Different neointimal pattern in early vs. late in-stent restenosis and clinical outcomes after drug-coated balloon angioplasty: An optical coherence tomography study

Background: There are few data of clinical outcomes after drug-coated balloon (DCB) angioplasty according to neointimal characteristics. This study investigated long-term clinical outcomes according to timing of in-stent restenosis (ISR) and neointimal characteristics in patients with drug-eluting stent (DES) ISR after DCB angioplasty. Methods and Results: In all, 122 patients (122 ISR lesions), treated with DCB under optical coherence tomography (OCT) examination before and after DCB, were categorized as early ISR (<12 months; E-ISR; n=21) and late ISR (≥12 months; L-ISR; n=101). Associations between OCT-based neointima characteristics and period of ISR, as well as clinical outcomes after DCB were evaluated. Major adverse cardiac events (MACE) were a composite of cardiac death, non-fatal myocardial infarction, or target lesion revascularization (TLR). Quantitative parameters of the neointima were similar, but qualitative characteristics showed significant differences between the E-ISR and L-ISR groups. The incidence of MACE (33.3% vs. 20.8%; P=0.069) and TLR (33.3% vs. 18.5%; P=0.040) was higher in the E-ISR group. In addition, the incidence of MACE was significantly higher for heterogeneous than non-heterogeneous neointima (43.7% vs. 19.6%; P=0.018), but was not significantly associated with neoatherosclerosis (33.4% vs. 18.4%; P=0.168). Conclusions: DCB angioplasty is less effective for heterogeneous neointima in DES ISR. OCT-based neointimal evaluation may be helpful in guiding treatment of DES ISR.