Renal Pseudoaneurysms and Arteriovenous Fistulas as a Complication of Nephron-Sparing Partial Nephrectomy: Technical and Functional Outcomes of Patients Treated With Selective Microcoil Embolization During a Ten-Year Period

Renal pseudoaneurysm after calculous pyelonephritis

Introduction

Renal pseudoaneurysms reportedly occur after partial nephrectomy, renal trauma, or percutaneous procedures. Renal pseudoaneurysms can also occur after renal inflammation; however, such cases are rare and seldom reported.

Case presentation

A 53-year-old man presented to our emergency room with a 3-day history of fever and right back pain. A blood sample revealed severe inflammation and computed tomography showed an 8 mm diameter stone in the right middle ureter and hydronephrosis. The patient was diagnosed with calculous pyelonephritis and underwent emergency ureteral stenting and antibiotic therapy. On day 8 of hospitalization, hematuria and right back pain developed, and on day 9 bladder tamponade and anemia developed. Contrast-enhanced computed tomography revealed a ruptured pseudoaneurysm, and the patient underwent successful angioembolization. The patient was discharged on day 23.

Conclusion

We report a case of a renal pseudoaneurysm possibly caused by calculous pyelonephritis.

Selective Arterial Embolization of Pseudoaneurysms and Arteriovenous Fistulas after Partial Nephrectomy: Safety, Efficacy, and Mid-Term Outcomes

The primary objective was to evaluate the clinical success rate after endovascular embolization of iatrogenic vascular lesions caused during partial nephrectomy. The secondary objective was to evaluate the technical success and to assess potential effects on renal function. We retrospectively included consecutive patients from our center who underwent selective embolization to treat iatrogenic renal arterial lesions induced during partial nephrectomy between June 2010 and June 2020. The technical and clinical success rates and renal outcomes were collected. We identified 25 patients with 47 pseudoaneurysms and nine arteriovenous fistulas. Among them, eight were treated by coils only, eight by liquid embolization agents only, and nine by both. The technical success rate was 96% after the first attempt and 100% after the second attempt. The median follow-up was 27.1 ± 24.3 months. Clinical success, defined as no need for further hemostatic surgery during follow-up, was also obtained in 96% and 100% of patients with one and two attempts, respectively. Renal function estimated by the modification of diet in renal disease equation did not change significantly despite a mean 13.8% ± 15.1% decrease in kidney functional volume estimated by angiography. No complications were attributable to the endovascular treatment. No significant difference was found across embolization agents; however, the subgroup sizes were small. Endovascular embolization is safe and effective for treating iatrogenic arterial lesions after partial nephrectomy: success rates are high, complications are infrequent, and renal function is maintained. Recommendations by interventional radiology societies are needed to standardize this treatment.

Computed Tomography-Guided Percutaneous Lung Biopsy Complicated by Symptomatic Systemic Air Embolism: Case Report and Review of the Literature

Surgical procedures in highly vascularized renal parenchyma sometimes can cause iatrogenic vascular complications. Although incidence renal pseudoaneurysms after partial nephrectomy is low, around 1%, clinical presentation of these patients can be quite severe – hematuria, lumbar pain, dizziness, weakness. Prompt and precise diagnostics and treatment are essential. Ultrasound and Computed Tomography are two most common diagnostic approaches for the assessment of pseudoaneurysms or arteriovenous fistulas following partial nephrectomy. Endovascular selective microcoil embolization is a safe and effective kidney-preserving procedure for treating iatrogenic vascular complications. Although when embolizing renal arteries some of renal parenchyma loses perfusion and becomes fibrotic, no significant decrease in renal function in early post-embolization period was noted. Comparing open surgery to endovascular treatment of pseudoaneurysms, latter one allows shorter average hospital stay and less frequent cardiac and peripheral vascular complications. The article discusses a case of a patient that had developed renal pseudoaneurysm after partial nephrectomy. During a routine check-up of a middle-aged woman a presumable renal cyst was found. On more throughout examination the cyst was ruled as a tumour and partial nephrectomy was performed. After 12 days from surgery patient was admitted to hospital complaining macrohematuria, lower abdomen pain, episodic right-side ache. Urgent contrast enhanced computed tomography was performed, which confirmed that patient was bleeding from the operated kidney. Patient was admitted to interventional radiology departament and perform embolization of bleeding vessel. After embolization of pseudoaneurysm, bleeding was controlled and patient was completely treated.

Imaging and surgical predictive factors for postoperative hemorrhage after partial nephrectomy and clinical results of trans-arterial embolization

Partial nephrectomy (PN) has been established as the standard treatment for T1 renal tumors, and postoperative hemorrhage due to vascular complications is a rare but potentially life-threatening complication reported after PN. Thus, this study evaluated the imaging and surgical factors associated with postoperative hemorrhage after PN and the clinical results of trans-arterial embolization. A retrospective review of the institutional PN database was performed from May 2012 to January 2019, revealing that we performed 810 PN procedures at our institution. In total, 12 patients were referred to the interventional radiology department for vascular complications after the procedure. Patients with and without transarterial embolization (TAE) were age- and sex-matched with 56 patients. Preoperative imaging characteristics and operative details were considered. Univariable and multivariable analyses were used to test their eventual association with the occurrence of hemorrhage. Furthermore, renal functions at diagnosis, after operation or embolization for TAE cases, and at the last follow-up were recorded. A diagnosis of hemorrhage was made at a median of 4 (range, 0-25) days after surgery. The majority of patients (50%) presented with gross hematuria. T test revealed higher renal tumor-parenchyma contact area (TPA) (P = .0407), Length-A (P = .0136), Length-P (P = .0267), operation time (P = .0214) and estimated blood loss (P = .0043) in patients with hemorrhage than in controls. Binary logistic regression analysis identified TPA (P = .048) and estimated blood loss (P = .042) as independent predictors for postoperative hemorrhage with an area under the ROC curve of 0.705 (64% sensitivity and 79% specificity). In conclusion, the occurrence of hemorrhage after PN was associated with a larger TPA and more estimated blood loss during the procedure. In patients who underwent selective TAE, renal function remained comparable with that of controls.

Safety and efficacy of embolotherapy for severe hemorrhage after partial nephrectomy

BACKGROUND

Partial nephrectomy may be complicated by postoperative hemorrhage, which may be treated by transcatheter embolization.

PURPOSE

To assess the safety and efficacy of embolotherapy for hemorrhagic complications of partial nephrectomy and to analyze the potential correlation between multiple bleeding sites on angiography and surgical complexity.

MATERIAL AND METHODS

A cohort of 25 patients presenting with severe, postoperative bleeding after partial nephrectomy and treated with catheter-directed superselective embolization was included. Patients' demographics, radiological investigations before the embolization, and clinical outcome after embolization were analyzed. Mann-Whitney U test was used to analyze the potential difference in the RENAL score between patients with one or more bleeding sites in the resection area.

RESULTS

Selective renal angiography revealed multiple bleeding sites at the resection bed in 8 (32%) patients with amorphous contrast extravasation in 10 (40%) patients. Embolization with use of a microcatheter and microcoils was effective to stop the bleeding in all but one patient, the latter requiring a second embolization two days later. Transient decrease in renal function was noted in 3/25 (12%) patients with full recovery in two of the three. Patients with multiple bleeding sites did not show significantly different RENAL scores compared to patients with a single bleeding site (P = 0.148).

CONCLUSION

Embolotherapy for postoperative partial nephrectomy-related bleeding is safe and effective with a low rate of recurrent bleeding. The number of bleeding sites at the resection area did not correlate to the RENAL score.

Clinical factors that influence the occurrence of symptomatic pseudoaneurysms and arteriovenous fistulas after partial nephrectomy: multi-institutional study of renal function outcomes after one year of selective arterial embolization

PURPOSE

Renal artery pseudoaneurysms (RAPs) and arteriovenous fistulas (AVFs) are rare but potentially life-threatening complications after partial nephrectomy (PN). Selective arterial embolization (SAE) is an effective method for controlling RAPs/AVFs. We assessed the clinical factors affecting the occurrence of RAPs/AVFs after PN and the effects of SAE on postsurgical renal function.

MATERIALS AND METHODS

Four hundred ninety-three patients who underwent PN were retrospectively reviewed. They were placed in either the SAE or the non-SAE group. The effects of clinical factors, including R.E.N.A.L. scores, on the occurrence of RAPs/AVFs were analyzed. The influence of SAE on the estimated glomerular filtration rate (eGFR) during the first postoperative year was evaluated.

RESULTS

Thirty-three (6.7%) patients experienced RAPs/AVFs within 8 days of the median interval between PN and SAE. The SAE group had significantly higher R.E.N.A.L. scores, higher N component scores, and higher L component scores (all, p <0.05). In the multivariate analysis, higher N component scores were associated with the occurrence of RAPs/AVFs (Odds ratio: 1.96, p=0.039). In the SAE group, the mean 3-day postembolization eGFR was significantly lower than the mean 3-day postoperative eGFR (p <0.01). This difference in the eGFRs was still present 1 year later.

CONCLUSIONS

Renal tumors located near the renal sinus and collecting system were associated with a higher risk for RAPs/AVFs after PN. Although SAE was an effective method for controlling symptomatic RAPs/AVFs after PN, a procedure-related impairment of renal function after SAE could occur and still be present at the end of the first postoperative year.

Selective Trans-arterial Embolization of Iatrogenic Vascular Lesions Did Not Influence the Global Renal Function After Partial Nephrectomy

OBJECTIVE

To evaluate the renal function outcomes after selective trans-arterial embolization (SAE) of iatrogenic vascular lesions (IVL), including pseudoaneurysm and arteriovenous fistula, following partial nephrectomy (PN).

MATERIALS AND METHODS

A multi-institutional study was conducted including consecutive patients who underwent PN between January 2009 and March 2019. Two surgical approaches were used: open and robot-assisted PN. Patients with SAE were identified and matched (1:2) with patients without IVL. The matching criteria were age, gender, Charlson score, creatinine clearance, RENAL score, and tumor size. The primary outcome was the evolution of global renal function at 6-months postoperatively.

RESULTS

A total of 493 consecutive PN (360 open PN and 133 robot-assisted PN) were included. IVL occurred in 17 cases (3.4%) without statistical difference according to the surgical approach (P = .78). Patients from embolization group were matched to 34 cases without postoperative IVL. Groups were comparable concerning clinical, tumor and surgical characteristics. The clinical success of SAE, defined as the absence of recourse to a second embolization or a total nephrectomy, was obtained in 16 (94.1%) cases. No minor or major complications were reported after SAE. The preoperative estimated glomerular filtration rate (eGFR) was similar between control group (93 [85-102] ml/min) and embolization group (95 [83-102] ml/min) (P = .99). Median (IQR) eGFR between control group (87 [72-95] ml/min) and embolization group (83 [76-93] ml/min) at a follow-up of 6 months showed no significant difference (P = .73).

CONCLUSION

IVL are rare complications of PN. SAE is an effective and minimally invasive management tool, with no deleterious effect on global renal function.

Performing an early systematic Doppler-ultrasound fails to prevent hemorrhagic complications after complex partial nephrectomy

Background:

The aim of this work was to assess the clinical relevance of a systematic postoperative Doppler-ultrasound (DU) after complex partial nephrectomy (PN).

Materials and methods:

All patients who underwent open, laparoscopic or robotic PN from 2014 to 2017 at our institution were included. Postoperative hemorrhagic complications (HCs) were defined as the occurrence of blood transfusion, hemorrhagic shock, arterial embolization, or re-hospitalization for hematoma. DU was systematically performed between post-op day 4 and 7 for every complex tumor (RENAL score ⩾ 7). DU was considered positive in the presence of pseudoaneurysm (PA) or arteriovenous fistula (AVF).

Results:

Among 194 patients, 117 underwent DU (60.3%). We reported 22 HCs (11.3%) requiring 8 selective embolization procedures (4.1%). HCs occurred during the hospital stay in 17 patients (77.3%), thus directly diagnosed on a computed tomography scan. Among the five patients (22.7%) with HC occurring after hospital discharge, between day 7 to 15, four had a previously negative systematic DU. Overall, systematic DU was positive in only five patients (4.3%) with only one patient of 194 (0.5%) undergoing preventive embolization of a PA-AVF. The negative predictive values (NPVs) and positive predictive values of DU were respectively 96.5% and 5%, with 20% sensitivity and 96.5% specificity.

Conclusions:

Our results may suggest offering systematic DU in patients under antiplatelet therapies, with high tumor size (>T1b), or early postoperative hemoglobin variations. A high NPV of DU might be counterbalanced by its low sensibility. Since all secondary HCs occurred between postoperative day 7 to 15, our results may suggest differing DU in selected cases.

Influence of symptomatic pseudoaneurysms on postoperative renal function after partial nephrectomy: results of a matched pair analysis

PURPOSE

A symptomatic pseudoaneurysm (SPA) is a rare but severe complication after partial nephrectomy (PN). Selective trans-arterial embolization (TAE) is the treatment of choice with high success rates. However, the influence of this intervention on postsurgical renal function has not been studied.

METHODS

Between 2005 and 2016 we performed 1047 PNs at our institution. Postsurgical SPA occurred in 40 patients (3.8%). Patients with and without SPA were matched in a 1:2 ratio concerning tumor complexity (RENAL) and pre-operative renal function (CKD stage). Any CKD upstage and a relevant CKD progression (CKD ≥ III) were defined as endpoints. Furthermore, the influence of the amount of contrast agent applied during TAE was assessed.

RESULTS

All patients with SPA were treated successfully with TAE. No significant difference could be detected concerning clinical, functional and surgical aspects. Median follow-up time accounted for 12.5 (6.75-27.5) months. Kaplan-Meier analyses detected an increased rate of any CKD upstage (p = 0.066) and relevant CKD progression (p = 0.01) in patients with SPA. Multivariate analysis identified post-operative SPA to be an independent predictor for a relevant CKD progression (HR 4.15, p = 0.01). The amount of contrast agents used did not have an impact on the development of a relevant CKD progression (p = 0.72).

CONCLUSION

Patients treated with TAE after PN show an additional risk for an impairment of renal function over time. Hence, those patients should explicitly be informed about possible consequences and closely monitored by nephrologists.

Use of angioembolization in urology: a review

This review discusses current and developing indications for angioembolization (AE) techniques in urology cases, including trauma and non-trauma uses for kidney, prostate, and bladder conditions. AE methods, complications and technical and clinical outcomes are outlined for each indication for the purpose of aiding urologists in selecting ideal candidates for this procedure.

Preoperative Nomograms for Predicting Renal Function at 1 Year After Partial Nephrectomy

INTRODUCTION

Partial nephrectomy (PN) reduces the risk of postoperative chronic renal insufficiency (CRI). However, some patients still develop CRI after PN, and may eventually require dialysis. Being able to predict renal function before PN helps in counseling patients and managing expectations. We aimed to construct nomograms that predict estimated glomerular filtration rates (eGFRs), defined by the modification of diet in renal disease (MDRD) and the chronic kidney disease epidemiology collaboration (CKD-EPI) formulae, at 1 year after PN, using only preoperative covariates as predictors.

PATIENTS AND METHODS

We identified patients who underwent PN in our institution between 2004 and 2016, with known postoperative serum creatinine levels at 1 year. The preoperative covariates included patients' demographics, chronic comorbid conditions, tumor characteristics, and preoperative renal status. The endpoints were eGFRs at 1 year after PN, calculated using the MDRD and the CKD-EPI formulae. We first identified preoperative covariates with significant associations with the endpoints by Pearson correlation and independent samples t-test. Suitable covariates were then included in two multivariate linear regression models, for constructing and internally validating two nomograms.

RESULTS

461 patients were eligible for analysis. The percentage of patients with eGFR below 60 mL/min/1.73 m² increased from 25% before PN to 35% at 1 year after PN. We included age, gender, African American race, body mass index, preoperative creatinine level, ipsilateral renal volume, solitary kidney status, tumor diameter, hypertension, diabetes, ischemic heart disease, and previous stroke in the multivariate linear regression models for nomogram construction. Internal validation showed bootstrap-corrected coefficients of determination of 0.61 and 0.70, for predicting eGFRs defined by the MDRD and CKD-EPI formulae, respectively.

CONCLUSIONS

We constructed and internally validated two nomograms to predict eGFRs at 1 year after PN, using only preoperative covariates as predictors.

Management of iatrogenic renal arteriovenous fistula and renal arterial pseudoaneurysm by transarterial embolization: A single center analysis and outcomes

The purpose of this study was to evaluate the efficacy and safety of transarterial embolization (TAE) for iatrogenic renal arterial pseudoaneurysm and arteriovenous fistula at our center.Our retrospective analysis included 27 patients who received TAE for iatrogenic renal arterial pseudoaneurysm and arteriovenous fistula between January 2006 and January 2016. Data on demographics, type of minimally invasive renal procedures, clinical manifestation, imaging features, embolization procedure, and perioperative details were collected. The technical and clinical success rates were analyzed. Furthermore, the changes in serum creatinine and eGFR before and after embolization were recorded and compared by t test.The median time between iatrogenic renal injury and TAE was 3 days (range, 0-110 days), with most patients (24/27, 88.9%) receiving TAE within 14 days. Only 1 patient was diagnosed with renal artery pseudoaneurysm 110 days after laproscopic partial nephrectomy. The technical and clinical success rates were 100% and 96.3%, respectively, with 1 patient requiring a second embolotherapy at the third postoperative day. No other patient required additional endovascular or surgical intervention due to recurrent hemorrhage. The mean serum creatinine before TAE was 92.8 ± 25.3 μmol/L and after TAE, 96.1 ± 27.7 μmol/L (P = .095). The eGFR of pre- and postembolization was 75.2 ± 26.5 mL/min/1.73 m and 72.5 ± 26.2 mL/min/1.73 m (P = .16). No severe complications were observed during follow-up.This retrospective review demonstrated that TAE for the treatment of iatrogenic renal artery pseudoaneurysm and/or arteriovenous fistula was safe and associated with high technical and clinical success rate.

Hidden Renal Artery Pseudoaneurysm: The Need for Repeat Angiographic Intervention in a Symptomatic Patient

Renal artery pseudoaneurysm (RAP) is a well-known and life-threatening complication of partial nephrectomies. Angioembolization is the preferred intervention, allowing for visualization, diagnosis, and treatment in 96% of cases. We report a case of a pseudoaneurysm that was difficult to diagnose even with optimal technique, requiring repeat imaging and additional angiographic intervention. Our case shows that RAP after partial nephrectomies may be difficult to diagnose even with high suspicion and appropriate technique. Repeat angiography may be required. Urologists and interventional radiologists together must keep RAP high on the differential even after a negative angiogram to adequately diagnose and treat symptomatic patients.

Managing Complications Following Nephron-Sparing Procedures for Renal Masses

Small renal malignancies are commonly treated with nephron-sparing procedures including partial nephrectomy and percutaneous ablation. Although these procedures offer faster patient recovery and preserve renal function, a variety of complications can occur. Here, we review vascular and nonvascular complications associated with nephron-sparing renal mass treatments and discuss options for minimally invasive image-guided management.