Intravascular ultrasound assessment of stent edge restenosis mechanisms and treatment outcomes following percutaneous coronary intervention

This study aimed to elucidate the biological or mechanical causes of stent edge restenosis (SER) via intravascular ultrasound (IVUS). A retrospective assessment was conducted on 126 SER lesions that underwent IVUS prior to revascularization. The primary mechanisms of SER were categorized. (1) neointimal hyperplasia (NIH); (2) neoatherosclerosis; (3) uncovered lesion; (4) stent underexpansion; or (5) a protruding calcified nodule (CN). The predominant biological or mechanical causes of SER were NIH in 42.9% (n = 54) of lesions, neoatherosclerosis in 32.5% (n = 41), uncovered lesion in 14.3% (n = 18), stent underexpansion in 7.9% (n = 10), and protruding CN in 2.4% (n = 3). The 2-year device-oriented clinical endpoints (DoCE) incidence was 7.1% (n = 9). The group with biological causes treated via drug-coated balloons (DCB) exhibited a comparable DoCE rate (9.5%) to those with biological causes treated with drug-eluting stents (DES) and mechanical causes managed with or without restenting (6.0%, HR 2.78, 95% CI: 0.91-9.21; p = 0.161). The majority of the analyzed SERs were attributed to biological causes, including NIH, neoatherosclerosis, and uncovered lesions. The 2-year DoCE rate within patients receiving DCB for mechanically or biologically induced SER was similar to that observed in patients receiving new DES.