Groundbreaking Renal Assist Device Intervening to ENhance cardioThoracic Surgery Outcomes

Overview

Patients with renal insufficiency who undergo cardiac surgery with cardiopulmonary bypass (CPB) are at significant risk for exacerbation of renal dysfunction postoperatively. This in turn is associated with an increased risk of prolonged intensive care unit (ICU) length of stay, other comorbidities including surgical complications and 30-day mortality. Renal impairment is generally identified based on an increase in serum creatinine concentration and/or a certain magnitude decrease in estimated glomerular filtration rate (eGFR). The JuxtaFlow® Renal Assist Device (RAD) is designed to sustain or enhance glomerular filtration perioperatively for patients with renal insufficiency by applying a mild controlled negative pressure to the collecting system via the renal pelvis, thereby increasing effective filtration pressure and reducing tubular pressure. This mechanism is designed to support the kidneys' functions during times of renal stress that would be associated with intrarenal edema, volume overload, increased venous pressure, and inflammatory response. By supporting renal function, specifically during the acute stress of CPB, JuxtaFlow holds promise to protect nephron function, decrease renal hypoxia, and provide multifactorial kidney function support to maintain their ability to manage future stress.

Interventions

• Device Renal assist device
  The JuxtaFlow RAD includes two endoscopically placed ureteral catheters connected to a bedside pump system. The catheters are designed to deliver a mild, controlled negative pressure (-15 mmHg ± 2mmHg) into the renal pelvis of each kidney for up to 72 hours. This pressure is designed to diffuse through each of the million nephrons lowering intratubular pressure thereby improving the filtration gradient at the glomerulus while supporting overall kidney function.

Primary outcome measures

• Mean Peak Percent Change in Serum Creatinine [Time frame: 96 hours peri-operative]
• Incidence of Treatment-Emergent Adverse Events [Time frame: From enrollment to post-operative day 30]

Secondary outcome measures (4)

• AUC Serum Creatinine [Time frame: 96 hours peri-operative]
• Creatinine Clearance [Time frame: 24 to 48 hours post-operatively]
• AKI incidence [Time frame: From post-operative day 1 to 14]
• Critical Care Length of Stay [Time frame: through study study completion, an average of 1 year]

Eligibility criteria

Inclusion criteria

To be eligible for participation in this study, an individual must meet all the following criteria:

• A candidate for elective or urgent on-pump coronary artery bypass grafting (CABG) and/or valvular surgery
• Male or Female age 22 to 85 years
• Estimated glomerular filtration rate (eGFR) 15 - 60 mL/min/1.73m2
• Signed and dated informed consent
• Female patients of childbearing potential must:

• have negative pregnancy test at the informed consent visit,
• be using previously initiated approved and effective contraception from the informed consent visit through completion of the study \*The only recommended contraception is condoms.

Exclusion criteria

An individual who meets any of the following criteria will be excluded from participation in this study:

• Any individual, or their legally authorized representative (LAR), who does not understand the requests and risks of participating in the clinical trial or is unable to give informed consent
• Pregnancy or lactation
• Prior cardiac surgery within the last 6 months
• Hemodynamic instability as determined by the Principal Investigator
• Immunosuppression
• Active infections (e.g. HIV, Tbc, and all types of Hepatitis)
• History of polycystic kidney disease
• Patients with only one active kidney or one poorly functioning kidney
• Evidence of current kidney obstruction (e.g., Kidney stones)
• Evidence of current hydronephrosis
• Active upper and/or lower urinary tract infections
• Malignancy; oncological Surgery within 5 years or ongoing antitumoral treatment
• Ongoing sepsis or endocarditis
• Patients who have an expected 30-day postoperative mortality greater than 10% as determined by the Principal Investigator
• Any secondary condition as determined by the investigator that would place the subject at an increased risk or preclude the subject's full compliance with the study procedures, including injuries to the urinary organs and/or external genitals; or severe BPH
• Unexplained/unexpected gross hematuria as determined by the Investigator
• Current or planned treatment with an investigational drug (IND), device (IDE), or other investigational intervention within 3 months prior to or during participation in this clinical trial
• Patients who have a current unrepaired ureteral avulsion as determined by the investigator
• Patients otherwise contraindicated for urological interventions, including ureter guidewire placement via bladder cystoscopy and ureteral catheterization, or otherwise contraindicated for any of the other study procedures

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Prevention

Study locations

United States · 4 centers

• Cleveland Clinic Florida — Weston
• University of Michigan — Ann Arbor
• University of North Carolina — Chapel Hill
• University of Cincinnati — Cincinnati

Poland · 3 centers

• American Heart of Poland — Bielsko-Biala
• Poznan University of Medical Sciences — Poznan
• Medicover Hospital — Warsaw

Publications

• Rodriguez E, Petrovic M, Milewski K, et al. Feasibility Study of Renal Negative Pressure Treatment after Cardiac Surgery with Cardiopulmonary Bypass. Ann Thorac Surg Short Rep. 2026 Feb 25. doi: [DOI]. Epub ahead of print.
• Rao VS, Maulion C, Asher JL, Ivey-Miranda JB, Cox ZL, Moreno-Villagomez J, Mahoney D, Turner JM, Wilson FP, Wilcox CS, Testani JM. Renal negative pressure treatment as a novel therapy for heart failure-induced renal dysfunction. Am J Physiol Regul Integr Comp Physiol. 2021 Oct 1;321(4):R588-R594. doi: 10.1152/ajpregu.00115.2021. Epub 2021 Aug 18. PMID 34405731

Identifiers

NCT: NCT07017933 · GRADIENT 20-10

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗