Clinical Report: Severe Cardiac Dysfunction Induced by Dual Factors in a Pediatric Patient

Overview

This report details a case of a 5-year-old boy with dilated cardiomyopathy (DCM) caused by a homozygous CAP2 mutation, triggered by a respiratory viral infection. The findings highlight the interaction between genetic predisposition and environmental factors in pediatric cardiac dysfunction.

Background

Dilated cardiomyopathy (DCM) is a significant cause of heart failure in children, often linked to genetic mutations. Understanding the role of viral infections as triggers in genetically predisposed individuals is crucial for early diagnosis and management. This case emphasizes the need for genetic screening in pediatric patients presenting with unexplained cardiac issues.

Data Highlights

The proband was a 5-year-old boy with a homozygous CAP2 variant (c.551G > A; p.W184*), presenting with fulminant cardiac dysfunction after a positive rhinovirus test.

Key Findings

• The patient exhibited a novel homozygous CAP2 mutation leading to severe cardiac dysfunction.
• Respiratory viral infection was identified as a triggering factor for the patient's condition.
• Intensive therapies were effective in reversing ventricular remodeling.
• The case illustrates a 'double-hit' pathogenic mechanism involving genetic susceptibility and viral insult.
• Early genetic screening is recommended for children with unexplained cardiac malformations.

Clinical Implications

Healthcare providers should prioritize genetic evaluation in pediatric patients with unexplained cardiac symptoms. Infection prevention and adherence to vaccination schedules are critical for patients with known genetic predispositions to DCM.

Conclusion

This case underscores the importance of recognizing the interplay between genetic factors and environmental triggers in pediatric cardiomyopathy. Early intervention and genetic screening can significantly impact patient outcomes.

Related Resources & Content

1. Frontiers in Cardiovascular Medicine, 2026 -- Novel compound heterozygous mutations in KLHL24-induced recessive inherited hypertrophic cardiomyopathy: a case report
2. Pediatric Cardiology, 2017 -- Identification of New Genetic Variants in BAG3 and TNNT2 in a Swedish Family with a Background of Dilated Cardiomyopathy and Sudden Cardiac Events
3. Integration of genetic testing into diagnostic pathways for cardiomyopathies: a clinical consensus statement by the ESC Council on Cardiovascular Genomics | European Heart Journal | Oxford Academic
4. Frontiers | Genotype-phenotype insights of pediatric dilated cardiomyopathy
5. Pediatric Cardiology — Pulmonary Interstitial Glycogenosis: A Potential Overlooked Cause of Persistent Pulmonary Hypertension in Newborns with Congenital Heart Defects?
6. Pediatric Cardiology — Asymptomatic ALCAPA with Maintained Cardiac Function in a 3-Year-Old Patient
7. 2024 ACC Expert Consensus Decision Pathway on Strategies and Criteria for the Diagnosis and Management of Myocarditis
8. Integration of genetic testing into diagnostic pathways for cardiomyopathies: a clinical consensus statement by the ESC Council on Cardiovascular Genomics | European Heart Journal | Oxford Academic
9. Frontiers | Genotype-phenotype insights of pediatric dilated cardiomyopathy
10. Imaging based risk factors for heart failure death in childhood dilated cardiomyopathy: a systematic review and meta-analysis - PubMed
11. Illuminating a Hidden Risk: The Genetic Contribution to Acute Myocarditis∗ | JACC: Heart Failure
12. Part 8: Pediatric Advanced Life Support: 2025 American Heart Association and American Academy of Pediatrics Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care | Pediatrics | American Academy of Pediatrics
13. Frontiers | "Double-Hit" Precipitates Fulminant Cardiac Dysfunction in a Child with Homozygous CAP2 Variant: A Case Report
14. A homozygous CAP2 pathogenic variant in a neonate presenting with rapidly progressive cardiomyopathy and nemaline rods - PubMed