Branch Of Renal Artery Research Articles

Extracorporeal resection of renal artery aneurysm and separate autogenous vein graft repair of its branches in a patient with retroaortic renal vein

Autopsy and intravital studies have reported the incidence of renal artery aneurysms (RAA) in 0.01 to 0.97% of the population. Fibromuscular dysplasia (FMD) and atherosclerosis are the main etiological factors for the development of RAA. The presence of abnormalities of the veins such as a retroaortic renal vein can significantly complicate the implementation of surgical interventions. The main methods to treat RAA are RAA resection with prosthetic repair, embolization of aneurysm cavities, and placement of an endograph. When aneurysm spreads to involve the renal artery branches or RAA is located in the kidney gates, the extracorporeal renal artery reconstruction is the only method to restore the renal vessels and keep a kidney. The article provides a rare observation of a patient suffering from renal artery fibromuscular dysplasia, left renal artery aneurysm with the development of vasorenal hypertension. The features of this clinical observation were the retroaortic left renal vein and the renal artery aneurysm located in the kidney gates. The patient underwent ureter-sparing extracorporeal autogenous vein graft repair of left renal artery branches. The surgery was performed using custodial solution for kidney pharmaco-hypothermic protection. Renal artery aneurysm was resected with the creation of a common junction of the renal artery branches followed by autogenous vein graft repair. The two lower segmental branches of the renal artery were separately prosthetized using the reversed autovein sections. Parietal injury to the left ureter was diagnosed in the patient in the postoperative period. A percutaneous needle-guided urine drainage bag was superimposed under ultrasound guidance with the placement of an integral stent in the injury area. The patient was discharged to outpatient care on Day 11. The urine drainage bag was removed two months after the control CTA. The integral stent was removed a month later, normal urine output was restored in the upper urinary tract. After 6 months, the control CTA showed that all reconstructed renal artery branches were completely patent, and blood pressure readings were within normal range.

Left Bifid Ureter and Renal Artery Variation in an Adult Female Cadaver

During the retroperitoneal space dissection of a 77‐year‐old female cadaver, a left duplicated ureter (DU) was observed along with variations of left renal artery branching pattern. The ureter, typically 25–30cm in length, is a continuation of the renal pelvis that receives filtrate from 2 or 3 major calyces before entering the bladder. In this cadaver, two separate ureters that drained upper and lower kidney, with lengths of 12.4 cm and 10.6 cm respectively. The two ureters then joined to form a common ureter with a length of 12.7 cm before entering the bladder. There are two types of DU; this type of DU has been previously described as an incomplete or bifid ureter and is a commonly asymptomatic congenital abnormality of the kidney and urinary tract (CAKUT). However, it can produce symptoms of frequent urinary tract infections, urinary lithiasis, ureteric stenosis and renal colic (1). The incidence of any type of DU is 1 in 100 to 1 in 500 (2) and is also more common in women than men, with a ratio of 2:1 (1). Unusual blood supply of the left kidney was also observed with an aberrant left renal artery arising from the abdominal aorta 4 cm inferior to the left renal artery, crossing anterior to the DU and supplying the lower pole of the left kidney. The ovarian artery was observed arising from this aberrant left renal artery. The incidence of the gonadal artery arising from a source other than the abdominal aorta is approximately 20% (3). The incidence of an aberrant renal artery is observed in 20–30% of the population and has the potential to result in hydronephrosis (4).Support or Funding Information

The Role of MDCT Angiography in Preoperative Evaluation of the Living Renal Donors

Abstract Background: Renal transplantation is the treatment of choice for patients with end stage renal disease. The transplant surgeon needs accurate preoperative data about the anatomy of renal vasculature to reduce the hazards associated with the procedure. MDCTA is used because it is less invasive, simply appropriate and accessible. It allows accurate imaging of the normal and variant anatomy of the renal vasculature. Aim of Study: To investigate the role of multidetector computed tomography angiography (MDCTA) in evaluating the preoperative anatomy of the renal vasculature in potential renal donors. Subjects and Methods: A total of 30 patients underwent MDCTA as a routine work-up for live renal donors. The number of branches of renal arteries and veins, together with the frequency of incidental findings of the renal parenchyma were assessed. Multiplanar reformations, maximum intensity projections, and volume renderings were used. The results gained were surgically correlated. Results: We recognized surgically important vascular variants and renal parenchymal abnormalities. Eight of 30 (27%) subjects were excluded based on the MDCTA findings, due to vascular causes in 4 cases, recipient death in 2 cases, renal stones in one case, and a horse-shoe kidney in one case. The surgical decision of right nephrectomy was made in one case (4.5%) due to complex vascular anatomy on the left side identified on MDCTA. The surgically established sensitivities of MDCTA data for the detection of the renal arteries and veins were 100% and 95.5%, respectively. Conclusion: MDCTA correctly detected essential exclu-sions for renal donation and aided the choice of the preferred kidney to be harvested based on parenchymal and va scular findings.

In Reply: The Safety and Efficacy of Continuous Tirofiban as a Monoantiplatelet Therapy in the Management of Ruptured Aneurysms Treated Using Stent-Assisted Coiling or Flow Diversion and Requiring Ventricular Drainage.

Background Hemorrhagic complications are a major concern for aneurysmal subarachnoid hemorrhage patients treated with stenting or stent-assisted coiling and undergoing additional procedures such as shunting, ventriculostomy placement, and craniotomies/craniectomies. Objective To assess the safety and efficacy of using a continuous infusion of tirofiban as a monoantiplatelet therapy in the management of ruptured aneurysms in the setting of either stent-assisted coiling (SAC) or flow diversion devices (FDD) in patients requiring either an external ventricular drain (EVD) or ventriculoperitoneal shunt (VPS). Methods Aneurysmal subarachnoid hemorrhage (aSAH) patients between July 2017 and September 2018 who were treated with SAC or FDD were started on a continuous tirofiban infusion protocol (0.10 μg/kg/min) with no preceding loading dose as a monoantiplatelet therapy. Safety analysis was performed retrospectively to assess the complication rate, hemorrhagic rate, and rate of ischemic events. There were no hemorrhages related to the VPS surgery. Results Nineteen subjects were included in the series. The patients received a total of 25 procedures that included 19 EVDs and 6 VPSs. Two patients (8.3%) developed small asymptomatic track hemorrhages after EVD placement. One patient developed a large retroperitoneal hemorrhage due to renal artery branch injury during procedure, and another patient developed an idiosyncratic transient thrombocytopenia which resolved after stopping the medication. One patient (4%) developed a transient ischemic attack, which resolved after a bolus of tirofiban. Conclusion Our study suggests that long-term use of intravenous tirofiban monotherapy in aSAH subjects for endovascular SAC or FDD is safe in the perioperative setting.

In Situ Treatment of Branch Renal Artery Aneurysms With Pantaloon Vein Graft.

The optimal method of operative management of complex renal artery aneurysms (RAAs) involving distal branches (BRAAs) remains unclear. When more than 1 artery is involved within the BRAA, endovascular techniques are not advisable and an ex vivo approach is often preferred. In this study, we introduce an alternative surgical in situ technique to treat BRAAs. Five aneurysms involving the main or second-order bifurcation of the renal artery (RA) were treated in 4 patients at our institute between November 2012 and January 2017. The treatment of the BRAAs was based on resection of the aneurysm wall and reconstruction with autologous Pantaloon vein graft (PVG): a "Y-shaped" bypass created on-bench with autogenous great saphenous vein. Sequential clamping/reperfusion of the kidney allows to reduce renal function impairment. No perioperative mortality or morbidity was observed, including none nephrectomy. In all the cases, aneurysms were treated with an in situ technique as previously planned. All the grafts were patent at the follow-up time (mean 64.1 ± 11.7 months). Renal function was preserved in all the cases. Vascularization of the renal parenchyma was satisfactory both on arterial echo Doppler and contrast-medium ultrasound in all the cases. Average cross-clamping times of the main RA and of a single branch RA were 15.8 ± 1.7 and 17.7 ± 4.6 minutes, respectively. Mean total operating time was 266.3 ± 18.9 minutes. The PVG with sequential clamping applied in the surgical treatment of BRAAs permits to reduce the ischemic effects to the renal parenchyma. To our knowledge, these are the first cases described in which BRAAs are treated with a PVG and our experience suggests that it is a feasible technique, with good long-term results and without severe adverse events recorded.

Management of Renal Arteries in Conjunction with Thoracic Endovascular Aortic Repair for Complicated Stanford Type B Aortic Dissection: The Japanese Multicenter Study (J-Predictive Study).

Background Management of abdominal branches associated with Stanford type B aortic dissection is controversial without definite criteria for therapy after thoracic endovascular aortic repair (TEVAR). This is in part due to lack of data on natural history related to branch vessels and their relationship with the dissection flap, true lumen, and false lumen. Purpose To investigate the natural history of abdominal branches after TEVAR for type B aortic dissection and the relationship between renal artery anatomy and renal volume as a surrogate measure of perfusion. Materials and Methods This study included patients who underwent TEVAR for complicated type B dissection from January 2012 to March 2017 at 20 centers. Abdominal aortic branches were classified with following features: patency, branch vessel origin, and presence of extension of the aortic dissection into a branch (pattern 1, supplied by the true lumen without branch dissection; pattern 2, supplied by the true lumen with branch dissection, etc). The branch artery patterns before TEVAR were compared with those of the last follow-up CT (mean interval, 19.7 months) for spontaneous healing. Patients with one kidney supplied by pattern 1 and the other kidney by a different pattern were identified, and kidney volumes over the course were compared by using a simple linear regression model. Results Two hundred nine patients (mean age ± standard deviation, 66 years ± 13; 165 men and 44 women; median follow-up, 18 months) were included. Four hundred fifty-nine abdominal branches at the last follow-up were evaluable. Spontaneous healing of the dissected branch occurred in 63% (64 of 102) of pattern 2 branches. Regarding the other patterns, 6.5% (six of 93) of branches achieved spontaneous healing. In 79 patients, renal volumes decreased in kidneys with pattern 2 branches with more than 50% stenosis and branches supplied by the aortic false lumen (patterns 3 and 4) compared with contralateral kidneys supplied by pattern 1 (pattern 2 vs pattern 1: -16% ± 16 vs 0.10% ± 11, P = .002; patterns 3 and 4 vs pattern 1: -13% ± 14 vs 8.5% ± 14, P = .004). Conclusion Spontaneous healing occurs more frequently in dissected branches arising from the true lumen than in other branch patterns. Renal artery branches supplied by the aortic false lumen or a persistently dissected artery with greater than 50% stenosis are associated with significantly greater kidney volume loss. © RSNA, 2019 Online supplemental material is available for this article.

The Safety and Efficacy of Continuous Tirofiban as a Monoantiplatelet Therapy in the Management of Ruptured Aneurysms Treated Using Stent-Assisted Coiling or Flow Diversion and Requiring Ventricular Drainage.

Hemorrhagic complications are a major concern for aneurysmal subarachnoid hemorrhage patients treated with stenting or stent-assisted coiling and undergoing additional procedures such as shunting, ventriculostomy placement, and craniotomies/craniectomies. To assess the safety and efficacy of using a continuous infusion of tirofiban as a monoantiplatelet therapy in the management of ruptured aneurysms in the setting of either stent-assisted coiling (SAC) or flow diversion devices (FDD) in patients requiring either an external ventricular drain (EVD) or ventriculoperitoneal shunt (VPS). Aneurysmal subarachnoid hemorrhage (aSAH) patients between July 2017 and September 2018 who were treated with SAC or FDD were started on a continuous tirofiban infusion protocol (0.10 μg/kg/min) with no preceding loading dose as a monoantiplatelet therapy. Safety analysis was performed retrospectively to assess the complication rate, hemorrhagic rate, and rate of ischemic events. There were no hemorrhages related to the VPS surgery. Nineteen subjects were included in the series. The patients received a total of 25 procedures that included 19 EVDs and 6 VPSs. Two patients (8.3%) developed small asymptomatic track hemorrhages after EVD placement. One patient developed a large retroperitoneal hemorrhage due to renal artery branch injury during procedure, and another patient developed an idiosyncratic transient thrombocytopenia which resolved after stopping the medication. One patient (4%) developed a transient ischemic attack, which resolved after a bolus of tirofiban. Our study suggests that long-term use of intravenous tirofiban monotherapy in aSAH subjects for endovascular SAC or FDD is safe in the perioperative setting.

Variations of Renal Artery in Cadavers

Each kidney is usually supplied by a single renal artery which is a lateral branch of abdominal aorta at the level of L1.The arteries supplying the kidneys show variation in the number, source and branching pattern which also include the presence of an accessory or additional and aberrant renal arteries. The additional renal artery towards the lower pole will cross the corresponding ureter and even cause ureteric obstruction. The segmental branches of renal and additional renal arteries are end arteries thus the accidental damage to these arteries can cause ischemia or necrosis and other pathological conditions. The main objective of this study was to note the variations of the arteries supplying the kidneys. An observational study was conducted on thirty kidneys of fifteen cadavers which included the kidneys of both sides. The study was conducted in Department of Anatomy of Nepal Medical College Teaching Hospital during the period between July 2018 to June 2019 and the variations were recorded as (a) single main renal arteries were found in 80% specimens on both sides (b) early division of main renal arteries were found in 16.66 % on both sides (c) origin of main renal arteries were at higher level on left side in 16.66 % (d) presence of additional renal arteries were found in 20% on both sides. This study will be helpful to cryosurgeons and also to radiologists performing various interventional radiological procedures.

Renal artery variations: a 20.782 kidneys review.

Introduction: vascular anatomy variations are important in academic, clinical and surgical areas as well as nephrology, urology, oncological and vascular surgery, among others. The main objective of this review is to know the real prevalence of multiple renal arteries in a wide, multiethnic population. Secondary objectives are to establish the prevalence of early branching of the renal artery and the prevalence of these variations in left and right kidneys. Methods: this study analyzes the renal arterial anatomy of 20.782 kidneys from 64 anatomical and radiological studies. Results: Multiple renal arteries (MRA) were present in 19,95% of the total kidneys, in number of 2 to 6 arteries arriving to the hilum. The most frequent number of MRA was 2 renal arteries (89,48%), followed by 3 (9,31%), 4 (1,06%), 5 (0,02%) and 6 (0,005%). This last one being found in only one kidney. Reported data on the lateralization of the MRA are rather poor, and among these no side’s predilection was found: MRA were found in 49,83% on the right side and 50,17% of left kidneys. Early branching patterns were described in only one third of the published data, being present in 11,4% of the total kidneys from those data (corresponding in 4,23% of right kidney cases and in 4,52% of left kidney cases; 2,66% had no right/left information). Discussion: the most difficult part was to merge the results from the different studies due to the heterogeneity of their descriptions. A universally accepted medical nomenclature is needed in order to allow a more precise lecture and transmission of results in clinical practice. Renal anatomical variations have clinical and surgical implications in renal transplantation, correctable hydronephrosis, ablation treatment for refractory hypertension or endovascular reconstructions and should be taken into account by every physician.

Efficacy and Safety of Renal Denervation for Patients with Uncontrolled Hypertension in Taiwan: 3-Year Results From the Global SYMPLICITY Registry-Taiwan (GSR-Taiwan).

It is unclear whether renal denervation (RDN) can safely result in blood pressure (BP) reductions in Asian hypertensive patients and whether such reductions would be sustainable. The study is to assess the safety and efficacy of RDN achieved by either main renal artery ablation using the Symplicity FlexTM catheter or main plus branch renal artery ablations using the Symplicity SpyralTM catheter in Taiwanese uncontrolled hypertensive patients enrolled in the Global SYMPLICITY Registry (GSR) with 3 years of follow-up. The GSR is a prospective, open-label, and all-comer registry to evaluate the safety and effectiveness of RDN in patients with uncontrolled hypertension worldwide. Among 26 patients enrolled (mean age, 59.1 ± 13.8 years), 8 were treated with the Symplicity FlexTM catheter, and 18 were treated with the Symplicity SpyralTM catheter. Baseline office systolic BP was 168.2 ± 19.8 mmHg and diastolic BP was 89.0 ± 14.3 mmHg. Office BP reductions following RDN were sustained throughout the follow-up periods of up to 3 years in the Symplicity FlexTM group and 2 years in the Symplicity SpyralTM group. In the Symplicity FlexTM group, the office systolic BP reductions were 14.9 ± 14.7 mmHg and 29.7 ± 25.9 mmHg at 3 months and 3 years, respectively (both p < 0.05 from baseline). In the Symplicity SpyralTM group, the office systolic BP reductions were 21.2 ± 28.7 mmHg and 42.4 ± 10.7 mmHg at 3 months and 2 years, respectively (both p < 0.05 from baseline). There were no significant changes in heart rate or antihypertensive medication classes. Three protocol-defined adverse events occurred in 2 patients, including new-onset end-stage renal disease, stroke, and hospitalization for new-onset heart failure. Given the susceptibility of Asian populations to hypertension, RDN, as a safe antihypertensive procedure with long-lasting BP-lowering effects, could reliably serve as an alternative or complementary BP-lowering strategy for patients with uncontrolled hypertension in Taiwan and other Asian countries.

Complete post-operative resolution of \u201ctemporary\u201d end-stage kidney disease secondary to aortic dissection without static renal artery obstruction: a case study

BackgroundAcute kidney injury (AKI), which may progress to end-stage kidney disease (ESKD), is a potential complication of aortic dissection. Notably, in all reported ESKD cases secondary to aortic dissection, imaging evidence of static obstruction of the renal arteries always shows either renal artery stenosis or extension of the dissection into the renal arteries.Case presentationWe present the case of a 58-year-old man with hypertension who was diagnosed with a Stanford type B aortic dissection and treated with medications alone because there were no obvious findings indicative of dissection involving the renal arteries. He had AKI, which unexpectedly progressed to ESKD, without any radiological evidence of direct involvement of the renal arteries. Thus, we failed to attribute the ESKD to the dissection and hesitated to perform any surgical intervention. Nevertheless, the patient’s hormonal levels, fractional excretion values, ankle brachial indices, and Doppler resistive indices seemed to indirectly suggest kidney malperfusion and implied renal artery hypo-perfusion. However, abdominal computed tomography imaging only revealed progressive thrombotic obstruction of the false lumen and compression of the true lumen in the descending thoracic aorta, despite the absence of anatomical blockage of renal artery perfusion. Later, signs of peripheral malperfusion, such as intermittent claudication, necessitated surgical intervention; a graft replacement of the aorta was performed. Post-operatively, the patient completely recovered after 3 months of haemodialysis, and the markers that had pre-operatively suggested decreased renal bloodstream normalised with recovery of kidney function.ConclusionsTo the best of our knowledge, this is the first report of severe AKI, secondary to aortic dissection, without direct renal artery obstruction, which progressed to “temporary” ESKD and was resolved following surgery. This case suggests that only coarctation above the renal artery branches following an aortic dissection can progress AKI to ESKD, despite the absence of radiological evidence confirming an obvious anatomical blockage. Further, indirect markers suggestive of decreased renal blood flow, such as ankle brachial indices, renal artery resistive indices, urinary excretion fractions, and hormonal changes, are useful for evaluating concomitant AKI and may indicate the need for surgical intervention after a Stanford type B aortic dissection.

1196Transvascular pace-capture of aorticorenal ganglia provides a testable procedural endpoint for transcatheter renal artery denervation and identifies a novel therapeutic ablation target for denervation

Abstract Background Transcatheter renal denervation procedures often produces incomplete renal denervation and inconsistent antihypertensive effect. The lack of an intraprocedural method for renal sympathetic nerve function assessment has precluded a rational and physiologically based approach to ensure adequate denervation has been achieved at the time of the procedure. Purpose To demonstrate that it is possible to localise aorticorenal ganglia via transvascular pacing to provide: 1) a testable procedural endpoint for transcatheter renal denervation and, 2) a novel ablation target for renal denervation. Methods High frequency pacing in the inferior vena cava and aorta, invasive blood pressure measurements and renal angiography was performed in sheep (N=19) to identify ARG pace-capture sites by concurrent hypertensive and renal vasoconstrictive responses. Group A (N=5) underwent ink injection labelling at the ARG pace-capture site for histological verification; Group B (N=6) received unilateral irrigated radiofrequency ablation of ARG pace-capture sites and assessment of renal innervation at 1week post-procedure; and Group C (N=8) had ARG pacing performed prior to and 2–3 weeks after unilateral transcatheter microwave renal denervation. Results ARG pace-capture responses were observed at paired discrete sites in the posterior IVC and anterolateral aorta approximately 40mm above the ipsilateral renal artery. Pacing elicited a mean arterial blood pressure change of 22.2 [IQR 15.5–34.3] mmHg, p&lt;0.001, together with ipsilateral renal vasoconstriction with main renal artery calibre change of −0.42mm [IQR −0.64mm to −0.24mm] measured with quantitative coronary analysis (QCA), p&lt;0.0001, and branch renal artery median pixel density index change −10.4% [IQR −22.7% to −3.0%], p=0.003. Contralateral renal arterial vasoconstriction was not observed consistently at either the main or branch renal artery level. Sympathetic ganglionic tissue was observed at ARG pace-capture sites, and ganglion ablation caused significant ipsilateral renal denervation with a median hilar functional sympathetic nerve area reduction of 51% [IQR 24%–52%], p=0.043, and renal cortical norepinephrine reduction of 54% [IQR 36%–59%], p=0.043. Circumferential renal denervation resulted in immediate and sustained abolition of ARP pacing induced renal vasoconstriction and significant ipsilateral renal denervation. Conclusion Localisation of ARG using transvascular pacing is feasible with pace-capture demonstrated by concurrent hypertensive and ipsilateral renal arterial vasoconstrictive responses. Abolition of ARG pacing induced renal arterial vasoconstriction may indicate successful renal sympathetic denervation, providing a physiological procedural endpoint to guide transcatheter renal denervation. Additionally, ablation of ARG could provide an alternative or adjunctive method for renal denervation. Acknowledgement/Funding University of Sydney; Western Sydney Local health District; National Health and Medical Research Council of Australia; National Heart Foundation (Au)

Clinical characteristics of 57 patients with polyarteritis nodosa and renal involvement

Objective: To investigate the clinical characteristics of polyarteritis nodosa (PAN) patients with renal involvement. Methods: PAN patients admitted to the department of rheumatology, department of pediatrics, department of nephrology, general internal medicine department and department of vascular surgery at Peking Union Medical College Hospital from June 2012 to August 2018 were enrolled in this study and were divided into two groups according to renal involvement or not. The clinical characteristics were analyzed. Results: A total of 94 PAN patients were finally enrolled and 57 (60.64%) presented kidney manifestation. The mean age of onset was (37.76±17.40) years old and the interval from onset to diagnosis was 10 (0 to 240) months. Forty patients were misdiagnosed once or more times. In patients with renal involvement, 9 cases suffered from renal ischemia or infarction, 31 with microscopic haematuria, 26 with proteinuria, renal artery or its branch involved in 17 cases, renal vein thrombosis in 1 case, 4 cases with pyeloureterectasis, one case with renal fascia thickening, 33 cases with impaired renal function (serum creatinine>84 μmol/L) including creatinine>140 μmol/L in 10 patients. Renal artery branch stenosis was the most common presentation [9 cases (52.94%)] of renal vascular involvement, other abnormalities including nodular dilatation [4 cases (23.53%)], occlusion [3 cases (17.65%)]. There were significant differences (P<0.05) in the PAN patients with and without renal involvement in the following: age of onset [(33.72±16.13) years vs. (43.97±17.66) years, t(2)=2.901, P=0.005], weight loss(≥4kg since PAN onset) [25(43.86%) vs. 7(18.92%), χ(2)=6.216, P=0.013], elevation of diastolic blood pressure [22(38.60%) vs. 7(18.92%), χ(2)=4.072, P=0.044], acromegaly gangrene [18(31.58%) vs. 21(56.76%), χ(2)=5.859, P=0.015], and gastrointestinal artery involvement [20(35.09%) vs. 6(1.22%), χ(2)=3.993, P=0.046]. Laboratory parameters and the application of glucocorticoid and cyclophosphamide therapies were similar in two groups (all P>0.05). Conclusion: Young PAN patients are more likely to be associated with renal involvement, especially gastrointestinal arteries.

Delayed Presentation of Renal Arterio-Venous Fistula and Pseudoaneurysm in Native Left Kidney in Allograft Recipient: A Case Report

Iatrogenic complications due to renal biopsy majorly include formation of an arterio-venous fistula, pseudoaneurysm or arterio-ureteral fistula. These complications are observed within a span of few days post biopsy and are rare after few years. We reported a case of 32-year-old renal allograft recipient male presenting 6 years post biopsy of the left kidney with left lumbar region pain who was eventually diagnosed with arterio-venous fistula and pseudoaneurysm involving inferior interlobular branch of left renal artery. Superselective embolization was achieved using coils and high concentration glue and transient placement of a venous occlusion balloon with complete technical and clinical success. Keywords: renal arterio-venous fistula; renal biopsy; renal pseudoaneurysm.

RELEVANCE OF TARGETING THE DISTAL RENAL ARTERY AND BRANCHES WITH RADIOFREQUENCY RENAL DENERVATION–INSIGHTS FROM A POST-HOC ANALYSIS IN HYPERTENSIVE CHRONIC KIDNEY DISEASE PATIENTS

Objective: We previously reported that renal denervation (RDN) approach aimed at chronic kidney (CKD) disease and hypertension management was efficient in reducing blood pressure (BP) in resistant hypertensive patients with chronic kidney disease (CKD) in the long-term. Taking into account recent data obtained from the SPYRAL HTN-OFF and HTN-ON MED trials, we now performed a post hoc analysis in our resistant hypertensive patients with CKD to evaluate whether our (RDN) approach yielded a close association with the magnitude of the BP response. Design and method: We performed a post hoc analysis of a 24-month follow up evaluation of 30 patients who underwent RDN between 2011 and 2012 using a standard irrigated cardiac ablation catheter radiofrequency based approach. We assessed the association between changes from baseline to 12 and 24-months follow-up in mean ambulatory systolic and diastolic BP and the total number of ablation sites. Furthermore, we explored whether or not distal vs proximal treatment may influence this association. Results: The mean change in ambulatory systolic BP compared to baseline was −19.4 ± 12.7 mmHg (95%CI: −24.1 to −14.6) at 12-month (p < 0.0001) and −21.3 ± 14.1 mmHg (95%CI: −26.9 to −15.7) at 24-month follow-up (p < 0.0001). There was no correlation between ambulatory systolic BP-lowering effect and the total number (17.7 ± 6.0) of renal artery ablation sites neither at 12 (Pearson: r = −0.3 (95%CI: −0.6 to 0.1), p = 0.1542) nor at 24 (Pearson: r = −0.2 (95%CI: −0.5 to 0.2), p = 0.4009) months post-procedure. However, correlations between ambulatory systolic BP-lowering effect and the number of treatments performed in the distal segment and branches were significant at the 12 (Pearson: r = −0.7 (95% CI: −0.8 to −0.4), p < 0.0001) and 24-months follow-up (Pearson: r = −0.8 (95%CI: −0.9 to −0.6), p < 0.0001). Conclusions: Our findings confirm that in a cohort of CKD patients with resistant hypertension RDN resulted in a significant and sustained ambulatory BP reduction. Importantly, only the number of ablations performed in the distal segment and branches of renal arteries correlated strongly with the long-term systolic BP-lowering efficacy. Our post-hoc analysis supports the notion that RDN performed distally and in the branches may yield a more favourable long-term BP response.

Endovascular treatment of visceral artery and renal aneurysms (VRAA) using a constant mesh density flow diverting stent

BackgroundFlow diverting stents have been used safely and effectively for the treatment of intracranial aneurysms, particularly for large and wide necked aneurysms that are not amenable to conventional endovascular treatment with coiling. The Surpass Streamline device (Stryker Neurovascular, MI, USA) is a relatively new and unique flow diverting stent which maintains constant device mesh density over varying vessel diameters. This may potentially provide advantages compared to other flow diverting stents in achieving aneurysmal occlusion.Case presentationTwo patients with VRAA were treated using the Surpass Streamline device. The first patient was a 65-year-old male with an incidental 2.4 cm aneurysm originating from the hepatic artery near the gastroduodenal artery (GDA). The second patient was a 56-year-old male with an incidental 1.9 cm renal aneurysm arising from an anterior inferior segmental branch of the left renal artery. A Surpass flow diverting stent was used to successfully exclude the aneurysm neck in both cases.Reduced flow was achieved in one patient (equivalent to O’Kelly-Marotta [OKM] Grade B1). Preserved flow and stagnation (equivalent to OKM Grade A3) was achieved in the other. There was preserved distal flow in the parent arteries. No immediate complications were encountered in either case. Complete occlusion of both aneurysms was seen on follow up CT angiographic imaging within 8-weeks.ConclusionsThe Surpass flow diverting stent can be used safely and effectively to treat VRAA. It should be considered in unruptured large and giant wide necked VRAAs aneurysms. Additional large prospective studies are required for further validation.

Relevance of Targeting the Distal Renal Artery and Branches with Radiofrequency Renal Denervation Approaches-A Secondary Analysis from a Hypertensive CKD Patient Cohort.

We searched for an association between changes in blood pressure (BP) at 12 and 24 months after renal denervation (RDN) and the different patterns of ablation spots placement along the renal artery vasculature. We performed a post-hoc analysis of a 24-month follow-up evaluation of 30 patients who underwent RDN between 2011 and 2012 using our previous database. Patients who had (i) resistant hypertension, as meticulously described previously, and (ii) Chronic kidney disease (CKD) stages 2, 3 and 4. Correlations were assessed using the Pearson or Spearman correlation tests as appropriate. The mean change in systolic ambulatory BP monitoring (ABPM) compared to baseline was −19.4 ± 12.7 mmHg at the 12th (p < 0.0001) and −21.3 ± 14.1 mmHg at the 24th month (p < 0.0001). There was no correlation between the ABPM Systolic Blood Pressure (SBP)-lowering effect and the total number of ablated spots in renal arteries (17.7 ± 6.0) either at 12 (r = −0.3, p = 0.1542) or at 24 months (r = −0.2, p = 0.4009). However, correlations between systolic BP-lowering effect and the number of ablation spots performed in the distal segment and branches were significant at the 12 (r = −0.7, p < 0.0001) and 24 months (r = −0.8, p < 0.0001) follow-up. Our findings indicate a substantial correlation between the numbers of ablated sites in the distal segment and branches of renal arteries and the systolic BP-lowering effect in the long-term.

Intrarenal arteriovenous malformation following flexible ureterorenoscopy and holmium laser stone fragmentation: report of a case

BackgroundFlexible ureterorenoscopy (FURS) and holmium laser lithotripsy is currently considered as one of the treatment options for large renal calculi. It has been shown to be safer than percutaneous nephrolithotomy. The latter can sometimes be complicated by the formation of intrarenal arteriovenous malformation (AVM). AVM is extremely rare following FURS and laser lithotripsy. Indeed only one case has been reported on reviewing the literature up to June 2018. We report on the second case illustrating the possibility of developing this major complication following this procedure.Case presentationA 79 years old diabetic and hypertensive male with stage-4 chronic kidney disease who previously had left extracorporeal shockwave lithotripsy and FURS with Holmium laser lithotripsy, presented with bilateral large renal calculi. He underwent simultaneous bilateral FURS and Holmium laser lithotripsy and was discharged home the following day with almost clear urine. Four days post-discharge, he presented with gross hematuria for which he required hospitalization and blood transfusion. CT scan demonstrated left subcapsular, perinephric and retroperitoneal hematoma. Angiography showed contrast extravasation from pseudoaneurysms in two small branches of left renal artery. Both were selectively embolized with micro-coils and this led to the cessation of the hematuria.ConclusionsDespite the relative safety of FURS and Holmium laser lithotripsy, it can be associated with major complications like intrarenal AVM. This can probably be prevented by careful and judicious use of laser energy in patients with large stone burden and premorbid conditions.

Renal Artery Branch Denervation: Evaluation of Lesion Characteristics Using a Thermochromic Liquid Crystal Phantom Model

Lately, combined main vessel and branch ablation has been recommended during radiofrequency (RF) renal artery denervation. Utilising a validated renal artery phantom model, we aimed (1) to determine thermal injury extent (lesion depth, width and circumferential coverage) and electrode-tissue interface temperature for branch renal artery ablation, and (2) to compare the extent of thermal injury for branch versus main vessel ablation using the same RF System. We employed a gel based renal artery phantom model simulating variable vessel diameter and flow, which incorporated a temperature sensitive thermochromic-liquid-crystal (TLC) film for assessing RF ablation thermodynamics. Ablations in a branch renal artery model (n = 32) were performed using Symplicity Spyral (Medtronic, Minneapolis, MN, USA). Lesion dimensions defined by the 51 °C isotherm, circumferential injury coverage, and electrode-tissue interface temperature were measured for all ablations at 60 seconds. Lesion dimensions were 2.13 ± 0.13 mm and 4.13 ± 0.18 mm for depth and width, respectively, involving 23% of the vessel circumference. Maximum electrode-tissue interface temperature was 68.31 ± 2.29 °C. No significant difference in lesion depth between branch and main vessel ablations was found (Δ = 0.02 mm, p = 0.60). However, lesions were wider in the branch (Δ=0.49 mm, p < 0.001) with a larger circumferential coverage compared to main vessel (arc angle of 82.02±3.27° versus 54.90±4.36°, respectively). In the phantom model, branch ablations were of similar depth but had larger width and circumferential coverage compared to main vessel ablations. Concerning safety, no overheating at the electrode-tissue interface was observed.

The applied anatomy of vascular variability of duplex kidney in children

Objective To study the vascular anatomy of duplex kidney and to provide a scientific basis for surgical resection of the renal segment. Methods From February 2012 to April 2018, the clinical data of 84 children with renal duplex kidney disease admitted to our hospital, were reviewed and analyzed. Among them, 75 cases (89.3%) were unilateral and 9 cases (10.7%) were bilateral. According to the preoperative CT+ CTA and the duplicated renal morphology, size, location, and anatomical relationship of the kidney segment, combined with the branches and passage of the renal artery which supplies the upper moiety, it described the blood supply of the upper renal moiety. At the same time, it analyzed various types of embryological related factors and gender differences and summarized the tips for laparoscopic surgery. Results Of the 93 duplex kidneys, 69 (74.2%) were supplied with 1 artery, and 25 (26.9%) were supplied with 2 or more arteries. Based on the shape and orifice of artery, they were divided into 3 types. The most common type was that the renal artery separated into two or more arteries near the renal parenchyma. The upper and lower renal poles were respectively supplied, which could be summarized as early branching, a total of 71 sides (76.3 %). The second type was the arteries from abdominal aorta or its branches, directly flowing into the upper renal pole, which was classified into the sub-renal artery, a total of 18 sides (19.4%). The others (4 sides, 3.3%) were less common, and most of them were a combination of the above-mentioned two types, and one of them whose upper pole was supplied by branches of adrenal artery. Based on the classification of vascular variability, no significant difference was found between males and fenmals, or left and right sides. Conclusions The upper renal moiety are mainly supplied by one branch of renal artery, and the most common type of this artery is prehilar branch, without gender difference. The determination of vascular variability before surgery can avoid bleeding during surgery and avoid accidental injury of normal blood vessels. Key words: Duplex kidney; Vascular anatomy; Laparoscopic surgery