Clinical characteristics of early and late drug-eluting stent in-stent restenosis and mid-term prognosis after repeated percutaneous coronary intervention.

BACKGROUND The mechanism and characteristics of early and late drug-eluting stent in-stent restenosis (DES-ISR) have not been fully clarified. Whether there are different outcomes among those patients being irrespective of their repeated treatments remain a knowledge gap. METHODS A total of 250 patients who underwent initial stent implantation in our hospital, and then were readmitted to receive treatment for the reason of recurrent significant DES-ISR in 2016 were involved. The patients were categorized as early ISR (<12 months; E-ISR; n = 32) and late ISR (≥12 months; L-ISR; n = 218). Associations between patient characteristics and clinical performance, as well as clinical outcomes after a repeated percutaneous coronary intervention (PCI) were evaluated. Primary composite endpoint of major adverse cardiac events (MACEs) included cardiac death, non-fatal myocardial infarction (MI), or target lesion revascularization (TLR). RESULTS Most baseline characteristics are similar in both groups, except for the period of ISR, initial pre-procedure thrombolysis in myocardial infarction, and some serum biochemical indicators. The incidence of MACE (37.5% vs. 5.5%; P < 0.001) and TLR (37.5% vs. 5.0%; P < 0.001) is higher in the E-ISR group. After multivariate analysis, E-ISR (odds ratio [OR], 13.267; [95% CI 4.984-35.311]; P < 0.001) and left ventricular systolic dysfunction (odds ratio [OR], 6.317; [95% CI 1.145-34.843]; P = 0.034) are the independent predictors for MACE among DES-ISR patients in the mid-term follow-up of 12 months. CONCLUSIONS Early ISR and left ventricular systolic dysfunction are associated with MACE during the mid-term follow-up period for DES-ISR patients. The results may benefit the risk stratification and secondary prevention for DES-ISR patients in clinical practice.