Predictors of Long-Term Outcome in Children with Hypertrophic Cardiomyopathy

Area of Science:

• Cardiology
• Pediatric Cardiology
• Genetics

Background:

• Hypertrophic cardiomyopathy (HCM) in children has limited data on predicting progression to end-stage heart failure (HF) or sudden cardiac death (SCD).
• Understanding long-term outcomes and risk factors is essential for timely intervention and management in pediatric HCM patients.

Purpose of the Study:

• To identify predictors of major adverse cardiovascular events in children diagnosed with HCM.
• To differentiate risk factors for arrhythmic events versus heart failure progression in this cohort.

Main Methods:

• A cohort of 112 children with HCM (median age 14.1 years) was followed for a median of 6.5 years.
• Outcomes assessed included a composite primary end point, secondary arrhythmic end points (cardiac arrest, ICD discharge, SCD), and secondary HF end points (HF death, transplant).
• Multivariate analysis was used to determine independent predictors for each outcome category.

Main Results:

• Overall, 21% of patients reached the composite primary end point, with a 10-year event-free survival rate of 76%.
• Independent predictors for arrhythmic events included prior cardiac arrest, QTc dispersion, and non-sustained ventricular tachycardia (NSVT).
• Independent predictors for HF events included left atrial (LA) size, left ventricular (LV) posterior wall thickness, and decreased early transmitral flow velocity.

Conclusions:

• Risk factors for SCD and HF-related death differ significantly in pediatric HCM.
• Prior cardiac arrest, QTc dispersion, and NSVT are key predictors of arrhythmic events in children with HCM.
• LA size, LV posterior wall thickness, and impaired diastolic function predict HF progression in pediatric HCM.