Contrast induced nephropathy in older Vietnamese patients undergoing coronary angiography and intervention

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. Background The prevalence of coronary heart disease increases with age and older people accounted for a large proportion of patients presenting with coronary heart disease. Advancement in percutaneous coronary intervention (PCI) has contributed to reduced mortality in patients with coronary artery disease. However, coronary angiography and percutaneous intervention have also increased the risk of developing contrast induced nephropathy (CIN), especially in older patients. More than ten risk assessment tools have been developed to predict CIN. Among these, the Mehran risk score has been the most commonly used in Vietnam. In recent years, new simple risk prediction models have been proposed, including the contrast volume-to-glomerular filtration rate ratio (CV/GFR ratio). The CV/GFR ratio is calculated as the ratio of contrast medium quantity to glomerular filtration rate. Purpose The aim of this study was to (1) examine the incidence of CIN in a cohort of older patients undergoing coronary angiography and/or PCI at a tertiary hospital in Vietnam, (2) compare the validity of the CV/GFR ratio and the Mehran score in predicting CIN, and (3) to identify optimal cut-off points of these scales by which can help identify older patients with high risk of developing CIN in this population. Methods A prospective observational study was conducted in patients aged ≥ 60 years at a tertiary hospital in Vietnam from September 2019 to May 2020. CIN was defined as 25% increase in serum creatinine from baseline or 0.5mg/dL absolute increase in serum creatinine occurring within 48 hours post IV contrast administration. The CV/GFR ratio and the Mehran score were applied for predicting risk of CIN. Previous studies suggest Mehran score >5 or CV/GFR ratio >3.7 as a predictor of an early abnormal increase in serum creatinine after PCI. Receiver Operator Characteristic (ROC) was applied to evaluate area under the curve (AUC) of the CV/GFR ratio and Mehran score in predicting CIN, and the sensitivity, specificity for common cut-off points that were suggested in previous studies. Results A total of 170 participants were included in this study. They had a mean age of 70 years, 33.1% were women. The incidence of CIN was 9.4%. Participants with CIN had higher prevalence of chronic kidney disease, heart failure and anaemia at admission. The AUC of the CV/GFR ratio against CIN was 0.79 (95%CI 0.65-0.92), and of the Mehran score against CIN was 0.65 (95%CI 0.51-0.82) (Figure 1). The sensitivity and specificity for common cut-off points of the CV/GFR ratio and Mehran score are presented in Figure 2. Conclusions Our study found that CIN was common in older patients after PCI. Both CV/GFR ratio and Mehran score had good diagnostic value for predicting CIN in the study participants.