Detection and treatment of transplant renal artery stenosis

Outcomes of endovascular treatment of renal arterial stenosis in transplanted kidneys

Objective

To evaluate the effectiveness and outcomes of endovascular treatment of TRAS with PTA.

Materials and Methods

We searched our prospectively collected database looking at cases of TRAS between January 2005-December 2011. CCT was the gold-standart for diagnosis of TRAS. Parameters analysed comprised technical aspects, arterial blood pressure variation, and renal function. A minimum follow-up of 24 months was considered.

Results

Of the 2221 renal transplants performed in the selected period, 22 (0.9%) patients were identified with TRAS. Fourteen (63.6%) were male and mean age was 377±14.8years (12-69). Kidney graft was from deceased donnors in 20 (80%) cases. On doppler evaluation, mean blood flow speed after transplantation, at TRAS diagnosis and after TAP was 210.6±99.5, 417±122.7 and 182.5±81.6mL/sec, respectively (p<0.001). For SBP and DBP, there was a significant difference between between pre-intervention and all post-treatment time points (p<0.001). After 1 month of the procedure, there was stabilization of the Cr level with a significant difference between mean Cr levels along time (p<0.001). After a mean follow-up of 16±4.2 (3-24) months, overall success rate was 100%.

Conclusions

Endovascular treatment with PTA/stenting is a safe and effective option for managing TRAS, ensuring the functionality of the graft and normalization of blood pressure and renal function.

Three-Dimensional Computed Tomography Reconstruction in Transplant Renal Artery Stenosis

OBJECTIVES

Transplant renal artery stenosis is a frequently recognized complication of kidney transplant procedures. A single-center retrospective study was conducted to examine the use of 3-dimensional computed tomography reconstruction in diagnosing transplant artery stenosis.

MATERIALS AND METHODS

During 2013 at our center, 86 patients underwent kidney transplant. All patients underwent ultrasonographic analyses. Patients with clinically suspected transplant renal artery stenosis were examined by 3-dimensional computed tomography reconstruction and were treated with endovascular approaches or medically managed.

RESULTS

Ten patients were diagnosed with transplant renal artery stenosis by 3-dimensional computed tomography reconstruction. No evidence of contrast-induced nephrotoxicity was observed. Nine of the 10 patients underwent percutaneous transluminal angio-plasty, whereas the remaining patient was treated conservatively. Procedural success rate was 100%. Patients were followed for a mean period of 20 ± 3 months. Blood pressure improved from a mean of 163/90 to 132/73 mm Hg at the end of the follow-up period. In the 9 patients who underwent angioplasty, serum creatinine improved from 198 ± 24 to 134 ± 16 μmol/L at the end of the follow-up period. The cystatin C level in some patients declined after interventional therapy.

CONCLUSIONS

Three-dimensional computed tomography reconstruction is a safe choice for patients who present with increased serum creatinine levels and refractory hypertension. Percutaneous transluminal angioplasty is the preferred therapeutic technique for transplant renal artery stenosis.

Evaluation of the Vascular Surgical Complications of Renal Transplantation

BACKGROUND

Renal transplantation is the treatment of choice of end-stage renal failure. However, vascular surgical complications can compromise the functional prognosis of the transplant or even be life threatening in the short term. Since few data are available in the literature, the objective of this study was to evaluate the vascular surgical complications of renal transplantation.

METHODS

In a retrospective and monocentric study, the records of all the patients receiving a kidney transplant between January 2008 and December 2014 were reviewed. The demographic data and the follow-up of the patients who presented a vascular surgical complication in relation to their transplant were collected. Minor, intermediate, or major vascular complications were defined according to the need for monitoring, reoperation, or the risk of transplant loss or a life-threatening situation. Predictive factors of vascular complications were also looked for.

RESULTS

Mean age was 50.9 ± 15.0 years, and 312 kidney transplants were carried out (205 men). Fifty vascular surgical complications (16.0%) were found. Among them, 23 vascular complications (7.4%) were major, including 6 (1.9%) which required transplantectomy, after 4 arterial thromboses (1.3%), 1 early venous thrombosis (0.3%), and 1 injury of the inferior vena cava (0.3%). Twelve complications (3.8%) were minor. Surgical revision was necessary in 76% of the vascular complications (n = 38). The average follow-up of the transplanted population was 37.4 ± 24.0 month, 268 kidney transplants (85.8%) were functional and 21 patients (6.7%) returned to dialysis. Surgical complications were more frequent when the recipient had hypertension (P = 0.02, OR = 2.5; 95% CI [1.1-6.1]), in case of right kidney transplant (P = 0.0004, OR = 3.1; 95% CI [1.6-5.8]) and when the kidney hilum consisted of at least arteries (P = 0.02, OR = 10.0; 95% CI [1.3-34]). Male gender (P = 0.03, OR = 0.5; 95% CI [0.3-0.9]) as well as the choice of the common iliac arterial (P = 0.001, OR = 0.4; 95% IC [0.2-0.7]) and venous (P = 0.002, OR = 0.3; 95% IC [0.2-0.8]) axes to carry out the vascular anastomoses appeared as protective factors.

CONCLUSIONS

The vascular surgical complications of kidney transplantation, especially thromboses, can be serious and lead to transplant loss. The expertise of vascular surgeons finds its place here and makes it possible to maintain low rates of vascular complications and loss of transplants.

Management of transplant renal artery stenosis

End-stage renal disease (ESRD) was universally fatal until dialysis (peritoneal and hemodialysis) and renal transplantation were introduced. However, there are multiple complications associated with transplantation including transplant renal artery stenosis (TRAS). Transplant renal artery stenosis is an important cause of premature renal failure, uncontrolled hypertension, and allograft loss. There are 3 treatment modalities available for TRAS: optimal medical therapy alone, percutaneous intervention, and surgical revascularization both with optimal medical therapy. Percutaneous transluminal angioplasty (PTA) has now become the initial treatment of choice for TRAS. However, there are conflicting data regarding the efficacy of PTA, with growing evidence showing lack of significant benefit in blood pressure (BP) or renal function in patients undergoing PTA versus medical management. However, there have been no randomized control studies that have established the superiority of either method. We review the existing data and analyze management of TRAS as reported in multiple case series including findings from our center.

Management of transplant renal artery stenosis and its impact on long-term allograft survival: a single-centre experience

BACKGROUND

Transplant renal artery stenosis (TRAS) is a recognized complication resulting in post-transplant hypertension associated with allograft dysfunction. It is a commonly missed but potentially treatable complication that may present from months to years after transplant surgery. In this retrospective study, we compared management strategies and outcomes of TRAS from 1990 to 2005.

METHODS

Case notes of transplant recipients with TRAS demonstrated by angiography were reviewed. Angiography and was carried out when there was a clinical or Doppler ultrasound suspicion of TRAS. The clinical diagnosis of TRAS was based on uncontrolled refractory/new-onset hypertension and/or unexplained graft dysfunction in the absence of another diagnosis, such as rejection, obstruction or infection. The two-tailed Student t-test was used to analyse the differences between mean arterial pressure, serum creatinine, and estimated glomerular filtration rate before and after the intervention.

RESULTS

Sixty-seven patients with angiogram-confirmed TRAS were included. Forty-four, 9 and 14 patients were managed with primary percutaneous transluminal renal angioplasty (PTRA), surgical intervention and conservative treatment, respectively. Uncontrolled hypertension was the most common presentation noted in 74.62%. Post-anastamotic single stenosis was the commonest occurrence (n = 53). Angioplasty had the highest 1- and 5-year graft survival rate of 91% and 86%, respectively. The worst prognosis was noted in patients treated with secondary PTRA after failed surgery or secondary surgery after failed primary PTRA.

CONCLUSIONS

TRAS is a recognized complication resulting in loss of renal allografts. Early Doppler ultrasound is a good primary diagnostic tool. Early intervention is associated with a good long-term graft function.