Contrast-induced acute kidney injury (CIAKI) is a common and serious complication of coronary angiography, caused by iodinated contrast agents. It significantly worsens cardiovascular prognosis and increases in-hospital morbidity and mortality.

This study aimed to uncover predictive factors of CIAKI and to investigate the contribution of pre-existing endothelial dysfunction to its onset following percutaneous coronary interventions (PCI). Preventive strategies with potential clinical relevance were concurrently evaluated.

This was a prospective observational longitudinal study in which we enrolled 187 patients with an indication for coronary angiography. Patients underwent an assessment of renal function: (basal creatinine, 24 h, 48–72 h and 1month after administration of contrast medium), we focused then on the evaluation of endothelial quality index (EQI) by finger thermal monitoring with E4 diagnosis Polymath (Fig. 1).

187 patients (134 males), mean age 61.1 ± 11.8 years, were enrolled; 56.7% were type 2 diabetics. CIAKI occurred in 60 patients (33.7%). Mean EQI was 0.86 ± 0.61. A vast majority (95.2%) had endothelial dysfunction (EQI < 2), and 75.9% had severe dysfunction (EQI < 1). CIAKI was significantly associated with severe endothelial dysfunction (P = 0.007), rescue PCI (P = 0.002), contrast volume > 100 ml (P = 0.015), and two-vessel coronary artery disease (P = 0.008). Multivariate analysis confirmed severe endothelial dysfunction, rescue PCI, and contrast volume ≥ 140 ml as independent risk factors. CIAKI was significantly less frequent in patients receiving pre-/post-hydration with isotonic saline or those under baseline statin therapy (P = 0.007 and P = 0.008, respectively).

This study demonstrates a significant association between severe endothelial dysfunction assessed non-invasively by FTM and the risk of CIAKI. These findings highlight the potential of EQI as a novel, low-cost, reproducible predictor of CIAKI, with promising implications for cardiovascular risk stratification and prevention in interventional cardiology.