Clinical characteristics and outcomes in childhood-onset hypertrophic cardiomyopathy.

2021

2021 Mar 26

1522-9645

<p><strong>AIMS: </strong>Childhood-onset hypertrophic cardiomyopathy (HCM) is far less common than adult-onset disease, thus natural history is not well characterized. We aim to describe the characteristics and outcomes of childhood-onset HCM.</p>

<p><strong>METHODS AND RESULTS: </strong>We performed an observational cohort study of 7677 HCM patients from the Sarcomeric Human Cardiomyopathy Registry (SHaRe). Hypertrophic cardiomyopathy patients were stratified by age at diagnosis [&lt;1 year (infancy), 1-18 years (childhood), &gt;18 years (adulthood)] and assessed for composite endpoints reflecting heart failure (HF), life-threatening ventricular arrhythmias, atrial fibrillation (AF), and an overall composite that also included stroke and death. Stratifying by age of diagnosis, 184 (2.4%) patients were diagnosed in infancy; 1128 (14.7%) in childhood; and 6365 (82.9%) in adulthood. Childhood-onset HCM patients had an ∼2%/year event rate for the overall composite endpoint, with ventricular arrhythmias representing the most common event in the 1st decade following baseline visit, but HF and AF becoming more common by the end of the 2nd decade. Sarcomeric variants were more common in childhood-onset HCM (63%) and carried a worse prognosis than non-sarcomeric disease, including a greater than two-fold increased risk of HF [HRadj 2.39 (1.36-4.20), P = 0.003] and 67% increased risk of the overall composite outcome [HRadj 1.67 (1.16-2.41), P = 0.006]. When compared with adult-onset HCM, childhood-onset was 36% more likely to develop life-threatening ventricular arrhythmias [HRadj 1.36 (1.03-1.80)] and twice as likely to require transplant or ventricular assist device [HRadj 1.99 (1.23-3.23)].</p>

<p><strong>CONCLUSION: </strong>Patients with childhood-onset HCM are more likely to have sarcomeric disease, carry a higher risk of life-threatening ventricular arrythmias, and have greater need for advanced HF therapies. These findings provide insight into the natural history of disease and can help inform clinical risk stratification.</p>

10.1093/eurheartj/ehab148

Eur Heart J

33769460

Associations Between Female Sex, Sarcomere Variants and Clinical Outcomes in Hypertrophic Cardiomyopathy.

2020

2020 Dec 07

2574-8300

<p><strong>Background&nbsp;</strong>- The impact of sex on phenotypic expression in hypertrophic cardiomyopathy (HCM) has not been well characterized in genotyped cohorts. <strong>Methods&nbsp;</strong>- Retrospective cohort study from an international registry of patients receiving care at experienced HCM centers. Sex-based differences in baseline characteristics and clinical outcomes were assessed. <strong>Results&nbsp;</strong>- Of 5,873 patients (3,788 genotyped), 2,226 (37.9%) were women. At baseline, women were older (49.0±19.9 vs. 42.9±18.4 years, p&lt;0.001) and more likely to have pathogenic/likely-pathogenic sarcomeric variants (SARC+; 51% vs 43%, p&lt;0.001) despite equivalent utilization of genetic testing. Age at diagnosis varied by sex and genotype despite similar distribution of causal genes. Women were 3.6 to 7.1 years older at diagnosis (p&lt;0.02) except for patients with variants where age at diagnosis was comparable for women and men (n=492; 34.8±19.2 vs 33.3±16.8 years, p=0.39). Over 7.7 median years of follow up, NYHA III-IV heart failure (HF) was more common in women (HR 1.87, CI 1.48-2.36, p&lt;0.001), after controlling for their higher burden of symptoms and outflow tract obstruction at baseline, reduced ejection fraction, SARC+, age and hypertension. All-cause mortality was increased in women (HR 1.50, CI 1.13-1.99, p&lt;0.01), but neither ICD utilization nor ventricular arrhythmia varied by sex. <strong>Conclusions&nbsp;</strong>- In HCM, women are older at diagnosis, partly modified by genetic substrate. Regardless of genotype, women were at higher risk of mortality and developing severe HF symptoms. This points to a sex-effect on long-term myocardial performance in HCM, which should be investigated further.</p>

10.1161/CIRCGEN.120.003062

Circ Genom Precis Med

33284039