Primary carnitine deficiency cardiomyopathy International Journal of Cardiology Carnitine Deficiency: What Is It, Causes, Symptoms, and More Osmosis Cardiac Energy Metabolism in Heart Failure Circulation Research TMAO: how gut microbiota contributes to heart failure Translational Research L carnitine is primarily synthesized in the liver from the amino acids lysine and methionine through a series of four enzymatic reactions, with the liver and kidneys converting the precursor butyrobetaine into active