Clinical impact of optical coherence tomography findings after drug-coated balloon treatment for patients with acute coronary syndromes

Drug-coated balloon (DCB) became a potential treatment option for patients with acute coronary syndrome (ACS); however, factors associated with target lesion failure (TLF) remain uncertain.This retrospective, multicentre, observational study included consecutive ACS patients who underwent optical coherence tomography (OCT)-guided DCB treatment. Patients were divided into two groups according to the occurrence of TLF, a composite of cardiac death, target vessel-related myocardial infarction, and ischemia-driven target lesion revascularisation.We enrolled 127 patients in this study. During the median follow-up period of 562 (IQR: 342-1164) days, 24 patients (18.9%) experienced TLF, and 103 patients (81.1%) did not. The cumulative 3-year incidence of TLF was 22.0%. The cumulative 3-year incidence of TLF was the lowest in patients with plaque erosion (PE) (7.5%), followed by those with rupture (PR) (26.1%) and calcified nodule (CN) (43.5%). Multivariable Cox regression analysis revealed that plaque morphology was independently associated with TLF on pre-PCI (percutaneous coronary intervention) OCT, and residual thrombus burden (TB) was positively associated with TLF on post-PCI OCT. Further stratification by post-PCI TB revealed a comparable incidence of TLF in patients with PR (4.2%) to that of PE if the culprit lesion had a smaller post-PCI TB than the cut-off value (8.4%). TLF incidence was high in patients with CN, regardless of TB size on post-PCI OCT.Plaque morphology was strongly associated with TLF for ACS patients after DCB treatment. Residual TB post-PCI might be a key determinant for TLF, especially in patients with PR.