Endovascular Treatment of Renal Arteriovenous Fistula with N-Butyl Cyanoacrylate (NBCA)

Embolisation of a high - flow renal arteriovenous fistula with the use of simultaneous transvenous and transarterial approach and balloon-assisted coil embolization

BACKGROUND

Renal arteriovenous fistula (RAVF) is a rare vascular malformation, which can be asymptomatic or may cause hemorrhage, hypokalaemic hypertension, heart failure and hematuria. Endovascular embolization is a minimally invasive method which can preserve renal parenchyma. In our case, balloon assisted coil embolization with simultaneous transvenous and transarterial approach was used. A remodelling balloon, which is routinely used in neurovascular procedures, was chosen in order to eliminate the risk of coil migration and preserve feeding artery and renal parenchyma.

CASE PRESENTATION

We present a case of successful balloon - assisted coil embolization of a high flow renal arteriovenous fistula in a 25-year-old male patient via simultaneous transarterial and transvenous approach with preservation of the feeding artery.

CONCLUSION

Endovascular embolisation is a safe and effective treatment of RAVFs with low risk of complications. Simultaneous transarterial and transvenous coil deployment with the use of a flow control balloon catheter can eliminate the risk of coil migration and coil protrusion into the parent artery with permanent RAVF occlusion and renal parenchyma preservation.

Renal arteriovenous fistula discovered ~2 years after renal biopsy: A case report

Key Clinical Message

Although percutaneous renal biopsy is considered safe, this invasive procedure has complications such as renal arteriovenous fistula (RAVF). Even if complications such as RAVFs are not observed early after renal biopsy, considering the possibility of delayed renal hemorrhage, follow-up with ultrasound after renal biopsy even in asymptomatic cases could be important.

Abstract

Although percutaneous renal biopsy is considered safe, this invasive procedure can lead to complications such as renal arteriovenous fistula (RAVF). RAVF occurs when some arteries and veins communicate in the absence of capillaries in the renal hilum or renal parenchyma. It was previously thought to be relatively rare; however, with advances in imaging diagnostics, it is sometimes found asymptomatically. In addition, renal biopsy is the most common cause of acquired RAVF. In this case, RAVF was discovered 2 years after renal biopsy. Late-onset RAVF is scarce. This case highlights that even if complications such as RAVFs are not observed early after renal biopsy, considering the possibility of delayed RAVF, follow-up with ultrasound could be important.

Renal arteriovenous fistula complicated with malignant hypertension: a case report

Renal arteriovenous fistula (RAVF) is a rare vascular disease and is usually presented with severe hypertension. Renin-angiotensin-aldosterone system (RAAS) activation was proposed to play a key role in RAVF-induced hypertension but the data was inconsistent. We reported a case of RAVF presented as malignant hypertension, which was detected by contrast-enhanced ultrasonography and successfully managed by interventional embolization. A 35-year-old male was presented with a headache and blurred vision. His blood pressure was up to 220/110 mmHg, with significantly elevated serum creatinine and proteinuria. Hypertensive target organ impairments were noted. A RAVF was detected by contrast-enhanced renal ultrasonography. He underwent renal artery angiography and renal arteriovenous fistula embolization. RAAS activation was also evaluated by separate renal vein sampling. The patient's blood pressure and target-organ damage improved after RAVF embolization and blood pressure control. This is a rare case of renal arteriovenous fistula with malignant hypertension. Contrast-enhanced ultrasonography can be useful for diagnosis.

Fogarty-assisted transcatheter embolization of a large renal high-flow arteriovenous fistula

Background

Renal high-flow arteriovenous fistulas and its complications may involve high output heart failure, hematuria, hypertension or lethal hemorrhage.

Case presentation

This case report covers the case of a 65-year-old male patient with a large renal high-flow arteriovenous fistula of the right kidney (RAVF), treated with balloon-assisted coil and liquid (n-Butyl Cyanoacrylate) embolization. By use of ballon-occlusion with an over-the-wire Fogarty catheter and advancement of a microcatheter through the lumen distal to the balloon during the transcatheter embolization of a high-flow RAVF, control of arterial blood flow is feasible by temporary occlusion of the afferent artery. This technique of flow modulation facilitates controlled deployment of embolization materials and decreases the risk of inadvertent distal embolization by use of only one 6-French (F) arterial sheath.

Conclusions

Balloon-assisted embolization using a Fogarty occlusion catheter represents a feasible, safe and effective treatment option for the treatment of large, high-flow arteriovenous fistulas of the kidney.

Early period results of radiofrequency ablation and cyanoacrylate embolization for great saphenous vein insufficiency

OBJECTIVE

To evaluate the 6 months efficacy and safety of cyanoacrylate closure for the treatment of incompetent great saphenous veins (GSVs) in comparison with radiofrequency ablation (RFA).

METHODS

In this multicenter, retrospective, clinical trial, 398 symptomatic subjects with incompetent GSVs were assigned to either cyanoacrylate closure or RFA. The primary endpoint, complete closure of the target GSV, was determined using duplex ultrasound examination starting from one-, three-, and six-month visits.

RESULTS

All patients were followed for 6 months and there was no difference between the groups in terms of mean follow-up time. Hospital stay and return to work/activity were shorter in the cyanoacrylate ablation (CAA) group, and these differences between the groups were statistically significant. Ecchymosis was observed higher in the RFA group and was statistically significant.

CONCLUSIONS

In this study, in which we examined the CAA and RFA methods, we found that both methods were effective and reliable; however, we found that patients in the CAA group had a more comfortable postoperative period and returned to work earlier.

Minimally invasive electroceutical catheter for endoluminal defect sealing

Surgical repair of lumen defects is associated with periprocedural morbidity and mortality. Endovascular repair with tissue adhesives may reduce host tissue damage, but current bioadhesive designs do not support minimally invasive deployment. Voltage-activated tissue adhesives offer a new strategy for endoluminal repair. To facilitate the clinical translation of voltage-activated adhesives, an electroceutical patch (ePATCH) paired with a minimally invasive catheter with retractable electrodes (CATRE) is challenged against the repair of in vivo and ex vivo lumen defects. The ePATCH/CATRE platform demonstrates the sealing of lumen defects up to 2 millimeters in diameter on wet tissue substrates. Water-tight seals are flexible and resilient, withstanding over 20,000 physiological relevant stress/strain cycles. No disruption to electrical signals was observed when the ePATCH was electrically activated on the beating heart. The ePATCH/CATRE platform has diverse potential applications ranging from endovascular treatment of pseudo-aneurysms/fistulas to bioelectrodes toward electrophysiological mapping.

Renal arteriovenous fistula after renal biopsy: a case report and literature review

Acquired renal arteriovenous fistulas (AVF) are rare conditions in which an anomalous connection arises between the arterial and venous systems. Renal AVFs can be classified into three main groups: idiopathic, congenital, and acquired, the last of which are the most common. Incidence has been increasing, due to the growing number of renal biopsies. Although the renal biopsy procedure is relatively safe nowadays, one possible complication is formation of an AVF in the renal vascular territory. Treatment of renal AVF is widely discussed in the literature and a variety of treatment methods can be employed. We report a case of arteriovenous fistula after renal biopsy that was successfully treated with endovascular coil embolization.

Congenital Renal Arteriovenous Malformation: A Rare but Treatable Cause of Hypertension

BACKGROUND Congenital renal vascular anomalies have been classified into 3 categories: cirsoid, angiomatous, and aneurysmal. These classifications are based on the size, location, and number of vessels involved. Aneurysmal malformations, such as the one reported here, have a single (and dilated) feeding and draining vessel. The prevalence of renal AVMs is estimated at less than 0.04%, making them rare causes of secondary hypertension. CASE REPORT A 29-year-old white woman was seen in the hypertension clinic as a referral from high-risk obstetric clinic for management of hypertension (HTN). A secondary hypertension workup with Doppler waveforms of the renal arteries revealed prominent diastolic flow in the left compared to the right. For confirmation, an MRA was done, which showed a large left renal upper-pole arteriovenous malformation (AVM) with associated vascular shunting and early opacification of the left renal vein. This congenital AVM was identified as the cause of her hypertension. Angiography and coil embolization were performed. The patient's BP normalized within a few days and she was taken off her antihypertensive medications. CONCLUSIONS This case illustrates that a careful review of duplex waveforms beyond just peak velocity and ratios is important to identify uncommon pathologies. This is important, as renal AVMs respond well to embolization, with resolution of hypertension in 59% of patients treated.

Clinical efficacy of absolute ethanol combined with n-butyl cyanoacrylate sclerotherapy in the treatment of Puig's classified advanced venous malformation in children

The aim of the present retrospective study was to investigate the clinical safety and efficacy of absolute ethanol combined with n-butyl cyanoacrylate sclerotherapy in the treatment of Puig's classified advanced venous malformation. Sclerotherapy was performed in 121 children (52 males and 69 females; age range, 5 months to 16 years) with venous malformations under general anesthesia between April 2009 and October 2014 at the Department of Interventional Radiology and Vascular Anomalies, Guangzhou Women and Children's Medical Center, Guangzhou, China. The patients with venous malformations were diagnosed and classified according to the diagnostic criteria of the International Society for the Study of Vascular Anomalies. According to the characteristics of intraoperative percutaneous angiography, 21 patient cases (9 males and 12 females; age range, 6 months to 14 years) were classified as advanced Puig's venous malformation. These 21 patients were treated with absolute ethanol combined with n-butyl cyanoacrylate. The patients were followed-up for 6–24 months (average, 15 months) after treatment. Following treatment with absolute ethanol combined with n-butyl cyanoacrylate, 15 cases were controlled and the total effective rate was 71% (15/21). However, 1 patient developed skin ulcerations, which was classed as a minor complication, 1 patient developed ectopic embolism caused by n-butyl cyanoacrylate reflux, and 1 patient developed transient pulmonary hypertension, the latter two complications were classified as major. Notably, the incidence rate of minor and major complications were 14.3%. To conclude, the present findings indicated that absolute ethanol combined with n-butyl cyanoacrylate sclerotherapy was a safe and effective method with a low complication rate in the treatment of Puig's classified advanced venous malformation in patients.

Comparison of cyanoacrylate embolization and radiofrequency ablation for the treatment of varicose veins

OBJECTIVE

To review clinical outcomes of varicose vein patients treated with cyanoacrylate embolization and radiofrequency ablation at our institution.

METHODS

A retrospective review of patients who underwent cyanoacrylate embolization and radiofrequency ablation during a three-year period. Patient records were reviewed to assess demographics, location and severity of disease, treatment details and outcome at short- and mid-term follow-ups. Outcome parameters included treatment success and complications.

RESULTS

Between January 2014 and December 2016, 335 patients with 476 veins were treated with either cyanoacrylate embolization (n = 148) or radiofrequency ablation (n = 328) at the Vancouver General Hospital Vascular Surgery Vein Clinic. The average age of patients were 57 ± 1 years with the majority being female (78%) and an average BMI of 24.8 ± 0.5. CEAP classes were 2 (49%), 3 (26%), 4a (22%) and >4b (3%). Of the veins treated with cyanoacrylate embolization, the vein types were as follows: 76% were great saphenous vein, 16% were small saphenous vein, 5% were anterior accessory great saphenous vein and 1.4% were perforator veins. The vein types for radiofrequency ablation were 88%, 9%, 3% and 0%, respectively. The average amount of cyanoacrylate embolization delivered for great saphenous vein treatment was 1.8 ± 0.1 ml with a treatment length of 43 ± 1 cm. Subgroup comparison was done for great saphenous vein segments. Treatment success was 100% in cyanoacrylate embolization and 99% in radiofrequency ablation. Superficial phlebitis was the most common complication noted at mid-term follow-up in 5% of cyanoacrylate embolization and 16% of radiofrequency ablation treatments (P < 0.05). One patient in each group had asymptomatic proximal thrombus extension treated with anticoagulation for 2-3 weeks. Three superficial infections from glue clumps were noted in the cyanoacrylate embolization group requiring excision and drainage. Five patients in the radiofrequency ablation group had persistent numbness and one wound complications at the access site.

CONCLUSION

Cyanoacrylate embolization offers equivalent success rates with lower mid-term complication rates as radiofrequency ablation.