99mTc-HFAPi SPECT Imaging Predicts Left Ventricular Remodeling After Acute Myocardial Infarction.

ABSTRACT

AIMS: This study aimed to evaluate the predictive utility of 99mTc-radiolabeled fibroblast activation protein inhibitor (99mTc-HFAPi) single-photon emission computed tomography (SPECT) imaging in post- acute myocardial infarction (AMI) patients for assessing 12-month left ventricular (LV) remodeling. METHODS: A cohort of 58 AMI patients (46 males, median age 61 [53, 67] years) underwent baseline 99mTc-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 99mTc-HFAPi and perfusion imaging, while 30 patients had follow-up echocardiography. Myocardial 99mTc-HFAPi activity was assessed at 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 99mTc-HFAPi uptake, exceeding perfusion defects. Baseline 99mTc-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 99mTc-HFAPi uptake extent and LV remodeling (OR= 2.14, 95%CI, 1.04, 4.39, p=0.038). CONCLUSIONS: 99mTc-HFAPi SPECT imaging holds promise in predicting LV remodeling post-MI, providing valuable insights for patient management and prognosis. LAY SUMMARY: Our study introduces 99mTc-radiolabeled fibroblast activation protein inhibitor (99mTc-HFAPi) single-photon emission computed tomography (SPECT) imaging as a potentially cost-effective modality for evaluating fibrotic process in the context of post-AMI LV remodeling. The study establishes a positive correlation between 99mTc-HFAPi activity, particularly 99mTc-HFAPi uptake extent, and LV remodeling, suggesting 99mTc-HFAPi SPECT imaging as a promising tool for risk prediction in post-AMI patients. The findings from this study have the potential to revolutionize post-AMI patient management by enabling early identification of those at risk for adverse LV remodeling. This identification could pave the way for tailored interventions, potentially improving clinical outcomes and reducing the development of heart failure.