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Conduction abnormalities in pediatric patients with restrictive cardiomyopathy.
Mark A Walsh1, Michelle A Grenier, John L Jefferies
1Heart Institute, Division of Pediatric Cardiology, Cincinnati Children's Hospital; Medical Center, Cincinnati, OH 45229, USA.
Circulation. Heart Failure
|January 21, 2012
Summary
Pediatric restrictive cardiomyopathy patients face sudden death risks from heart block, not just arrhythmias. Early ECG monitoring and defibrillator/pacemaker implantation are crucial for managing these conduction abnormalities.
Area of Science:
- Cardiology
- Pediatric Electrophysiology
Background:
- Pediatric restrictive cardiomyopathy has a poor prognosis with high sudden death risk.
- Sudden death was previously attributed to ventricular tachyarrhythmias.
- Conduction abnormalities and their link to life-threatening events in this population were unreported.
Purpose of the Study:
- To investigate the extent of conduction abnormalities in pediatric restrictive cardiomyopathy.
- To determine the relationship between conduction abnormalities and life-threatening events.
- To identify risk factors for sudden cardiac events in pediatric restrictive cardiomyopathy.
Main Methods:
- Retrospective study of pediatric patients with restrictive cardiomyopathy (April 1994 - May 2011).
- Evaluation of demographic, cardiac, and ECG characteristics.
- Analysis of serious arrhythmic events, including death and hemodynamic compromise.
Main Results:
- Five sudden cardiac events (4 deaths) occurred in 16 patients.
- Two deaths resulted from acute heart block; one patient with syncope had intermittent heart block.
- Longer PR interval and QRS duration were significantly associated with acute cardiac events.
- Older age at presentation correlated with sudden cardiac events.
Conclusions:
- Pediatric restrictive cardiomyopathy patients are at risk for high-grade heart block and bradycardic events.
- Aggressive ECG monitoring for conduction system disease is recommended.
- Prophylactic defibrillator/pacemaker implantation should be considered.
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