Clinical outcomes by optical characteristics of neointima and treatment modality in patients with coronary in-stent restenosis.

Aims First, to assess the relation between neointimal pattern and clinical outcomes following in-stent restenosis (ISR) treatment; second, to explore a potential interaction between neointimal pattern and treatment modality relative to clinical outcomes. Methods and results Based on the distribution of non-homogeneous quadrants, patients undergoing optical coherence tomography (OCT) prior to drug-eluting stent (DES) or drug-coated balloon (DCB) treatment of ISR, were categorized in low and high inhomogeneity groups (100 and 97 patients respectively). There were no significant differences in terms of MACE (P=0.939) or TLR (P=0.732). The exploratory analysis showed a significant interaction between neointimal pattern and treatment modality regarding MACE (P int =0.006) and TLR (P int =0.022). DES showed a significant advantage over DCB in the high [MACE: HR 0.26 (0.10-0.65), P=0.004; TLR: HR 0.28 (0.11-0.69), P=0.006], but not in the low inhomogeneity group (MACE: P=0.917; TLR: P=0.797). Conclusions In patients with ISR treated with DCB or DES, there were no significant differences in terms of MACE or TLR between low and high inhomogeneity groups. A significant interaction was observed between treatment modality and neointimal pattern with an advantage of DES over DCB in the high and no difference in the low inhomogeneity group. This warrants confirmation from prospective dedicated studies.