Abstract
A BSTRACT Restenosis after percutaneous coronary intervention remains a clinically relevant form of stent failure despite substantial improvements in drug-eluting stent technology, implantation technique, and secondary prevention. Its development reflects the interaction of mechanical and procedural factors, including stent underexpansion, calcified lesions, stent fracture, malapposition, geographic miss, and inadequate lesion preparation, and biological mechanisms such as endothelial injury, inflammation, vascular smooth muscle cell proliferation, neointimal hyperplasia, and neoatherosclerosis. This narrative review summarizes current insights into the molecular mechanisms, clinical predictors, and biomarkers of restenosis, as well as the potential integration of these findings with intravascular imaging data. Particular emphasis is placed on endothelial and inflammatory biomarkers that reflect the activation of key pathophysiological pathways and may support early risk stratification in selected patients. However, most biomarkers discussed remain investigational and are not yet validated for routine clinical decision-making. Optical coherence tomography and intravascular ultrasound enable detailed morphological assessment of the lesion and identification of the underlying cause of restenosis. Integration of laboratory and imaging parameters may support personalized strategies for early detection, precise diagnosis, and individualized treatment of restenosis. At present, however, this approach should be regarded as complementary to established clinical and imaging-based assessment.