A 34-years-old Caucasian woman presented several episodes of paroxysmal supraventricular tachycardia (> 200 bpm) associated with dyspnoea, after the onset of post-pregnancy hypertension. She underwent Computed Tomography Angiography (CTA), spectral Doppler sonography and angiography which showed a renal arteriovenous fistula between the renal artery, at the hylum trifurcation point, and an extremely ectatic vein draining into the main renal vein of the right kidney, with two little areas of cortical infarction (25 ml total for a mean kidney volume around 900 ml) respectively on the anterior and inferior sides of the kidney.
The flow of the shunt, measured with Doppler sonography, was more than 600 ml per minute. The arteriovenous communication point was 3 mm wide (Fig. 1).
The patient had no history of renal trauma or recent medical intervention with percutaneous instrumentation.
The renal function was normal (serum creatinine 0,8 mg/dl) with a slight hypokalemia (3,3 mEq/l) and coagulation parameters were within normal limits.
We chose as a device a 4 × 6 mm Amplatzer Vascular Plug II (AGA Medical Corporation).. We performed a simulation of the device placement using a plastic model.
The patient was informed about possible procedural complications, primarily the risk of massive acute right kidney ischemia due to device malpositioning and the consequent nephrectomy necessity, and she gave us consent.
The procedure was performed under general anesthesia. A short 4 F sheath was placed in the right femoral artery for blood pressure monitoring.
Selective right renal artery angiography was performed using a left brachial artery US-guided approach with a 7 F 70 cm long sheath (Flexor Check-Flo, Cook Medical), confirming the AVF beetween renal artery and vein at hylar site.
With a US-guided access in the right internal jugular vein, we reached the renal vein with a 6 F 45 cm long sheath (Flexor Check-Flo, Cook Medical).
From arterial side, a 260 cm long hydrophilic guidewire was passed through the site of communication between artery and vein, reaching inferior vena cava. That guidewire was caught with a 10 mm snare and brought outside the venous sheath.
A 5 F JR4.0 cardiological guiding catheter (Launcher, Medtronic) was carried from the venous side on that guidewire, reaching the artery. After removing the wire, the Amplatzer Vascular Plug II was pushed through the guiding catheter into the artery side and the distal disc was opened in the artery lumen. Then the system (guiding catheter and vascular plug) was pulled-back at the exact level of the arteriovenous communication, anchoring only the distal disc against the arterial wall, inside arterial lumen, and releasing the other two proximal discs inside the venous ectasia (Fig. 2, right).
Immediate significant slowdown of the AVF was obtained, with a good renal vascularization, with contrast media filling the vein only in a late phase (Fig. 3).
As a precaution, a 6 × 40 mm balloon catheter (Armada, Abbott Vascular) was placed uninflated into the renal artery to be ready to manage any haemorragic complication.
An optical coherence tomography (OCT) control was performed from the arterial side, demonstrating the good placement of the device (Fig. 4).
The patient underwent single antiplatelet therapy (acetylsalicylic acid 100 mg die) for 3 months.
The spectral Doppler sonography performed 3 days later confirmed the patency of right renal artery, showing a slight residual slow blood flow through the AVF.
The CTA performed two moths later demonstrated regular patency of the right renal artery and showed a slight residual blood flow through the AVF with a faint early enhancement of the renal vein, with no new ischaemic lesions.
The patient no longer suffered from tachicardia or dyspnoea and the renal function is normal (serum creatinine 0.76 mg/dl 1 year after the procedure).
The CTA control performed 1 year after the procedure showed a slight residual of the AVF, still asymptomatic, with a renal vein ectasia reduction.