Kidney transplant artery and vein stenting: 15-year follow-up.

BACKGROUND: We would like to present an unusual case of simultaneous stenosis of renal graft artery and vein diagnosed four months after transplantation. both treated by stent placement. Our aim is to point at the fact that renal graft venous stenosis is very rarely reported in the literature and - as it is not easy to diagnose by routine US - it could be overlooked. If early detected it can be treated by stent placement. CASE PRESENTATION: We present a case of 36-old-male with renal failure who received a kidney graft from deceased donor. The patient experienced delayed graft function. No rejection was found in the biopsy. Four months after transplantation the kidney function deteriorated to sCr 280 µmol/l. Graft artery stenosis together with graft vein stenosis was revealed. Both lesions were dilated with stent placement, the graft function returned to 230 µmol/l and became stable for 10 years. Ten years after stent placement graft function deteriorated to 300 µmol/l. An in stent restenosis of arterial stent was detected. It was successfully dilated by the balloon, the graft function returned to 230 µmol/l and stays stable for another 5 years. CONCLUSIONS: An unusual simultaneous transplanted kidney artery and vein stenosis treated by stent placement is presented. The patient had stable graft function for 15 years after the procedure with one re-intervention on arterial stent.

Correction to: Interventional Radiological Treatment of Pediatric Liver Transplantation Complications.

In the original article, the following author name was incorrectly published and the corrected name is given below.

Interventional Radiological Treatment of Paediatric Liver Transplantation Complications.

PURPOSE: To assess the efficacy of percutaneous techniques in managing paediatric liver transplantation complications. MATERIAL AND METHODS: We carried out 105 paediatric cadaveric donor liver transplantations at our centre from 2001 to 2018. Percutaneous techniques were used to treat 25 cases involving transplantation complications in 23 patients. Biliary complications were treated in 14 cases (13.3%): 10 patients had bile duct obstruction, and 4 had biliary leaks. Vascular complications were treated in 11 cases (10.5%): 5 hepatic artery (HA) stenoses/occlusions, 2 inferior vena cava (IVC) stenoses, and 1 portal vein (PV) stenosis. Other interventions involved embolisation of the superior mesenteric artery branch to manage gastrointestinal bleeding in 2 patients and embolisation of an arteriobiliary fistula in 1 patient. RESULTS: Biliary: We carried out external-internal drainage and balloon dilatation of stenoses in 12 cases. The external-internal drainage catheter was removed after 6-8 weeks in 7 patients, with the remaining 5 patients with persisting stenosis assigned for retransplantation. We failed to cross anastomotic occlusions in 2 patients before completing the procedures using external drainage; both individuals subsequently underwent retransplantation. Vascular: We performed PTA/stenting of HA stenoses/occlusions in 4 out of 5 patients. After the procedure, all 4 patients showed liver function normalisation. All 3 cases of embolisation were technically and clinically successful. Both IVC and PV stenoses treated with dilatation/stenting were also successful. CONCLUSIONS: Percutaneous techniques used to treat biliary and vascular complications after liver transplantation in paediatric patients are safe and efficient.

Executive summary of the joint position paper on renal denervation of the Cardiovascular and Interventional Radiological Society of Europe and the European Society of Hypertension.

Renal denervation (RDN) was reported as a novel exciting treatment for resistant hypertension in 2009. An initial randomized trial supported its efficacy and the technique gained rapid acceptance across the globe. However, a subsequent large blinded, sham arm randomized trial conducted in the USA (to gain Food and Drug Administration approval) failed to achieve its primary efficacy end point in reducing office blood pressure at 6 months. Published in 2014 this trial received both widespread praise and criticism. RDN has effectively stopped out with clinical trials pending further evidence. This joint consensus document representing the European Society of Hypertension and the Cardiovascular and Radiological Society of Europe attempts to distill the current evidence and provide future direction and guidance.

Comparison of the effect of stem cell therapy and percutaneous transluminal angioplasty on diabetic foot disease in patients with critical limb ischemia.

BACKGROUND AIMS: The aim of our study was to compare the effect of autologous stem cell therapy (SCT) and percutaneous transluminal angioplasty (PTA) on diabetic foot disease (DFD) in patients with critical limb ischemia (CLI). METHODS: Thirty-one patients with DFD and CLI treated by autologous stem cells and 30 patients treated by PTA were included in the study; 23 patients with the same inclusion criteria who could not undergo PTA or SCT formed the control group. Amputation-free survival, transcutaneous oxygen pressure (TcPO2) and wound healing were assessed over 12 months. RESULTS: Amputation-free survival after 6 and 12 months was significantly greater in the SCT and PTA groups compared with controls (P = 0.001 and P = 0.0029, respectively) without significant differences between the active treatment groups. Increase in TcPO2 did not differ between SCT and PTA groups until 12 months (both Ps < 0.05 compared with baseline), whereas TcPO2 in the control group did not change over the follow-up period. More healed ulcers were observed up to 12 months in the SCT group compared with the PTA and control groups (84 versus 57.7 versus 44.4 %; P = 0.042). CONCLUSIONS: Our study showed comparable effects of SCT and PTA on CLI, a major amputation rate that was superior to conservative therapy in patients with diabetic foot and an observable effect of SCT on wound healing. Our results support SCT as a potential promising treatment in patients with CLI and diabetic foot.

Nephrostomy in early posttransplantation period in patients with nonfunctional graft and nondilated collecting system.

BACKGROUND: The purpose of our study was to determine whether renal function can be restored by early nephrostomy in patients who fail to develop renal function immediately after transplantation. METHODS: Between 2001 and 2010, we have performed external/internal nephrostomy in 13 patients during the early posttransplant period. The reason for the procedure was graft nonfunction with oliguria/anuria in the presence of normal renal perfusion, absence of signs of rejection, and/or renal collecting system dilation. The nephrostomy was created under ultrasound/fluoroscopic guidance. RESULTS: Nephrostomy was technically successful in all cases. On days 1-3 following nephrostomy creation, 10 of 13 patients showed an increase in diuresis and subsequent graft function development. Once the obstruction had been removed, the graft remained functional for months up to years posttransplantation. Three patients failed to respond to nephrostomy. There were no nephrostomy-related complications. CONCLUSIONS: Our study documents that, in patients who failed to develop graft function posttransplant for unknown reasons, nephrostomy may result in graft function development.

Manometric perfusion test in biliary strictures treatment.

BACKGROUND/AIMS: To assess the biliary manometric perfusion test (BMPT) for evaluating success in treating benign biliary strictures. METHODOLOGY: During 2003 to 2010, 29 patients were subjected to BMPT after percutaneous balloon dilatation treatment. Intrabiliary pressure less than 20cm of water was considered the success threshold. Results of BMPT evaluation were retrospectively compared with a similar group where the standard clinical test was used for evaluating treatment success. The clinical test group included 21 patients treated for biliary strictures from 1994 to 2006. RESULTS: The two groups were statistically similar by age and gender. The BMPT group was tested without complications and pressure inside the biliary tree was less than 20cm of water in 27 of 29 patients. Subsequently, catheters were removed from all 27. Three patients required re-interventions 13 days, 11 months and 32 months later. Kaplan-Meier survival analysis showed that the probability of biliary patency at 3 year was 82.2%. There was no significant difference between groups by this measure (log rank test, p=0.624). CONCLUSIONS: The manometric test is an alternative for evaluating success in treating benign biliary strictures. It is simple, less time-consuming, economical, safe, effective and more comfortable for patients than the clinical test.

Twin valve caval stent for functional replacement of incompetent tricuspid valve: a feasibility animal study.

OBJECTIVE: To evaluate feasibility of a twin valve caval stent (TVCS) for functional replacement of an incompetent tricuspid valve (TV) in an acute animal study. METHODS: One swine and three sheep were used in the study. TVCS placement was tested in a swine with a normal TV. TVCS function was tested in three sheep with TV regurgitation created by papillary muscle avulsion. Cardiac angiograms and pressure measurements were used to evaluate TVCS function. Two sheep were studied after fluid overload. RESULTS: TVCS was percutaneously placed properly at the central portions of the superior vena cava (SVC) and inferior vena cava (IVC) in the swine. Papillary muscle avulsion in three sheep caused significant tricuspid regurgitation with massive reflux into the right atrium (RA) and partial reflux into the SVC and IVC. TVCS placement eliminated reflux into the SVC and IVC. After fluid overload, there was enlargement of the right ventricle and RA and significant increase in right ventricle, RA, SVC, and IVC pressures, but no reflux into the IVC and SVC. CONCLUSION: The results of this feasibility study justify detailed evaluation of TVCS insertion for functional chronic replacement of incompetent TV.

N-acetylcysteine attenuates iodine contrast agent-induced nephropathy in 5/6-nephrectomized rats.

AIMS: In the present study we tested the efficacy of N-acetylcysteine (NAC) to minimize nephrotoxic effects of iodine contrast agents in intact rats as well as in 5/6-nephrectomized (5/6-Nx) rats. METHODS: Rats were allocated to a group of intact rats (n = 42) and a group of 5/6-Nx rats (n = 42). After 1 month of recovery from surgery, 5/6-Nx rats and intact (sham-operated) animals received either 6 ml/kg body weight (b.w.) meglumine ioxithalamate (Telebrix 350) or 6 ml/kg b.w. iohexol (Omnipaque 350) intravenously with or without pretreatment with 100 mg/kg b.w. NAC. Plasma and urinary concentrations of creatinine, sodium and protein in 24-hour urine collections were determined prior to and on days 1, 3 and 7 after drug administration. RESULTS: In intact animals, contrast agents caused no significant changes in kidney function throughout the duration of the experiment. In contrast, significant increases in plasma creatinine levels and decreases in creatinine clearance were induced by both contrast agents in 5/6-Nx rats. These changes were significantly attenuated by NAC pretreatment. CONCLUSION: The results of the present study demonstrate that iodine contrast agent-induced nephropathy in 5/6-Nx rats is significantly attenuated by intravenous pretreatment with NAC.

PTA of infrapopliteal arteries: long-term clinical follow-up and analysis of factors influencing clinical outcome.

This study was a retrospective analysis of patients with CLI who underwent infrapopliteal percutaneous transluminal angioplasty (PTA). The main goal was to evaluate clinical and morphological factors that influence the clinical outcome of PTA in long-term follow-up. A total of 1,445 PTA procedures were performed in 1,268 patients. Main indications for PTA included gangrene, nonhealing ulcers, or rest pain. The mean number of treated arteries was 1.77 artery/limb, and the majority of lesions were type TASC D. The technical success rate of PTA was 89% of intended-to-treat arteries. The main criterion of clinical success was functional limb salvage (LS). One-year follow-up involved 1,069 limbs. Primary and secondary 1-year LS rates were 76.1 and 84.4%, respectively. The effect of clinical and morphological parameters on the 1-year LS was that the only associated disease with an adverse effect on LS rate was DM combined with dialysis. Regarding limb preprocedural status, gangrene was clearly a negative predictor. The most important factor affecting LS was the number of patent arteries post-PTA: patients with 0, 1, 2, and 3 patent arteries had 1-year primary LS rates of 56.4, 73.1, 80.4, and 83%, respectively. Long-term follow-up of LS rates demonstrated secondary LS rates of 84.4, 78.8, and 73.3% at 1, 5, and 10 years. Every effort should be made to perform PTA for as many arteries as possible, even if TASC D type, to improve clinical outcome. Our study shows that repeat PTA is capable of keeping the long-term LS rate close to 75%.

Treatment of venous aortorenal bypass graft aneurysm using a stent-graft.

We present the case of a 77-year-old male patient who had undergone a bilateral venous aortorenal bypass graft 30 years previously. Thirteen years previously, the patient was shown to have a decrease in renal function, with mild shrinking of both kidneys; additionally, a stenosis was found in the left proximal anastomosis. At the most recent follow-up visit (1 year previously), ultrasound revealed an aneurysm (42 mm in diameter) of the left renal bypass graft; the finding was confirmed by CT angiography. A significant ostial stenosis of the left renal bypass graft was also confirmed. It was decided to place a self-expandable stent-graft into the aneurysm while also attempting to dilate the stenosis. Proximal endoleak after stent-graft placement necessitated the implantation of another, balloon-expandable stent-graft into the bypass graft ostium. Postprocedural angiography and follow-up by CT angiography at 3 months confirmed good patency of the stent-grafts and complete thrombosis of the aneurysmal sac, with preserved kidney perfusion. Renal function remained unaltered, while the hypertension is better controlled.

A new cone-shaped aortic valve prosthesis for orthotopic position: an experimental study in Swine.

The aim of this experimental study was to evaluate a newly designed cone-shaped aortic valve prosthesis (CAVP) for one-step transcatheter placement in an orthotopic position. The study was conducted in 15 swine using either the transcarotid (11 animals) or the transfemoral (4 animals) artery approach. A 12- or 13-Fr sheath was inserted via arterial cutdown. The CAVP was deployed under fluoroscopic control and its struts, by design, induced significant native valve insufficiency. CAVP function was evaluated by aortography and aortic pressure curve tracing. In 11 of 15 swine the CAVP was properly deployed and functioned well throughout the scheduled period of 2-3 h. In three swine the CAVPs were placed lower than intended, however, they were functional even in the left ventricular outflow tract position. One swine expired due to inadvertent low CAVP placement that caused both aortic regurgitation and immobilization of the anterior mitral valve leaflet by the valve struts. We conclude that this design of CAVP is relatively easy to deploy, works well throughout a short time period (2-3 h), and, moreover, seems to be reliable even in a lower-than-orthotopic position (e.g., infra-annulary space). Longer-term studies are needed for its further evaluation.

Effect of intravascular iodinated contrast media on natural course of end-stage renal disease progression in hemodialysis patients: a prospective study.

We evaluated the impact of intravascular iodinated contrast medium on residual diuresis in hemodialyzed patients. Two groups of clinically stable hemodialyzed patients with residual diuresis minimally 500 ml of urine per day were studied. The patients from the first group were given iso-osmolal contrast agent iodixanol (Visipaque, GE Healthcare, United Kingdom) in concentration of iodine 320 mg/ml with osmolality 290 mOsm/kg of water during the endovascular procedure. The second control group was followed without contrast medium administered. Residual diuresis and residual renal excretory capacity expressed as 24-h calculated creatinine clearance were evaluated in the both groups after 6 months. The evaluated group included 42 patients who were given 99.3 ml of iodixanol in average (range, 60-180 ml). The control group included 45 patients. There was no statistically significant difference found between both groups in daily volume of urine (P = 0.855) and calculated clearance of creatinine (P = 0.573). We can conclude that residual diuresis is not significantly influenced by intravascular administration of iso-osmolal iodinated contrast agent (iodixanol) in range of volume from 60 to 180 ml in comparison to natural course of urinary output and residual renal function during end-stage renal disease. This result can help the nephrologist to decide which imaging method/contrast medium to use in dialyzed patients in current practice.

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.

Primary self-expandable nitinol stent placement in focal lesions of infrarenal abdominal aorta: long term results.

PURPOSE: To evaluate the technical and clinical success, safety and long term results of percutaneous transluminal angioplasty/self-expandable nitinol stent placement of infrarenal abdominal aorta focal lesions. MATERIALS AND METHODS: Eighteen patients underwent PTA of focal atherosclerotic occlusive disease of distal abdominal aorta. Two symptomatic occlusions and 16 stenoses in 10 male and 8 female patients (mean age 68.2 years) were treated with primary self-expandable nitinol stent placement. RESULTS: Primary self-expandable nitinol stent placement was technically successful in all 18 procedures; clinical success was achieved in 100% of patients. No complications associated with the procedure occurred. During the 49.4 months of mean follow up (range 3-96, 4 months) all treated aortic segments remained patent. CONCLUSIONS: Endovascular treatment (primary self-expandable nitinol stent placement) of focal atherosclerotic lesions of distal abdominal aorta is a safe method with excellent primary technical and clinical success rates and favourable Long term results.

Catheter-based modification of heart valve diseases: from experimental to clinical application.

Efforts to modify cardiac valve defects using catheter-based techniques are increasing at the present time. We present observations on cardiac valve morphology and disease and review the progress being made to address valve defects with these innovative methods. Some new procedures developed through animal experimentation have already been put to use in clinical practice, but the newness of these techniques and the small number of cases in which they have been applied to date precludes an evaluation of their long-term durability. Although at the present time cardiac surgery remains the standard for treating most cases of valve disease, in certain situations a catheter-based treatment might provide a reasonable alternative, even if only temporary, especially for individuals with serious disease who are not suitable candidates for surgery.

Potential use of a combined extractor in intravascular procedures.

Extraction techniques are gaining increasing attention in proportion to the increasing range of endovascular procedures. The choice of the instrumentarium depends, among other things, on whether the object to be extracted is a foreign body (most often a catheter) with or without a free end. This communication offers our experience with a combined extractor of our own manufacture allowing both central and lateral grasping techniques. The technique of catheterization is illustrated in one case.

Results of a peripheral cutting balloon prospective multicenter European registry in hemodialysis vascular access.

PURPOSE: To report initial experience with the Peripheral Cutting Balloon (PCB) in treatment of failing hemodialysis shunts. METHODS: A total of 190 patients (95 men, 95 women; average age 64.4 +/- 11.9 years, range 32-87 years) who were treated with the PCB for pressure-resistant stenosis, restenosis or failed percutaneous transluminal angioplasty (PTA) in the venous limb of an arteriovenous shunt were followed in seven European centers using a simple registry. The group consisted of 109 de novo lesions (57%) and 79 restenotic lesions (43%). RESULTS: Technical success was achieved in 88.9% of cases. Primary patency was as follows (the results for whole group and simultaneous results for de novo lesions and restenoses are presented): 1 month (140 patients followed): 94%, 98%, and 93%; 3 months (116 patients followed): 93%, 98%, and 92%; 6 months (40 patients followed): 85%, 92%, and 79%; 12 months (27 patients followed): 74%, 87%, and 48%. No complication occurred. Patients experienced an equal or lower level of pain during the procedure compared with conventional PTA. CONCLUSION: The PCB proved to be successful in dilating pressure-resistant stenoses. We cannot conclude whether PCB angioplasty can lower the restenosis rate in hemodialysis access lesions, but the long-term patency for de novo lesions is high. A further randomized study is advisable.

Percutaneous transcatheter one-step mechanical aortic disc valve prosthesis implantation: a preliminary feasibility study in swine.

PURPOSE: To evaluate the feasibility of one-step implantation of a new type of stent-based mechanical aortic disc valve prosthesis (MADVP) above and across the native aortic valve and its short-term function in swine with both functional and dysfunctional native valves. METHODS: The MADVP consisted of a folding disc valve made of silicone elastomer attached to either a nitinol Z-stent (Z model) or a nitinol cross-braided stent (SX model). Implantation of 10 MADVPs (6 Z and 4 SX models) was attempted in 10 swine: 4 (2 Z and 2 SX models) with a functional native valve and 6 (4 Z and 2 SX models) with aortic regurgitation induced either by intentional valve injury or by MADVP placement across the native valve. MADVP function was observed for up to 3 hr after implantation. RESULTS: MADVP implantation was successful in 9 swine. One animal died of induced massive regurgitation prior to implantation. Four MADVPs implanted above functioning native valves exhibited good function. In 5 swine with regurgitation, MADVP implantation corrected the induced native valve dysfunction and the device's continuous good function was observed in 4 animals. One MADVP (SX model) placed across native valve gradually migrated into the left ventricle. CONCLUSION: The tested MADVP can be implanted above and across the native valve in a one-step procedure and can replace the function of the regurgitating native valve. Further technical development and testing are warranted, preferably with a manufactured MADVP.