Evaluation of Pericoronary Fat Attenuation Index to Better Identify Culprit Lesions in Acute Coronary Syndrome According to Stenosis Severity.

Li L ，Tang J ，Fang P ，Sun Y ，Gao Y ，Qi H ，Liu B ，Zhang J ，Fan L ... -  《-》

The predictive value of lesion-specific pericoronary fat attenuation index for major adverse cardiovascular events in patients with type 2 diabetes.

The purpose of this study was to explore the prognostic significance of the lesion-specific pericoronary fat attenuation index (FAI) in forecasting major adverse cardiovascular events (MACE) among patients with type 2 diabetes mellitus (T2DM). This study conducted a retrospective analysis of 304 patients diagnosed with T2DM who underwent coronary computed tomography angiography (CCTA) in our hospital from December 2011 to October 2021. All participants were followed for a period exceeding three years. Detailed clinical data and CCTA imaging features were carefully recorded, encompassing lesion-specific pericoronary FAI, FAI of the three prime coronary arteries, features of high-risk plaques, and the coronary artery calcium score (CACS). The MACE included in the study comprised cardiac death, acute coronary syndrome (which encompasses unstable angina pectoris and myocardial infarction), late-phase coronary revascularization procedures, and hospital admissions prompted by heart failure. Within the three-year follow-up, 76 patients with T2DM suffered from MACE. The lesion-specific pericoronary FAI in patients who experienced MACE was notably higher compared to those without MACE (-84.87 ± 11.36 Hounsfield Units (HU) vs. -88.65 ± 11.89 HU, p = 0.016). Multivariate Cox regression analysis revealed that CACS ≥ 100 (hazard ratio [HR] = 4.071, 95% confidence interval [CI] 2.157-7.683, p < 0.001) and lesion-specific pericoronary FAI higher than - 83.5 HU (HR = 2.400, 95% CI 1.399-4.120, p = 0.001) were independently associated with heightened risk of MACE in patients with T2DM over a three-year period. Kaplan-Meier analysis showed that patients with higher lesion-specific pericoronary FAI were more likely to develop MACE (p = 0.0023). Additionally, lesions characterized by higher lesion-specific pericoronary FAI values were found to have a greater proportion of high-risk plaques (p = 0.015). Subgroup analysis indicated that lesion-specific pericoronary FAI higher than - 83.5 HU (HR = 2.017, 95% CI 1.143-3.559, p = 0.015) was independently correlated with MACE in patients with T2DM who have moderate to severe coronary calcification. Moreover, the combination of CACS ≥ 100 and lesion-specific pericoronary FAI>-83.5 HU significantly enhanced the predictive value of MACE in patients with T2DM within 3 years. The elevated lesion-specific pericoronary FAI emerged as an independent prognostic factor for MACE in patients with T2DM, inclusive of those with moderate to severe coronary artery calcification. Incorporating lesion-specific pericoronary FAI with the CACS provided incremental predictive power for MACE in patients with T2DM.

Liu M ，Zhen Y ，Shang J ，Dang Y ，Zhang Q ，Ni W ，Qiao Y ，Hou Y ... -  《Cardiovascular Diabetology》

Correlation between hemodynamics assessed by FAI combined with CT-FFR and plaque characteristics in coronary artery stenosis.

While both CT-FFR and FAI are found to be associated with the development of CAD, their relationship with hemodynamics and plaque characteristics remains unclear. The present study aims to investigate the relationship between hemodynamics assessed by FAI combined with CT-FFR and plaque characteristics in functionally significant coronary artery stenosis. This retrospective study included 130 patients with suspected coronary heart disease, who were admitted to the Department of Cardiology of our hospital and underwent coronary computed tomography angiography (CCTA) from January 2022 to December 2023. Clinical baseline data and relevant auxiliary examination results were collected, and CCTA, FAI, and CT-FFR data were analyzed to investigate the relationship between these imaging parameters and both the hemodynamics and plaque characteristics of coronary artery lesions. From 130 patients, a total of 207 diseased vessels were analyzed and classified based on CAD-RADS grading: 128 vessels exhibited stenosis of less than 50%, and 79 exhibited stenosis exceeding 50%. Patients with more than one lesion of > 50% stenosis were classified into the myocardial ischemia group (44 cases), and the rest were categorized as the non-myocardial ischemia group (86 cases). Compared to the non-myocardial ischemia group, patients in the myocardial ischemia group were significantly older (p < 0.001). No significant difference was found between the two groups in sex, cardiovascular risk factors, or the indicator of stenotic vessel distribution. The minimum CT-FFR in vessels with < 50% stenosis was higher than in vessels with > 50% stenosis, ΔCT-FFR was lower in vessels with < 50% stenosis than in vessels with > 50% stenosis, and the median CT-FFR was significantly lower in vessels with > 50% stenosis than in vessels with < 50% stenosis (p < 0.001). Additionally, FAI-LAD, FAI-LCX, FAI-RCA, and FAI-Mean were found to be significantly higher in vessels with > 50% stenosis compared to vessels with < 50% stenosis (p < 0.05). A negative correlation was observed between the minimum CT-FFR among three main coronary arteries (LAD, LCX, RCA) and CAD-RADS classification, while both ΔCT-FFR and FAI were positively correlated with CAD-RADS classification (p < 0.05). Non-calcified plaques were more prevalent in the vessels with > 50% stenosis, primarily located in the LAD, while calcified plaques were predominantly observed in vessels with < 50% stenosis (p < 0.001). In addition, in vessels with > 50% stenosis, plaques were longer, the degree of luminal stenosis was greater, and both the total volume and burden of plaques were significantly greater than in vessels with < 50% stenosis (p < 0.001). Lastly, the FAIlesion value in the vessels with > 50% stenosis was higher than in vessels with < 50% stenosis (p < 0.001). FAI is associated with coronary artery stenosis and myocardial ischemia, and may serve as a novel indicator for identifying myocardial ischemia. Both FAI and CT-FFR demonstrated strong predictive abilities in significant coronary stenosis.

Duan B ，Deng S ，Xu R ，Wang Y ，He K ... -  《BMC MEDICAL IMAGING》

Quantitative plaque characterization, pericoronary fat attenuation index, and fractional flow reserve: a novel method for differentiating between stable and unstable angina pectoris in a case-control study.

Accurate diagnosis of coronary artery disease is essential for preventing serious cardiovascular events. Although coronary computed tomography angiography (CCTA) is widely used in the clinic, it is limited because it only provides anatomical information, which makes differentiating in-depth between subtypes of noncalcified plaques and assessing the inflammatory state of coronary vessels difficult. Fractional flow reserve with computed tomography (FFR-CT) can be combined with CCTA to form a hybrid anatomic-physiologic diagnostic strategy. This study aimed to improve the recognition of stable and unstable angina with quantitative plaque characteristics, fat attenuation index (FAI), and fractional flow reserve with FFR-CT using a coronary artificial intelligence (AI)-assisted diagnostic system. In this retrospective case-control study, 215 and 202 patients with stable and unstable angina pectoris, respectively, who were treated at our hospital between January 2015 and August 2023, were enrolled. Propensity score matching was used to reduce clinical baseline data bias. Binary logistic regression was used to determine the risk factors for unstable angina pectoris. The diagnostic efficacy of quantitative plaque characteristics, pericoronary FAI, FFR-CT, and their combined models in differentiating stable and unstable angina pectoris was determined using the area under the receiver operating characteristic (ROC) curve. This study included 168 pairs of patients with stable or unstable angina. Patients with unstable angina had a significantly greater pericoronary FAI volume and percentage of, lipid, and fibrolipid components within the total plaque (all P<0.001) and a significantly smaller percentage of calcification components (P<0.001), FFR-CT (P=0.003), and lumen area at the narrowest point of the stenosis(P=0.003) than those with stable angina. Independent risk factors for unstable angina were FAI >-82 Hounsfield units (HU) and total intraplaque lipid component percentage >1.2% (P=0.003 and 0.009, respectively). The area under the curve (AUC) of the ROC regarding pericoronary FAI differentiating between stable and unstable angina was 0.631 (P<0.001). In contrast, the AUC of the combined model of FFR-CT, plaque characteristics, and pericoronary FAI was 0.698 (P<0.001). The AUC value of the combined model was significantly higher than that of the diagnostic model using a single index (all, P<0.001). AI-assisted diagnostic systems could provide new methods to differentiate between stable and unstable angina. Patients with FAI >-82 HU and total intraplaque lipid component percentage >1.2% had a significantly increased risk of unstable angina, a finding that may be informative for clinical decision-making.

Li D ，Guan H ，Wang Y ，Zhu T ... -  《-》

Predictive value of pericoronary fat attenuation index for graft occlusion after coronary artery bypass grafting.

Based on coronary computed tomography angiography (CCTA), this study aimed to evaluate the predictive value of pericoronary fat attenuation index (FAI) for graft occlusion in patients following coronary artery bypass grafting (CABG). The clinical and imaging data of 100 patients with coronary artery disease (CAD) who underwent CCTA and subsequently received successful CABG between December 2012 and March 2024 were retrospectively collected. According to the subsequent CCTA evaluation of grafts, they were categorized into occlusion group (n = 27) and patency group (n = 73). Based on CCTA images, FAI of the proximal segment of the three coronary arteries and epicardial adipose tissue (EAT) parameters were measured and compared between the two groups. The Cox regression model was employed to screen the independent predictors of graft occlusion. The predictive model was constructed, and the receiver operating characteristic (ROC) curve was drawn to evaluate the diagnostic performance of the model. Among the 100 cases, 74 were males, with a mean age was 62.42 ± 7.57 years. During the 15.50 (5.00, 36.75) months follow-up period, grafting vessel occlusion occurred in 27 patients (27.0%). The right coronary artery (RCA) in occlusion group was -73.36 ± 7.24HU, which was notably higher compared to patency group (-79.93 ± 9.75HU) (P < 0.05). Multivariable Cox regression analysis indicated that RCA FAI (HR = 5.205, 95% CI 1.938-13.979; P = 0.001) was independently correlated with graft occlusion, with an optimal cutoff value of -79.39 HU.RCA FAI added incremental prognostic value beyond clinical characteristics for patients following CABG (AUC 0.784 vs. 0.677, P = 0.027). The RCA FAI can serve as a crucial predictor for graft occlusion in patients following CABG, enabling early identification of high-risk individuals and facilitating timely and effective intervention measures to enhance patient prognosis.

Huang S ，Yu X ，Yang B ，Xu T ，Gu H ，Wang X ... -  《-》