To investigate the relationship between metabolic dysfunction–associated steatotic liver disease (MASLD) and myocardial ischemia in patients with suspected or known coronary artery disease (CAD). This retrospective study enrolled 281 patients with suspected or known CAD who underwent single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) at the Third Affiliated Hospital of Soochow University from January 1, 2022, to December 31, 2023. The mean CT values of the liver and spleen, coronary artery calcification score (CACS), and epicardial fat volume (EFV) were acquired through non-enhanced computed tomography (CT). Myocardial ischemia is defined by SDS ≥ 2 detected by MPI. Obstructive CAD is defined as the degree of coronary artery lumen narrowing ≥ 50

Background:The impact of epicardial adipose tissue (EAT) on the risk of non-obstructive coronary artery disease (CAD) remains unclear. This study aims to investigate the association between EAT and ischemia with non-obstructive coronary arteries (INOCA). Methods:This study enrolled 281 patients with angina or other symptoms suggestive of myocardial ischemia who underwent single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). All patients had confirmed non-obstructive coronary artery disease (stenosis <50%) by either coronary angiography (CAG) or coronary CT angiography (CCTA) within 3 months before or after MPI. Based on MPI results, patients were categorized into ischemic and non-ischemic groups. Epicardial adipose tissue (EAT) density and volume were measured, and relevant clinical parameters were collected for analysis. Results:The results revealed that 37.72% of the patients had INOCA, and these patients exhibited significantly higher body mass index (BMI) and EAT density. No statistically significant difference in EAT volume was observed between groups. Both EAT density (OR = -1.846, 95% CI: 1.353-2.559, p < 0.05) and volume (OR = -1.703, 95% CI: 1.151-2.551, p < 0.05) were identified as independent risk factors for INOCA. Furthermore, EAT density demonstrated a linear relationship with disease risk. In statin users, the positive association between EAT density and INOCA was attenuated. (β = -0.039, p = 0.046). Conclusions:EAT density is an independent risk factor for INOCA, with its increase showing a linear association with INOCA risk. Further, statin use was associated with a reduction in this EAT density-related INOCA risk.

BACKGROUND:Atrial fibrillation, one of the most common types of arrhythmia, is a major risk factor for stroke. Previous studies have demonstrated cognitive decline in atrial fibrillation patients regardless of stroke comorbidity. This study aimed to investigate the relationship between cerebral metabolic alterations and cognitive impairment in stroke-free atrial fibrillation patients. METHODS:In the retrospective cohort study, we enrolled 68 stroke-free atrial fibrillation patients and 68 age-matched sinus rhythm controls who underwent 18F-fluorodeoxyglucose PET-computed tomography imaging between 1 January 2018 and 31 December 2022 in the third Affiliated Hospital of Soochow University. Regional cerebral metabolism was assessed using DPABI software, with the standardized uptake value ratio (SUVR) of regions of interest calculated as the average standardized uptake value (SUV mean ) of specific brain regions divided by the average SUV of the cerebellum. Cognitive performance was assessed using the Mini-Mental State Examination (MMSE). The MMSE has a total score of 30 points, with scores <24 indicating cognitive impairment. Clinical data, electrocardiograms, echocardiograms, and other relevant information were systematically collected. Correlation analyses were performed to investigate the association between metabolic changes and cognitive impairment. RESULTS:Cognitive assessment using the MMSE revealed significantly lower scores in atrial fibrillation patients compared to control [25.00 (24.00-26.00) vs. 27.00 (25.00-28.00), P  < 0.001] and the prevalence of cognitive impairment was significantly higher in the atrial fibrillation group than in the control group (17.64% vs. 4.41%, P  = 0.012). Regional cerebral metabolic analysis demonstrated widespread SUVR reductions in atrial fibrillation patients across multiple cognition-related regions, including the frontal, temporal, parietal, and occipital lobes, cingulate gyrus, thalamus, basal ganglia, and cerebellum. Multivariable logistic regression identified significant inverse associations between elevated SUVR values and cognitive impairment in the right calcarine fissure and surrounding cortex (Calcarine_R: adjusted OR = 0.004, P  = 0.033), bilateral lingual gyrus (Lingual_L/R: adjusted OR = 0.002, P  < 0.04), and Lobule VI-VIII of vermis (Vermis_6/7: adjusted OR = 0.000, P  < 0.035). Mediation analysis confirmed these regions as significant pathways linking atrial fibrillation to cognitive dysfunction, with Calcarine_R showing the strongest mediation effect (proportion: 40.80% crude, 36.30% adjusted; all P  < 0.05). CONCLUSION:These findings suggest that stroke-free atrial fibrillation patients exhibit abnormal cerebral metabolic patterns in specific brain regions, and some of the abnormal cerebral metabolic activities are closely linked to cognitive decline. These metabolic alterations may serve as potential neurobiological markers for predicting cognitive impairment in stroke-free atrial fibrillation patients.

Objective Major adverse cardiovascular events (MACE) still occur in the normal left ventricular ejection fraction (LVEF) patients with coronary artery disease (CAD). Currently, there are no studies related to the prognostic value of left ventricular diastolic dyssynchrony (LVDD) in combination with perfusion, systolic dyssynchrony, and cardiovascular risk factors in patients with normal LVEF. Therefore, we aimed to investigate the incremental prognostic value of LVDD in patients with normal LVEF and to establish a model to predict MACE. Methods This study included 239 suspected or known CAD patients with a normal LVEF who underwent gated single-photon emission computerized tomography myocardial perfusion imaging. Clinical data such as age, sex, and cardiovascular risk factors were collected. Myocardial perfusion, and left ventricular dyssynchrony parameters were assessed using QPS and Emory Toolbox software, respectively. The least absolute shrinkage and selection operator and multivariable Cox regression were used to select the variables. Results The subjects were followed up for a total of 73.2±16.4 months and MACE occurred in 28 patients. In multivariate Cox regression, rest diastolic bandwidth (BW) was closely related to MACE [hazard ratio (95% confidence interval), 10.78 (1.65–70.35); P =0.013]. The C-index of the model was increased from 0.748 to 0.783 by increasing the rest diastolic BW on the basis of summed difference score (SDS), stress systolic SD, age, hypertension, and chest pain ( P <0.001). A final model for predicting MACE was constructed based on age, hypertension, chest pain, SDS, stress systolic SD, and rest diastolic BW. The C-index of the model was 0.783, and the area under the curves of the model predicting the occurrence of 3-year and 5-year MACE events were 0.766 and 0.827, respectively. The calibration curve showed a good calibration of the model. Conclusion LVDD is associated with MACE in patients with normal LVEF. In addition, based on SDS, stress systolic SD, age, hypertension, and chest pain, rest diastolic BW had an incremental predictive value for MACE.

Background: In type 2 diabetes mellitus (T2DM) patients, left ventricular systolic dyssynchrony (LVSD) with normal left ventricular ejection fraction (LVEF) and normal myocardial perfusion could referred to as subclinical myocardial damage, which is difficult to diagnose at an early stage. Epicardial adipose tissue, a distinctive heart-specific visceral fat, is closely related to various cardiovascular diseases. The objective of this study was to investigate the correlation between epicardial fat volume (EFV) and subclinical myocardial damage in T2DM patients. Methods: This retrospective cross-sectional study included 117 T2DM patients with normal myocardial perfusion by single photon emission computed tomography-computed tomography (SPECT-CT) and normal LVEF by echocardiography. The study was conducted from January 2018 to December 2022. Patient data were collected through electronic medical records including basic patient information, medical history, laboratory tests, and medication data. The EFV was quantified through a non-contrast CT scan. Quantitative indicators of LVSD including phase standard deviation (PSD) and phase histogram bandwidth (PBW) were obtained through phase analysis of the gated rest myocardial perfusion imaging (MPI). Additionally, 83 healthy individuals at the same time were selected to gain the reference threshold of LVSD indicators (13.1 degrees for PSD and 37.6 degrees for PBW). Univariate and multivariable logistic regression models were performed to analyze factors influencing LVSD. A generalized additive model (GAM) was applied to explore the relationship between EFV and LVSD. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of EFV for LVSD. Results: Among all patients, 32 (27.4%) patients had LVSD. Compared with the non-LVSD group, the body mass index (BMI) and EFV were higher in the LVSD group (25.83 +/- 2.66 vs. 23.94 +/- 3.13 kg/m(2); 142.41 +/- 44.17 vs. 108.01 +/- 38.24 cm(3), respectively, both P<0.05). Multivariate regression analysis revealed that EFV was independently associated with LVSD [odds ratio (OR) =1.19; 95% confidence interval (CI): 1.06-1.34; P=0.003]. Age, BMI, incidence of hypertension, and LVSD were increased with tertiles of EFV (all P<0.05). The GAM indicated a linear association between EFV and LVSD. The ROC curve analysis concluded that the area under the curve (AUC) of EFV for predicting subclinical myocardial damage in T2DM patients was 0.732 (95% CI: 0.633-0.831, P<0.001), with the optimal threshold of 122.26 cm(3), sensitivity of 71.9%, and specificity of 69.4%. Conclusions: EFV is an independent risk factor for LVSD in T2DM patients with normal LVEF and normal MPI, which could potentially serve as a novel imaging marker and a potential therapeutic target for subclinical myocardial damage.

Background: Atrial fibrillation (AF) has been identified to increase stroke risk, even after oral anticoagulants (OACs), and the recurrence rate is high after radiofrequency catheter ablation (RFCA). Inflammation is an essential factor in the occurrence and persistence of AF. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) is an established molecular imaging modality to detect local inflammation. We aimed to investigate the relationship between atrial inflammatory activity and poor prognosis of AF based on 18F-FDG PET/CT.Methods: A total of 204 AF patients including 75 with paroxysmal AF (ParAF) and 129 with persistent AF (PerAF) who underwent PET/CT before treatment were enrolled in this prospective cohort study. Clinical data, electrocardiograph (ECG), echocardiography, and cardiac 18F-FDG uptake were collected. Follow-up information was obtained from patient clinical case notes or telephone reviews, with the starting point being the time of PET/CT scan. The follow-up deadline was either the date of AF recurrence after RFCA, new-onset stroke, or May 2023. Cox proportional hazards regression models were used to identify predictors of poor prognosis and hazard ratios (HRs) with 95% confidence intervals (CIs) was calculated.Results: Median follow-up time was 29 months [interquartile range (IQR), 22-36 months]. Poor prognosis occurred in 52 patients (25.5%), including 34 new-onset stroke patients and 18 recrudescence after RFCA. The poor prognosis group had higher congestive heart failure, hypertension, age >= 75 years (doubled), diabetes mellitus, prior stroke or transient ischemic attack (TIA) or thromboembolism (doubled), vascular disease, age 65-74 years, sex category (female) (CHA2DS2-VASc) score [3.0 (IQR, 1.0, 3.75) vs. 2.0 (IQR, 1.0, 3.0), P=0.01], right atrial (RA) wall maximum standardized uptake value (SUVmax) (4.13 +/- 1.82 vs. 3.74 +/- 1.58, P=0.04), higher percentage of PerAF [39 (75.0%) vs. 90 (59.2%), P=0.04], left atrial (LA) enlargement [45 (86.5%) vs. 104 (68.4%), P=0.01], and RA wall positive FDG uptake [40 (76.9%) vs. 79 (52.0%), P=0.002] compared with the non-poor prognosis group. Univariate and multivariate Cox proportional hazard regression analysis concluded that only CHA2DS2-VASc score (HR, 1.29; 95% CI: 1.06-1.57; P=0.01) and RA wall positive FDG uptake (HR, 2.68; 95% CI: 1.10-6.50; P=0.03) were significantly associated with poor prognosis.Conclusions: RA wall FDG positive uptake based on PET/CT is tightly related to AF recurrence after RFCA or new-onset stroke after antiarrhythmic and anticoagulation treatment.

Background: Recent studies have shown that resting amygdalar activity is associated with cardiovascular disease. Nevertheless, the underlying mechanisms that link resting amygdalar activity with persistent atrial fibrillation (PerAF) remain to be comprehensively delineated. We aimed to estimate the association between resting amygdalar activity, right atrium (RA) inflammatory activity, and PerAF. Methods: In the retrospective cohort study, 18F-fluorodeoxyglucose positron emission tomographycomputed tomography (18F-FDG-PET/CT) imaging was performed in 104 patients with AF between January 1, 2018, and December 31, 2022 in the third Affiliated Hospital of Soochow University. Clinical data, electrocardiograms, echocardiographic assessments, and cardiac 18F-FDG uptake measurements were systematically gathered. Validated methodologies were employed to assess resting amygdalar activity, right atrium target:background ratio (RATBR), and bone-marrow activity (BMA). Associations between resting amygdalar activity and PerAF were assessed via a logistic regression model and mediation (path) analyses. Results: Among the patients included, 60 (57.7%) had PerAF. Compared with patients with paroxysmal AF (ParAF), those with PerAF had higher resting amygdalar activity (1.11 +/- 0.16 vs. 1.47 +/- 0.27), BMA (1.66 +/- 0.48 vs. 2.12 +/- 0.65), and RATBR (1.55 +/- 0.36 vs. 2.31 +/- 0.73) (all P values <0.001). Resting amygdalar activity demonstrated a statistically significant correlation with BMA (r=0.38; P<0.001) and RATBR (r=0.44; P<0.001). BMA significantly mediated the associations between resting amygdalar activity and RATBR, accounting for 50.2% [95% confidence interval (CI): 35.8-76.7%] of this association. Resting amygdalar activity and RATBR emerged as the sole independent variable for PerAF (odds ratio =6.81; 95% CI: 2.34- significantly mediated the associations between resting amygdalar activity and PerAF, accounting for 33.2% (95% CI: 16.6-52.4%) of this association. Conclusions: Resting amygdalar activity and RATBR evaluated by PET/CT were significantly associated with PerAF. The association of testing amygdalar activity with PerAF was in part mediated by RA inflammatory activity, which could be a potential therapeutic target for PerAF. Further prospective research is needed to determine the generalizability of these findings.

Background: Prosthetic valve endocarditis continues to be a lifethreatening complication of valve replacement.Accurate and early detection is necessary to facilitate appropriate treatment.Methods: This is a retrospective study of patients with a high clinical suspicion of prosthetic valve endocarditis and with an equivocal, negative, or non-diagnostic transesophageal echocardiogram who were sent for PET FDG imaging for further evaluation of PVE.The patients were sent at the discretion of the primary care team and, in most cases, infectious diseases (no protocol was in place).Standard PET protocol for FDG inflammation was followed.Results: 36 patients had PET FDG imaging.89% (32 of 36) had a negative, equivocal or non-diagnostic transesophageal echocardiogram prior to PET FDG.75% (27 of 36) of the FDG PET studies were positive for inflammation consistent with prosthetic valve endocarditis.12% (4 of 32) who had an initially negative TEE and positive PET FDG scan, had a subsequent transesophageal echocardiogram that was consistent with PVE.Chart review was done all patients for treatment and outcome, infectious diseases team was involved in all cases Conclusions: PVE is difficult to diagnose and treat.FDG PET may be helpful in the diagnosis of PVE when there is a high index of clinical suspicion in the setting of a non-diagnostic echocardiogram.Further study with longitudinal follow-up is needed to determine clinical outcomes after FDG-PET.

Background Most coronary artery disease (CAD) patients with a normal left ventricular ejection fraction (LVEF) experience a poor prognosis. Single-photon emission computerized tomography (SPECT)–myocardial perfusion imaging (MPI), a routine examination, is useful in assessing risk and predicting major adverse cardiovascular events (MACEs) in populations with suspected or known CAD. SPECT/CT is a “one-stop shop” examination, which, through non-contrast CT, can produce attenuation correction for MPI and obtain information on coronary artery calcium (CAC) and epicardial fat volume (EFV) simultaneously. This study aims to investigate the predictive and incremental value of EFV to MPI for MACE in Chinese populations with suspected or known CAD with a normal LVEF. Methods and results We retrospectively studied 290 suspected or known CAD inpatients with a normal LVEF who underwent SPECT/CT between February 2014 and December 2017. Abnormal MPI was defined as a summed stress score ≥4 or summed difference score ≥2. EFV and CAC were calculated using non-contrast CT. The end date of follow-ups was in February 2022. The follow-up information was obtained from the clinical case notes of the patients or reviews of telephone calls. MACE was defined as cardiac death, late coronary revascularization ≥3 months after MPI, non-fatal myocardial infarction, angina-related rehospitalization, heart failure, and stroke. During the 76-month follow-up, the event rate was 32.0% (93/290). Univariate and multivariate Cox regression analyses concluded that high EFV (>108.3 cm3) [hazard ratio (HR): 3.3, 95% CI: 2.1–5.2, P < 0.000] and abnormal MPI (HR: 1.8, 95% CI: 1.1–2.8, P = 0.010) were independent risk factors for MACE. The event-free survival of patients with high EFV was significantly lower than that of the low EFV group (log-rank test P < 0.001). In the subgroup with normal MPI, high EFV was associated with reduced event-free survival (log-rank P < 0.01), with a higher annualized event rate (8.3% vs. 1.9%). Adding high EFV to MPI could predict MACEs more effectively, with a higher concordance index (0.56–0.69, P < 0.01), higher global chi square (7.2–41.4, P < 0.01), positive integrated discrimination improvement (0.10, P < 0.01), and net reclassification index (0.37, P < 0.01). Conclusions In Chinese populations with suspected or known CAD with normal LVEF, high EFV was an independent risk factor for MACE after adjusting for traditional risk factors, CAC and MPI. In subgroups with normal MPI, EFV could also improve risk stratification. Adding EFV to MPI had an incremental value for predicting MACE.

Aim Atrial fibrillation (AF) is a progressive disease from paroxysmal to persistent, and persistent AF (PerAF) had worse prognosis. AF has potential link with inflammation, but it is not clear whether PerAF or paroxysmal AF (ParAF) is more closely related to inflammation. On the basis of inhibiting myocardial physiological uptake, 18 F-fluorodeoxyglucosepositron emission tomography/computed tomography ( 18 F-FDG PET/CT) is an established imaging modality to detect cardiac inflammation. We aimed to decipher the association between AF and atrial inflammatory activity by 18 F-FDG PET/CT. Methods Thirty-five PerAF patients were compared to age and sex matched ParAF group with baseline 18 F-FDG PET/CT scans prior to radiofrequency catheter ablation (RFCA) in the prospective case-control study. High-fat and low-carbohydrate diet and prolonged fast (HFLC+Fast) was applied to all AF patients before PET/CT. Then 22 AF patients with positive right atrial (RA) wall FDG uptake (HFLC+Fast) were randomly selected and underwent HFLC+Fast+heparin the next day. The CHA2DS2-VASc score was calculated to evaluate the risk of stroke. Clinical data, ECG, echocardiography, and atrial 18 F-FDG uptake were compared. Results PerAF patients had significantly higher probability of RA wall positive FDG uptake and higher SUVmax than ParAF group [91.4% VS. 28.6%, P < 0.001; SUVmax: 4.10(3.20–4.90) VS. 2.60(2.40–3.10), P < 0.001]. Multivariate logistic regression analyses demonstrated that RA wall SUV max was the independent influencing factor of PerAF (OR = 1.80, 95%CI 1.02–3.18, P = 0.04). In 22 AF patients with RA wall positive FDG uptake (HFLC+Fast), the “HFLC+Fast+Heparin” method did not significantly change RA wall FDG uptake evaluated by either quantitative analysis or visual analysis. High CHA2DS2-VASc score group had higher RA wall 18 F-FDG uptake [3.35 (2.70, 4.50) vs, 2.8 (2.4, 3.1) P = 0.01]. Conclusions RA wall FDG positive uptake was present mainly in PerAF. A higher RA wall 18 F-FDG uptake was an independent influencing factor of PerAF. RA wall FDG uptake based on 18 F-FDG PET/CT may indicate pathological inflammation. Trial registration http://www.chictr.org.cn , ChiCTR2000038288.

We read with great interest the recent article by Flavio et al. [ [1] Biccire F.G. Tanzilli G. Prati F. Sammartini E. Gelfusa M. Celeski M. et al. Prediction of new onset atrial fibrillation in patients with acute coronary syndrome undergoing percutaneous coronary intervention using the C2HEST and mC2HEST scores: a report from the multicenter REALE-ACS registry. Int. J. Cardiol. 2023; 386: 45-49 Abstract Full Text Full Text PDF PubMed Scopus (0) Google Scholar ], which clarified the C2HEST scoring system to evaluate the development of new onset atrial fibrillation (NOAF) in patients with acute coronary syndrome after percutaneous coronary intervention. The risk of NOAF showed a gradual increase with C2HEST score. In addition to express our appreciation for the in-depth research, we would also like to raise a few comments.

BackgroundAtrial fibrillation (AF) is a common arrhythmia, and its most severe and dreaded complication is stroke. The CHA2DS2-VASc score is currently recommended for stroke risk assessment in AF. We aimed to explore the relationship between atrial FDG uptake and stroke and whether atrial FDG uptake could provide incremental value above the CHA2DS2-VAS score to predict stroke in AF by 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT).Materials and MethodsFrom September 2017 to December 2020, we retrospectively enrolled 230 patients (115 with AF and 115 without AF as the non-AF group, matched for the date of PET/CT examination and the basic characteristics of the patient) who underwent 18F-FDG PET/CT due to tumor screening or preoperative staging after prolonged fasting and followed up for at least 12 months from the date of PET/CT examination; the endpoint event is the occurrence of stroke. We visually and quantitatively analyzed 18F-FDG uptake in the right and left atria (RA/LA), right and left atrial appendage (RAA/LAA), right and left ventricle (RV/LV), and collected clinical features. In addition, according to the endpoint event (stroke), the enrolled population was divided into the stroke group and non-stroke group, and relevant clinical features and atrial FDG uptake indicators of the two groups were analyzed. Univariate and multivariate Cox regression analyzes were used to analyze the risk factors of stroke events. The Kaplan–Meier survival curve of atrial FDG uptake was drawn, and the log-rank method was used to compare the differences in the survival curves of the two groups. Receiver operating characteristic (ROC) curves were used to examine the discriminatory power of atrial FDG uptake in predicting stroke and determine whether the addition of atrial FDG uptake improves predictive value beyond the CHA2DS2-VASc score for stroke.ResultsIn the AF group, more than half of patients had RA FDG uptake and one-fifth had LA FDG uptake, while one patient had RA FDG uptake and two patients had LA FDG uptake in the non-AF group. In quantitative analysis, the maximum standardized uptake value (SUVmax) of the RA and LA in the AF group was significantly higher than that of the non-AF group (all P < 0.001). We followed up the patients for 28 ± 10 months, and finally, 31 patients had stroke. In the stroke group, atrial fibrillation, RA SUVmax, RAA SUVmax, LAA SUVmax, age ≥ 75 years, and left atrial dilation were significantly higher than those of the non-stroke group (all P < 0.05). Multivariate Cox regression analysis showed that high RA SUVmax (RA SUVmax ≥ 2.62) was an independent risk factor for stroke (HR = 4.264, 95% CI 1.368–13.293, P = 0.012). By using the log-rank test, patients with high RA SUVmax had a significantly higher incidence of stroke compared with patients with low RA SUVmax (P < 0.001). Addition of high RA SUVmax to the CHA2DS2-VASc score could predict stroke more effectively, with a larger AUC 0.790 (P < 0.001).ConclusionThis study found a significant correlation between atrial FDG uptake and AF, especially in RA. Meanwhile, RA FDG uptake is an independent risk factor for stroke, and patients with high RA SUVmax have a significantly higher risk of stroke. Moreover, RA FDG uptake improves prediction of stroke above the CHA2DS2-VASc score in patients with AF.

Objective:To evaluate the left ventricular diastolic dyssynchrony (LVDD) and its influencing factors early after acute myocardial infarction (AMI) using phase analysis of SPECT gated myocardial perfusion imaging (GMPI).Methods:Bama miniature swines ( n=16) were subjected to establish AMI models. GMPI was performed before and 1 d after AMI to obtain the extent of myocardial perfusion defect (Extent, %) and left ventricular systolic dyssynchrony (LVSD)/LVDD parameters, namely the phase histogram bandwidth (PBW) and phase standard deviation (PSD). Meanwhile, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), and the ratio of early to late peak mitral diastolic flow (E/A) were obtained by echocardiography. Independent-sample t test, paired t test and Pearson correlation analysis were used to analyze the data. Results:Sixteen AMI swines were successfully created. Compared to baseline, Extent, LVEDV and LVESV significantly increased on 1 d after AMI ( t values: -11.14, -4.55, -6.12, all P<0.001), while LVEF and E/A significantly decreased ( t values: 10.16, 2.18, P<0.001, P=0.046). GMPI showed that the LVDD parameters PBW and PSD increased significantly on 1 d after AMI when compared to those at baseline((142.25±72.06)° vs (33.06±8.98)°, (56.15±26.71)° vs (12.51±5.13)°; t values: -6.11, -6.60, both P<0.001). There were significant differences between LVSD parameters and LVDD parameters (PBW: (109.06±62.40)° vs (142.25±72.06)°, PSD: (44.40±25.61)° vs (56.15±26.71)°; t values: -2.73, -2.20, P values: 0.016, 0.044). LVDD parameters PBW, PSD were negatively correlated with E/A after AMI ( r values: -0.569, -0.566, P values: 0.021, 0.022), and positively correlated with the Extent ( r values: 0.717, 0.634, P values: 0.002, 0.008). The phase analysis of SPECT GMPI to evaluate LVDD showed good intra-observer and inter-observe reproducibility (intraclass correlation coefficient (ICC): 0.953-0.984, all P<0.001). Conclusions:LVDD occurs early on 1 d after AMI, and can reflect left ventricular diastolic dysfunction. The Extent is correlated with LVDD significantly. Phase analysis of SPECT GMPI is an accurate method to evaluate LVDD and left ventricular diastolic function.