Osamu Manabe

Focus Issue on Cardiac Sarcoidosis from International Congress of Nuclear Cardiology and Cardiac CT (ICNC 12) Symposium: Improving the Detectability of Cardiac Sarcoidosis—Practical Aspects of 18 F-fluorodeoxyglucose Positron Emission Tomography Imaging for Diagnosis of Cardiac Sarcoidosis—

Cardiac sarcoidosis(CS)increases the risk of cardiovascular event such as conduction abnormalities, ventricular arrhythmia and heart failure in patients with sarcoidosis. Recently the Heart Rhythm Society(HRS)issued a consensus on the detection of CS. In this report, 18 F-fluorodeoxyglucose ( 18 F- FDG)positron emission tomography(PET)is employed in the diagnosis of CS. In 2012, the Japanese Ministry of Health, Labor, and Welfare(JMHLW)approved cardiac 18 F-FDG PET for the detection

Feasibility of Quantifying Myocardial Blood Flow with a Shorter Acquisition Time Using 15 O-H 2 O PET

Purpose: The quantification of coronary flow reserve (CFR) calculated as the ratio of the myocardial blood flow (MBF) during adenosine triphosphate (ATP) stress to MBF at rest is a useful method for evaluating the functional severity of coronary artery disease (CAD) using 15 O-H2O positron emission tomography (PET). The shorter acquisition time may reduce dyspnea and other side effects of ATP stress and may also reduce the effect of body movements during data acquisition. However, the impact of the shorter data acquisition time on the accuracy of MBF quantification has not been studied. In this retrospective study, we evaluated the accuracy of the MBF and CFR values obtained with shorter scan times using 15 O-H2O PET. Methods: Thirty patients suspected of having CAD (22 males, 8 females; age 56.5±8.8 yrs) and 17 healthy controls (17 males; age 27.7±6.2 yrs) underwent PET during rest and PET with ATP stress dynamic 15 O-H2O. The MBF was estimated with a one-tissue compartment model analysis. MBF and CFR values were calculated using the first 2-min and 3-min PET data of 15 O-H2O as shorter data acquisitions. These data were compared to the standard 6-min PET acquisition data. Results: With the use of the 3-min data, the regions of interest (ROIs) in the left ventricular (LV) chamber and myocardium could be set for all of the subjects. The intraclass correlation coefficients (ICCs) between the 3-min data and 6-min data of the rest MBF, stress MBF and CFR were 0.869, 0.870, and 0.819 in the patients, and 0.912, 0.910, and 0.930 in the controls. The 3-min CFR data showed a significant difference between the patients and controls (2.22±1.02 vs. 4.02±1.50, p<0.01), as did the 6-min data (2.19±0.92 vs. 4.16±1.39, p<0.01). However, the CFR based on 2-min data did not show a significant difference (1.96±1.66 vs. 2.73±1.03, p=0.088). Using a receiver operating characteristic (ROC) analysis, we observed that both the 3-min and 6-min CFR data could be used to separate the CAD patients and controls. Conclusions: A 3-min, but not 2-min, scan with 15 O-H2O PET can be used for the quantitative evaluation of MBF and CFR.