4 Renal function-based contrast dosing to define ‘prognostic’ contrast limits in patients undergoing coronary angioplasty

Background Renal function-based contrast dosing minimises renal injury following percutaneous coronary intervention (PCI). The ratio (R) of contrast volume:glomerular filtration rate (GFR) has been studied but its prognostic relevance is unknown. Aim To establish the relationship between R and mortality; and define a ‘prognostic’ threshold (RT) for contrast in PCI for stable disease, non ST-elevation ACS (NSTEACS) and ST-elevation ACS (STEACS). Method We evaluated 44 082 non-dialysis patients between 2008–2014. GFR was calculated using CG, CKD-EPI and MDRD equations. R was determined for each patient and its relationship with mortality was modelled mathematically and analysed using Cox regression and adjusted ROC curve analyses. Results Multivariable analyses identified R as an independent predictor of 3 year mortality (HR=1.03, 95% CI: 1.02 to 1.04, p Conclusion This study advocates a RT=7.7–8.3 for stable disease and RT=5.3–5.7 for NSTEACS/STEACS. This is greater than previously reported but implies greater contrast volumes may ultimately be tolerated in the contemporary PCI era.