99m Tc-HFAPi SPECT imaging predicts left ventricular remodeling after acute myocardial infarction.

Background: Despite improved treatments for acute myocardial infarction (AMI), myocardial fibrosis remains a key driver of adverse left ventricular (LV) remodeling and increased mortality. Fibroblast activation and proliferation significantly contribute to this process by enhancing cardiac fibrosis, which can lead to detrimental changes in LV structure. This study evaluates the effectiveness of ^99m Tc-labeled fibroblast activation protein inhibitor ( ^99m Tc-HFAPi) SPECT imaging in predicting LV remodeling over 12 months in post-AMI patients.
Methods: A cohort of 58 AMI patients (46 males, median age 61 [53, 67] years) underwent baseline ^99m Tc-HFAPi imaging (5 ± 2 days post-MI), perfusion imaging (6 ± 2 days post-MI), and echocardiography (2 ± 2 days post-MI). Additionally, 15 patients had follow-up ^99m Tc-HFAPi and perfusion imaging, while 30 patients had follow-up echocardiography. Myocardial ^99m Tc-HFAPi activity was assessed at the patient level. LV remodeling was defined as a ≥10% increase in LV end-diastolic diameter (LVEDD) or LV end-systolic diameter (LVESD) from baseline to follow-up echocardiography.
Results: AMI patients displayed localized but non-uniform ^99m Tc-HFAPi uptake, exceeding perfusion defects. Baseline ^99m Tc-HFAPi activity exhibited significant correlations with BNPmax, LDHmax, cTNImax, and WBCmax, inversely correlating with LVEF. After 12 months, 11 patients (36.66%) experienced LV remodeling. Univariate regression analysis demonstrated an association between baseline ^99m Tc-HFAPi uptake extent and LV remodeling (OR = 2.14, 95%CI, 1.04, 4.39, P = 0.038).
Conclusions: ^99m Tc-HFAPi SPECT imaging holds promise in predicting LV remodeling post-MI, providing valuable insights for patient management and prognosis.
(Copyright © 2024 American Society of Nuclear Cardiology. Published by Elsevier Inc. All rights reserved.)