PT - JOURNAL ARTICLE AU - Chietsugu Katoh AU - Shinya Kato AU - Tadao Aikawa AU - Masanao Naya AU - Keiichi Magota AU - Osamu Manabe AU - Tohru Shiga TI - Strategy to improve the detectability of Myocardial Flow Reserve in the ischemic myocardial lesion after revascularization using ECG-gated dynamic myocardial PET with 15O-H2O: Comparison with non-gated PET DP - 2019 May 01 TA - Journal of Nuclear Medicine PG - 259--259 VI - 60 IP - supplement 1 4099 - http://jnm.snmjournals.org/content/60/supplement_1/259.short 4100 - http://jnm.snmjournals.org/content/60/supplement_1/259.full SO - J Nucl Med2019 May 01; 60 AB - 259Objectives: To estimate myocardial flow reserve (MFR = stress myocardial blood flow (MBF) / rest MBF) in the ischemic myocardial lesion before and after revascularization with 15O-H2O PET, we developed a method to improve the detectability of MFR using electro-cardiogram (ECG)-gated dynamic myocardial PET with 15O-H2O, which would reduce the left ventricular (LV) wall motion artifact. Estimated MFR from the new method were compared with those from the conventional non-gated dynamic PET. Methods: Thirty patients with ischemic heart disease (68±12 years old, male28, female 2) underwent dynamic 15O-H2O PET during rest and pharmacological (ATP) stress. They all had percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). Before and after the revascularization, the PET study was performed using Philips Gemini TF64, list mode 3D PET data were acquired with ECG signals. For each scan, 500MBq of 15O-H2O was infused slowly for 2 min, dynamic data were acquired for 6 min. Using list mode PET data and ECG signals, both non-gated dynamic images and ECG-gated end-diastolic dynamic images were reconstructed. Coronary arteriograms were also carried out for each patient before and after revascularization, totally 77 ischemic segments with over 50% increase of luminal diameter after revascularization were evaluated. A whole myocardial ROI was positioned and divided into 17 segments. The regional myocardial ROI curve R(t) and left ventricular ROI curve LV(t) were calculated, regional MBF, CFR, perfusable tissue fraction (PTF) and spillover fraction Va in each myocardial ROI were estimated by these curves with single-tissue compartment model analysis with non-linear least squared method as following equations; R(t) = PTF Ct(t) + Va Ca(t), LV(t) = b Ca(t) + (1-b) Ct(t), dCt(t) / dt = MBF Ca(t) - (MBF/p) Ct(t), where Ca(t) and Ct(t) were true arterial and myocardial tissue curves, parameters p and b were partition coefficient in the myocardium and recovery coefficient of the LV ROI counts, respectively. Both non-gated dynamic images and ECG-gated end-diastolic dynamic images were analyzed. Development environment for these analyzing tools were Visual C++ and C#. Results: In the ischemic myocardial segments before revascularization, MFR with ECG-gated PET were estimated significantly lower (1.08±0.29) than those with non-gated PET (1.49±0.64, p<0.001). However, in the ischemic segments after revascularization, MFR from ECG-gated PET yielded significantly higher (1.91±0.56) than those from non-gated PET (1.84±0.57, p<0.05). Then, increase ratio of MFR after revascularization from ECG-gated PET dedicated significantly higher (1.91±0.65) than those from non-gated PET (1.42±0.53, p<0.001). Conclusions: We developed a technique to estimate the myocardial flow reserve in the ischemic myocardial lesion before and after revascularization using ECG-gated dynamic myocardial PET with 15O-H2O. ECG-gated PET enabled to suppress the LV wall motion artifact, and could estimate the increase of the myocardial flow reserve in the ischemic myocardial lesion after revascularization better than conventional non-gated myocardial dynamic PET.