“Muscle Bridge” as a Possible Risk Factor for Sudden Cardiac Death in a Child with Hypertrophic Cardiomyopathy: Case Study

Background. Hypertrophic cardiomyopathy (HCM) is one of the most common causes of sudden cardiac death (SCD) in young adults under the age of 35. SCD may be the first and only clinical manifestation of the disease in children. Case presentation. Female patient with HCM and low risk of cardiac events suffered the first episode of SCD associated with physical activity at the age of 12 years 4 months. Acute myocardial ischemia was suspected due to abnormal coronary arteries, “muscle bridge”, that was the trigger of malignant ventricular arrhythmias leading to cardiac arrest. Implantable cardioverter defibrillator (ICD) was installed for secondary SCD prevention. However, the disease has progressed, and the child suffered two more episodes due to ventricular fibrillation, managed by ICD and resuscitation measures. Drug therapy and ICD regimens were adjusted. Myocardial revascularization was not performed due to high surgical risk. Conclusion. Difficulties in management of patient with HCM complicated with acute myocardial ischemia due to congenital coronary arteries anomaly are presented. Myocardial ischemia is not considered as “large” risk factor for SCD in children (according to traditional evaluation). However, it can be a trigger for life-threatening ventricular arrhythmias and negatively affect HCM prognosis as it has been shown in our observation.

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