A minimally invasive repair for a failing heart valve may also help protect the kidneys, according to a new study of patients with severe tricuspid regurgitation. Researchers at Robert Bosch Hospital in Stuttgart, Germany, found that kidney function improved after transcatheter tricuspid edge-to-edge repair, or T-TEER, while episodes of acute kidney injury fell sharply across nearly every stage of chronic kidney disease. The findings suggest that treating a leaky tricuspid valve could influence more than breathlessness and fluid retention: it may also interrupt a damaging cycle linking the heart, circulation and kidneys. The study, published in Clinical Research in Cardiology, found a median increase in estimated glomerular filtration rate of 4.8 millilitres per minute per 1.73 square metres after the procedure. Although the researchers describe an association rather than proof that the intervention directly caused the improvement, the results raise the possibility that valve repair could preserve renal function in a population traditionally considered medically fragile.
Tricuspid regurgitation occurs when the tricuspid valve, which separates the right atrium from the right ventricle, fails to close tightly. With each heartbeat, some blood flows backward instead of moving efficiently toward the lungs. Over time, this reverse flow can enlarge the right-sided chambers of the heart and raise pressure in the veins that return blood from the body. Patients may develop swelling in the legs and abdomen, liver congestion, fatigue and severe shortness of breath. The kidneys can suffer as well. In heart failure, reduced forward blood flow may limit renal perfusion, while elevated venous pressure can transmit backward into the veins surrounding the kidneys. This combination can reduce the pressure gradient that drives filtration. Fluid accumulation may then prompt clinicians to use diuretics, which relieve congestion but can further challenge kidney function if circulating volume falls too quickly. The resulting interaction is often described as cardiorenal syndrome, in which deterioration of one organ accelerates dysfunction in the other.
T-TEER is designed to reduce the backward leak without open-heart surgery. During the procedure, physicians guide a catheter through a vein into the heart and position a small clipping device across the tricuspid valve leaflets. The device grasps and brings portions of the leaflets together, creating a more effective seal and reducing the regurgitant opening. Unlike valve replacement, the technique leaves the native valve in place and is performed through a catheter rather than through a large chest incision. It is therefore particularly attractive for older patients or people whose surgical risk is elevated because of heart failure, kidney disease or other illnesses. By reducing the volume of blood pushed backward with each contraction, the repair can lower right-sided filling pressures and lessen systemic venous congestion. The Stuttgart researchers set out to determine whether that altered circulation was reflected in measurable changes in kidney function and in the frequency of acute kidney injury.
The retrospective study included 181 consecutive patients who underwent T-TEER at Robert Bosch Hospital between March 2021 and February 2023. The investigators analysed routine electronic health-record data collected before and after the intervention, excluding patients whose records did not contain sufficient information. Follow-up lasted a median of 125 days, although the range extended from six days to 506 days for the central interval reported, with some patients followed for as long as 1,280 days. The cohort was examined according to the severity of pre-existing chronic kidney disease, using estimated glomerular filtration rate, or eGFR, as a central measure. eGFR is calculated from blood markers and demographic variables to approximate how much plasma the kidneys filter each minute, with the result normalized to a standard body-surface area of 1.73 square metres. Lower values generally indicate more advanced renal impairment. The analysis also tracked markers associated with congestion and metabolic balance, including gamma-glutamyl transferase, or GGT, and blood potassium, as well as acute kidney injury after the procedure.
Across the study population, eGFR rose by a median of 4.8 millilitres per minute per 1.73 square metres, with the improvement reaching statistical significance at p less than 0.001. The reported interquartile range was 3.1 to 6.5 millilitres per minute per 1.73 square metres, indicating the central spread of individual changes. The increase was accompanied by reductions in GGT and potassium. GGT is an enzyme often used to assess hepatobiliary stress and can rise when the liver is affected by systemic venous congestion; a decline may therefore be consistent with relief of pressure in the right-sided circulation, although it is not a direct measurement of kidney filtration. Potassium is tightly regulated by the kidneys and can accumulate when renal excretion is impaired. Its reduction after repair may reflect improved renal handling, changes in medications or altered clinical status. Patients with chronic kidney disease showed improvement across nearly all disease stages, whereas those who began with preserved renal function, defined in the report as eGFR of at least 60, largely remained stable rather than improving.
The most striking signal involved acute kidney injury. According to the study, the incidence of AKI decreased in every chronic kidney disease group after T-TEER. Rate ratios ranged from 0.18 to 0.39, corresponding to an estimated 60 to 80 per cent reduction compared with the relevant pre-procedure or baseline period. Following the intervention, AKI rates no longer differed between the various CKD stages. That finding is important because patients with poorer kidney function are usually more vulnerable to abrupt declines in filtration during hospitalization or after invasive cardiovascular procedures. AKI can result from several mechanisms, including reduced perfusion, venous congestion, contrast exposure, inflammation and medication effects. The study does not establish which of these mechanisms changed after valve repair. However, the disappearance of the difference between CKD categories suggests that reducing the hemodynamic burden of severe tricuspid regurgitation may have helped narrow a risk gap that normally favours patients with healthier kidneys.
The biological explanation proposed by the results centres on congestion rather than on a direct effect of the clipping device on renal tissue. When right atrial and central venous pressures remain high, pressure can be transmitted through the large veins into the renal veins and the low-pressure compartments around the kidneys. This may compress small vessels and tubules, a concept sometimes described as renal tamponade or renal compression. At the same time, heart failure can reduce effective arterial blood flow reaching the kidneys. Filtration depends on the balance between pressures entering and leaving the glomerular capillaries, the microscopic structures where blood is filtered. Excessive venous pressure can reduce that gradient even when arterial pressure appears acceptable. Repairing the tricuspid valve could therefore improve filtration by lowering downstream pressure and allowing more effective forward circulation. The reductions in GGT and potassium provide additional, though indirect, evidence that the procedure was accompanied by less systemic congestion and improved physiological stability.
The investigators caution that their work is not a randomized clinical trial and cannot demonstrate that T-TEER itself caused the renal recovery. The study was conducted at a single hospital, involved 181 patients and relied on routine electronic records, which can contain missing measurements and variation in the timing of laboratory tests. Follow-up duration also varied substantially between individuals. Changes in diuretic treatment, blood pressure, fluid management, contrast use, infection, nutrition or other aspects of care could have influenced eGFR and AKI risk. In addition, eGFR can fluctuate with hydration and acute illness, and a modest numerical increase does not necessarily mean that structural kidney damage has reversed. The findings nevertheless align with the clinical logic that relieving severe right-sided congestion may benefit the kidneys, particularly in patients whose renal function is already compromised. Prospective studies with standardized measurements, longer follow-up and comparison groups will be needed to determine whether the renal changes translate into fewer hospitalizations, slower progression of CKD or improved survival. For now, the study adds kidney preservation to the growing list of potential consequences of successful transcatheter treatment for severe tricuspid regurgitation.
Subject of Research: Renal function and acute kidney injury after transcatheter tricuspid edge-to-edge repair in patients with severe tricuspid regurgitation and chronic kidney disease
Subject of Research: Medicine
Article Title: Response in renal function after transcatheter tricuspid edge-to-edge repair
Article References: Becker, M., Kraft, L., Oberacker, T., Schricker, S., Mueller-Kuehnle, J., Riegger, L., Grau, J., Biegger, D., Eker Dayi, B., Nikolai, P., Klenk, J., Rapp, K., Bekeredjian, R., Latus, J., & Schanz, M. (2026). Response in renal function after transcatheter tricuspid edge-to-edge repair. Clinical Research in Cardiology. https://doi.org/10.1007/s00392-026-02961-z
Image Credits: AI Generated
DOI: 10.1007/s00392-026-02961-z
Keywords: tricuspid regurgitation, T-TEER, transcatheter valve repair, cardiorenal syndrome, chronic kidney disease, renal function, acute kidney injury, venous congestion
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Arden W. (August 29, 2026). Kidney Function Improves After Transcatheter Tricuspid Edge-to-Edge Repair. Scienmag. https://scienmag.com/kidney-function-improves-after-transcatheter-tricuspid-edge-to-edge-repair/
Arden W. “Kidney Function Improves After Transcatheter Tricuspid Edge-to-Edge Repair.” Scienmag, 29 August 2026, https://scienmag.com/kidney-function-improves-after-transcatheter-tricuspid-edge-to-edge-repair/. Accessed 29 August 2026.
Arden W. “Kidney Function Improves After Transcatheter Tricuspid Edge-to-Edge Repair.” Scienmag. August 29, 2026. https://scienmag.com/kidney-function-improves-after-transcatheter-tricuspid-edge-to-edge-repair/
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Tags: acute kidney injury reductionchronic kidney disease managementcirculatory and renal health connectionheart failure and kidney healthheart failure and kidney protectionheart-kidney interactionimpact of tricuspid repair on renal healthimpact of valve repair on kidney healthinnovative cardiology procedureskidney function improvementminimally invasive heart valve repairrenal function preservationT-TEER procedure outcomestranscatheter tricuspid edge-to-edge repairtranscatheter valve interventionstricuspid regurgitation treatment
