Background: The identification of high-risk coronary artery disease (HRCAD) is important in diabetes mellitus (DM) patients. However, the reliability of current models to predict HRCAD has not been fully investigated. Thus, we aimed to validate and compare CONFIRM and PROMISE high-risk model (CHM and PHM) in DM patients. Methods: 5936 symptomatic DM patients who underwent coronary computed tomographic angiography (CCTA) were identified. Probability of HRCAD for each patient was estimated based on CHM and PHM, respectively. We used Area under the receiver operating characteristic curve (AUC), integrated discrimination improvement (IDI), net reclassification improvement (NRI) and Hosmer-Lemeshow (H-L) test to evaluate model’s predictive accuracy. Results: Overall, 470 (8%) patients had HRCAD on CCTA. There was no difference between the AUC for CHM and PHM (0.744 v.s. 0.721, p = 0.0873). Compared to CHM, PHM demonstrated a positive IDI (3.08%, p < 0.0001), positive NRI (12.50%, p < 0.0001) and less discrepancy between observed and predicted probabilities (H-L χ2 for CHM: 35.81, p < 0.0001; H-L χ2 for PHM: 23.75, p = 0.0025). Conclusions: Compared to CHM, PHM was associated with a more accurate prediction for HRCAD and might optimize downstream management strategy in symptomatic patients with DM. Clinical Trial Registration: ClinicalTrials.gov (NCT04691037).

The study aimed to investigate the role of low-dose dobutamine stress myocardial contrast echocardiography (MCE) in evaluating myocardial local microcirculation and predicting cardiac function recovery in patients with myocardial infarction. A total of 50 patients with acute myocardial infarction (AMI) were enrolled in the present study. Positron emission tomography was used as a gold standard to determine viable/non-viable myocardial segments in infarcted myocardial region. MCE and dobutamine stress MCE were carried out 72 h after PCI. MCE was carried out again to evaluate myocardial condition at 6 months after PCI. As compared with normal myocardial segments, resting MCE revealed a significant decrease of the values of A (the peak intensity of the time-perfusion intensity curve, reflecting the myocardial blood volume), β (the slope of the curve, reflecting the myocardial blood flow (MBF) velocity) and A x β (reflecting MBF) of viable and non-viable myocardial segments. After being challenged by dobutamine, the values of A, β and A x β of normal coronary blood supply areas were significantly increased; while the segments A and A x β of viable myocardium were markedly decreased. Patients were further divided into two groups based on the changes in the contrast-enhanced index (CSI) following dobutamine loading. In the dobutamine stress echocardiography-positive group (the CSI increased or decreased by >0.2), the left ventricular ejection fraction was significantly increased and pro-B-type natriuretic peptide significantly decreased at 6 months following intervention. Low-dose dobutamine stress MCE was indicated to be an effective method to evaluate myocardial microcirculation perfusion in patients with AMI following PCI. In addition, CSI, as a simple semi-quantitative index, may predict left ventricular function in patients with AMI.

Background The risk assessment of patients with stable chest pain (SCP) to defer further cardiovascular testing is crucial, but the most appropriate risk assessment strategy remains unknown. We aimed to compare current strategies to identify low risk SCP patients. Methods 5289 symptomatic patients who had undergone coronary artery calcium score (CACS) and coronary computed tomographic angiography scan were identified and followed. Pretest probability (PTP) of obstructive coronary artery disease (CAD) for every patient was estimated according to European Society of Cardiology (ESC)-PTP model and CACS-weighted clinical likelihood (CACS-CL) model, respectively. Based on the 2019 ESC guideline-determined risk assessment strategy (ESC strategy) and CACS-CL model-based risk assessment strategy (CACS-CL strategy), all patients were divided into low and high risk group, respectively. Area under receiver operating characteristic curve (AUC), integrated discrimination improvement (IDI) and net reclassification improvement (NRI) was used. Results CACS-CL model provided more robust estimation of PTP than ESC-PTP model did, with a larger AUC (0.838 versus 0.735, p < 0.0001), positive IDI (9%, p < 0.0001) and less discrepancy between observed and predicted probabilities. As a result, compared to ESC strategy which only applied CACS-CL model to patients with borderline ESC-PTP, CACS-CL strategy incorporating CACS with estimation of PTP to entire SCP patients indicated a positive NRI (19%, p < 0.0001) and a stronger association to major adverse cardiovascular events, with hazard ratios: 3.97 (95% confidence intervals: 2.75–5.72) versus 5.11 (95% confidence intervals: 3.40–7.69). Conclusion The additional use of CACS for all SCP patients in CACS-CL strategy improved the risk assessment of SCP patients to identify individuals at low risk.