Neointima characteristics as a prognostic marker for drug-coated balloon angioplasty in patients with in-stent restenosis: an optical coherence tomography study

Background Research has shown that the prognosis of in-stent restenosis (ISR) lesions after drug-coated balloon (DCB) angioplasty can differ in relation to in-stent neointimal characteristics. However, changes in neointima characteristics after DCB have not been studied. This study sought to investigate changes in neointima characteristics after DCB for ISR. Methods From the Yonsei Optical Coherence Tomography (OCT) registry, data on DCBs performed in patients with ISR were collected. Neointima characteristics were categorized as homogeneous, heterogeneous, layered neointima, and neoatherosclerosis in each OCT procedure. Homogeneous and layered neointima were classified as a favorable neointima, while heterogeneous neointima and neoatherosclerosis were classified as an unfavorable neointima. The data of 67 ISR patients were analyzed. Results The median duration between initial and follow-up OCT was 9.6 months. Patients with homogeneous and layered neointima on the initial OCT before DCB mostly appeared as homogeneous (66.7 and 68.2%, respectively) on the follow-up OCT, whereas most of the patients with heterogeneous neointima on the initial OCT remained unaltered (70%). Patients with unfavorable neointima at either the initial (P = 0.023) or the follow-up OCT (P = 0.037) had a worse major adverse cardiovascular event-free survival than the other patients. Patients who showed unfavorable neointima at both the initial and the follow-up OCT had the worst event-free survival (P = 0.038). Conclusions The follow-up OCT neointimal characteristics after DCB for ISR was associated with initial OCT characteristics. Sustained unfavorable neointima in serial OCT imaging may reflect poor prognosis in patients with ISR treated with DCB.