV-GLS value predicts mortality with 64% sensitivity and 70% specificity with a cut-off value of -12.5 (AUC=0.740, 95% CI: 0.617-0.863, p=0.012).

CONCLUSION

The 2D-STE provides important information about the longitudinal systolic function of the myocardium. It may enable differentiation variable forms of LVH and predict prognosis.

Routine pre-employment echocardiography assessment in young adults: cost and benefits

Background

Conventional echocardiography is a safe, available, and accurate tool for cardiac structural and functional evaluation, but it should not cancel clinical assessment and history tacking, and indeed both are complementary. A pre-employment assessment is important for employees and community safety and suitability for a specific work requirement.

Results

Aiming to assess the value of routine pre-employment echocardiography for the detection of cardiac abnormalities, we examined seven hundred ninety-five persons who were routinely referred to us for pre-employment conventional echocardiography. Only 9 persons had structural cardiac abnormalities (1.3%) and distributed as follows: two had bicuspid aortic valve with isolated aortic regurgitation, one of them had mild AR, and the other had moderate AR. Two cases had mitral valve prolapse, one of them had trivial MR, while the other had a flail anterior leaflet with severe MR. One patient had atrial septal defect 1.5 cm with mild pulmonary hypertension and right-sided chambers dilatation. One patient had dextrocardia (situs inversus totalis) without other cardiac problems. One had moderate pulmonary hypertension and modest right-sided chambers dilation. Two patients had left ventricular hypertrophy. Surprisingly, we did not detect rheumatic valvular heart disease. The money cost of echocardiography tests for those 795 persons was 198,750 Egyptian pounds (LE); their transportation cost was about 19.800LE. The total group time cost of the tests was 265 h, total time lost at the waiting room was 1590 h, total transportation time lose was 2385 h, so the total time cost was about 4000 h. Using psychological stress questionnaire, 33 participants (4.2%) had results suggestive of a low sense of psychological pressure due to echocardiography examination, 221 participants (27.8%) had results suggestive of a moderate feeling of stress, while 541 participants (68%) had results suggestive of a high sense of stress.

Conclusion

We recommend against routine echocardiography for cardiac assessment in pre-employment assessment and to do it only for persons with abnormal clinical or ECG findings.

Epidemiology of cardiomyopathies: essential context knowledge for a tailored clinical work-up

Cardiomyopathies (CMPs) are primary disorders of myocardial structure and function in the absence of coronary artery disease, hypertension, valvular disease, and congenital heart disease. Knowledge of the incidence and prevalence of CMPs may help clinicians to compare their observations in clinical practice with expected cases per person-year and to avoid under-reporting in clinical context. Currently, available estimates of prevalence and incidence of CMPs are based on clinical data, collected with a wide variability in population-source, and before the genetic testing evolved as a standard diagnostic tool. This review focuses on the epidemiology of CMPs in subjects aged between 18 and 55 years. A structured up-to-date diagnostic flow-chart for CMPs diagnosis and assessment is proposed to avoid misdiagnosis of CMPs in the young population and in subjects with unexplained cardiac disorders.

Epidemiology of the inherited cardiomyopathies

In the absence of contemporary, population-based epidemiological studies, estimates of the incidence and prevalence of the inherited cardiomyopathies have been derived from screening studies, most often of young adult populations, to assess cardiovascular risk or to detect the presence of disease in athletes or military recruits. The global estimates for hypertrophic cardiomyopathy (1/500 individuals), dilated cardiomyopathy (1/250) and arrhythmogenic right ventricular cardiomyopathy (1/5,000) are probably conservative given that only individuals who fulfil diagnostic criteria would have been included. This caveat is highly relevant because a substantial minority or even a majority of individuals who carry disease-causing genetic variants and are at risk of disease complications have incomplete and/or late-onset disease expression. The genetic literature on cardiomyopathy, which is often focused on the identification of genetic variants, has been biased in favour of pedigrees with higher penetrance. In clinical practice, an abnormal electrocardiogram with normal or non-diagnostic imaging results is a common finding for the sarcomere variants that cause hypertrophic cardiomyopathy, the titin and sarcomere variants that cause dilated cardiomyopathy and the desmosomal variants that cause either arrhythmogenic right ventricular cardiomyopathy or dilated cardiomyopathy. Therefore, defining the genetic epidemiology is also challenging given the overlapping phenotypes, incomplete and age-related expression, and highly variable penetrance even within individual families carrying the same genetic variant.

Heart muscle disease management in aircrew

This manuscript focuses on the broad aviation medicine considerations that are required to optimally manage aircrew with suspected or confirmed heart muscle disease (both pilots and non-pilot aviation professionals). ECG abnormalities on aircrew periodic medical examination or presentation of a family member with a confirmed cardiomyopathy are the most common reason for investigation of heart muscle disease in aircrew. Holter monitoring and imaging, including cardiac MRI is recommended to confirm or exclude the presence of heart muscle disease and, if confirmed, management should be led by a subspecialist. Confirmed heart muscle disease often requires restriction toflying duties due to concerns regarding arrhythmia. Pericarditis and myocarditis usually require temporary restriction and return to flying duties is usually dependent on a lack of recurrent symptoms and acceptable imaging and electrophysiological investigations.

Sex-related differences in exercise performance and outcome of patients with hypertrophic cardiomyopathy

AIMS

Exercise performance is known to predict outcome in hypertrophic cardiomyopathy (HCM), but whether sex-related differences exist is unresolved. We explored whether functional impairment, assessed by exercise echocardiography, has comparable predictive accuracy in females and males with HCM.

METHODS

We retrospectively evaluated 292 HCM patients (46 ± 16 years, 72% males), consecutively referred for exercise echocardiography; 242 were followed for 5.9 ± 4.2 years.

RESULTS

Peak exercise capacity was 6.5 ± 1.6 metabolic equivalents (METs). Sixty patients (21%) showed impaired exercise capacity (≤5 METs). Exercise performance was reduced in females, compared with males (5.6 ± 1.6 vs 6.9 ± 1.5 METs, p < 0.001; peak METs ≤ 5 in 40% vs 13%, p < 0.001), largely driven by a worse performance in women >50 years of age. At multivariable analysis, female sex was independently associated with impaired exercise capacity (odds ratio: 4.67; 95% confidence interval (CI): 1.83-11.90; p = 0.001). During follow-up, 24 patients (10%) met the primary endpoint (a combination of cardiac death, heart failure requiring hospitalization, sustained ventricular tachycardia, appropriate implantable cardioverter defibrillator discharge, resuscitated sudden cardiac death and cardioembolic stroke). Event-free survival was reduced in females (p = 0.035 vs males). Peak METs were inversely related to outcome in males (hazard ratio (HR) per unit increase: 0.57; 95% CI: 0.39-0.84; p = 0.004) but not in females (HR: 1.22; 95% CI: 0.66-2.24; p = 0.53).

CONCLUSIONS

Female patients with HCM showed significant age-related impairment in functional capacity compared with males, particularly evident in post-menopausal age groups. While women were at greater risk of HCM-related complications and death, impaired exercise capacity predicted adverse outcome only in men. These findings suggest the need for sex-specific management strategies in HCM.

Prognostic role of clinical presentation in symptomatic patients with hypertrophic cardiomyopathy

AIMS

To evaluate the long-term prognostic impact of baseline symptoms in a cohort of hypertrophic cardiomyopathy (HCM) patients.

METHODS AND RESULTS

We considered 84 HCM patients symptomatic at diagnosis: 26 (31%) with heart failure (group 1), 34 (40%) with syncope/palpitations (group 2) and 24 (29%) with chest pain (group 3). During a median follow-up of 102 (53-187) months, 25 (30%) patients died/underwent heart transplant (HTx), 14 of 26 (54%) in group 1, 10 of 34 (29%) in group 2 and one of 24 (4%) in group 3. At 12, 60 and 120 months, HTx-free survival rates were 100, 79 and 52% in group 1, vs. 100, 97 and 69% in group 2, vs. 96, 96 and 96% in group 3, respectively (P = 0.008). At multivariate analysis, heart failure [hazard ratio (HR) 2.59, confidence interval (CI) 95% 1.09-6.17, P = 0.032] and left atrium diameter (HR 1.83, CI 95% 1.16-2.89, P = 0.009) emerged as independent predictors of death/HTx, with incremental prognostic power with respect to echo Doppler variables of left ventricular systolic and diastolic dysfunction [area under the curve (AUC) of receiver operating characteristics (ROC) curves at 5 years: 0.90 vs. 0.78, respectively, P = 0.03].

CONCLUSION

Clinical presentation emerged as a relevant prognostic tool in HCM patients symptomatic at onset, as heart failure was associated with a particularly poor outcome. Heart failure and left atrium diameter at diagnosis showed incremental prognostic power compared with echo Doppler assessment of left ventricular systolic and diastolic dysfunction.

Hypertrophic Cardiomyopathy: Prevalence, Hypertrophy Patterns, and Their Clinical and ECG Findings in a Hospital at Qatar

Background:

Hypertrophic cardiomyopathy (HCM) is a genetic disease associated with risk of morbidity and sudden cardiac death. The prevalence, hypertrophy patterns, mode of presentations, and different ECG findings vary in different regions of the world. To date, no data is present regarding these variables in Qatar.

Patients and Methods:

A retrospective, cross sectional, descriptive analysis of all patients referred for echocardiography study at Hamad General Hospital, Qatar. The study period was from January 2008 till December 2010.

Aims:

To study 1) the prevalence of HCM, 2) the different patterns of hypertrophy, and 3) the clinical and ECG presentations in this population.

Results:

Out of the 29,286 cases evaluated, 38 patients were found to have HCM (0.13%). Their clinical, ECG, and echocardiography findings were analyzed. Mean age was 47 y, 35 males (92%) and 3 females (8%). Four patterns of hypertrophy were described; 17 (44.7%) had septal hypertrophy alone, 6 (15.8%) had septal and other segments hypertrophy but sparing the apex, 10 (26.3%) had apical segments along with any other segment hypertrophy, and 5 (13.2%) had apical hypertrophy alone. No obstruction was found in 19 (50%), left ventricular outflow (LVO) tract obstruction was found in 13 (34%), and mid cavity obstruction (MCO) in 6 (16%). Twenty one (55.3%) patients were referred because of chest pain, 15 (39.5%) with palpitations, 15 (39.5%) with shortness of breath, and 5 (13.2%) with syncope. Nine patients (23.7%) were asymptomatic and were referred because of cardiac murmur during routine examination. ECG evidence of LV hypertrophy was found in 29 (76.3%).

Conclusion:

The prevalence of HCM in our population group is 0.13% with a male predominance (12:1). There was a diversity of clinical presentation, ECG abnormalities and patterns of LV hypertrophy among HCM patients.

Electrocardiogram screening for disorders that cause sudden cardiac death in asymptomatic children: a meta-analysis

BACKGROUND AND OBJECTIVES

Pediatric sudden cardiac death (SCD) occurs in an estimated 0.8 to 6.2 per 100 000 children annually. Screening for cardiac disorders causing SCD in asymptomatic children has public appeal because of its apparent potential to avert tragedy; however, performance of the electrocardiogram (ECG) as a screening tool is unknown. We estimated (1) phenotypic (ECG- or echocardiogram [ECHO]-based) prevalence of selected pediatric disorders associated with SCD, and (2) sensitivity, specificity, and predictive value of ECG, alone or with ECHO.

METHODS

We systematically reviewed literature on hypertrophic cardiomyopathy (HCM), long QT syndrome (LQTS), and Wolff-Parkinson-White syndrome, the 3 most common disorders associated with SCD and detectable by ECG.

RESULTS

We identified and screened 6954 abstracts, yielding 396 articles, and extracted data from 30. Summary phenotypic prevalences per 100 000 asymptomatic children were 45 (95% confidence interval [CI]: 10-79) for HCM, 7 (95% CI: 0-14) for LQTS, and 136 (95% CI: 55-218) for Wolff-Parkinson-White. The areas under the receiver operating characteristic curves for ECG were 0.91 for detecting HCM and 0.92 for LQTS. The negative predictive value of detecting either HCM or LQTS by using ECG was high; however, the positive predictive value varied by different sensitivity and specificity cut-points and the true prevalence of the conditions.

CONCLUSIONS

Results provide an evidence base for evaluating pediatric screening for these disorders. ECG, alone or with ECHO, was a sensitive test for mass screening and negative predictive value was high, but positive predictive value and false-positive rates varied.

Alcohol Septal Ablation for the Treatment of Hypertrophic Obstructive Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is an inherited myocardial disorder characterised by left ventricular hypertrophy. A subgroup of patients develops limiting symptoms in association with left ventricular outflow tract obstruction (LVOTO). Current international guidelines recommend that symptomatic patients are initially treated by alleviating exacerbating factors and negatively inotropic medication. Drug-refractory symptoms require a comprehensive evaluation of the mechanism of LVOTO and review by a multidisciplinary team to consider the relative merits of myectomy, alcohol septal ablation (ASA) and pacing. This article provides a brief overview of HCM and the pathophysiology of LVOTO, and reviews the use of ASA in patients with drug-refractory symptoms secondary to LVOTO.

Echocardiography in patients with hypertrophic cardiomyopathy: usefulness of old and new techniques in the diagnosis and pathophysiological assessment

Hypertrophic cardiomyopathy (HCM) is one of the most common inherited cardiomyopathy. The identification of patients with HCM is sometimes still a challenge. Moreover, the pathophysiology of the disease is complex because of left ventricular hyper-contractile state, diastolic dysfunction, ischemia and obstruction which can be coexistent in the same patient. In this review, we discuss the current and emerging echocardiographic methodology that can help physicians in the correct diagnostic and pathophysiological assessment of patients with HCM.

Cost-effectiveness of preparticipation screening for prevention of sudden cardiac death in young athletes

BACKGROUND

Inclusion of 12-lead electrocardiography (ECG) in preparticipation screening of young athletes is controversial because of concerns about cost-effectiveness.

OBJECTIVE

To evaluate the cost-effectiveness of ECG plus cardiovascular-focused history and physical examination compared with cardiovascular-focused history and physical examination alone for preparticipation screening.

DESIGN

Decision-analysis, cost-effectiveness model.

DATA SOURCES

Published epidemiologic and preparticipation screening data, vital statistics, and other publicly available data.

TARGET POPULATION

Competitive athletes in high school and college aged 14 to 22 years.

TIME HORIZON

Lifetime.

PERSPECTIVE

Societal.

INTERVENTION

Nonparticipation in competitive athletic activity and disease-specific treatment for identified athletes with heart disease.

OUTCOME MEASURE

Incremental health care cost per life-year gained.

RESULTS OF BASE-CASE ANALYSIS

Addition of ECG to preparticipation screening saves 2.06 life-years per 1000 athletes at an incremental total cost of $89 per athlete and yields a cost-effectiveness ratio of $42 900 per life-year saved (95% CI, $21 200 to $71 300 per life-year saved) compared with cardiovascular-focused history and physical examination alone. Compared with no screening, ECG plus cardiovascular-focused history and physical examination saves 2.6 life-years per 1000 athletes screened and costs $199 per athlete, yielding a cost-effectiveness ratio of $76 100 per life-year saved ($62 400 to $130 000).

RESULTS OF SENSITIVITY ANALYSIS

Results are sensitive to the relative risk reduction associated with nonparticipation and the cost of initial screening.

LIMITATIONS

Effectiveness data are derived from 1 major European study. Patterns of causes of sudden death may vary among countries.

CONCLUSION

Screening young athletes with 12-lead ECG plus cardiovascular-focused history and physical examination may be cost-effective.

PRIMARY FUNDING SOURCE

Stanford Cardiovascular Institute and the Breetwor Foundation.

The role of ECG screening in the evaluation of risk of sudden cardiac arrest in the young

We have the opportunity to answer the questions that have been raised and obtain answers by prospective evaluation. ECG screening does not need an all-or-none approach in the current era. It needs a commitment to obtain the relevant data that will be accepted as applicable in the United States. Multiple populations, genders, ages, ethnicities, and races should be screened in a prospective ECG screening study. The actual costs should be obtained and cost utility analysis should be performed. Models of screening should be developed and tested. It is no longer acceptable to say "It can't be done here"; or "It costs too much"; or any of the scores of excuses used unless one can support the statements with trials or scientific data. A study of 100,000 children ages 5-19 years would cost $500,000-750,000. Is it not worth finding out who is correct, how to better identify those at risk, and how to do it in the most cost-efficient manner? No one wants to waste $2 billion a year. However, a one-time investment of 25% of that amount would determine how best to use our health care resources in the future to identify children and youth at risk for SCA.

Sudden cardiac death in athletes: the Lausanne Recommendations

OBJECTIVES

This study reports on sudden cardiac death (SCD) in sport in the literature and aims at achieving a generally acceptable preparticipation screening protocol (PPSP) endorsed by the consensus meeting of the International Olympic Committee (IOC).

BACKGROUND

The sudden death of athletes under 35 years engaged in competitive sports is a well-known occurrence; the incidence is higher in athletes (approximately 2/100,000 per year) than in non-athletes (2.5 : 1), and the cause is cardiovascular in over 90%.

METHODS

A systematic review of the literature identified causes of SCD, sex, age, underlying cardiac disease and the type of sport and PPSP in use. Methods necessary to detect pre-existing cardiac abnormalities are discussed to formulate a PPSP for the Medical Commission of the IOC.

RESULTS

SCD occurred in 1101 (1966-2004) reported cases in athletes under 35 years, 50% had congenital anatomical heart disease and cardiomyopathies and 10% had early-onset atherosclerotic heart disease. Forty percent occurred in athletes under 18 years, 33% under 16 years; the female/male ratio was 1/9. SCD was reported in almost all sports; most frequently involved were soccer (30%), basketball (25%) and running (15%). The PPSP were of varying quality and content. The IOC consensus meeting accepted the proposed Lausanne Recommendations based on this research and expert opinions (http://multimedia.olympic.org/pdf/en_report_886.pdf).

CONCLUSION

SCD occurs more frequently in young athletes, even those under the age of 18 years, than expected and is predominantly caused by pre-existing congenital cardiac abnormalities. Premature atherosclerotic disease forms another important cause in these young adults. A generally acceptable PPSP has been achieved by the IOC's acceptance of the Lausanne Recommendations.

Electrocardiography and the preparticipation physical examination: is it time for routine screening?

The preparticipation physical examination (PPE) is a screening tool endorsed by numerous organizations and used to evaluate young athletes prior to competition for both medical and musculoskeletal conditions that may predispose them to injury. The cardiac portion of the examination, as recommended by the American Heart Association, is detailed specifically to detect signs or symptoms consistent with certain congenital heart conditions that may increase a young athlete's risk of sudden cardiac death (SCD). Much controversy has erupted over the years as to whether this examination has the diagnostic sensitivity to detect these conditions and prevent SCD, and whether additional modalities, such as the 12-lead electrocardiograph (ECG), should be incorporated. Given the rarity of SCD events, the large population of young athletes that would qualify yearly for the examination, and the limitations that an ECG would present, it would not be efficient to add the ECG to the standard PPE on the symptomatic athlete. More efforts should be spent in standardizing the PPE on a national level to further improve its efficiency.

The Italian Registry for hypertrophic cardiomyopathy: a nationwide survey

BACKGROUND

National registries are advocated as instrumental to the solution of rarity-related problems for patients with hypertrophic cardiomyopathy (HCM), including limited access to advanced treatment options. Thus, an Italian Registry for HCM was created to assess the clinical profile and the level of care nationwide of patients with HCM.

METHODS

Cardiology centers over the national territory were recruited to provide clinical data of all patients with HCM ever seen at each institution. The enrollment period was from May 2000 to May 2002.

RESULTS

The registry enrolled 1677 patients from 40 institutions. Most (69%) were followed at referral centers, whereas 31% were from community centers with intermediate-low patient flow. Patients diagnosed after routine medical examinations or familial screenings were 39%. Most patients were male (62%), in their fourth to sixth decade of life, and in New York Heart Association class I to II (89%); 24% had resting left ventricular obstruction and 18% had atrial fibrillation. During a 9.7-year average follow-up, cardiovascular mortality was 1%/y, mostly because of heart failure, with no significant change over the last 3 decades; sudden death was less common (0.4%/y). Only 4% of patients received a defibrillator; 14% of the 401 patients with LV outflow obstruction underwent invasive relief of obstruction; and <1% were offered genetic analyses or counseling.

CONCLUSIONS

The Italian Registry represents the first comprehensive attempt to evaluate the clinical impact and management of HCM at a national level. Findings underscore the role of screening strategies for an early diagnosis and suggest limited use of the advanced therapeutic options for HCM.

Gender-related differences in the clinical presentation and outcome of hypertrophic cardiomyopathy

OBJECTIVES

The goal of this study was to assess gender-related differences in a multicenter population with hypertrophic cardiomyopathy (HCM).

BACKGROUND

Little is known regarding the impact of gender on the heterogeneous clinical profile and clinical course of HCM.

METHODS

We studied 969 consecutive HCM patients from Italy and the U.S. followed over 6.2 +/- 6.1 years.

RESULTS

Male patients had a 3:2 predominance (59%), similar in Italy and the U.S. (p = 0.24). At initial evaluation, female patients were older and more symptomatic than male patients (47 +/- 23 years vs. 38 +/- 18 years; p < 0.001; mean New York Heart Association [NYHA] functional class 1.8 +/- 0.8 vs. 1.4 +/- 0.6; p < 0.001), and more frequently showed left ventricular outflow obstruction (37% vs. 23%; p < 0.001). Moreover, female patients were less often diagnosed fortuitously by routine medical examination (23% vs. 41% in male patients, p < 0.001). Female gender was independently associated with the risk of symptom progression to NYHA functional classes III/IV or death from heart failure or stroke compared with male gender (independent relative hazard 1.5; p < 0.001), particularly patients > or =50 years of age and with resting outflow obstruction (p < 0.005). Hypertrophic cardiomyopathy-related mortality and risk of sudden death were similar in men and women.

CONCLUSIONS

Women with HCM were under-represented, older, and more symptomatic than men, and showed higher risk of progression to advanced heart failure or death, often associated with outflow obstruction. These gender-specific differences suggest that social, endocrine, or genetic factors may affect the diagnosis and clinical course of HCM. A heightened suspicion for HCM in women may allow for timely implementation of treatment strategies, including relief of obstruction and prevention of sudden death or stroke.

Relation of electrocardiographic patterns to phenotypic expression and clinical outcome in hypertrophic cardiomyopathy

Twelve-lead electrocardiography, a traditional component in evaluations of patients with hypertrophic cardiomyopathy (HC), is often regarded as a marker for the magnitude of left ventricular (LV) hypertrophy, which in turn has been linked to sudden death risk. To determine whether electrocardiographic (ECG) patterns have clinical utility by accurately reflecting phenotypic expression or predicting clinical outcome, voltages and patterns were compared with LV wall thicknesses assessed by echocardiography and with clinical outcomes in 448 consecutive patients with HC. Significant but relatively weak correlations were evident between maximum LV wall thickness and ECG voltage: r = 0.295 (p <0.01) for the sum of R- and S-wave voltages in all 12 leads, r = 0.254 (p <0.01) for the maximum R or S wave in any lead, and r = 0.210 (p <0.01) for the sum of SV(1) (or SV(2)) and RV(5) (or RV(6)). Of 55 patients with extreme LV hypertrophy (LV wall thickness > or =30 mm), only 24 (44%) showed greatly increased ECG voltage > or =30 mm in any lead. Of 102 patients with outflow gradients > or =30 mm Hg at rest, only 43 (42%) had ECG voltage > or =30 mm in any lead. Normal ECG results were uncommonly associated with HC-related death (1 of 40 patients, 2.5%) but had similar prevalence in surviving patients (17 of 376 patients, 4.5%; p = NS). In conclusion, in HC, 12-lead ECG voltages are not a reliable clinical marker for the magnitude of LV hypertrophy or outflow obstruction. Diverse ECG patterns, consistent with heterogeneous expression of this disease, did not predict HC-related death. Scalar electrocardiography has selective but limited power in routine clinical assessments of patients with HC.

Prevalence of hypertrophic cardiomyopathy in a population-based sample of American Indians aged 51 to 77 years (the Strong Heart Study)

Recognition of the frequency with which hypertrophic cardiomyopathy (HC) occurs in the general population is critical to understanding its demographics and public health implications. However, few data are available for estimating HC prevalence in large populations of different age strata and ethnic or racial groups. The Strong Heart Study is a prospective, population-based epidemiologic survey of cardiovascular disease in residents of 13 geographically diverse American Indian communities. The study population was comprised of 3,501 subjects with echocardiograms performed in 1993 and 1995 to determine the prevalence of HC in middle-aged and older adult populations. Evidence of the HC phenotype was present in 8 previously undiagnosed patients (0.23%; 2 of 1,000) based on a left ventricular (LV) wall thickness >/=15 mm and a nondilated cavity that was not associated with another cardiac disease and was sufficient to produce the magnitude of hypertrophy evident. Ages were 51 to 77 years (mean 64 +/- 9). Four subjects were men and 4 were women, with prevalences by gender of 0.3% (3 of 1,000) and 0.18% (1.8 of 1,000), respectively. Maximum LV thicknesses were 19 to 29 mm (mean 21 +/- 3). Two subjects had mitral valve systolic anterior motion, which was sufficient to produce LV outflow obstruction at rest in 1 patient. Different electrocardiographic abnormalities were present in 5 subjects. In conclusion, clinically unrecognized HC was present in 1:500 of an aging American Indian cohort. This prevalence was similar to that reported in other general populations comprised of younger subjects of other races, offering evidence that HC is a relatively common genetic disease with widespread occurrence within the United States.

Preparticipation evaluation: an evidence-based review

OBJECTIVE

To review available evidence establishing the validity of the preparticipation evaluation (PPE) as a method for screening health risk prior to participation in exercise and sport. Specific emphasis was placed on reviewing original research evaluating methods to screen participants for risk of sudden cardiovascular death. Literature on the current state of the PPE as a screening tool for athletic participation was examined.

DATA SOURCES

Electronic databases were searched for articles relating to mass screening for sports participation and sudden cardiac death in athletes published up to January 2004. Databases searched included Medline (OVID Web, 1966-2004), PubMed (1966-2004), Sport Discuss (1975-2004), Current Contents, CISTI Source (1993-2004), Cochrane Database of Systematic Reviews, and EBM Reviews. Additional references from the bibliographies of retrieved articles were also reviewed.

SELECTION CRITERIA

All study designs were retrieved, but only those studying athletes and/or student-athletes under age 36 years were reviewed. Of the original research retrieved, the majority of the articles sought to establish incidence or prevalence of cardiovascular causes of sudden death in athletes or the validity of various screening tools. Original research articles seeking to establish the current use of the PPE in all its various forms were also reviewed. All of the articles selected for review consisted of type II, population-based data.

DATA EXTRACTION AND SYNTHESIS

The initial literature search identified 639 papers. Of these, 310 articles that met the selection criteria were reviewed, and 25 articles were identified as original research directly relating to the PPE. All of these contained type II evidence-population-based clinical studies. The majority of the literature on the PPE consists of type III evidence-case-based opinion papers and position papers from respected authors and sports medicine societies and reports of expert committees. This literature was also reviewed, but only original research relevant to the PPE is reported in this article. The majority of these studies examined cardiovascular diseases and screening procedures.

RESULTS

The 5 studies that assessed the format or effectiveness of the PPE concluded that it was inadequate. The format of the PPE is not standardized and does not consistently address the American Heart Association recommendations for cardiovascular screening history and physical exams. A variety of health care professionals, some without proper training, administer the PPE. The 12 original studies that looked at specific cardiovascular screening techniques were divided on the effectiveness of history, physical examination, electrocardiogram, and echocardiography for detecting cardiovascular risks for sudden death in athletes.

CONCLUSIONS

A PPE is required by most sport organizations in America, but research as to its effectiveness is very limited. PPEs have been mandatory in Italy for many years, and we can draw on some the data recorded over this time. Otherwise, very few studies in America or elsewhere have been performed on the PPE process. The research available indicates that the PPE is not implemented adequately or uniformly. An opportunity exists to create a standardized, validated PPE that meets medical standards for quality and provides sensitive, specific screening of potential participants in sport and exercise.

Family and population strategies for screening and counselling of inherited cardiac arrhythmias

Family screening in inherited cardiac arrhythmias has been performed in The Netherlands since 1996, when diagnostic DNA testing in long QT syndrome (LQTS) and hypertrophic cardiomyopathy (HCM) became technically possible. In multidisciplinary outpatient academic clinics, an adjusted protocol for genetic counselling, originally derived from predictive testing in Huntington's disease, is being used. 1110 individuals, including 842 relatives of index patients, were informed about their risks, and most were tested molecularly and/or clinically for carriership of the disease present in their family. Of 345 relatives who were referred for cardiologic follow-up, 189 are being treated, because of an increased risk of life-threatening arrhythmias. Evaluation of the psychological and social consequences of family screening for inherited arrhythmias can be performed by using the adapted criteria of Wilson and Jüngner, i.e., from a point of view of public health. Preliminary results of psychological research show that parents of children at risk for LQTS show high levels of distress. Many other aspects have to be evaluated yet, making final conclusions about the feasibility of family screening difficult, particularly in HCM. Clinical guidelines are urgently needed. Population screening by molecular testing, for instance in athletic preparticipation screening, will become possible in the future and has its own prerequisites for success.