Peri-Procedural Clinical Characteristics and Short-Term Renal Outcomes of Metformin-Treated Patients with Type 2 Diabetes Mellitus Undergoing Coronary Angiography

Abstract

Background: Patients with type 2 diabetes mellitus (T2DM) frequently undergo coronary angiography because of their increased cardiovascular risk. Periprocedural management of metformin remains important because of concerns about renal safety, contrast-associated acute kidney injury (CA-AKI), and lactic acidosis. Objective: To describe the peri-procedural clinical characteristics and short-term renal outcomes of metformin-treated patients with T2DM undergoing coronary angiography and to examine the relationship between short-term serum creatinine change and selected clinical and procedural factors. Methods: This prospective observational study was conducted at Azadi Cardiac Centre, Kirkuk, Iraq, from May 2022 to May 2024. One hundred adults with T2DM receiving metformin and undergoing coronary angiography were enrolled. Baseline demographic, clinical, and laboratory data were recorded before the procedure. Patients continued metformin throughout the peri-procedural period, low-osmolality contrast medium was used, and serum creatinine was remeasured 72 hours later. Results: Hyperlipidemia (64%) and hypertension (55%) were the most common comorbidities. Mean serum creatinine increased slightly from 0.73±0.13mg/dL to 0.75±0.19mg/dL at 72 hours, but this change was not statistically significant (p=0.103). Only one patient developed post-procedural kidney injury and recovered with hydration and monitoring. No clinically evident lactic acidosis was observed. Creatinine change was not significantly associated with metformin dose, contrast volume, or left ventricular systolic function. Conclusions: Short-term renal function remained generally stable in metformin-treated patients with T2DM undergoing coronary angiography. These findings support a cautious, individualized approach to peri-procedural metformin management in lower-risk patients.