Identification of Carnitine-Responsive Cardiomyopathy
Identification of Carnitine-Responsive Cardiomyopathy
There are some adults with skeletal muscle weakness (called "myopathy") and heart muscle
 weakness (called "cardiomyopathy") who have low blood levels of a compound called carnitine
 as a cause of their problems. Carnitine is very important to energy production in muscles. In
 fact, there are reports of some people with carnitine deficiency who have developed myopathy
 and cardiomyopathy that was completely reversed with carnitine treatment. The main objective
 of our project is to determine the number of patients who have carnitine deficiency as a
 cause of their myopathy and cardiomyopathy. The investigators will be measuring carnitine
 levels in 1000 patients with cardiomyopathy and will describe the specific features in all
 the study patients to see if there are any trends that may help us predict which patients
 with muscle weakness are at risk of developing low carnitine levels. The investigators will
 be treating patients with low carnitine levels with carnitine and observing them to see if
 their cardiomyopathy and their muscle weakness improve. Knowing the exact percentage of
 myopathy and cardiomyopathy patients with carnitine deficiency may allow for screening of
 patients in a cheap and targeted way to treat the serious complication of this condition,
 including heart failure and sudden death.
The primary objective of this research is to determine the prevalence of primary and
 secondary (genetic and acquired) carnitine deficiency in patients with limb girdle weakness
 and hypertrophic or idiopathic dilated cardiomyopathy where an underlying cause is unknown.
 Identification and treatment with carnitine may potentially reverse or halt heart failure and
 skeletal muscle weakness in these patients.

 Specific aims:

 1. To ascertain the prevalence of primary and secondary carnitine deficiency in a
 population of adults with myopathy and hypertrophic and dilated cardiomyopathy of
 unknown etiology

 2. To describe the demographic and phenotypic characteristics of patients with myopathy and
 dilated or hypertrophic cardiomyopathy who have primary and secondary carnitine
 deficiency

 3. To measure the motor and cardiovascular response to carnitine supplementation in
 patients with myopathy, cardiomyopathy and carnitine deficiency
Inclusion Criteria:

 -  An adult patient (>18 years) with a diagnosis of either hypertrophic or dilated
 cardiomyopathy, for which the underlying etiology of the cardiomyopathy is unknown.

 Exclusion Criteria:

 -  A history of ischemia

 -  A documented or suspected infection including HIV

 -  A history of severe longstanding hypertension

 -  A history of valvular heart disease

 -  A history of chemotherapy exposure

 -  A history of alcohol abuse

 -  Carnitine supplementation at the time of recruitment