Chen Bi-Xi, Hu Huimin, Gong Juanni, Xi Xiao-Ying, Ma Yaning, Yang Yuanhua, Yang Min-Fu, Li Yidan
Department of Nuclear Medicine, Beijing Institute of Respiratory Medicine, Beijing Chao-Yang Hospital, Capital Medical University, 8th Gongtinanlu Rd, Chaoyang District, Beijing, 100020, China.
Department of Department of Echocardiography, Beijing Institute of Respiratory Medicine, Beijing Chao-Yang Hospital, Capital Medical University, 8th Gongtinanlu Rd, Chaoyang District, Beijing, 100020, China.
BMC Med Imaging. 2025 Mar 3;25(1):68. doi: 10.1186/s12880-025-01592-6.
This retrospective study was designed to explore the relationship between right ventricular fibroblast activation measured by fibroblast activation protein inhibitor (FAPI) imaging and myocardial deformation measured by Speckle‑tracking Echocardiography (STE) in patients with pulmonary hypertension (PH).
Clinical data of PH patients were collected [15 chronic thromboembolic pulmonary hypertension (CTEPH), 4 PAH, 1 PH with unclear and/or multifactorial mechanisms]. All of patients underwent FAPI imaging and echocardiography within one month. FAPI activity of right ventricle higher than that in the blood pool was defined as abnormal. The global and segmental maximum standardised uptake values (SUV) of the right ventricle were measured and further expressed as target-to-background ratio (TBR) with blood pool activity as background. right ventricular global longitudinal strain (RVGLS) and right ventricular free wall longitudinal strain (RVFWLS) including the basal-, mid-, and apical-segments were measured by STE.
Eighteen patients with PH showed abnormal FAPI uptake in right ventricle. No significant differences were found between CTEPH and other types of PH. TBR of right ventricle had negative correlations with RVGLS (r = -0.597, P = 0.005) and RVFWLS (r = -0.586, P = 0.007) at global level. While, at regional level, significant correlation was only demonstrated between TBR of right ventricle free wall and RVFWLS in apical region (r = -0.530, P = 0.016) and middle region (r = -0.457, P = 0.043). Among the traditional Echocardiography parameters, TBR of right ventricle were positively associated with thickness of right ventricular anterior wall (RVAW) (r = 0.475, P = 0.034), and inversely with right ventricular systolic function [RVFAC (r = -0.586, P = 0.007) and TAPSE (r = -0.565, P = 0.009)].
FAPI imaging can partially reflect the right ventricular strain reduction in patients with PH.
本回顾性研究旨在探讨在肺动脉高压（PH）患者中，通过成纤维细胞活化蛋白抑制剂（FAPI）成像测量的右心室成纤维细胞活化与通过斑点追踪超声心动图（STE）测量的心肌变形之间的关系。
收集PH患者的临床资料[15例慢性血栓栓塞性肺动脉高压（CTEPH）、4例肺动脉高压（PAH）、1例机制不明和/或多因素的PH]。所有患者在1个月内接受了FAPI成像和超声心动图检查。右心室FAPI活性高于血池定义为异常。测量右心室的整体和节段最大标准化摄取值（SUV），并以血池活性为背景进一步表示为靶本比（TBR）。通过STE测量右心室整体纵向应变（RVGLS）和右心室游离壁纵向应变（RVFWLS），包括基底段、中段和心尖段。
18例PH患者右心室FAPI摄取异常。CTEPH与其他类型的PH之间未发现显著差异。在整体水平上，右心室TBR与RVGLS（r = -0.597，P = 0.005）和RVFWLS（r = -0.586，P = 0.007）呈负相关。而在区域水平上，仅在心尖区（r = -0.530，P = 0.016）和中区（r = -0.457，P = 0.043）右心室游离壁TBR与RVFWLS之间显示出显著相关性。在传统超声心动图参数中，右心室TBR与右心室前壁厚度（RVAW）呈正相关（r = 0.475，P = 0.034），与右心室收缩功能呈负相关[右心室面积变化分数（RVFAC，r = -0.586，P = 0.007）和三尖瓣环平面收缩期位移（TAPSE，r = -0.565，P = 0.009）]。
FAPI成像可部分反映PH患者右心室应变降低情况。
