Objectives: To assess, whether cardiac catheterization via radial access prevents contrast-induced nephropathy.

Background: Contrast-induced nephropathy (CIN) is a major clinical problem which accounts for more than 10% of acute kidney injury cases in hospitalized patients. Protective measures such as the infusion of isotonic saline solution or acetylcysteine have not consistently been proven to prevent acute kidney injury (AKI). However, there is growing evidence that radial access for coronary angiography and coronary intervention is associated with a lower incidence of AKI compared to femoral access.

Methods and results: In a retrospective monocentric analysis, 2937 patients that had undergone cardiac catheterization were examined. Up to 2013, coronary intervention was performed primarily via the femoral artery in our hospital; thereafter, interventions were primarily done via the radial artery. In the cohort under study, 1141 patients had received catheterization using the radial access while 1796 were examined via the femoral artery. No significant differences were found in the two groups regarding the amount of iodinated contrast medium applied [femoral group: 180 (120-260) ml; radial group: 180 (120-250) ml; P = 0.438]. A total of 400 (13.6%) patients developed acute kidney injury (AKI) after cardiac catheterization (85.3% AKI stage 1; 12.8% AKI stage 2; 2% AKI stage 3). AKI was significantly less frequent in patients that had received radial access compared to patients with femoral access (10.1 vs. 15.9%, P < 0.001). Multivariate regression analysis showed that patient age (1.03/year; 95% CI 1.02-1.04/year; P < 0.001), the amount of contrast media applied (OR 1.003/ml; 95% CI 1.002-1.004/ml; P < 0.001), acute coronary syndrome (OR 2.01, 95% CI 1.52-2.66; P < 0.001), CKD (OR 1.62, 95% CI 1.50-1.70; P < 0.001), pre-existing heart failure (OR 1.27, 95% CI 1.00-1.42 P = 0.007), previous myocardial infarction (OR 1.34, 95% CI 1.15-1.49; P = 0.001), diabetes (OR 1.25, 95% CI 1.04-1.41; P = 0.020) and serum creatinine before the procedure (1.45/mg/dl; 95% CI 1.24-1.69/mg/dl; P < 0.001) were important risk factors for the occurrence of AKI. Our analysis points to a significant risk reduction using radial access (OR 0.65; 95% CI 0.51-0.83; P < 0.001). Interestingly, this reduction in risk was also evident in patients with CKD (OR 0.59; 95% CI 0.41-0.87; P = 0.007). The superiority of radial access was particularly obvious in the subgroup of patients with acute coronary syndrome (13.1% AKI in the radial access group vs. 23.6% AKI in the femoral access group, OR 0.52; 95% CI 0.34-0.81; P = 0.003).

Conclusion: Our study shows that cardiac catheterization using radial access bears significantly lower risk of AKI than cardiac catheterization via femoral access. The advantage of radial access in acute coronary syndrome regarding morbidity and mortality could partly be explained by the here demonstrated reduced risk for AKI. Thus, radial access should be preferred in patients at risk for AKI.