Overview
The study objective is to identify the earliest changes in energy substrate metabolism in patients with cardiomyopathies (CMP). To achieve this objective, we plan first to test the hypothesis that patients with CMP present focal alterations in myocardial hyperpolarized [1-13C]pyruvate flux.
Description
To measure the regional myocardial [1-13C]lactate to [13C]bicarbonate ratio as an index of mitochondrial oxidation and glycolysis coupling in the heart. Advanced cardiac MRI will be used to characterize cardiac morphology, function, myocardial blood flow and fibrosis.
Heart failure is a major source of morbidity and mortality in the United States. Multiple studies have demonstrated that development of heart failure is related to alteration in cardiac metabolism. Specifically, such changes include a shift from fatty acid oxidation to increased glucose utilization as energy source, with uncoupling of glycolysis and mitochondrial oxidation at the level of the pyruvate dehydrogenase complex. In human subject who were referred for LVAD placement, excised heart muscle samples exhibited significant increase in expression of pyruvate kinase M2 (PKM2) compared to subjects with normal LV function.
Additionally, mechanical unloading decreased PKM2 expression suggesting a correlation between pyruvate utilization and severity of heart failure. Such changes metabolic alterations appear to precede the actual structural changes and might be a possible target for future therapies, although the timeline of such changes remains to be elucidated. Currently, it is unknown whether different types of CMP have different metabolic signatures.
Eligibility
Inclusion Criteria for Control Subjects:
- Subjects who are 18.
- Subjects who have the ability to understand and the willingness to sign a written informed consent.
- While all races and ethnicities will be included, subjects must be able to read and speak the English language. Once the protocol is established, Spanish-speaking participants will be included.
- Women of child-bearing potential must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry, for the duration of study participation. Should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately.
Inclusion Criteria for participants with Cardiomyopathy:
- Subjects who are 18.
- Subjects who have the ability to understand and the willingness to sign a written informed consent.
- While all races and ethnicities will be included, subjects must be able to read and speak the English language. Once the protocol is established, Spanish-speaking participants will be included.
- Women of child-bearing potential must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation. Should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately.
Exclusion criteria:
- Subjects who are receiving any other investigational agents.
- Intercurrent illness including, but not limited to, ongoing or active infection, uncontrolled chronic diseases such as hypertension, lung disease, liver disease, kidney disease, diabetes, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements.
- Subjects who are taking thyroid hormone replacements, have a history of alcohol abuse or illicit drug use.
- Subjects who have contraindication to contrast enhanced MRI examination.
Contraindications to MRI examinations include:
- Medically unstable
- Acute Heart failure
- Severe LVOT obstruction
- Unstable angina
- Child bearing
- Lactating
- Any contraindication per MRI Screening Form including
- Implants contraindicated at 3Tesla, pacemakers
- Implantable Cardioverter Defibrillator (ICD)
- Claustrophobia
- Since each subject is receiving a gadolinium based contrast agent intravenously:
- eGFR ≤ 30 mL/min/1.73m2
- Sickle cell disease
- Hemolytic anemia