The REMEDIAL III study showed that a urine-flow-rate-guided approach carried out by the RenalGuard system is superior to left ventricular end-diastolic pressure-guided hydration to prevent contrast-induced acute kidney injury (CI-AKI) in patients at high risk of suffering CI-AKI, according to the results presented Sunday at Transcatheter Cardiovascular Therapeutics 2019 in San Francisco.
Carlo Briguori, MD, PhD, of Mediterranea Cardiocentro, Naples, Italy, presented the study.
REMEDIAL III is a multicenter, randomized, single-blind, phase 3, investigator-initiated trial comparing left ventricular end diastolic pressure (LVEDP)-guided hydration to urine flow rate (UFR)-guided hydration. In all cases, iobitridol (Xenetix, Guerbet, Villepinte, France) a low-osmolar, non-ionic contrast agent, was administered.
In the UFR-guided group, fluids and intravenous furosemide were given to reach a flow rate >300 ml/hr preprocedurally, and flow was maintained at ≥ 450 ml/hr during and after the procedure. In the LVEDP group, hydration was adjusted on the basis of the LVEDP measurement. Preprocedure LVEDP measurement was obtained by echocardiographic E/E’ ratio. All patients with chronic kidney disease (CKD) and estimated glomerular filtration rate ≤45 ml/min/1.73 m2 and/or at risk for CI-AKI according to Mehran’s score ≥11 and/or Gurm’s score >7 were included. Patients with acute myocardial infarction (ST-elevation myocardial infarction), acute pulmonary edema, cardiogenic shock, end-stage dialysis dependent CKD, multiple myeloma, and recent contrast exposure were excluded.
A total of 933 patients were assessed, and 708 were randomized. Of randomized patients, 353 were allocated to the UFR group and 355 to the LVEDP group. Mean age was 74±8 years and mean Mehran risk score was 10±3 in both the groups. No significant differences were noted in baseline characteristics between the groups.
Hydration and urine output were significantly higher in the UFR-guided group. The primary endpoint of CI-AKI was significantly lower in UFR-guided group when than in the LVEDP-guided group (UFR 5.7% vs. LVEDP 10.3%; risk ratio, 0.56; 95% confidence interval, 0.39 to 0.79; p=0.036). The rate of pulmonary edema was also lower in the UFR group.
In prespecified subgroups based on LVEDP and UFR, UFR-guided therapy continued to show benefit in decreasing CI-AKI. Cumulative major adverse events, which is a composite of death, dialysis, sustained kidney damage and acute pulmonary edema, was significantly lower in the UFR-guidd group (UFR 7.1% vs. LVEDP 12%; p=0.03). However, hypokalemia was significantly higher in the UFR-guided group (UFR 6.2% vs. LVEDP 2.3%; p=0.01).
Biguori concluded that the UFR-guided approach carried out by RenalGuard system (RenalGuard Solutions) is superior to the LVEDP-guided hydration regimen to prevent CI-AKI and recommended close monitoring of potassium levels when this approach is used.
Guerbet provided an unrestricted grant to the Mediterranea Cardiocentro for the conduct of this study.