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Published on: August 8, 2022
Thirty-year outcome in children with hypertrophic cardiomyopathy based on the type
Etsuko Tsuda1, Yuki Ito1, Yoshiaki Kato1
1Department of Pediatric Cardiology, National Cerebral and Cardiovascular Center, Osaka, Japan.
Insights
Long-term outcomes for children with hypertrophic cardiomyopathy (HCM) are poor, especially for secondary HCM (s-HCM). The development of a dilated phase significantly worsens prognosis, with sudden death often occurring around age 15.
Area of Science:
- Pediatric Cardiology
- Genetics
- Cardiovascular Research
Background:
- Hypertrophic cardiomyopathy (HCM) is a significant cause of pediatric heart disease.
- Understanding the long-term outcomes of different HCM subtypes in children is crucial for prognosis and management.
Approach:
- Retrospective review of medical records for 100 pediatric HCM patients (1977-2015).
- Kaplan-Meier method used to calculate survival and cardiac event-free survival rates.
- Analysis stratified by HCM type: Noonan syndrome, hypertrophic obstructive cardiomyopathy (HOCM), idiopathic HCM (i-HCM), and secondary HCM (s-HCM).
Key Points:
- Secondary HCM (s-HCM) showed a very poor 20-year survival rate of 17%.
- A dilated phase of HCM occurred in 24 patients, with 79% dying of heart failure.
- Sudden death and implantable cardioverter-defibrillator (ICD) implantation were common around age 15.
Conclusions:
- Long-term outcomes for pediatric HCM patients are generally poor, with s-HCM having the worst prognosis.
- The development of a dilated phase is a critical negative prognostic indicator in pediatric HCM.
- HCM management strategies should consider the high risk of adverse events, including sudden death, around adolescence.
Background:
We reviewed the long-term outcome of children with hypertrophic cardiomyopathy (HCM) based on the type.
Methods:
We reviewed the medical records of 100 patients (male 54 female 46) with HCM at our hospital between 1977 and 2015. The survival and cardiac event-free survival rates were calculated by the Kaplan-Meier method.
Results:
The age at the time of the diagnosis ranged from 0 to 15 years with a median of 8 years. The number of patients with Noonan syndrome and hypertrophic obstructive cardiomyopathy (HOCM), idiopathic HCM (i-HCM), and secondary HCM (s-HCM) was 13, 13, 65, and 9 respectively. A dilated phase of HCM occurred in 24 patients. Nineteen (79 %) of the 24 patients died of heart failure, and two underwent a heart transplantation. Eight (33 %) of the 24 patients had s-HCM. The median age when a dilated phase occurred was 15 years old, and the median interval from the initial diagnosis to the dilated phase was 8 years. The median time from the diagnosis of a dilated phase to death was 1.6 years. Sudden death and implantable cardioverter defibrillator implantations occurred in 6 and 11 patients at around 15 years old, respectively. The 20-year survival rates were as follows: Noonan syndrome 84 %; HOCM 82 %; i-HCM 71 %; and s-HCM 17 %. Overall, the survival rates at 10, 20, and 30 years were 83 % (95 % confidence interval 73-89), 69 % (58-78), and 63 % (50-74), respectively. The overall cardiac event-free survival rates at 10, 20, and 30 years were 57 % (47-67), 39 % (31-50), and 32 % (21-44), respectively.
Conclusion:
The long-term outcome in children with HCM was poor, and the outcome of s-HCM was very poor. The occurrence of a dilated phase worsened the outcome in HCM patients. Sudden death and d-HCM often occurred at around 15 years old.
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