[Association between inflammation activity of left atrial epicardial adipose tissue measured by 18F-FDG PET/CT and atrial fibrillation]

Abstract

Objective: To explore the association between inflammation activity of left atrial epicardial adipose tissue (LA-EAT) measured by ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and atrial fibrillation (AF). Methods: A total of 78 patients with AF, who underwent ¹⁸F-FDG PET/CT in the Nuclear Medicine Department of the Third Affiliated Hospital of Soochow University due to abnormally elevated levels of tumor indicators or malignant tumors from March 2018 to December 2019, were enrolled in this retrospective study. According to the examination date of PET/CT and basic characteristics of AF patients (gender, age), a 1∶1 propensity score matching was used to enroll a non-AF control group (78 patients). The maximum standard uptake value of left atrial epicardial tissue (LA-EAT FDG SUV_max) and total EAT volume (V-EAT) were measured by ¹⁸F-FDG PET/CT. Left ventricular ejection fraction (LVEF) and left atrial diameter (LAD) were obtained by echocardiography. Blood lipids and biomarkers of inflammation were measured. The differences of clinical data and EAT-related indicators were compared between the AF group and control group. Logistic multivariate regression analysis was used to determine the related factors of AF. Then the receiver operating characteristic (ROC) curve was used to determine the cutoff value of LA-EAT FDG SUV_max on the diagnosis of AF. Univariate and multivariate logistic regression analysis were used to analyze the relationship between the increase of LA-EAT FDG SUV_max and AF. Results: The age was (66.9±10.2) years and there were 55 males (70.5%) in the AF group. The age was (66.9±8.0) years, and there were 52 males (66.7%) in the control group (both P>0.05). The LAD ((44.2±5.8) mm vs. (35.4±4.4) mm), V-EAT ((122.1±42.0) cm³ vs. (91.6±34.5) cm³), and LA-EAT FDG SUV_max ((1.6±0.3) vs. (1.4±0.2)) values were significantly higher, while LVEF ((60.1±4.7)% vs. (63.9±2.9)%) was lower in the AF group than in the control group (P all<0.001). Multivariate logistic regression analysis showed that LAD (OR=1.340, 95%CI 1.195-1.502), V-EAT (OR=1.016, 95%CI 1.001-1.031), and LA-EAT FDG SUV_max (OR=1.375, 95%CI 1.095-1.723) were positively correlated with AF, LVEF (OR=0.781, 95%CI 0.659-0.926) was negatively correlated with AF(P all<0.05). The area under the ROC curve of LA-EAT FDG SUV_max for diagnosis of AF was 0.680 (95%CI 0.597-0.764, P<0.001), and the best cut-off value was 1.415 with a sensitivity of 65.4% and specificity of 61.5%. After adjusting for high-density lipoprotein cholesterol, LVEF, LAD and V-EAT, LA-EAT FDG SUV_max≥1.415 was independently associated with AF (OR=2.982, 95%CI 1.122-7.926, P=0.010). Conclusions: The inflammatory activity of LA-EAT measured by ¹⁸F-FDG PET/CT is an independent risk factor of AF, and the increased inflammatory activity of LA-EAT is positively correlated with AF.