18F-FAPI PET/CT imaging for identifying the involved myocardium in hypertrophic cardiomyopathy
10.3760/cma.j.cn321828-20240810-00290
- VernacularTitle:18F-FAPI PET/CT显像识别肥厚型心肌病受累心肌
- Author:
Li WANG
1
;
Yilu WANG
;
Yu ZHANG
;
Yao SU
;
Zhixiang DONG
;
Minfu YANG
Author Information
1. 首都医科大学附属北京朝阳医院核医学科,北京 100020
- Publication Type:Journal Article
- Keywords:
Cardiomyopathy, hypertrophic;
Fibroblasts;
Antagonists and inhibitors;
Positron-emission tomography;
Tomography, X-ray computed;
Magnetic resonance imaging
- From:
Chinese Journal of Nuclear Medicine and Molecular Imaging
2025;45(9):519-524
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the ability of 18F-fibroblast activation protein inhibitor (FAPI) PET/CT imaging to identify involved myocardium in patients with hypertrophic cardiomyopathy (HCM) compared with cardiac MRI. Methods:A prospective study was conducted on 50 patients (32 males, 18 females, age (43±13) years) with HCM confirmed by ultrasound or cardiac MRI in Beijing Chaoyang Hospital from July 2021 to January 2022. All patients underwent both cardiac 18F-FAPI PET/CT and MRI. The SUV max and maximum target-to-background ratio (TBR max) of the left ventricular myocardium were obtained using post-processing software. Regions with 18F-FAPI uptake not less than predefined thresholds (SUV max 40%, 50%, 60%) were defined as myocardium with positive uptake. The FAPI amount was defined as the product of TBR max and the extent of FAPI-positive uptake (FAPI%). Cardiac MRI post-processing software was used to measure the extent of left ventricular myocardial late gadolinium enhancement (LGE) (expressed as LGE%), native T 1 value, extracellular volume fraction (ECV), and myocardial deformation characteristics. Spearman rank correlation analysis was employed to assess the correlation between 18F-FAPI imaging parameters and cardiac MRI parameters, as well as the correlation between FAPI amount and the 5-year risk score for sudden cardiac death (SCD). Linear regression analysis was utilized to identify factors associated with FAPI amount. Results:When the threshold for 18F-FAPI-positive uptake in the left ventricular myocardium was set at 60%, the correlations between FAPI amount, FAPI%, and MRI parameters were optimal ( rs values: from -0.465 to 0.460, all P<0.05). Multivariate linear regression analysis revealed that HCM duration ( β=0.128, 95% CI: 0.022-0.233, P=0.008), serum N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels ( β=0.190, 95% CI: 0.099-0.280, P<0.001), and left ventricular ejection fraction ( β=-0.005, 95% CI: -0.011 to 0.000, P=0.041) were independent predictors of FAPI amount. FAPI amount was positively correlated with the 5-year SCD risk score across different thresholds (40%: rs=0.32, P=0.026; 50%: rs=0.29, P=0.039; 60%: rs=0.29, P=0.040). Conclusions:When the threshold for 18F-FAPI-positive uptake is set at 60%, 18F-FAPI PET/CT imaging can more effectively identify the involved myocardium in HCM. FAPI amount is correlated with the 5-year SCD risk score in patients with HCM.