Arteriovenous fistulas thrombosis in hemodialysis patients with COVID-19.

BACKGROUND: The current Coronavirus disease 2019 (COVID-19) outbreak is associated with significant mortality, especially in patients suffering from end stage renal disease (ESRD) and hemodialysis patients. Several previous studies reported an over-risk of arterial and venous thrombosis, in particular pulmonary embolism and venous thrombosis of catheter in COVID19 patients in intensive care unit. However, arteriovenous fistula (AVF) thrombosis has rarely been reported yet in these patients. AVF thrombosis is a serious complication that impacts significantly patients outcome. Here, we aim to describe characteristics and prognosis of a cohort of COVID-19 hemodialysis (HD) patients presenting with AVF thrombosis. METHODS: In the Ile de France region (Paris area) during the March 11th-April 30th 2020 period, fistula thrombosis cases were collected among COVID-19 hemodialysis patients in seven dialysis units and in interventional vascular departments. These patients' characteristics were analyzed through a review of the patient's medical records. RESULTS: Seventeen patients were included in our study (median age 69 years). Ten patients (59%) were men. Ten patients (59%) were diabetic and 88% had a high blood pressure. The mortality rate in these patients was 47%. All thrombosis treated with a declotting procedures (64%) were successfully cleared, but with early relapse in 36%. CONCLUSION: Our study highlights AVF thrombosis as a severe complication in COVID-19 hemodialysis patients that contributed to the severity and accelerated death.

Reducing the risk of bleeding after myomectomy: is preemptive embolization a valuable tool?

PURPOSE: Abdominal myomectomy can be a challenging procedure, with elevated intraoperative blood loss and post-operative complications such as the need for blood transfusion and hemostasis with sometimes hysterectomy. Previous studies suggested that preemptive uterine artery embolization (PUAE) might reduce intraoperative blood loss. MATERIALS AND METHODS: We reviewed all cases of abdominal myomectomy in our institution between January 2016 and June 2018. Out of 119 cases, 16 patients had PUAE and 103 did not. The objective of our study was to determine whereas PUAE reduced blood loss and post-operative complication rate. RESULTS: In our study, there was no difference between the two groups in regard to average blood loss (128 vs 192 mL, OR 1,00 [0.99;1,01], p = 0,73), difference between pre- and post-operative hemoglobin level (- 1,15 g/dL vs - 1,32 g/dL, OR 0,91 [0.47;1,73], p = 0,79), and post-operative complications (need for transfusion, surgical revision, post-operative embolization, hysterectomy). CONCLUSION: Our findings could not conclude that PUAE is effective in reducing intraoperative blood loss during abdominal myomectomy, but it should still be considered an option for patients with large or multiple myomas, with a specific situation or previously operated, who wish to preserve their uterus.

Three-dimensional Image Fusion Guidance for Transjugular Intrahepatic Portosystemic Shunt Placement.

INTRODUCTION: To assess the safety, feasibility and effectiveness of image fusion guidance with pre-procedural portal phase computed tomography with intraprocedural fluoroscopy for transjugular intrahepatic portosystemic shunt (TIPS) placement. MATERIALS AND METHODS: All consecutive cirrhotic patients presenting at our interventional unit for TIPS creation from January 2015 to January 2016 were prospectively enrolled. Procedures were performed under general anesthesia in an interventional suite equipped with flat panel detector, cone-beam computed tomography (CBCT) and image fusion technique. All TIPSs were placed under image fusion guidance. After hepatic vein catheterization, an unenhanced CBCT acquisition was performed and co-registered with the pre-procedural portal phase CT images. A virtual path between hepatic vein and portal branch was made using the virtual needle path trajectory software. Subsequently, the 3D virtual path was overlaid on 2D fluoroscopy for guidance during portal branch cannulation. Safety, feasibility, effectiveness and per-procedural data were evaluated. RESULTS: Sixteen patients (12 males; median age 56 years) were included. Procedures were technically feasible in 15 of the 16 patients (94%). One procedure was aborted due to hepatic vein catheterization failure related to severe liver distortion. No periprocedural complications occurred within 48 h of the procedure. The median dose-area product was 91 Gy cm2, fluoroscopy time 15 min, procedure time 40 min and contrast media consumption 65 mL. Clinical benefit of the TIPS placement was observed in nine patients (56%). CONCLUSION: This study suggests that 3D image fusion guidance for TIPS is feasible, safe and effective. By identifying virtual needle path, CBCT enables real-time multiplanar guidance and may facilitate TIPS placement.

Radiocephalic fistula complicated by distal ischemia: treatment by ulnar artery dilatation.

Hand ischemic steal syndrome due to a forearm arteriovenous fistula is a rare occurrence. However, its frequency is increasing with the rise in numbers of elderly and diabetic patients. This complication, which is more common for proximal than for distal accesses, can be very severe and may cause loss of hand function, damage to fingers, and even amputation of fingers or the hand. Its treatment is difficult and often leads to access loss. We report here a case of severe hand ischemia related to a radiocephalic fistula successfully treated by ulnar artery dilatation.

Low-flow maturation failure of distal accesses: Treatment by angioplasty of forearm arteries.

BACKGROUND: Forearm artery lesions are a frequent cause of distal fistula maturation failure. Surgical treatment is difficult because of highly calcified arteries. To redo the arteriovenous anastomosis higher up the forearm is technically difficult and often ineffective because arteries cannot be enlarged. It also causes a loss in puncture zone. Creation of brachial accesses leads to a high risk of distal ischemia. METHODS: From September 2000 to September 2006, we performed percutaneous transluminal angioplasty (PTA) of forearm arteries in 25 patients with failing distal access maturation. We reported immediate results of the dilatation and retrospectively analyzed the outcome of the accesses after the procedure. RESULTS: Forearm artery PTA was achieved in all 25 patients. Three main complications occurred: severe spasms precluding precise assessment of the artery patency after dilatation, rupture easily treated by prolonged low-pressure balloon inflation, and early rethrombosis leading to access loss. Follow-up was available in 23 patients. PTA failed to restore a sufficient access flow in two patients (the access loss and an insufficient increase in flow). In the remaining 21 (91%), accesses started to be used for hemodialysis without difficulties. Primary patency access rates after PTA were 83% (range, 60%-93%) at 1 year and 74% (range, 47%-89%) at 2 years. Secondary access patency rates were 86% (range, 64%-95%) at 1 and 3 years. CONCLUSION: When a distal access fails to mature because of forearm artery lesions, PTA should be done and will salvage the fistula without risk of distal ischemia and cardiac failure. Efficacy of PTA clearly influences surgical strategy and is a major argument in favor of attempting to create distal accesses in patients with mild distal artery lesions. Even in cases of failure, such as early occlusion of the fistula, this technique does not jeopardize further proximal access creation. Forearm access creation should be avoided only in cases of extremely severe distal artery lesions.

Embolization of the internal iliac artery: cost-effectiveness of two different techniques.

The purpose of this study was to compare the cost-effectiveness of coils versus the Amplatzer Vascular Plug (AVP) for occlusion of the internal iliac artery (IAA). Between 2002 and January 2006, 13 patients (mean age 73 +/- 13 years) were referred for stent-grafting of abdominal aortic aneurysm (n = 6); type I distal endoleak (n = 3), isolated iliac aneurysm (n = 3), or rupture of a common iliac aneurysm (n = 1). In all patients, extension of the stent-graft was needed because the distal neck was absent. Two different techniques were used to occlude the IIA: AVP in seven patients (group A) and coil embolization in six patients (group C). Immediate results and direct material costs were assessed retrospectively. Immediate success was achieved in all patients, and simultaneous stent-grafting was successfully performed in two of six patients in group C versus five of seven patients in group A. In all group A patients, a single AVP was sufficient to achieve occlusion of the IIA, accounting for a mean cost of 485 euros, whereas in group C patients, an average of 7 +/- 3 coils were used, accounting for a mean cost of 1,745 euros. Mean average cost savings using the AVP was 1,239 euros. When IIA occlusion is needed, the AVP allows a single-step procedure at significant cost savings.

Percutaneous manual aspiration embolectomy of renal vein thrombosis due to acute pyelonephritis.

We report the case of a 50-year-old man who presented to our institution with septic thrombosis of the renal vein which had not resolved despite several days of antibiotic therapy. Optimal restoration of renal vein flow was obtained by percutaneous manual aspiration embolectomy (PMAE) in this patient with contraindication to fibrinolytic therapy and surgery.

[Role of interventional radiology in the management of critical limb ischemia]. / Prise en charge de l'ischémie critique par la radiologie interventionnelle.

Critical limb ischemia is a growing public health problem with major human and medical costs. Primary amputation is the rule in most countries and hospitals, but has major functional, psychological and financial consequences. By using a combination of endovascular and surgical techniques, it is now possible to save 9/10 limbs at risk. Because of the frequency of atheromatous disease in these patients, often involving the carotid and coronary networks, aggressive management of risk factors and close surveillance are mandatory. The first step, on which subsequent management depends, is the anatomical workup. Arteriography is currently the only technique that offers a robust workup and, in most cases, permits interventional radiology procedures under local anesthesia and during the same session. Various techniques can be used, depending on the type of lesions, from plain balloon angioplasty to stenting, subintimal recanalization, and use of a cutting balloon. We review the different interventional radiology approaches available in this setting, and their results relative to bypass surgery.

A 3-year experience with Molecular Adsorbent Recirculating System (MARS): our results on 63 patients with hepatic failure and color Doppler US evaluation of cerebral perfusion.

In our 3-year experience, we treated 63 patients with Molecular Adsorbent Recirculating System (MARS). The patients were divided as follows: 10 primary non-function (PNF) 16%, 10 delayed non-function (DNF) 16%, 16 Fulminant hepatitis (FH) 24%, 23 acute decompensation of chronic liver disease (ACLF) 38%, and 4 hepatic resection 6%. All patients who underwent MARS treatment had bilirubin >15 mg/dL, Glasgow Coma Score between 9 and 11, ammonium >160 microg/dL and non-coagulability. The determining factors taken into consideration for the continuation of MARS treatment were: an improvement in Glasgow Coma Score, and a decrease in ammonium and bilirubin. We also monitored hemodynamic parameters, acid-base equilibrium, and blood gas analysis before and after each treatment. In order to determine patients' neurological conditions, we not only took into account the Glasgow Coma Score, which does not give mathematically precise results but also took into account the fact that patients with hepatic coma had lower cerebral mean velocity in the cerebral arteries than patients without encephalopathy. For this reason, in the last 22 patients we monitored cerebral perfusion, determined by mean flow velocity (Vmean) in the middle cerebral artery. Our results were expressed as mean +/- SD and we analyzed the differences between mean values for each variable, before and after treatment by means of Student's t-test. At the end of treatment, we obtained significant P-values for bilirubin, ammonium, Glasgow Coma Score and creatinine. In 16/20 patients, we could demonstrate a clear correlation between the improvement in clinical conditions (especially neurological status) and improvement in cerebral perfusion, measured by color Doppler US.

MARS (Molecular Adsorbent Recirculating System): experience in 34 cases of acute liver failure.

As reported in the literature, the mortality rates for patients with Acute Hepatic Failure (AHF) approaches 80% in cases in which liver transplantation is not possible. Post-transplant mortality mostly depends on the severity of the neurological condition at the time of the operation (20% in I-II degree coma patients and 44% in III degree coma patients). The primary indications for liver transplantation in AHF are Fulminant Hepatitis (FH)(93%), Subfulminant Hepatitis (5%) and other indications (2%). Other causes of AHF are Primary Non-Function (PNF) and Delayed Function (DF), which occur in 7-10%. Therefore it becomes necessary to monitor the patients with a Liver Support Device to be able to improve the clinical condition of the patients before liver transplantation (LT). In our experience we used the Molecular Adsorbent Recirculating System (MARS) (MARS Monitor; Teraklin AG, Rostock Germany), which enables the selective removal of albumin-bound substances accumulating in liver failure by the use of albumin-enriched dialysate. The system is used as a bridging device to orthotopic liver transplantation (OLT) of patients with FHF. We studied 34 patients, including 16 males and 18 females: 9 were affected by Primary-Non-Function (PNF), nine by Fulminant Hepatitis (FH), six by Delayed-Non-Function (DNF), and ten by Acute on Chronic Hepatic Failure (AOCHF). The average age of the patients was 41.8 years and the average number of applications was 6.4; the median length of application was about eight hours. The parameters that we monitored, before and after each treatment, were neurological status (EEG, cerebral CT, Glasgow Coma Score), haemodynamic parameters, acid base equilibrium, and blood gas analysis. We also monitored hepatic and renal function. In addition, the clinical conditions of the patients were monitored using kidney and liver ultrasound/ultrasonography (US). Inclusion criteria were bilirubin > 15 mg/dL, ammonia > 160 micro g/dL and a Glasgow Coma Score between 6 and 11. The reduction of bilirubin and ammonia were very significant (P < 0.01), whereas the changes of International Normalized Ratio (INR) were not significant. Also the modifications of albumin, total protein, sodium, potassium and calcium were not significant. In conclusion, four out of nine patients with PNF are alive without a second transplantation and were discharged after about 48 days; four out of nine underwent OLT, while one out of nine died; five out of six patients with DF are alive without a second transplantation, and they were discharged after an average time of 55.5 days, one out of six died; six out of nine patients with fulminant hepatitis underwent OLT and four of these are alive, while two died due to sepsis; three patients are alive without OLT. Four patients with AOCHF underwent OLT and are alive, three patients are alive and on a waiting list, two died while on a waiting list and one patient who experienced reactivation of HBV infection during chemotherapy for non-Hodgkin's lymphoma is alive. In spite of the limited number of cases of our study, we believe that MARS can be applied with high tolerance for a very long period of time. In addition, its repeatability allows it to be used in patients with DNF and FH as a bridge to transplant. In patients with DNF, it is used while waiting for complete recovery of the transplanted organ.