Background: Although drug-eluting balloon (DEB) is an effective strategy for in-stent restenosis (ISR) after coronary stenting, the relationship between the timing of ISR and the effect of DEB has not been well validated. Therefore, the aim was to investigate an efficacy of DEB according to the timing of ISR after DES implantation.
Methods: A total of 117 patients with DES ISR were treated with DEB and performed an optical coherence tomography (OCT) before and after DEB angioplasty. Early and late ISR were defined as <1 year and > 1 year after stenting. Early restenosis (<1 year: E-ISR) patients were 21. Late restenosis (1-3 years: L-ISR) patients and very late restenosis (>3 years: VL-ISR) patients were 38 and 58 respectively. The quantitative and qualitative optical coherence tomography (OCT) analysis was performed.
Results: Over a mean follow-up period of 17.8 ± 10.9 months, 19 repeated revascularization was occurred [7/21 in early ISR group, 12/96 (12.5%) in late ISR group]. The Kaplan-Meier estimated repeated revascularization rate was higher in early ISR group compared late ISR group (33.3% vs. 12.5%, p=0.044). Although there were no significant differences in quantitative preprocedural and postprocedural OCT findings between 2 groups, late ISR group showed more cholesterol crystal (33.3% vs. 4.8%, p=0.008), macrophage (31.3% vs. 0%, p=0.003), thin-cap fibroatheroma (27.1% vs. 0%, p=0.004) and neoatherosclerosis (32.3% vs. 4.8%, p=0.01) compared to early ISR group.
Conclusion: DEB is more efficient to prevent a repeated revascularization in late ISR than early ISR. The OCT examination may give more information and be helpful to expain the difference of qualitative neointimal characteristics according to the timing of ISR.
Figure 1. Comparison of target lesion revascularization free survival rate between early restenosis group and late, very late restenosis group.