Association of Insulin Resistance and FGF21 on Cardiac Function in Pediatric Dilated Cardiomyopathy

This study will investigate whether there is an association between insulin resistance and cardiac function in children with dilated or hypertrophic cardiomyopathy. This study will also investigate whether there is an association between FGF21 and cardiac function in children with dilated or hypertrophic cardiomyopathy and whether this is mediated through greater insulin resistance and/or through independent effects.

Although pediatric cardiomyopathy is rare, the condition is severe and life-threatening. The main focus of this proposed study will examine whether insulin resistance is correlated with decreased cardiac function which will hopefully pave the way for future clinical trials using medications that sensitize insulin such as metformin or glucagon-like peptide-1 (GLP-1 agonists) as possible therapeutic agents. The exploratory piece of this study will investigate a novel therapeutic target by determining whether FGF21 has any direct effects on cardiac function and whether it interacts with insulin resistance in altering cardiac function. Patients with cardiomyopathy normally undergo ECHO as part of routine evaluation and follow up and is standard of care. At this time, there are no official guidelines for pediatric patients with cardiomyopathy to undergo oral glucose tolerance testing (OGTT) and thus it is not part of the standard of care. Based on findings from this study, the investigators hope to justify performing an OGTT on pediatric patients with dilated or hypertrophic cardiomyopathy and incorporate the procedure in future practice guidelines.

only one arm, all participants undergo oral glucose tolerance testing and results are used to evaluate association with degree of cardiac dysfunction

Inclusion Criteria: Diagnosis of dilated or hypertrophic cardiomyopathy Pubertal (Tanner 2 breast in females or testicular volume ≥ 4mL in males) Permission by the primary cardiologist of the patient for enrollment in the study Exclusion Criteria: Prior diagnosis of diabetes and treatment with anti-diabetes medication Neuromuscular disorder Inborn error of metabolism Malformation syndrome Clinically unstable based on the assessment of the primary cardiologist caring for the patient inability of parent/legal guardian to provide informed consent non-English speaking

This is a single center, pilot study; data will not be made available but findings from the study will be published

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