Pediatric viral myocarditis: mechanisms, experimental models, and research gaps

Area of Science:

• Pediatric cardiology
• Immunology
• Virology

Background:

• Viral myocarditis is a significant cause of pediatric cardiac inflammation, dilated cardiomyopathy, and sudden cardiac death.
• Current mechanistic understanding largely stems from adult models, creating a knowledge gap in pediatric disease pathogenesis.
• Age-specific differences in immune responses, viral tropism, and clinical outcomes are critical but understudied in children.

Purpose of the Study:

• To review viral pathogens implicated in pediatric myocarditis and their roles in acute and chronic cardiac injury.
• To analyze experimental models of pediatric viral myocarditis, considering factors influencing disease severity and translational relevance.
• To highlight age-specific vulnerabilities, cellular/molecular mechanisms of myocardial damage, and progression to dilated cardiomyopathy.

Main Methods:

• Literature review focusing on viral myocarditis in pediatric populations.
• Analysis of experimental infection models, including viral species, host strain, and administration route.
• Examination of cellular and molecular mechanisms of cardiac injury and disease progression.

Main Results:

• Pediatric viral myocarditis exhibits distinct immune responses, viral tropism, and clinical outcomes compared to adults.
• Experimental models reveal pediatric immune system vulnerabilities, altered viral persistence, and specific mechanisms of myocardial damage.
• Differences in heart anatomy and physiology between murine models and humans limit translational relevance.

Conclusions:

• Pediatric viral myocarditis requires dedicated research models that account for developmental differences in immunity and viral interactions.
• Understanding age-specific mechanisms is essential for developing targeted therapies to reduce morbidity and mortality in children.
• Future research should prioritize the development and validation of pediatric-specific models to advance diagnosis and treatment strategies.