Vascular Complications After Kidney Transplantation
Recruiting · NCT07531966 · Observational (researchers observe without assigning treatment) · Lead sponsor: University of Aarhus
View the official record on ClinicalTrials.gov →Interventions studied
What this trial is about
* To determine the incidence of arterial inflow problems and venous outflow problems as causes of impaired renal function and/or treatment-resistant hypertension after kidney transplantation, when all kidney-transplant recipients in Denmark are evaluated according to uniform, well-defined clinical criteria. * To investigate the efficacy and safety of catheter-based balloon treatment (percutaneous transluminal angioplasty, PTA) for these vascular complications, of which transplant renal artery stenosis is by far the most common. * To assess whether novel imaging and functional diagnostic methods can predict treatment response.
Who can take part
Inclusion criteria
- \. At least one of the following clinical criteria (1 or 2) must be fulfilled:
- Graft dysfunction, defined by at least one of the following:
- Acute reduction in estimated glomerular filtration rate (eGFR) \>15% on two consecutive measurements at least 2 weeks apart, with other causes excluded (rejection, obstruction, infection).
- eGFR \<50% of the expected value 30 days after kidney transplantation of unknown cause.
- Decline in eGFR \>30% after initiation of an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker.
- Persistent resistant hypertension for more than 6 weeks after kidney transplantation, defined as:
- 24-hour ambulatory systolic blood pressure \>130 mmHg despite treatment with at least three classes of antihypertensive medication at maximally tolerated doses (including diuretics, if tolerated).
- Together with at least one of the following radiological criteria:
- CT or MR angiography demonstrating a lumen reduction ≥50%.
- Doppler ultrasound showing:
- Peak systolic velocity in the renal artery ≥200 cm/s and a renal renal ratio (velocity at stenosis / velocity in distal artery) \>4.
- Acceleration time \>70 ms in intrarenal arteries.
- \. In cases of strong clinical suspicion of a vascular complication where CT or MR angiography cannot reliably exclude graft artery or vein stenosis, patients may be referred for confirmatory invasive investigations.
- Before PTA, catheter-based angiography and translesional pressure measurements are performed to confirm whether the patient meets the radiological eligibility criterion for PTA:
- Stenosis ≥70%.
- Stenosis 50-69% if at least one of the following criteria is met:
- Mean translesional pressure gradient ≥10 mmHg.
- Systolic pressure gradient ≥20 mmHg.
- Renal Pd/Pa ≤0.8.
- If pressure measurements cannot be obtained, treatment is based on the operator's clinical judgement.
Exclusion criteria
- Inability to provide informed consent.
- Concurrent biopsy demonstrating rejection requiring treatment.
- Pregnancy.
- Previous PTA of the same vessel.
- Patients unable to tolerate any form of antithrombotic therapy and therefore not eligible for stent placement.
Where it is running
6 locations listed.
- Aarhus University Hospital - Aarhus, Denmark
- Aarhus University Hospital - Aarhus, Denmark
- Rigshospitalet - Copenhagen, Denmark
- Rigshospitalet - Copenhagen, Denmark
- Odense University Hospital - Odense, Denmark
- Odense University Hospital - Odense, Denmark