BACKGROUND Studies comparing the drug-eluting balloon (DEB) with contemporary drug-eluting stent (DES) in the treatment of in-stent restenosis (ISR) have been scarce. We compared that the efficacy and safety of contemporary DES versus DEB in unselected, real world patients of ISR occurred in bare-metal stent or DES.

METHODS Patient-level pooled analysis from nationwide multicenter registries was performed with 628 consecutive patients who underwent ISR treatment using 2nd or 3rd generation DES or DEB. Target lesion failure (TLF) and patient-oriented composite outcomes (POCO, composite of all-cause mortality, all-cause myocardial infarction, or any revascularization) at 1-year follow-up were compared between the DES and DEB groups.

RESULTS A total of 628 patients with 697 ISR lesions were treated using newer generation DES (n=409) or DEB (n=219). About 55.1% presented with acute coronary syndrome, and 15.1% showed left ventricular dysfunction. The risks of TLF and POCO were significantly lower in the DES group, even after being adjusted by an inverse probability weighted model (TLF, 9.2% vs. 17.9%, HR_adjust 0.22, 95% CI 0.11-0.47; POCO, 12.4% vs. 24.1%, HR_adjust 0.25, 95% CI 0.13-0.48, all p-values<0.001), mainly driven by the significantly lower risk of target lesion revascularization (TLR) (7.6% vs. 13.0%, HR_adjust 0.21, 95% CI 0.09-0.49, p<0.001). Treatment of ISR with DEB independently predicted TLF (HR 1.87, 95% CI 1.05-3.02, p=0.034) along with multi-vessel disease, chronic kidney disease, type B2 or C lesion, and number of treated lesion>1.

CONCLUSIONS In unselected patients of ISR, clinical outcome at one year was mainly dependent on difference in TLR and found to be better with contemporary DES than DEB.