Left Ventricular Systolic Dysfunction in Patients Diagnosed With Hypertrophic Cardiomyopathy During Childhood: Insights From the SHaRe Registry (Sarcomeric Human Cardiomyopathy).

2023

05/2023

1524-4539

BACKGROUND: The development of left ventricular systolic dysfunction (LVSD) in hypertrophic cardiomyopathy (HCM) is rare but serious and associated with poor outcomes in adults. Little is known about the prevalence, predictors, and prognosis of LVSD in patients diagnosed with HCM as children.

METHODS: Data from patients with HCM in the international, multicenter SHaRe Registry (Sarcomeric Human Cardiomyopathy) were analyzed. LVSD was defined as left ventricular ejection fraction <50% on echocardiographic reports. Prognosis was assessed by a composite of death, cardiac transplantation, and left ventricular assist device implantation. Predictors of developing incident LVSD and subsequent prognosis with LVSD were assessed using Cox proportional hazards models.

RESULTS: We studied 1010 patients diagnosed with HCM during childhood (<18 years of age) and compared them with 6741 patients with HCM diagnosed as adults. In the pediatric HCM cohort, median age at HCM diagnosis was 12.7 years (interquartile range, 8.0-15.3), and 393 (36%) patients were female. At initial SHaRe Registry site evaluation, 56 (5.5%) patients with childhood-diagnosed HCM had prevalent LVSD, and 92 (9.1%) developed incident LVSD during a median follow-up of 5.5 years. Overall LVSD prevalence was 14.7% compared with 8.7% in patients with adult-diagnosed HCM. Median age at incident LVSD was 32.6 years (interquartile range, 21.3-41.6) for the pediatric cohort and 57.2 years (interquartile range, 47.3-66.5) for the adult cohort. Predictors of developing incident LVSD in childhood-diagnosed HCM included age <12 years at HCM diagnosis (hazard ratio [HR], 1.72 [CI, 1.13-2.62), male sex (HR, 3.1 [CI, 1.88-5.2), carrying a pathogenic sarcomere variant (HR, 2.19 [CI, 1.08-4.4]), previous septal reduction therapy (HR, 2.34 [CI, 1.42-3.9]), and lower initial left ventricular ejection fraction (HR, 1.53 [CI, 1.38-1.69] per 5% decrease). Forty percent of patients with LVSD and HCM diagnosed during childhood met the composite outcome, with higher rates in female participants (HR, 2.60 [CI, 1.41-4.78]) and patients with a left ventricular ejection fraction <35% (HR, 3.76 [2.16-6.52]).

CONCLUSIONS: Patients with childhood-diagnosed HCM have a significantly higher lifetime risk of developing LVSD, and LVSD emerges earlier than for patients with adult-diagnosed HCM. Regardless of age at diagnosis with HCM or LVSD, the prognosis with LVSD is poor, warranting careful surveillance for LVSD, especially as children with HCM transition to adult care.

10.1161/CIRCULATIONAHA.122.062517

Circulation

37226762

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