acipimox and Coronary-Artery-Disease

Currently, with the rapidly increasing number of patients with heart failure due to chronic coronary artery disease, the need for viability studies to guide treatment in these patients is increasing. The most accurate method for viability assessment is metabolic imaging with (18)F-FDG with PET or SPECT. To obtain excellent image quality in all patients, the (18)F-FDG studies should be performed during hyperinsulinemic euglycemic clamping. However, this approach is time-consuming and is not feasible in busy nuclear medicine laboratories. Recently, the use of a nicotinic acid derivative, acipimox, has been suggested, but limited data are available on the image quality of the (18)F-FDG studies using this approach.. We evaluated the feasibility and image quality of (18)F-FDG SPECT (with dual-isotope simultaneous acquisition (DISA) using (99m)Tc-tetrofosmin to assess perfusion) after acipimox administration in 50 nondiabetic patients. The image quality of both (18)F-FDG and (99m)Tc-tetrofosmin was assessed visually and quantitatively using myocardium-to-blood-pool (M/B) ratios as a measure of target-to-background ratio. The image quality and diagnostic value of DISA (99m)Tc-tetrofosmin SPECT was compared with standard (99m)Tc-tetrofosmin SPECT at baseline.. After acipimox administration, the plasma levels of free fatty acids were extremely low (68 +/- 89 nmol/L). No severe side effects were observed, only paroxysmal flushing. The (18)F-FDG image quality was good in 46 patients (92%) and moderate but still interpretable in the other 4 patients (8%). The clinical information of the baseline (99m)Tc-tetrofosmin SPECT was retained in the DISA (99m)Tc-tetrofosmin SPECT images because we did observe no substantial fill-in of perfusion defects by high (18)F-FDG uptake in the same segment.. Cardiac (18)F-FDG SPECT after acipimox is safe and resulted consistently in good image quality; this simple approach may be the method of choice for routine cardiac metabolic imaging.

Topics: Administration, Oral; Chronic Disease; Coronary Artery Disease; Echocardiography; Feasibility Studies; Female; Fluorodeoxyglucose F18; Heart; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Pyrazines; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

During the noninvasive assessment of myocardial viability with (18)F-FDG metabolic imaging, adequate regulation of metabolic conditions is needed to ensure optimal image quality. The aim of this study was to compare the feasibility and image quality of cardiac (18)F-FDG SPECT imaging using acipimox in patients with diabetes and patients without diabetes.. Seventy patients with ischemic cardiomyopathy underwent (18)F-FDG SPECT using acipimox for the assessment of myocardial viability, followed by resting 2-dimensional echocardiography to identify dysfunctional myocardial tissue. The image quality was scored visually and quantitatively; the myocardium-to-background ratio was determined by region-of-interest analysis. The plasma concentrations of glucose and free fatty acids were determined to evaluate the metabolic conditions before and during (18)F-FDG imaging.. Thirty-four patients had diabetes mellitus; of these, 12 had insulin-dependent diabetes mellitus and 22 had non-insulin-dependent diabetes mellitus. The remaining 36 patients had no diabetes. During (18)F-FDG SPECT, no severe side effects occurred. Acipimox significantly lowered plasma levels of free fatty acids in both groups. Fifteen of 34 patients with diabetes had a plasma glucose level > 9 mmol/L, which was lowered successfully in all patients with additional insulin. Visual evaluation of the (18)F-FDG images showed good, moderate, and poor image quality in 27, 5, and 2 patients, respectively, with diabetes mellitus and in 32, 4, and 0 patients, respectively, without diabetes (P = not statistically significant). The myocardium-to-background ratio of (18)F-FDG SPECT images was comparable in patients with and without diabetes mellitus (3.1 +/- 1.0 vs. 3.5 +/- 0.9, P = not statistically significant). The type of diabetes had no influence on (18)F-FDG image quality.. (18)F-FDG SPECT metabolic imaging after acipimox is safe and practical for routine assessment of viability in patients with ischemic cardiomyopathy. Image quality is good, even in patients with diabetes, although additional insulin is sometimes needed.

Topics: Blood Glucose; Coronary Artery Disease; Diabetes Complications; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Fatty Acids, Nonesterified; Feasibility Studies; Female; Fluorodeoxyglucose F18; Heart Ventricles; Humans; Male; Middle Aged; Pyrazines; Radionuclide Imaging; Radiopharmaceuticals; Ventricular Dysfunction, Left