Cardiac fibrosis: The Impact of Molecular Imaging of Fibroblast Activation Protein
State-of-the-art molecular imaging using Fibroblast Activation Protein (FAP)-targeted PET tracers enables non-invasive visualization of fibroblast activation. Early targeting of fibrosis is crucial because fibroblast activation precedes irreversible organ damage. Given that fibrotic diseases account for ~45% of deaths in industrialized countries, early detection supports timely intervention, therapy monitoring, and prevention of progressive cardiac.
In two of our recent studies in collaboration with Department of Biomedical Imaging and Image-Guided Therapy, Division of Nuclear Medicine and Division of Cardiology, Department of Internal Medicine II, Medical University of Vienna, Vienna, Austria, we demonstrate the utility of FAP-targeted imaging for assessing adverse cardiac remodeling in preclinical models of pressure overload-induced hypertrophy (diffuse interstitial fibrosis) and myocardial infarction (replacement fibrosis), delineating the temporal dynamics of fibrosis in both contexts. In clinical follow up study, myocardial [68Ga]Ga-FAPI may serve a time-robust index of active fibroblast signaling that relates to myocardial hemodynamic stress and stratifies one-year clinical response after Transcatheter Aortic Valve Implantation (TAVI) procedure.
Cardiac FAP imaging may provide precise fibrosis mapping, monitors remodeling dynamics, and predicts clinical outcomes.
DOI: 10.3390/ph18050658 and
DOI: 10.1007/s00259-026-07815-4
![Representative human cardiac images: PET/CT images performed 120 min after i.v. tracer injection. Enhanced [68Ga]Ga-DATA5m.SA.FAPi uptake is observed in the mid-distal anterior LV segments in axial (left), coronal (middle), and sagittal (right) views (blue arrows) – source https://www.mdpi.com/1424-8247/18/5/658](https://cardio.lbg.ac.at/wp-content/uploads/sites/14/2026/02/news-cardiac-fibrosis.png)