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Background: Myocardial blood flow (MBF) quantitation with cadmium-zinc-telluride (CZT) dynamic single-photon emission computed tomography (SPECT) is being increasingly investigated toward clinical utilization.Methods: In this prospective study, forty-nine patients with suspected or known coronary artery disease (CAD) underwent a rest/adenosine triphosphate (ATP) stress dynamic and routine gated myocardial perfusion imaging (MPI) by CZT SPECT and then received coronary angiography (CAG). Quantitative diagnosis from the dynamic SPECT and a flow diagram was automatically obtained by the dedicated software and compared with the result of semi-quantitative analysis with gated MPI using the angiographic stenosis as the reference standard.Results: When stenosis ≥50% was considered at the participant level, the sensitivity (SN), specificity (SP), positive predictive value (PPV), negative predictive value (NPV) and accuracy (AC) of the quantitative diagnosis were higher than semi-quantitative method as (84.4% vs. 65.6%, 88.2% vs. 70.6%, 93.1% vs. 80.8%, 75.0% vs. 52.2%, 85.7% vs. 67.3%) (all P<0.05). The receiver operating characteristic (ROC) curve analysis generated the optimal critical value as 1.86 and 1.61 mL/min/g for stress MBF (sMBF) and MFR, respectively. The diagnosis performance of the quantitative diagnosis was higher than semi-quantitative method as (78.9% vs. 68.4%, 63.3% vs. 60.0%, 57.7% vs. 52.0%, 82.6% vs. 75.0%, 69.4% vs. 63.3%) for the criteria of ≥75% stenosis on CAG (all P<0.05) with optimal critical values as 1.71 and 1.15 mL/min/g. There was no significant difference between sMBF and MFR. Conclusions:The diagnostic efficiency by using the quantitative method of CZT dynamic SPECT imaging is superior to traditional semi-quantitative gated MPI for the diagnosis of CAD, which improved the diagnostic specificity and accuracy when the critical was stenosis ≥50%.

The goal of this study is to explore and evaluate the diagnostic values of myocardial blood flow (MBF), myocardial flow reserve (MFR) and relative flow reserve (RFR) obtained with low-dose dynamic CZT SPECT for patients with suspected or known coronary artery disease (CAD). Fifty-seven consecutive patients who underwent low-dose dynamic CZT SPECT and CAG were enrolled. MBF, MFR and RFR were calculated on the vessel level with dedicated quantitative software, and the difference and correlation of each parameter was compared according to the reference standard of stenosis ≥ 50% or ≥ 75% on CAG, respectively. ROC curves were made by stress MBF (sMBF), rest MBF (rMBF), MFR and RFR. The optimal cut-off values and corresponding diagnostic efficacy were obtained and compared with each other. Results indicated that when stenosis ≥ 50% or ≥ 75% on CAG was used as the reference standard at the vessel level, there was no statistically significant difference in rMBF between the negative group and the positive group (P > 0.05), and the sMBF and MFR in positive groups were significantly lower than that in the negative group (all P < 0.05). There was a moderate to significant correlation between sMBF and MFR, sMBF and RFR, MFR and RFR (all P < 0.0001). These results indicate that low-dose dynamic CZT SPECT imaging can easily obtain the sMBF, MFR and RFR, and there is a good correlation among the three parameters, which has a certain diagnostic value for patients with suspected or known CAD, and is a useful supplement to the conventional qualitative or semi-quantitative diagnostic methods.

Cardiac amyloidosis (CA) is a group of restrictive cardiomyopathies that have received increasing attention and awareness. With the advancement of noninvasive multimodality imaging techniques, the diagnostic efficacy and comprehensive assessment of CA have rapidly evolved. Here, we present two cases in which better diagnosis and evaluation were achieved using multimodality imaging techniques.Two patients with CA were diagnosed with transthyretin CA and immunoglobulin light-chain CA using clinical data, laboratory tests, ultrasound, nuclear medicine, coronary CT angiography, and cardiovascular magnetic resonance, respectively. This not only elucidated the diagnosis of CA but also provided a comprehensive and in-depth diagnosis of these two patients with CA using noninvasive multimodality imaging techniques through the detection of cardiac morphology and size, left ventricular function, myocardial injury, and coronary microvascular function. The disease processes and characteristics of these patients were comprehensively evaluated, especially the classified diagnosis of CA via radionuclide 99m Tc-PYP imaging and measurement of coronary flow reserve via quantitative radionuclide myocardial perfusion imaging for the diagnosis and evaluation of CA.Modern multimodality noninvasive imaging can complement each other's information and strengths and play important roles in the early diagnosis and treatment of patients with CA.