Myocardial Layer-Specific Strain Analysis in Children with Mitochondrial Disease

Area of Science:

• Pediatric Cardiology
• Cardiovascular Imaging
• Mitochondrial Diseases

Background:

• Children with mitochondrial disease (MD) often present with more severe clinical phenotypes than adults.
• Early detection of cardiac involvement, such as cardiomyopathy (CMP), is crucial for managing pediatric MD.
• Conventional and advanced echocardiography can assess cardiac function and detect subtle changes.

Purpose of the Study:

• To assess cardiac function in children with MD using echocardiography.
• To identify unique patterns of cardiac dysfunction in pediatric MD.
• To investigate the development of early cardiomyopathy in children with MD.

Main Methods:

• Retrospective review of medical records for 33 children with MD.
• Transthoracic echocardiography with conventional and advanced myocardial analysis performed on all patients.
• Comparison of echocardiographic data between pediatric MD patients and age-matched healthy controls.

Main Results:

• Children with MD had significantly lower mitral E, E/A, and tissue Doppler E' values, and higher E/E' ratios compared to controls.
• No significant differences in longitudinal and radial strain were observed between groups.
• Circumferential strain was reduced in the endocardium, middle myocardium, and epicardium of children with MD, and correlated with E'.

Conclusions:

• Myocardial circumferential strain may be an early indicator of cardiomyopathy in children with mitochondrial disease.
• Reduced circumferential strain can be detected even when longitudinal and radial strain are preserved.
• This finding suggests a potential early diagnostic marker for predicting CMP in pediatric MD.