RenalGuard, a medical device that delivers real-time isotonic intravenous (IV) hydration matched with furosemide-induced diuresis, does not decrease the risk for contrast-induced nephropathy (CIN) compared with adequate conventional IV hydration in high-risk patients undergoing complex cardiovascular interventions, according to a recent study.
In the STRENGTH (Study Evaluating the Use of RenalGuard to Protect Patients at High Risk of AKI) study, investigators assessed whether RenalGuard is superior to conventional IV hydration in preventing CIN in patients with moderate to severe chronic kidney disease (estimated glomerular filtration rate [eGFR] 15-40 mL/min/1.73 m2) undergoing complex percutaneous coronary, peripheral, and structural interventions with expected contrast media doses of at least 3 times the eGFR. The study included 259 patients with a mean age of 79 years. The primary endpoint was the incidence of CIN at day 3 after the procedure.
The investigators defined CIN as a 0.3 mg/dL or greater increase in serum creatinine and/or a 25% or greater increase in serum creatinine from baseline at around day 3 or the need for dialysis within 5 days of the procedure.
The primary endpoint occurred in 17 (15.9%) of the 107 patients in the RenalGuard group and 15 (13.9%) of the 110 patients in the control group, a nonsignificant difference, Sarah Mauler-Wittwer, MD, of Hôpital Privé Jacque Cartier, Institut Cardiovasculaire Paris-Sud, Ramsay-Santé in Massy, France, and colleagues reported in JACC: Cardiovascular Interventions.1
The investigators found no significant difference between the study arms in the individual components of the CIN definition and in secondary outcomes, which included major adverse cardiovascular and cerebrovascular events, change in serum creatinine and eGFR values at 12 months, and percentage of patients on chronic or temporary hemodialysis as 12 months.
The mean contrast volume administered was similar in the RenalGuard and control group (116 mL and 104 mL, respectively).
The authors acknowledged that their findings differ from those of previous randomized controlled trials, which found that RenalGuard significantly reduced the rate of CIN in patients undergoing cardiovascular procedures. They noted, for example, that the REMEDIAL II trial of patients with CKD undergoing cardiovascular procedures demonstrated a CIN rate of 11% with RenalGuard compared with 20.5% in the control group.2 The PROTECT-TAVI trial revealed a CIN rate of 5.4% with RenalGuard vs 25.2% in the control group among patients undergoing transcatheter aortic valve replacement.3 Putting their findings into perspective, Dr Mauler-Wittwer and colleagues noted that their study population had a higher risk profile compared with previous trials, which could have resulted in a higher rate of kidney injury in both study arms. Nearly 60% of patients had dyspnea in New York Heart Association functional class III or IV, and their study population had more severe renal insufficiency compared with patients in other trials, they pointed out.
- Mauler-Wittwer S, Sievert H, Ioppolo AM, et al. Study evaluating the use of RenalGuard to protect patients at high risk of AKI. J Am Coll Cardiol Intv. 2022;15:1639-1648. doi:10.1016/j.jcin.2022.05.036
2. Briguori C, Visconti G, Focaccio A, et al.Renal insufficiency after contrast media administration trial II (REMEDIAL II): RenalGuard system in high-risk patients for contrast-induced acute kidney injury. Circulation. 2011;124:1260-1269. doi:10.1161/circulationaha.111.030759
3. Barbanti M, Gulino S, Capranzano P, et al. Acute kidney injury with the RenalGuard system in patients undergoing transcatheter aortic valve replacement: The PROTECT-TAVI trial (PROphylactic effecT of furosEmide-induCed diuresis with matched isotonic intravenous hydraTion in Transcatheter Aortic Valve Implantation). J Am Coll Cardiol Intv. 2015;8:1595-1604. doi:10.1016/j.jcin.2015.07.012