Myocardial Fatty Acid Metabolism

Abstract

The expression of myocardial fatty acid β-oxidation enzymes is downregulated at the gene transcriptional level in animal models of left ventricular hypertrophy and of heart failure. Humans with idiopathic dilated cardiomyopathy have decreased myocardial fatty acid oxidation. The extent to which molecular mechanisms, such as a reduction in myocardial fatty acid oxidation, regulate the cardiac hypertrophic response in humans in vivo is unknown. Positron emission tomography was used to measure myocardial blood flow, oxygen consumption, fatty acid utilization, and oxidation in two groups of patients: (1) hypertensive left ventricular hypertrophy (n=19; left ventricular mass, 211±39 g; left ventricular ejection fraction, 67±4%) and (2) left ventricular dysfunction (n=9; left ventricular mass, 210±36 g; left ventricular ejection fraction, 31±10%); these were compared with a normal control group (n=36; left ventricular mass, 139±25 g; left ventricular ejection fraction, 66±6%). Left ventricular mass showed signi...