Effect of beta-blockers and exercise restriction on the prevention of sudden cardiac death in pediatric hypertrophic cardiomyopathy

BACKGROUND

Risk assessment tools and effective prevention strategies for sudden cardiac death (SCD) in pediatric patients with hypertrophic cardiomyopathy (HCM) have not been established. This study aimed to evaluate the efficacy of beta-blockers and exercise restriction for SCD prevention in this population.

METHODS

We retrospectively reviewed the medical records of patients aged <18 years who were diagnosed with HCM at our center between January 1996 and December 2021. SCD and aborted SCD were defined as SCD equivalents. We divided patients based on whether they were prescribed beta-blockers or exercise restriction and compared the outcomes among the groups. The primary outcome was the overall survival (OS), and the secondary outcome was the cumulative SCD equivalent rate. Outcomes were analyzed using Kaplan-Meier curves and Cox proportional hazard analysis. We also compared patients according to the occurrence of SCD equivalents to identify SCD risk predictors.

RESULTS

Among the 43 included patients [mean age, 7.7 (1.6-12.1) years; 23 male individuals], SCD equivalents occurred in 13 patients over 11.2 (4.5-15.6) years of follow-up, among whom 12 were resuscitated and 1 died. The OS rate was significantly higher in the beta-blocker and exercise restriction groups than in the non-beta-blocker and non-exercise restriction groups (81.3 % vs. 19.1 %, p < 0.01 and 57.4 % vs. 12.7 %, p < 0.01, respectively). Among the 13 patients with SCD equivalents, 5 had 9 recurrent SCD equivalents. A significant difference was observed between the SCD equivalent and non-SCD equivalent groups in the history of suspected arrhythmogenic syncope (p < 0.01) in the univariable but not in the multivariable analysis.

CONCLUSIONS

Beta-blockers and exercise restriction may decrease the risk of SCD in pediatric patients with HCM and should be considered for SCD prevention in this population, particularly because predicting SCD in these patients remains challenging.

Living with Congenital Aortic Stenosis: Exercise Restriction, Patterns of Adherence, and Quality of Life

Modern consensus panel guidelines recommend restriction from most organized sports for patients with moderate or severe aortic stenosis (AS). However, there is little published data on how frequently physicians deviate from guidelines, how well patients adhere to exercise restrictions, or the effect of restriction on patient-reported quality of life. In this study, we surveyed 93 subjects with AS and their cardiologists regarding participation in organized sports, physical activity, weightlifting, and exercise restriction. Subjects completed the pediatric quality of life inventory (PedsQL) and the pediatric cardiac quality of life inventory (PCQLI). We found that subjects with severe AS (n = 3) were commonly, but not universally, restricted from organized sports (n = 2, 66%). Subjects with moderate AS (n = 40) were rarely restricted from organized sports (n = 6, 17%). No physician-specific characteristics were associated with increased likelihood of recommending exercise restriction. Subjects were more likely to be restricted if they were older (16 years vs. 13 years, p 0.02) and had moderate versus mild AS (p 0.013). PCQLI scores for teens and young adults with AS (age 13-25) were lower than a comparison group of patients with mild congenital heart disease. For all age groups, the PedsQL social functioning score was lower for subjects with exercise restriction (p 0.052). In summary, cardiologists apply consensus guidelines leniently when restricting patients with moderate/severe AS from organized sports and weightlifting. Patients with AS routinely adhere to exercise restriction recommendations. Children and young adults with AS and exercise restriction have lower QOL scores in the social functioning domain.

2019 HRS expert consensus statement on evaluation, risk stratification, and management of arrhythmogenic cardiomyopathy: Executive summary

Arrhythmogenic cardiomyopathy (ACM) is an arrhythmogenic disorder of the myocardium not secondary to ischemic, hypertensive, or valvular heart disease. ACM incorporates a broad spectrum of genetic, systemic, infectious, and inflammatory disorders. This designation includes, but is not limited to, arrhythmogenic right/left ventricular cardiomyopathy, cardiac amyloidosis, sarcoidosis, Chagas disease, and left ventricular noncompaction. The ACM phenotype overlaps with other cardiomyopathies, particularly dilated cardiomyopathy with arrhythmia presentation that may be associated with ventricular dilatation and/or impaired systolic function. This expert consensus statement provides the clinician with guidance on evaluation and management of ACM and includes clinically relevant information on genetics and disease mechanisms. PICO questions were utilized to evaluate contemporary evidence and provide clinical guidance related to exercise in arrhythmogenic right ventricular cardiomyopathy. Recommendations were developed and approved by an expert writing group, after a systematic literature search with evidence tables, and discussion of their own clinical experience, to present the current knowledge in the field. Each recommendation is presented using the Class of Recommendation and Level of Evidence system formulated by the American College of Cardiology and the American Heart Association and is accompanied by references and explanatory text to provide essential context. The ongoing recognition of the genetic basis of ACM provides the opportunity to examine the diverse triggers and potential common pathway for the development of disease and arrhythmia.

2019 HRS expert consensus statement on evaluation, risk stratification, and management of arrhythmogenic cardiomyopathy

Arrhythmogenic cardiomyopathy (ACM) is an arrhythmogenic disorder of the myocardium not secondary to ischemic, hypertensive, or valvular heart disease. ACM incorporates a broad spectrum of genetic, systemic, infectious, and inflammatory disorders. This designation includes, but is not limited to, arrhythmogenic right/left ventricular cardiomyopathy, cardiac amyloidosis, sarcoidosis, Chagas disease, and left ventricular noncompaction. The ACM phenotype overlaps with other cardiomyopathies, particularly dilated cardiomyopathy with arrhythmia presentation that may be associated with ventricular dilatation and/or impaired systolic function. This expert consensus statement provides the clinician with guidance on evaluation and management of ACM and includes clinically relevant information on genetics and disease mechanisms. PICO questions were utilized to evaluate contemporary evidence and provide clinical guidance related to exercise in arrhythmogenic right ventricular cardiomyopathy. Recommendations were developed and approved by an expert writing group, after a systematic literature search with evidence tables, and discussion of their own clinical experience, to present the current knowledge in the field. Each recommendation is presented using the Class of Recommendation and Level of Evidence system formulated by the American College of Cardiology and the American Heart Association and is accompanied by references and explanatory text to provide essential context. The ongoing recognition of the genetic basis of ACM provides the opportunity to examine the diverse triggers and potential common pathway for the development of disease and arrhythmia.

Evolving Decisions: Perspectives of Active and Athletic Individuals with Inherited Heart Disease Who Exercise Against Recommendations

Individuals with hypertrophic cardiomyopathy (HCM) and long QT syndrome (LQTS) are advised to avoid certain forms of exercise to reduce their risk of sudden death. Cardiovascular genetic counselors facilitate both adaptation to, and decision-making about, these exercise recommendations. This study describes decision-making and experiences of active adults who exercise above physicians' recommendations. Purposive sampling was used to select adults with HCM and LQTS who self-identified as exercising above recommendations. Semi-structured interviews explored participants' decision-making and the psychological impact of exercise recommendations. Fifteen individuals were interviewed (HCM: 10; LQTS: 5; mean age: 40). Transcripts were coded and analyzed for underlying themes. Despite exercising above recommendations, nearly all participants made some modifications to their prior exercise regimen. Often these decisions changed over time, underscoring the importance of shared decision-making conversations beyond the initial evaluation. The importance of exercise was frequently cited as a reason for continued exercise, as were perceptions of sudden death risk as low, acceptable, or modifiable. Many participants reported that family and friends supported their exercise decisions, with a minority having family or friends that expressed significant reservations. Genetic counselors, cardiologists, and nurses can use these data to inform their counseling regarding exercise recommendations.