Background— Cystatin C (CyC) is more sensitive than serum creatinine (sCr) to rapidly detect acute changes in renal function. Methods and Results— We measured CyC together with sCr in 410 consecutive patients with chronic kidney disease undergoing either coronary and/or peripheral angiography and/or angioplasty. sCr was assessed at baseline and 24 and 48 hours after contrast media exposure. CyC was assessed at baseline and at 24 hours. Major adverse events (including death of any cause and dialysis) at 12 months were assessed. At 48 hours after contrast media exposure, contrast-induced acute kidney injury (defined as a sCr increase ≥0.3 mg/dL) occurred in 34 patients (8.2%). A CyC increase concentration ≥10% at 24 hours after contrast media exposure was detected in 87 patients (21.2%). This was the best CyC cutoff for the early identification of patients at risk for contrast-induced acute kidney injury (negative predictive value=100%; positive predictive value=39.1%). According to the defined cutoffs (that is, increase in CyC ≥10% and sCr ≥0.3 mg/dL), major adverse events occurred in 16 of 297 patients (5.4%) without any cutoffs satisfied (group 1), in 9 of 49 patients (18.4%) with only a CyC increase ≥10% (group 2), and in 9 of 31 patients (29%) with both cutoffs satisfied (group 3). By logistic regression analysis, the independent predictors of major adverse events at 1 year were group 2 (odds ratio=2.52; 95% confidence interval, 1.17 to 5.41; P =0.02), group 3 (odds ratio=4.45; 95% confidence interval, 1.72 to 11.54; P =0.002), and baseline glomerular filtration rate (odds ratio=0.91; 95% confidence interval, 0.88 to 0.95; P <0.001). Conclusions— In patients with chronic kidney disease, CyC seems to be a reliable marker for the early diagnosis and prognosis of contrast-induced acute kidney injury.

Background—: The RenalGuard System, which creates high urine output and fluid balancing, may be beneficial in preventing contrast-induced acute kidney injury. Methods and Results—: The Renal Insufficiency After Contrast Media Administration Trial II (REMEDIAL II) trial is a randomized, multicenter, investigator-driven trial addressing the prevention of contrast-induced acute kidney injury in high-risk patients. Patients with an estimated glomerular filtration rate ≤30 mL · min ⁻¹ · 1.73 m ⁻² and/or a risk score ≥11 were randomly assigned to sodium bicarbonate solution and N-acetylcysteine (control group) or hydration with saline and N-acetylcysteine controlled by the RenalGuard System and furosemide (RenalGuard group). The primary end point was an increase of ≥0.3 mg/dL in the serum creatinine concentration at 48 hours after the procedure. The secondary end points included serum cystatin C kinetics and rate of in-hospital dialysis. Contrast-induced acute kidney injury occurred in 16 of 146 patients in the RenalGuard group (11%) and in 30 of 146 patients in the control group (20.5%; odds ratio, 0.47; 95% confidence interval, 0.24 to 0.92). There were 142 patients (48.5%) with an estimated glomerular filtration rate ≤30 mL · min ⁻¹ · 1.73 and 149 patients (51.5%) with only a risk score ≥11. Subgroup analysis according to inclusion criteria showed a similarly lower risk of adverse events (estimated glomerular filtration rate ≤30 mL · min ⁻¹ · 1.73 m ⁻² : odds ratio, 0.44; risk score ≥11: odds ratio, 0.45; P for interaction=0.97). Changes in cystatin C at 24 hours (0.02±0.32 versus −0.08±0.26; P =0.002) and 48 hours (0.12±0.42 versus 0.03±0.31; P =0.001) and the rate of in-hospital dialysis (4.1% versus 0.7%; P =0.056) were higher in the control group. Conclusion—: RenalGuard therapy is superior to sodium bicarbonate and N-acetylcysteine in preventing contrast-induced acute kidney injury in high-risk patients. Clinical Trial Registration—: URL: http://www.clinicaltrial.gov . Unique identifier: NCT01098032.

Aims : The aim of this study was to determine the effect of ticagrelor monotherapy on clinically relevant bleeding and major ischaemic events in relation to clinical presentation with and without non-ST elevation acute coronary syndromes (NSTE-ACS) among patients undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DES). Methods and results : We conducted a pre-specified subgroup analysis of The Ticagrelor With Aspirin or Alone in High Risk Patients After Coronary Intervention (TWILIGHT) trial, which enrolled 9006 patients with high-risk features undergoing PCI with DES. After 3 months of dual antiplatelet therapy (DAPT) with ticagrelor plus aspirin, 7119 adherent and event-free patients were randomized in a double-blind manner to ticagrelor plus placebo versus ticagrelor plus aspirin for 12 months. The primary outcome was Bleeding Academic Research Consortium (BARC) type 2, 3, or 5 bleeding while the composite of all-cause death, myocardial infarction (MI), or stroke was the key secondary outcome. Among patients with NSTE-ACS (n = 4614), ticagrelor monotherapy reduced BARC 2, 3, or 5 bleeding by 53% [3.6% vs. 7.6%; hazard ratio (HR) 0.47; 95% confidence interval (CI) 0.36–0.61; P < 0.001) and in stable patients (n = 2503) by 24% (4.8% vs. 6.2%; HR 0.76; 95% CI 0.54–1.06; P = 0.11; nominal P int = 0.03). Rates of all-cause death, MI, or stroke among those with (4.3% vs. 4.4%; HR 0.97; 95% CI 0.74–1.28; P = 0.84) and without (3.1% vs. 3.2%; HR 0.96; 95% CI 0.61–1.49; P = 0.85) NSTE-ACS were similar between treatment arms irrespective of clinical presentation (P int = 0.96). Conclusion : Among patients with or without NSTE-ACS who have completed an initial 3-month course of DAPT following PCI with DES, ticagrelor monotherapy reduced clinically meaningful bleeding events without increasing ischaemic risk as compared with ticagrelor plus aspirin. The benefits of ticagrelor monotherapy with respect to bleeding events were more pronounced in patients with NSTE-ACS. Trial registration: Clinicaltrials.gov identifier: NCT02270242.

Contrast-induced nephropathy accounts for >10% of all causes of hospital-acquired renal failure, causes a prolonged in-hospital stay and represents a powerful predictor of poor early and late outcome. Mechanisms of contrast-induced nephropathy are not completely understood. In vitro data suggests that contrast media (CM) induces a direct toxic effect on renal tubular cells through the activation of the intrinsic apoptotic pathway. It is unclear whether this effect has a role in the clinical setting. In this work, we evaluated the effects of CM both in vivo and in vitro. By analyzing urine samples obtained from patients who experienced contrast-induced acute kidney injury (CI-AKI), we verified, by western blot and immunohistochemistry, that CM induces tubular renal cells apoptosis. Furthermore, in cultured cells, CM caused a dose–response increase in reactive oxygen species (ROS) production, which triggered Jun N-terminal kinases (JNK1/2) and p38 stress kinases marked activation and thus apoptosis. Inhibition of JNK1/2 and p38 by different approaches (i.e. pharmacological antagonists and transfection of kinase-death mutants of the upstream p38 and JNK kinases) prevented CM-induced apoptosis. Interestingly, N-acetylcysteine inhibited ROS production, and thus stress kinases and apoptosis activation. Therefore, we conclude that CM-induced tubular renal cells apoptosis represents a key mechanism of CI-AKI.