Percutaneous transluminal angioplasty treatment of renal transplant artery stenosis

Endovascular Treatment for Transplant Renal Artery Stenosis: 10 Years' Experience from a Single Center

INTRODUCTION

Transplant renal artery stenosis (TRAS) is a common post-renal transplant complication. Although endovascular treatment is widely used to treat TRAS, previous research has been limited by small sample sizes. This article aimed to present the clinical outcomes of endovascular treatment for TRAS in a large sample.

METHODS

Between January 2010 and December 2019, this study included patients with TRAS who were admitted to our center. All patients' clinical symptoms, comorbidities, imaging data, treatment, and follow-up results were reviewed retrospectively.

RESULTS

Seventy two patients participated in this study. The median time between renal transplantation and TRAS was 5.25 months. Out of 72 patients, 55 (76.4%) received balloon dilatation in conjunction with stent deployment, 10 (13.9%) received drug-coated balloon dilatation alone, and 7 (9.7%) received balloon dilatation alone. The median follow-up period was 27 months. Primary patency rates were 100%, 81.8%, 74.5%, 64.6%, and 61.8% at 1, 3, 6, 12, and 24 months. A total of 23 patients were found to have restenosis during follow-up, with 6 (26.1%) requiring reintervention and none remaining restenosis after the second treatment. In the subgroup analysis of the three types of stenosis, patients with transplant renal stenosis at the anastomosis had a significantly higher rate of primary patency. Between endovascular treatments, the primary patency rate, postoperative creatinine clearance, and mean systolic blood pressure did not differ significantly.

CONCLUSION

Endovascular treatment resulted in favorable short-term patency as well as effective relief of renal dysfunction and renal hypertension in TRAS patients.

Transplant renal artery stenosis caused by the stretch of an artey branch: a case report and literature review

Background

Renal transplant is the preferred treatment option for these patients with end-stage renal disease. Transplant renal artery stenosis (TRAS) is one of the most common and serious vascular complications after renal transplantation, and most of the TRAS occurred in the anastomosis. The complication must be diagnosed and treated timely, otherwise the function of transplanted kidney may be losed.

Case presentation

A 46-year-old male with end-stage renal disease of unknown cause received a cadaveric renal transplant one year ago. Although three antihypertensive medications were administrated, his blood pressure gradually increased to 190/120 mmHg 3 weeks posttransplantation. Also the level of creatinine increased to 194 μmol/L.Color Doppler ultrasonography indicated a decreased resistance index (RI) in intrarenal arteries and increased blood flow of the transplant renal artery, therefore, a vascular complication of TRAS was suspected. Arteriography was performed and demonstrated TRAS caused by stretch of an artery branch, and the TRAS occurred in the distal site of the anastomosis instead of the anastomosis. Percutaneous transluminal bare stent implantation treatment was successfully performed. Satisfactory clinical efficacy with improvement in transplant renal function and renovascular hypertension was achieved after the interventional treatment.

Conclusion

To our knowledge this is the first reported case of TRAS caused by stretch of an artery branch. When refractory hypertension and allograft dysfunction are presented posttransplantation, TRAS should be suspected. Color Doppler ultrasonography as a non-invasive examination may provide some valuable information, three-dimention CT can be useful for further diagnosis, but is seldom necessary. Arteriography provides the definitive diagnosis of TRAS. Percutaneous transluminal stent implantation treatment of TRAS has high success rate with minimal invasion and complications. When an artery branch situated on the stenosis, a bare stent rather than covered stent is the preferred choice.

Complications of transplantation. Part 1: renal transplants

Vascular complications after solid-organ transplantation are not uncommon and may lead to graft dysfunction and ultimately graft loss. A thorough understanding of the surgical anatomy, etiologies, and types of vascular complications, their presentation, and the options for management are important for managing these complex patients. This article reviews the basic surgical anatomy, vascular complications, and endovascular management options of vascular complications in patients with renal transplants.

Management of transplant renal artery stenosis

Transplant renal artery stenosis is the most frequent vascular complication of transplantation. Early detection and correction reduce patients' morbidity and allograft dysfunction. Although noninvasive imaging can detect an underlying stenosis, angiography with subsequent angioplasty or stenting, or both, provides definitive diagnosis and treatment. With the introduction of alternative contrast agents and newer catheter and stent technology, these procedures can be performed safely with little risk of contrast-induced nephropathy or allograft loss.

Hypertension following kidney transplantation

The majority of patients become hypertensive following kidney transplantation. Its occurrence is associated not only with increased fatal and nonfatal cardiovascular events but also with decreased allograft survival. This review summarizes the current knowledge of the epidemiology, etiology, pathophysiology, and management of post-transplant hypertension.

Restoration of failed renal graft function after successful angioplasty of pressure-resistant renal artery stenosis using a cutting balloon: a case report

This study is the report of a 37-year-old male with a transplanted kidney from a 3.5-year-old donor: the graft had two arteries transplanted with an aortic patch to an external iliac artery. Four months after transplantation, the graft function deteriorated, together with the development of hypertension. Stenosis of both graft arteries was detected and the patient was referred for angioplasty. The angiographic result was suboptimal, nevertheless, the graft function improved and was more or less stable (serum creatinine, 160-200 micromol/l) for 4 years, along with persistently difficult-to-control hypertension. Five years after transplantation, the graft function deteriorated again and severe graft artery restenosis was detected. The restenosis did not respond to dilatation, graft function failed, hypertension decompensated, and left ventricular failure developed. The patient required dialysis. A cutting balloon angioplasty opened the artery, and kidney function was restored after a few days: the serum creatinine level dropped to 140-160 micromol/l, and the glomerular filtration rate (creatinine clearance) to 0.65 ml/min/1.73 m(2). The graft function has now been stable for more than 2 years, however, the hypertension is still difficult to control.

Long-term follow-up of renal transplant patients with renal artery stenosis treated by percutaneous angioplasty

PURPOSE OF THE STUDY

To evaluate if renal angioplasty (PTRA) in patients with transplanted kidney and renal artery stenosis (TRAS) can have long-term effect on hypertension and renal function.

MATERIALS AND METHODS

Within a 24-year time period, 58 PTRAs in 55 adults (three times Re-PTRA) with transplanted kidney were performed. The group included 34 males and 21 females, average age 41+/-10.6 (18-72) years. After exclusion of 7 technical failures, 51 PTRAs were followed at 1 week, 6 months and 1-3 years after PTRA. Hypertension improvement was defined as mean arterial pressure (MAP) decrease of at least 15% from the pre-PTRA value. Graft function was evaluated by serum creatinine (Scr) and creatinine clearance (Ccr) levels, and the improvement was defined as a 20% change. Clinical FU was 3 years.

RESULTS

PTRA technical success was 88.4%. In 51 kidney recipients at the end of FU, blood pressure improved in 65.2% of patients (MAP decreased from 123+/-13.1 to 107+/-12.1 mmHg), but no patient remained normotensive medication free. Graft function improved in 44.8% of patients and was stabilized in 20.7% of them (average Ccr before PTRA: 0.48+/-0.29, after PTRA: 0.78+/-47 ml/s). PTRA complications were observed in 25.5% of procedures, most often with no clinical sequel. Thirty days mortality was 1.8% (one patient).

CONCLUSIONS

PTRA results in kidney recipients are valuable mainly in preserving graft function.

Transplant renal artery stenosis: outcome after percutaneous intervention

PURPOSE

To assess the outcome of percutaneous transluminal angioplasty (PTA) and stent placement as the primary treatment for transplant renal artery stenosis (TRAS).

MATERIALS AND METHODS

A retrospective review of PTA and stent placement procedures performed for TRAS from April 1997 to July 2003 was conducted. Reviewed parameters included technical success, date of transplantation, dates of percutaneous intervention, mean arterial blood pressure, number of blood pressure medications, and serum creatinine level before and after intervention. Twenty-one interventions were performed in 18 allografts. The primary clinical indication for imaging and treatment was increased creatinine level in 12 allografts and hypertension in six allografts. Patency rates were estimated with use of the Kaplan-Meier method.

RESULTS

The technical success rate of PTA/stent placement was 100% and the clinical success rate was 94% (17 of 18 allografts). Thirteen interventions involved PTA alone, with eight combined PTA and stent insertions. The mean preintervention serum creatinine level among 12 allografts presenting with elevated creatinine levels was 2.8 mg/dL +/- 1.4 (SD), compared with a 1-month postintervention mean of 2.2 mg/dL +/- 0.7 (P = .03). Of six allografts that presented with hypertension, significant improvement was seen between the preintervention and 1-month postintervention mean systolic (174 mm Hg vs 135 mm Hg, P = .003) and diastolic (99 mm Hg vs 82 mm Hg, P = .02) pressures. These patients required a mean of 2.3 medications for blood pressure control before intervention, compared with a mean of 1.0 medications at 1 month after intervention (P = .002). Primary patency rates at 3, 6, and 12 months (+/-95% CI) were 94% +/- 6%, 72% +/- 12%, and 72% +/- 12%, respectively. Secondary patency rates at 3, 6, and 12 months (+/-95 CI) were 100%, 85% +/- 10%, and 85% +/- 10%, respectively. Mean follow-up time was 27 months. Of the eight allografts that underwent stent placement, all eight remained patent at last follow-up (mean, 18.3 months +/- 9.2). One major complication of a puncture site pseudoaneurysm occurred (5%).

CONCLUSION

Primary treatment of TRAS with PTA with or without stent placement has good intermediate-term patency and is associated with significant early improvement in blood pressure and creatinine level.

The role of interventional radiology in management of patients with end-stage renal disease

The aim of the paper is to review the role of interventional radiology in the management of hemodialysis vascular access and complications in renal transplantation. The evaluation of patients with hemodialysis vascular access is complex. It includes the radiology/ultrasound (US) evaluation of the peripheral veins of the upper extremities with venous mapping and the evaluation of the central vein prior to the access placement and radiological detection and treatment of the stenosis and thrombosis in misfunctional dialysis fistulas. Preoperative screening enables the identification of a suitable vessel to create a hemodynamically-sound dialysis fistula. Clinical and radiological detection of the hemodynamically significant stenosis or occlusion demands fistulography and endovascular treatment. Endovascular prophylactic dilatation of stenosis greater than 50% with associated clinical abnormalities such as flow-rate reduction is warranted to prolong access patency. The technical success rates are over 90% for dilatation. One-year primary patency rate in forearm fistula is 51%, versus graft 40%. Stents are placed only in selected cases; routinely in central vein after dilatation, in ruptured vein and elastic recoil. Thrombosed fistula and grafts can be declotted by purely mechanical methods or in combination with a lytic drug. The success rate of the technique is 89-90%. Primary patency rate is 8-26% per year and secondary 75% per year. The most frequently radiologically evaluated and treated complications in renal transplantation are perirenal and renal fluid collection and abnormalities of the vasculature and collecting system. US is often the method of choice for the diagnostic evaluation and management of the percutaneous therapeutic procedures in early and late transplantation complications. Computed tomography and magnetic resonance are valuable alternatives when US is inconclusive. Renal and perirenal fluid collection are usually treated successfully with percutaneous drainage. Doppler US, magnetic resonance angiography and digital subtraction angiography have a principle role in the evaluation of vascular complications of renal transplantation and management of the endovascular therapy. Stenosis, the most common vascular complication, occurs in 1-12% of transplanted renal arteries and represents a potentially curable cause of hypertension following transplantation and/or renal dysfunction. Treatment with percutaneous transluminal renal angioplasty (PTRA) or PTRA with stent has been technically successful in 82-92% of the cases, and graft salvage rate has ranged from 80 to 100%. Restenosis occurs in up to 20% of cases, but are usually amenable to repeated PTRA. Complications such as arterial and vein thrombosis are uncommon. Intrarenal A/V fistulas and pseudoaneurysms are occasionally seen after biopsy, the treatment requires superselective embolisation. Urologic complications are relatively uncommon, predominantly they consist of the urinary leaks and urethral obstruction. Interventional treatment consists of percutaneous nephrostomy, balloon dilation, insertion of the double J stents, metallic stent placement and external drainage of the extrarenal collections.

Early posttransplantation renal allograft perfusion failure due to dissection: diagnosis and interventional treatment

OBJECTIVE

The aim of our study was to describe the role of interventional radiology, especially in the use of vascular stents, in early renal perfusion failure after transplantation.

CONCLUSION

Angiography revealed intimal dissection of the graft artery and graft venous thrombosis, which were successfully treated with stent angioplasty and thromboaspiration. For early vascular complication after transplantation, timely use of angiography and subsequent intervention should be recognized as potentially effective and safe treatment techniques.

Surgical repair of transplant renal artery stenosis with preserved cadaveric iliac artery grafts

OBJECTIVE

To review the authors' experience with ABO-matched, preserved, cadaveric, iliac artery grafts for treatment of transplant renal artery stenosis (TRAS).

SUMMARY BACKGROUND DATA

TRAS is an important and treatable cause of hypertension and graft dysfunction in renal allograft recipients. Surgical treatment is reserved for lesions that are not amenable to percutaneous transluminal angioplasty (PTA) or for recurrence after PTA. Various surgical options for reconstruction of the transplant renal artery exist, although no single technique has been demonstrated to be superior. The authors have used preserved, blood type-matched, iliac artery grafts procured from cadaver organ donors to reconstruct transplant renal arteries in patients with specific lesions and following unsuccessful PTAs.

METHODS

Between 1991 and 2001, 21 patients underwent reconstruction of allograft renal arteries using cadaveric iliac artery as conduit. Charts, operative notes, and imaging studies of all patients were reviewed. A successful intervention for TRAS was defined as technical success as well as a decrease in serum creatinine and/or blood pressure 6 weeks after the procedure. Development of a hemodynamically significant lesion following renal artery reconstruction was considered a recurrence.

RESULTS

In patients treated with surgical reconstruction, hemodynamically significant TRAS occurred at or within 1 to 2 mm of the anastomosis in 13 patients, in the middle of the renal artery in 4, and secondary to a kink in 2 patients. Surgical treatment was undertaken in seven patients following unsuccessful PTA. Two patients had aneurysms of the iliac artery. Reconstruction using cadaveric iliac artery was successful in 19 of 21 (90%) patients, and only 1 these patients (4.8%) failed due to recurrence, with a median follow-up of 42 months. Graft loss secondary to TRAS occurred in two patients. The authors have not seen any long-term complications related to cadaveric iliac artery grafts, and the majority of the allografts continue to function well.

CONCLUSIONS

Surgical reconstruction of the transplant renal artery with blood type-matched iliac artery grafts should be considered a viable option for patients with specific anatomic lesions, those who have had an unsuccessful PTA, and those with recurrence following PTA.

Renal Arterial Stenosis in Renal Allografts: Retrospective Study of Predisposing Factors and Outcome after Percutaneous Transluminal Angioplasty

PURPOSE

To determine the predisposing factors to transplant renal arterial stenosis (TRAS) and assess the outcome of percutaneous transluminal angioplasty (PTA) as the primary treatment.

MATERIALS AND METHODS

Of 831 renal allograft recipients (584 cadaveric, 247 living related) between January 1991 and December 1998, 72 had hypertension and/or renal dysfunction. All 72 underwent arteriography, and their medical charts were retrospectively reviewed.

RESULTS

Prevalence of TRAS was 3.1% (26 of 831). Technical success rate of PTA was 94% (16 of 17), and clinical success rate was 82% (14 of 17). Those with renal dysfunction had a mean pre-PTA creatinine value of 2.6 mg/dL (230 micromol/L) +/- 0.5 (SD) versus a 1-week post-PTA value of 1.7 mg/dL (150 micromol/L) +/- 0.3 (P <.001). Of those with hypertension, all but one had substantial improvement in mean diastolic blood pressure. At 26.9 months mean follow-up in 16 patients with successful PTA, two stenoses reoccurred, and two grafts were lost to chronic rejection. TRAS was present in 14 of 45 end-to-side anastomoses and 12 of 27 end-to-end anastomoses (P =.31), and TRAS was more prevalent in cadaveric grafts (24 of 584) than in living related grafts (two of 247). In cadaveric grafts, the mean cold ischemia time was 29.0 hours +/- 6.9 in those with TRAS (n = 24), as compared with 25.5 hours +/- 8.1 in those with no TRAS (n = 39; P = .35). Seven of 17 patients with acute rejection and six of 35 with chronic rejection had TRAS.

CONCLUSION

Primary treatment of TRAS with PTA has good intermediate-term results. TRAS is more prevalent in cadaveric allografts with long cold ischemia time.

Angiographic evaluation and treatment of transplant renal artery stenosis

Transplant renal artery stenosis is an uncommon but important complication of renal transplantation. It is a potentially reversible cause of patient morbidity and allograft dysfunction, which can present both early and late in the post-transplant period. Although transplant renal artery stenosis can be detected using noninvasive imaging, definitive diagnosis and percutaneous treatment typically require the use of invasive angiographic techniques. In experienced hands, these studies can be performed safely, effectively and with a low risk of contrast induced nephrotoxicity when alternative contrast agents are used.

Dissection of an iliac artery conduit to liver allograft: treatment with an endovascular stent

Hepatic artery thrombosis remains one of the most serious complications after orthotopic liver transplantation. Sepsis, biliary leakage and strictures, and retransplantation are often the result of this devastating complication. Because retransplantation or reoperation is sometimes not possible or advisable, other means of reestablishing hepatic artery continuity are desirable. We describe a liver transplant recipient who developed a dissection of an iliac artery conduit after retransplantation that was treated with fibrinolytic therapy followed by successful placement of an endovascular stent.

Endoluminal stent placement after percutaneous transluminal angioplasty in the treatment of post-transplant renal artery stenosis

PURPOSE

We report our experience with endoluminal stent placement after percutaneous transluminal angioplasty for the treatment of post-transplant renal artery stenosis.

MATERIALS AND METHODS

From October 1992 to September 1996, 8 stents were successfully implanted in 7 patients affected by resistant transplant renal artery stenosis. All transplanted kidneys were procured from cadaver donors. The patients were routinely evaluated with duplex sonography and the median interval between transplantation and stenosis detection was 7.4 months (range 0.5 to 17). When serious renal stenosis was diagnosed (greater than 50%), selected angiography and percutaneous transluminal angioplasty were performed. In 8 cases (7 patients) an endoluminal metallic Palmaz stent was placed in the site of the restenosis. One patient received 2 stents repeatedly positioned in different stenosis sites.

RESULTS

No major complications occurred. Clinical outcome was positive in 5 patients (71.4%) and Stenosis recurred in 2 (28.5%) (less than 50% and less than 35%, respectively). Median followup after stent placement was 14.8 months (range 1 to 37).

CONCLUSIONS

Percutaneous endoluminal stent procedures after resistant transplant renal artery stenosis or for ex novo treatment for severe anastomotic stenoses appears to be promising. Longer followup periods are necessary for true evaluation of this procedure.

The use of expandable metal stents in transplant renal artery stenosis

The management of resistant transplant renal artery stenosis (TRAS) poses difficult problems. There is no consensus on the most appropriate course of action if severe stenosis recurs despite repeated percutaneous transluminal balloon angioplasty (PTA). Expandable metallic vascular stents have been increasingly successful as an adjunct to PTA in the coronary and peripheral circulation and more recently in the management of resistant native renal artery stenosis. We report four cases in which such stents were successfully used to treat resistant stenosis in transplant renal arteries. The cases illustrate the range of problems that may be caused by TRAS, from resistant hypertension to impending graft failure. The stents were successfully deployed in all four patients. One patient had an acute stent thrombosis successfully treated with immediate thrombolysis and two patients required repeat stenting. In all the cases there was arrest or slowing of previously aggressive recurrent TRAS and at the close of follow-up (4-24 months) all patients had adequate stable allograft function, and satisfactory blood pressure control including the one patient with a significant residual stenosis.

Treatment of renovascular hypertension with percutaneous transluminal angioplasty: experience in Spain

PURPOSE

The clinical results of percutaneous transluminal angioplasty (PTA) were evaluated in patients with renovascular hypertension, and the effect of PTA on blood pressure and renal function was determined.

PATIENTS AND METHODS

Between February 1982 and December 1990, 93 hypertensive patients underwent 123 renal artery PTA procedures. Mean patient age was 43.4 years (range, 12-78 years). Average baseline blood pressure was 162/111 mm Hg (range, 140-230/95-150 mm Hg). The cause of renovascular hypertension, as determined with angiography, was atherosclerosis in 37 patients, fibromuscular dysplasia in 27, and mixed disease in one; 28 patients had renal transplant arterial stenosis.

RESULTS

In patients with atherosclerotic renal vascular disease or fibromuscular renal artery stenosis, systolic and diastolic blood pressure decreased significantly (P < .001) at 96 months after PTA. In patients with renal transplant arterial stenosis, blood pressure also decreased significantly (P < .001) at 12 months after PTA. Technical success was achieved in 78% of patients with atherosclerosis, 92% of patients with fibromuscular dysplasia, and 76% of patients with renal transplants. Complications were seen in 4.8% and were related to renal failure and vessel dissection.

CONCLUSION

PTA is the therapy of choice in patients with renovascular hypertension due to fibromuscular dysplasia. Patients with atherosclerotic renal artery stenosis or stenosis of a renal artery in a transplanted kidney should be selected according to the anatomy of the lesion and clinical patient characteristics.

Renal allograft artery stenosis: results of medical treatment and intervention. A retrospective analysis

In a retrospective analysis of 1165 renal transplantations in our center, 65 cases of renal allograft artery stenosis were diagnosed angiographically (prevalence 5.5%). Hypertension was present in all cases; a bruit over the allograft and an increase in serum creatinine level were additional reasons for angiography. Shortly after diagnosis of the stenosis, two patients died and two others lost their grafts due to thrombosis. In 24 patients the decision was made not to correct the stenosis. One of these grafts was lost because the stenosis could not be corrected. Medical management of hypertension in these patients resulted in a decrease in diastolic blood pressure from 109 +/- 22 to 96 +/- 12 mm Hg (P < 0.01) 3 months after diagnosis with the use of almost twice as many antihypertensive drugs as at the time of diagnosis (P < 0.01). The stenosis was corrected if the angiography showed it to be so severe that it jeopardized renal allograft function or caused uncontrollable hypertension. Only three of nine percutaneous transluminal angioplasty (PTA) procedures resulted in a definitive correction of the stenosis. Surgical intervention was performed in 30 patients, including two patients whose PTAs had proved unsuccessful. Surgery led to graft loss due to thrombosis in 6 of 30 operations (20%), whereas restenosis occurred twice (7%). In three other cases (10%), the correction was not successful due to local anatomical variations or concomitant rejection.(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous transluminal angioplasty for transplant renal artery stenosis

A recent report has challenged the efficacy and safety of percutaneous transluminal angioplasty (PTA) for the treatment of transplant renal artery stenosis (TRAS). From January 1983 to December 1990, 24 PTA procedures were performed for TRAS in 18 patients. The stenoses were anastomotic in two cases, in the main renal artery in 14, and segmental in eight. After PTA, the residual stenosis was less than 20% in 14 (58%), 20%-50% in four (17%), and greater than 50% in six (25%). The mean diastolic blood pressure decreased from 106 mm Hg 1 day prior to PTA to 82 mm Hg 1 day after PTA. Long-term follow-up mean diastolic blood pressure (at 2-32 months) was 93 mm Hg (P less than .01). Eleven of the 18 patients (63%) had a 10% or greater reduction in diastolic blood pressure on long-term follow-up. Major complications occurred in two patients; one groin hematoma required surgical evacuation, and one polar infarct led to hypertension that was difficult to control. No surgical revisions of the transplant renal artery were necessary. The authors' data indicate that PTA should remain the treatment of choice for nonanastomotic TRAS.

Post-transplant renal artery stenosis: a possible immunological phenomenon

A retrospective review of 110 consecutive kidney transplants performed during 4 years revealed the development of renal artery stenosis in 9 patients (8.18%). A comparison of this group with a control group similar in patient age and interval elapsed since transplantation revealed no significant differences in donor and recipient ages, degree of HLA compatibility or serum creatinine levels. However, there was a significant difference in the number of acute rejection episodes. In our series only male patients were affected. A sizable proportion of the patients (50%) had no detectable murmur over the graft area despite high blood pressure and increased creatinine levels. The absence of surgical injury during extraction and implantation of the grafts, together with the anatomical site of the stenosis and correlation with the degree of immunological intolerance suggest an immunological factor as the underlying cause in post-transplant renal artery stenosis.

Transplant renal artery stenosis: experience and comparative results between surgery and angioplasty

One hundred thirty-eight patients with transplant renal artery stenosis (TRAS) were identified among 1200 patients undergoing renal transplantation in our university hospital. Severe systemic hypertension was the main symptom leading to a diagnosis of TRAS. Only 88 TRAS patients were given interventional treatment consisting of percutaneous angioplasty (PTA; n = 49) or surgical repair (SR; n = 39). The immediate success rate was 92.1% for SR and 69% for PTA. The long-term success rate was 81.5% for SR and 40.8% for PTA, with a follow-up period of 56.7 +/- 22.4 months (SR group) and 32 +/- 28.1 months (PTA group). PTA morbidity reached 28%, compared to 7.6% in the SR group. In spite of these results, we still favor PTA as a first line interventional treatment when TRAS is recent, linear, and distal and primary SR in cases of kinking and proximal TRAS.

Fibromuscular dysplasia in donor kidneys--experience with three cases

In 1987, three patients received kidney grafts bearing medial fibroplasia at our hospital. Two of the grafts were from a cadaveric donor and one was from a living related donor kidney. The vascular affection was known before transplantation. Only one of the recipients developed stenosis and hypertension. With balloon catheter dilatation, the progressive stenosis of the renal graft artery could, however, be successfully corrected.

Angioplasty of renal transplant artery stenosis in children

Systemic hypertension after renal transplantation in children is frequent, occurring in 85% of the cases and may be the cause of severe neurologic complications. This can be due to multiple factors such as: rejection, recurrence of initial disease, steroid, etc. ... Among those factors, renal transplant artery stenosis (RTAS) must be identified as it may be cured by angioplasty. We report our experience in 18 children who had undergone angioplasty for RTAS. Angioplasty was performed under general anesthesia with 3F, 4F or 5F balloon catheters. Angioplasty was successful in 14 cases (77%) immediately (10 cases), progressively (2 cases) or after a successfully redilated recurrence (2 cases). Two of the 4 failures were due to technical problems, a successful surgical treatment was then performed. The 2 others failures were explained by a severe transplant rejection. The complications were rare: 1 femoral artery thrombosis and spasms of the intra renal arteries but without repercussion on the renal function. In our experience, angioplasty seems to be the treatment of choice in RTAS in children. However the indications must be carefully established taking in account other possible causes of hypertension in such patients.

Unusual transplant renal angioplasty complication: case report

We report an avulsion of a transplant upper pole renal artery following apparently successful percutaneous transluminal angioplasty (PTA) of a stenosis involving main, upper, and lower pole renal arteries. We believe that the use of a high pressure balloon was the causative factor. If the branches at the bifurcation cannot be protected and if the stenoses fail to resolve under moderate balloon insufflation pressures (less than 5-6 atmospheres), consideration should be given to surgical revascularization.

Experience with percutaneous transluminal angioplasty for renal artery stenosis at the Cleveland Clinic

From April 1979 to June 1985 percutaneous transluminal angioplasty was attempted in 68 patients at our clinic to treat renovascular hypertension and/or to preserve renal function. The etiology of renal artery disease was atherosclerosis in 55 patients, fibrous dysplasia in 6, renal transplant arterial stenosis in 5 and postoperative saphenous vein graft stenosis in 2. A successful clinical outcome, defined as a decrease in blood pressure and/or improvement in renal function, was achieved in 12 patients (26.1 per cent) with atherosclerotic renal artery disease, 3 (75 per cent) with fibrous dysplasia, 2 (100 per cent) with saphenous vein graft stenosis and all 5 with transplant renal arterial stenosis (100 per cent). Improved results were observed in patients with nonostial atherosclerotic lesions compared to ostial lesions. There were 23 complications (33.8 per cent) after percutaneous transluminal angioplasty and all but 1 occurred with atherosclerosis. Of these complications 13 (19 per cent) were considered major. Since the beginning of 1983, however, only 3 complications occurred among 32 procedures (9.4 per cent) and only 1 of these was of major significance. When technically feasible, percutaneous transluminal angioplasty can provide effective treatment for selected patients with renal artery stenosis.

Renal transplantation in children

The application of the principles underlying successful renal transplantation in children has led us to increasing success in achieving our goals, which involve more than simple renal function replacement and include effective growth in stature, skeletal and central nervous system development, as well as social development. To succeed in these diverse areas, all modalities of therapy for ESRD may be needed at various times in some patients. Pretransplant therapy must be judiciously selected, and post-transplant protocols often modified to reflect individualized needs.

Arteriography of renal transplantation

The arterial anatomy of renal transplants is often complex, with overlapping, tortuous vessels which prevent easy visualisation of the origins of the transplant artery. We have adopted a technique using smallbore catheters with non-selective 'flush' injections of contrast medium, high resolution magnification techniques and multiple oblique projections. A retrospective study over six years (1980 to 1985 inclusive) revealed 34 significant (greater than 50%) transplant artery stenoses (13 adults, 21 children) from 200 transplant arteriograms performed. During this period, 452 transplants were performed, 38% in children. The incidence of transplant artery stenosis was 7.5%. Percutaneous transluminal angioplasty was attempted in 11 patients (four adults, seven children), with technical success in only five (45.5%). The predominance of children in this group contributes to the poor success rate of percutaneous transluminal angioplasty in our hands, which we attribute to the small arteries involved, the acute vessel angulations seen and the tough undilatable stenoses which are encountered in transplants in paediatric patients. Fourteen patients with post biopsy arterio-venous fistulae are described and the role of embolisation in this condition is discussed. A simplified approach for the arteriography of live related donors is also described.

Percutaneous transluminal angioplasty for renovascular hypertension in children

Percutaneous transluminal angioplasty (PTA) has been developed over the past 8 years as an alternative to reconstructive surgery for renovascular hypertension. We report three cases and review the use of PTA in children with renal artery stenosis. At least 37 cases of PTA have been reported in patients whose ages ranged from 1.3 to 17 years (mean 10 years). Of these, 10 had fibromuscular dysplasia; 13 unspecified unilateral renal artery stenosis; 4 bilateral stenosis; 4 neurofibromatosis; 4 renal transplant; 1 atherosclerosis; and 1 postsurgical stenosis. Nine of 10 patients with fibromuscular dysplasia were cured and 3 of 4 with renal transplant arterial stenosis were cured or improved. There were 11 failures of PTA, including all 4 patients with neurofibromatosis and 1 with transplant arterial stenosis. We conclude that PTA is the treatment of choice for children with hypertension due to fibromuscular dysplasia and should be attempted for stenosis of the transplanted renal artery. Other lesions resulting in renal artery stenosis may not be as amenable to dilation and should be considered on an individual basis.

Renal artery stenosis in pediatric transplant recipients

From 1967 through 1985, 400 cadaveric transplants were performed at Children Hospital of Los Angeles. Of these 400, 31 were later identified as having renal artery stenosis. No live related graft developed RAS. Of the 31 grafts, 11 were from donors less than 2 years of age. The major feature suggesting stenosis was hypertension; either persistent or a sudden exacerbation often associated with hypertensive encephalopathy. In individuals with hypertension without obvious cause, renal angiography should be promptly conducted under controlled conditions to avoid complications. The stenotic lesion involved 13 end-to-end and 19 end-to-side arterial anastomoses. Surgery for revascularization of RAS was performed in 21 of 31 with success or improvement in 14, no change in 2, and graft loss in 5. Percutaneous transluminal angioplasty was performed in 4. Two were unsuccessful, 1 was successful and 1 graft was lost. The 7 remaining patients were treated medically.