Objective To derive reference limits of cardiac functional parameters (CFP) determined by gated myocardial SPECT imaging, and to analyze the influence of gender, age and weight on CFP. Methods One hundred and seventy-five consecutive outpatients (89 males with age of (48.3±10.7) years and 86 females with age of (49.8±10.4) years) were defined as patients with low-likelihood coronary heart disease (LCHD). All patients underwent adenosine or exercise stress 99Tcm-MIBI G-MPI from February 2008 to April 2011. The EF, EDV and ESV of the left ventricle were measured by quantitative gated SPECT (QGS) software. The reference limits were derived by means of Gaussian distribution or percentiles. The influence of gender, age and weight on CFP was analyzed by multiple regressions for linear models. Two-sample t test was used to analyze data of 2 groups. Parameters between different age groups were compared by one-way analysis of variance. Results The lower reference limit of EF for males was 50%, the upper limit of EDV and ESV was 112 ml and 49 ml respectively. For females, the corresponding reference limits were 54%, 77 ml and 30 ml. Men had higher EDV, ESV (EDV: (75.8±18.3) ml vs (53.3±11.7) ml, t=9.35, P<001; ESV: (27.1±10.9) ml vs (14.3±7.9) ml, t=8.59, P<0.01) and lower EF than women ((65.1±76)% vs (74.7±10.0)%, t=-6.92, P<0.01). The incidence of small hearts in women was 76%(65/86). The gender and age was the primary and secondary predictors of both of EF and ESV, while the body weight was a significantly third predictor for cardiac volume. Patients were dived into different age (≤40 years, 41-49 years, ≥50 years) groups. For males, EDV, ESV and EF were not significantly different among the different age groups (F values: 1.106, 0.954, 1.029, all P>0.05). For females, EDV was not different (F=2408, P>005), while ESV and EF were significantly different among 3 groups (F values: 5.010, 6.229, both P<0.05). Conclusions The CFP determined by G-MPI in LCHD patients are significantly affected by gender and age. The age-related changes of CFP in males are different from those in females.

Objective To evaluate the effects of metabolic factors on the quality of 18F-fluorode oxyglucose (18F-FDG) myocardial metabolic imaging in coronary artery disease (CAD) patients with type 2 diabetes mellitus (T2DM). Methods Seventy CAD patients aged 60 years or over with T2DM were studied with myocardial 18 F-FDG dual isotope simultaneous acquisition (DISA) single photon emission computed tomography (SPECT). Fasting plasma glucose, total triglyceride (TG),total cholesterol (TC), high density lipoprotein-cholesterol (HDL-C), low density lipoprotein-eholesterol(LDL-C), insulin, C peptide and glyeosylated hemoglobia (HbAlc) were detected. Insulin resistance and islet β cell function were calculated by using the Homeostasis Model Assessment (HOMA) equation. Results Compared with the bad image quality group (36 cases), patients in the excellent image quality group (34 cases) were younger [with average age of (62.2±8.5) years vs. (67.6±8.3) years, P<0.01] and slimmer [with BMI of (24.7±2.6)kg/m2 vs. (26.1±2.5)kg/m2, P<0.05]. The levels of fasting insulin and C peptide were lower in the excellent image quality group than those in the bad image quality group [with fasting insulin level of 8.3 (5.1～12.4) mIu/L vs. 12.7,(6.1～17.9)mIu/L and C-peptide level of 0.6(0.5～0.9)nmol/L vs. 0.9(0.6～1.2)nmol/L, respectively,both P<0.05]. The HOMA insulin resistant index was reduced in the excellent image group [2.7(1.6～4.0) vs. 4.1(1.7～6.5), P<0.05]. Logistic regression analysis showed that obesity and age≥65 years were independent risk factors for image quality, with OR value of 3.73 (95% CI: 1.12～12.45,P=0.022)and 3.75 (95%CI:0.96～14.6,P=0.058)after adjustment of other metabolic factors. Conclusions Insulin resistance is the main factor that influences the quality of 18F-FDG myocardial metabolic imaging in patients with T2DM. In addition, age≥65 years and obesity are also risk factors for image quality.

Objective To explore the relationship between the index of SPECT myocardial viability teat of the left ventricle and long-term cardiovascular adverse events following the coronary artery bypass graft.Methods Clinical data were selected from the coronary-heart-disease patients with CABG and the isotopic SPECT test of myocardial viability prior to the operation in the Fuwai Cardiovascular Hospital,the Chinese Academy of Medical Science from January 1,1999 to December 31,2005.Total 709 patients were included in this study.Regular follow-up in patients was performed following operation.Investigate the nuclear medicine documents of the patients above;make the semi-quantitative scores of myocardial viability prior to operation by the 17-segment method of ventricle.Through the COX multi-factor analysis of the statistical methods to explore the relationship between the index of the myocardial viability and the long-term cardiac adverse events selected in advance.Results The mean duration of follow-up was(3.43±2.42)years.The COX multi-analysis revealed that the total score of left ventricular myocardial viability is the independent impact factors for long term cardiac death,long terrm re-hospitalization rate and long term composite end points events.The cut off values of total score of left ventricular myocardial viability for long term cardiac death,long term re-hospitalization rate and long term composite end points events is 15,9,13 respectively.Conclusion The total score of left ventricular myocardial viability of SPECT is independently associated with long-term events,and the cut values of myocardial viability total score for long-term cardiac death,re-hospitalization and composite MACE events are 15,9,and 13 respectively.For the groups with total scores above and below the cut off values,there is significant difference of long term cardiac events risk between groups.

Objective To explore the clinical value of 18F-FDG PET/CT in differentiating between cardiac benign and malignant lesions.Methods From September 2009 to September 2012,a total of 9 (7males,2 females,average age (46± 22) years) patients with space-occupying lesions of the heart underwent whole body 18F-FDG PET/CT.18 F-FDG PET/CT diagnosis was made according to morphologic features and SUVmax of lesions.The final diagnoses were confirmed by either histopathology or clinical data and follow-up.Two-sample t test was used for data analysis.Results Among 9 cases of cardiac occupying lesions,4 cases were malignant tumors,4 cases were benign tumors (including 2 lipomas,1 myxoma,and 1 fibroma),1 case was thrombus.The average SUVmax of malignant tumors was 18.99±14.58,which was significantly higher than that of benign tumors (2.35±1.46,t=-2.58,P＜0.05).With a cut-off SUVmax of 4.6,18F-FDG PET/CT could be used to noninvasively detect malignant tumors with a sensitivity of 4/4,specificity of 4/5,and accuracy of 8/9.Only 1 thrombus was misdiagnosed.Conclusion 18F-FDG PET/CT can aid the noninvasive differential diagnosis of cardiac malignant tumors from benign lesions.

Objective To explore the imaging characteristics and the complementarity of contrast?enhanced cardiac magnetic resonance CMR and nuclear myocardial perfusion/metabolic imaging in the evaluation of myocardial viability in patients with ischemic cardiomyopathy. Methods A total of 111 patients with diagnosed coronary artery disease and left ventricular dysfunction were retrospectively enrolled in this study. All patients underwent CMR and nuclear myocardial imaging within 1 month. Cine CMR was employed to evaluate cardiac function and wall motion. Contrast?enhanced CMR and myocardial perfusion/metabolic images were quantitatively assessed using a standard 17-segment and 5-score system. Dysfunctional segments were classified as viable or non?viable based on contrast?enhanced CMR and myocardial perfusion/metabolic imaging, respectively. No enhancement or sub?endocardial enhancement was defined as viable, while transmural enhancement was defined as non?viable. Severely matched perfusion/metabolism defects on nuclear imaging were assigned as non?viable while other patterns were considered as viable. Kappa index was calculated to evaluate the diagnostic concordance in assessing myocardial viability between contrast?enhanced CMR and myocardial perfusion/metabolic imaging. Results Among 1 887 segments in 111 patients, 80.3%(1 516/1 887) were dysfunctional. Of them, 63.3%(959/1 516) were viable and 36.7%(557/1 516) were non?viable on contrast?enhanced CMR, while 79.7%(1 208/1 516) were viable and 20.3%(308/1 516) were non?viable on nuclear myocardial imaging. The two modalities had a moderate concordance (Kappa=0.46,P<0.01). In segments with normal perfusion and metabolism, 73.9% (431/583) had various extent of enhancement but most of them(84.2%, 363/431) were subendocardial. On the other hand, 21.0%(117/557) segments with transmural enhancement had hibernating myocardium on nuclear imaging. Conclusions Contrast?enhanced CMR and nuclear myocardial imaging have a moderate concordance in the evaluation of myocardial viability in ischemic cardiomyopathy. Combination of the two modalities is expected to improve the diagnostic accuracy in assessing myocardial viability.

Objective To prospectively compare cadmium-zinc-telluride (CZT) SPECT gated myocardial perfusion imaging (GMPI),conventional SPECT MPI and cardiac MRI for the assessment of left ventricular volume and ejection fraction in patients with heart failure.Methods From July 2016 to October 2016,a total of 35 patients (27 males,8 females,average age:(52.7±14.9) years) with heart failure were consecutively included.All patients underwent CZT SPECT GMPI,conventional SPECT GMPI and cardiac MRI within 7 d.LVEDV,LVESV and LVEF of three imaging modalities were calculated.One-way analysis of variance,Pearson correlation analysis and Bland-Altman analysis were used.Results CZT SPECT showed excellent correlation with conventional SPECT for LVEDV,LVESV and LVEF (r values:0.983,0.986 and 0.910,respectively;all P＜0.001).Bland-Altman analysis revealed good agreement between CZT SPECT and conventional SPECT for LVEDV,LVESV and LVEF.The correlation between CZT SPECT and cardiac MRI for LVEDV,LVESV and LVEF were all significant (r values:0.864,0.896 and 0.836,respectively;all P＜0.001).Compared with cardiac MRI,CZT SPECT showed systemic underestimation of LVEDV and LVESV and good agreement of LVEF by Bland-Altman analysis.Conclusions CZT SPECT has high clinical value for patients with heart failure.Despite underestimating LVEDV and LVESV,it correlated well with cardiac MRI.It also has a good agreement with conventional SPECT on left ventricular volume and LVEF.

Dynamic ~(13)N-NH_3 positron emission tomography (PET) imaging was performed in 8 normal subjects and 6 cases of hypopituitarism. The pituitary images were small and delayed, and blood perfusion and radioactive uptake were decreased in hypopituitarism. ~(13)N-NH_3 PET imaging shows diagnostic value in hypopituitarism.

Objective: To assess the effect of coronary collateral circulation (CCC) on myocardial viabilityin patients with chronic total occlusion of left anterior descending (LAD) artery. Methods: A total of 101 consecutive patients with confirmed diagnosis of total LAD occlusion in our hospital were enrolled. Rest 99mTc-MIBISPECT myocardial perfusion and 18F-FDG PET were performed, in addition all patients received coronary angiography (CAG) at 3 months front and back. Both images were reconstructed in the same machine and QPS software was used to obtain the summed rest score (SRS), abnormal resting total perfusion defect (TPD), viable and non-viable myocardium, LVEDV, LVESV and LVEF in relevant patients. Based on CAG result, the patients were divided into 2 groups: CCC group, n=39 and No CCC group, n=62; according to existing old myocardial infarctionand location of LAD occlusion, the patients were further divided into 4 subgroups. The above parameters were compared among different groups. Results: There were 86 male and 15 female patients with the mean age at (59.92±11.43) years. Relevant parameters in CCC group and No CCC groupwere as in SRS: (21.23±9.68) vs (28.56±8.76), TPD: (30.03±13.69) %vs (40.37±12.50) %, viable myocardium: (21.77±13.12) % vs (13.66±9.23) %, non-viable myocardium (8.28±8.58) %vs (27.40±12.97) %, all P<0.05; in LVEDV: (109.82±30.01) ml vs (173.71±57.69) ml, LVESV: (62.82±22.39) ml vs (122.53±51.66) ml, LVEF: (43.85±8.46) % vs (31.03±8.30) %, all P<0.05. Conclusion: Our preliminary study found that CCC could maintain left ventricular rest perfusion, myocardial viability and protect cardiac function in patients with chronic total LAD occlusion.

Objective To evaluate the effect and mechanism of bone morrow MSCs transplantation in swine with AMI by cell biology and molecular imaging methods including PET/CT, SPECT, and MRI. Methods Twenty?four Chinese mini?swine ( ( 25 ± 5 ) kg ) were randomly divided into 2 groups: MSCs group ( n=12) and control group ( n=12) . Myocardial infarction was induced in swine hearts by occlusion of the LAD. Thirty minutes later, the MSCs group received autologous MSCs transplantation through in?tramyocardial injection into the peri?infarcted areas (2×107,2 ml) and the control group was subjected to cell culture medium in the same way. At the 1st and 4th weeks after MSCs transplantation, myocardial glu?cose metabolism, myocardial perfusion and cardiac function were evaluated in the two groups through PET/CT, SPECT and MRI. The minimum FDG mean signal intensity ( MSI ) , summed MSI, SRS, SRS%, LVEF, ESV, stroke volume ( SV) and cardiac output ( CO) were calculated. On the 4th week, HE and Masson′s Trichrome stains were performed. Mann?Whitney u test and non?parametric Wilcoxon test were used. Results (1) As evaluated by PET in the 1st week, the MSI and summed MSI in MSCs group were less than those in control group ( 22. 10 ± 3. 18 vs 35. 70 ± 3. 02, z=-2. 65; 1 013. 50 ± 29. 37 vs 1 084. 00 ± 21?15, z=-1.97;both P<0.05) . Compared to the minimum MSI and summed MSI in the 1st week, those in MSCs group increased significantly (34.00±4.25, z=-2.81;1 075.50±28.30, z=-2.80;both P<0?01) in the 4th week. SRS and SRS% decreased in the 4th week compared to those in the 1st week (20.20±2.24 vs 23.80±1.58, (29.80±3.31)% vs (35.10±2.34)%;both z=-2.08, both P<0.05). The averaged MSI in left ventricular infarction area (MSI<70) also increased (56.25±3.54 vs 48.14±2.71;z=-2.80, P<0.01). The a?bove?mentioned parameters had no statistically significant differences in the 4th week compared to those in the 1st week in the control group (all P>0.05). (2) In the 1st week, the perfusion variables had no signifi?cant differences between the two groups ( P>0.05) . There was no significant difference in any perfusion vari?ables between the 1st and 4th weeks in the two groups, respectively (P>0.05). (3) As evaluated by MRI, the cardiac functional parameters had no significant differences between the two groups at the 1st week. In the MSCs groups, LVEF increased significantly ((54.41±2.62)% vs (47.54±2.43)%;z=-2.60, P<0.01) and ESV reduced significantly ((22.85±1.91) vs (27.07±1.67) ml;z=-2.70, P<0.01) in the 4th week com?pared to those in the 1st week; SV and cardiac CO in the 4th week also increased significantly ((29.35± 1?84) vs (26.52±1.46) ml, (2.23±0.14) vs (1.96±0.13) L/min;z=-2.09 and -1.99, both P<0?05). In the control group, there were no significant differences in the cardiac functional parameters between the 1st and 4th weeks ( all P>0.05) . Conclusions Four weeks after MSCs transplantation for AMI, cardiac func?tion and myocardial glucose metabolism improved significantly but without significant myocardial perfusion improvement. Therefore, the cardiac function improvement might be associated with increased myocardial glucose metabolism.