3 Year Clinical Outcome Analysis and Failure Predictors in the Use of Intracoronary Brachytherapy for Drug-Eluting Stent Restenosis In-stent restenosis (ISR) has been one of the greatest obstacles standing in the way of long term patency in percutaneous coronary interventions. However, the use of drug eluting stents (DES) and their development has helped reduce ISR…