Case of the Month: New fistula but low flow?

61-year-old Caucasian male. History of end stage renal disease on dialysis secondary to diabetic nephropathy, coronary artery disease s/p CABG 2015 presented for fistulo-gram to determine the cause of low flows on hemodialysis. He had recently undergone revision of his left brachio-cephalic fistula. Three weeks later the patient underwent a pacemaker implantation for advanced heart block. The pacemaker was placed using a left brachial vein access site above the left arm fistula. Shortly after the patients flow rates were found to be in the 368cc/min with hemodialysis resulting in more difficulty dialyzing the patient effectively.

Patient underwent left brachio-cephalic fistula assessment revealing a normal arterial reflux study and normal flow through the inflow and fistula. The outflow of the venous system revealed a severe high-grade fibrotic focal obstructive stenosis (figure 1).

Figure 1. High grade stenosis of the left cephalic vein
Figure 1. High grade stenosis of the left cephalic vein

At this time a 7 French sheath was placed into the left cephalic vein. Pre-dilatation was performed using a 5mm balloon. 24 atmospheres of pressure was required to resolve the narrowing (figure 2,3). Final balloon angioplasty was performed using a 7mm drug coated balloon to achieve an excellent angiographic result (figure 4). Later that day flow on dialysis increased by >30% with flows seen at 570cc/min.

Figure 2. Highly resistant lesion despite high atmospheric balloon pressure
Figure 2. Highly resistant lesion despite high atmospheric balloon pressure
Figure 3. Fully inflated balloon resulting in the stenosis yielding
Figure 3. Fully inflated balloon resulting in the stenosis yielding
Figure 4. Successful drug coates balloon angioplasty result
Figure 4. Successful drug coates balloon angioplasty result

Discussion:

Implanted cardiac device related vein stenosis is a relatively common occurrence. Despite this, it is usually asymptomatic. Patients can however, present with ipsilateral symptoms for example pain, swelling, parasthesias, or even altered flow dynamics in a dialysis access fistula resulting in inadequate hemodialysis or worse loss of the surgical conduit. Balloon angioplasty to alleviate the stenosis is associated with a high procedural success and low complication rates. This method however, is associated with low long-term patency due to fibrotic and resistant lesions as well as vascular recoil. Drug coated balloons have recently gained FDA approval for AV access intervention. By reducing neo-intimal hyperplasia and therefore restenosis. Increased patency rates are seen thereby lowering the need for repeat intervention. Stenting is a viable option that does improve longer-term outcomes however data in this area is limited. In circumstances where a dialysis access AV fistula or graft is already present or planned to be placed in the same arm, it is advisable to have a multi-disciplinary conversation between the device implanting physician, vascular surgeon and nephrologist to determine the best course of action to ensure potential short and long term complications can be mitigated or avoided.