18 F-FAPI Outperforms 18 F-FDG PET/CT in Detecting Focal Inflammation as a Cause of Refractory In-Stent Restenosis : A Case Report

Clin Nucl Med. 2026 Aug 1;51(8):742-743. doi: 10.1097/RLU.0000000000006563. Epub 2026 May 29.

Abstract

Inflammation-associated coronary artery disease (I-CAD) is a recognized yet underdiagnosed cause of refractory in-stent restenosis. Conventional imaging modalities often lack sensitivity for detecting focal inflammatory activity. A 74-year-old woman with recurrent ISR was admitted to our institution. Dual-tracer ¹⁸F-FAPI and ¹⁸F-FDG PET/CT revealed locally increased radiotracer uptake within the left anterior descending artery (LAD) stent segment, with more intense uptake on 18 F-FAPI than on 18 F-FDG. We present the dual-tracer PET/CT findings in this patient with recurrent in-stent restenosis, suggesting active peri-stent fibroblast-related remodeling and an inflammation-associated mechanism. The patient was subsequently managed with anti-inflammatory therapy rather than repeated revascularization.

Keywords: 18F-FAPI PET/CT; 18F-FDG PET/CT; inflammation-associated coronary artery disease; refractory in-stent restenosis.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Coronary Restenosis* / diagnostic imaging
  • Coronary Restenosis* / etiology
  • Female
  • Fibroblast Activation Protein Alpha
  • Fluorodeoxyglucose F18*
  • Humans
  • Inflammation* / complications
  • Inflammation* / diagnostic imaging
  • Positron Emission Tomography Computed Tomography*
  • Serine Endopeptidases*
  • Stents* / adverse effects

Substances

  • Fluorodeoxyglucose F18
  • Fibroblast Activation Protein Alpha
  • Serine Endopeptidases