title: Imaging of metabolism and autonomic innervation of the heart by positron emission tomography.
abstract: Positron emission tomography (PET) allows, in combination with multiple radiopharmaceuticals, unique physiological and biochemical tissue characterization. Tracers of blood flow, metabolism and neuronal function have been employed with this technique for research application. More recently, PET has emerged in cardiology as a useful tool for the detection of coronary artery disease and the evaluation of tissue viability. Metabolic tracers such as fluorine-18 deoxyglucose (FDG) permit the specific delineation of ischaemically compromised myocardium. Clinical studies have indicated that the metabolic imaging is helpful in selecting patients for coronary artery bypass surgery or coronary angioplasty. More recent research work has concentrated on the use of carbon-11 acetate as a marker of myocardial oxygen consumption. Together with measurements of left ventricular performance, estimates of cardiac efficiency can be derived from dynamic 11C-acetate studies. The non-invasive evaluation of the autonomic nervous system of the heart was limited in the past. With the introduction of radiopharmaceuticals which specifically bind to neuronal structures, the regional integrity of the autonomic nervous system of the heart can be evaluated with PET. Numerous tracers for pre- and postsynaptic binding sites have been synthesized. 11C-hydroxyephedrine represents a new catecholamine analogue which is stored in cardiac presynaptic sympathetic nerve terminals. Initial clinical studies with it suggest a promising role for PET in the study of the sympathetic nervous system in various cardiac diseases such as cardiomyopathy, ischaemic heart disease and diabetes mellitus. The specificity of the radio-pharmaceuticals and the quantitative measurements of tissue tracer distribution provided by PET make this technology a very attractive research tool in the cardiovascular sciences with great promise in the area of cardiac metabolism and neurocardiology.
authors.affiliation: Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109-0028.
authors.forename: P
authors.initials: P
authors.lastname: Mélon
authors.forename: M
authors.initials: M
authors.lastname: Schwaiger
mesh_terms: D001341:Autonomic Nervous System / Q000000981:diagnostic imaging*; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging; D003327:Coronary Disease / Q000000981:diagnostic imaging; D006321:Heart / Q000000981:diagnostic imaging* / Q000294:innervation; D006801:Humans; D009203:Myocardial Infarction / Q000000981:diagnostic imaging; D009206:Myocardium / Q000378:metabolism; D011849:Radioactive Tracers; D014055:Tomography, Emission-Computed
chemical_list: D011849:Radioactive Tracers