Myocardial metabolic imaging: Viability and beyond

Abstract

Because of the high metabolic cost of maintaining an adequate cardiac output, the heart possesses the ability to utilize a wide variety of metabolic substrates, including fatty acids, glucose, lactate, amino acids, and ketone bodies. The relative contribution of each of these substrates is regulated by multiple factors, including substrate concentration, presence of adequate blood flow and oxygen, the action of a variety of hormones, and the influences of disease states that can alter the metabolic machinery of the heart. This review summarizes the biochemical and cellular basis of myocardial substrate selection, as well as the changes in the metabolic phenotype of the heart in response to cardiac diseases. Based on this background, this review also illustrates the nuclear-based imaging techniques that can be used to assess myocardial metabolism and their current and future applications to patient care.