Clinical implication of neointimal burden in in‐stent restenosis treated with drug‐coated balloon

Background Although drug‐coated balloon (DCB) angioplasty is a well‐established drug‐eluting stent (DES) in‐stent restenosis (ISR) strategy, there are minimal data regarding the association of neointimal burden on optical coherence tomography (OCT) before and after DCB and adverse clinical events. This study aimed to investigate the clinical impact of neointimal burden measured with OCT in patients with DES ISR after DCB angioplasty. Methods From 2010 through 2013, a total of 122 patients with 122 ISR lesions were treated with DCB, which was preceded and followed by OCT examination. Major adverse cardiac events (MACE, a composite occurrence of cardiovascular cardiac death, nonfatal myocardial infarction [MI], or target lesion revascularization [TLR]) were evaluated. Results MACE occurred in 27 patients (4 nonfatal MIs and 23 TLRs) during the follow‐up (median: 55.3 months, interquartile range 43.1–66.0). The mean lumen area was significantly smaller (3.21 ± 2.42 mm2 vs. 4.80 ± 2.53 mm2, p = .005) and the mean percentage of neointimal volume derived by OCT was greater (49.3 ± 9.2% vs. 38.3 ± 17.5%, p = .006) in patients with MACE before DCB angioplasty. The pre‐procedural mean percentage of neointimal volume (cut‐off 50%, area under the receiver operating characteristic [ROC] curve = 0.644, 95% confidence interval [CI] = 0.531–0.758, p = .022) and post‐procedural mean percentage of neointimal volume (cut‐off 25%, area under ROC curve = 0.659, 95% CI = 0.546–0.773, p = .012) were identified as significant parameters to predict MACE. Conclusion The OCT‐derived mean percentages of neointimal volume before and after DCB angioplasty can be important parameters for predicting future MACE in patients with DES ISR.