Percutaneous Coronary Intervention (PCI) is a widely used revascularization technique for patients with coronary artery disease. However, individuals with renal impairment exhibit significantly higher rates of procedural and post-procedural complications. This study evaluates complication rates of PCI across varying stages of renal dysfunction in patients undergoing emergency and elective angioplasty. A retrospective cohort of 842 patients was studied from 2020–2024, categorized based on estimated glomerular filtration rate (eGFR). Findings revealed that patients with severe renal impairment had higher incidences of contrast-induced nephropathy (CIN), in-stent thrombosis, periprocedural myocardial infarction, and mortality. The research recommends modified procedural dosing, use of iso-osmolar contrast agents, and post-procedure hydration protocols to improve clinical outcomes.