Predictor of in-stent restenosis in patients with drug-eluting stent (PRIDE)- a retrospective cohort study.

BACKGROUND: It is a fact that coronary artery disease (CAD) is more prevalent in India as compared to western countries. The major risk factors associated with the early CAD are a high prevalence of diabetes mellitus, atherogenic lipid profile, smoking habits, sedentary lifestyle, low socioeconomic condition and high prevalence of obesity. Is this true for restenosis after drug-eluting stent (DES) implantation and factors associated with it? The main objective of the study was to determine the rate of in-stent restenosis (ISR) in patients with DES and risk factors associated with it from our region. METHODS: It was a single-center, retrospective cohort study in which 550 patients who underwent DES implantation were included. Patient's demographic data, coronary angiography findings, procedural characteristics and development of ISR were noted. RESULTS: Out of 550 patients, 31 developed ISR with a rate of restenosis of 5.63% and target lesion revascularization (TLR) of 5.63%. On multiple Cox-regression analysis, only diabetes mellitus (DM) (p=0.008, adjusted hazard ratio (HR): 2.757, 95% confidence interval (CI): 1.296-5.863), deployment of stent in the left anterior descending (LAD) artery (p=0.031, adjusted HR: 3.342, 95% CI: 1.115-10.017) and periprocedural complication during percutaneous coronary intervention (p=0.040, adjusted HR: 2.824, 95% CI: 1.049-7.603) were found to be significantly associated with increased risk of ISR. Kaplan-Meier survival analysis of event-free survival for restenosis showed patients with DM had significantly lower event-free survival compared to patients without DM (p=0.005 by log-rank test). CONCLUSIONS: In our study, the rate of restenosis after DES implantation was 5.63%. The presence of DM, the stent in the LAD territory and the periprocedural complication is strongly associated with the development of ISR......