Pro Fee Coding Tip: AV Fistula

What is a dialysis fistula & how is it utilized for dialysis?

This is a surgically created arteriovenous fistula created by surgically connecting (anastomosis) a large artery and a large vein in the arm. This is done by utilizing a soft synthetic tube. The AV fistula matures when the vein becomes engorged due to arterial blood flow into the venous system (Usually takes 1-2 weeks.) Maturation of the AV fistula is essential. It cannot be used for dialysis until this has happened.

Once the graft heals & matures, then dialysis is done by placing two needles – one on the arterial side of the AV graft and the other on the venous side. AV fistulas are expected to last 3 to 5 years. You may see terms used like “strong thrill,” meaning there is good flow in the graft, or “weak thrill,” meaning there is poor flow in the graft.

Common complications:

• Clotting of the artery or vein (thrombosis)
• Stenosis of the artery or vein
• Steal Syndrome
• Aneurysm formation

AV Aneurysm Formation

An aneurysm is a pathological enlargement of the blood vessel wall resulting from repetitive puncture. False aneurysms are hematomas located outside the vessel wall, formed due to a leaking hole in the artery, most often due to iatrogenic trauma – primarily repeated needle punctures.

An aneurysm is coded as:

• T82.898A Other specified complications of vascular prosthetic devices, implants, and grafts
• I72.1 Aneurysm of artery of upper extremity
• Y83.2 Surgical operation with anastomosis, bypass, or graft as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure

Stenosis & Thrombosis

Thrombosis is the formation or presence of a blood clot in a blood vessel.
Stenosis and thrombosis (caused by stenosis) are the most frequent complications of arterio-venous (av) access for dialysis.

Thrombosis is coded as:

• T82.868A Thrombosis of vascular prosthetic devices, implants, and grafts
• I74.2 Embolism and thrombosis of arteries of the upper extremities
• Y83.2 Surgical operation with anastomosis, bypass, or graft as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure

Stenosis is coded as:

• T82.858A Stenosis of vascular prosthetic devices, implants, and grafts
• I77.1 Stricture of artery
• Y83.2 Surgical operation with anastomosis, bypass, or graft as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure

Steal Syndrome

This is a less common complication than stenosis & thrombosis. Also known as “vascular access steal syndrome” (VASS) or “Dialysis-associated Steal Syndrome” (DASS), refers to vascular insufficiency resulting from an arteriovenous fistula or synthetic vascular graft-AV fistula.

Steal Syndrome is coded as:

• T82.898A Other specified complications of vascular prosthetic devices, implants and grafts
• I99.8 Other disorder of circulatory system
• Y83.2 Surgical operation with anastomosis, bypass or graft as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure

Coding Example

IR Angioplasty Venous
DIALYSIS FISTULAGRAM AND VENOUS ANGIOPLASTY X2
CLINICAL HISTORY: This 52-year-old female has diminished blood flow in a right arm dialysis fistula.

PROCEDURE: The procedure was performed with moderate sedation which was administered and monitored by a nurse under my direct supervision.

Initially, a 5 French angiographic catheter was introduced into the right arm dialysis fistula and the catheter was advanced into the inflow brachial artery. The fistula was studied with nonionic contrast material. There is a recurrent high-grade stenosis in the midportion of the fistula which appears to be comprised of a transposed basilic vein. A moderately severe stenosis is also noted in the right subclavian vein near its junction with the internal jugular vein.

A 7 French vascular sheath was inserted from a separate puncture site to perform angioplasty and that sheath was directed toward the right axilla. An 8-mm diameter angioplasty balloon was used to dilate the recurrent stenosis in the mid humeral region through the sheath. Residual narrowing necessitated further angioplasty with a 9-mm diameter balloon. The subclavian vein stenosis was also dilated with the 9-mm balloon, but additional angioplasty was accomplished with a 12-mm diameter balloon.

Following angioplasty, the dialysis fistula is widely patent with brisk blood flow sites. There were no
complications. Fluoroscopy time was 9.5 minutes with a dose of 72 mGy. Moderate sedation time was 51 minutes.

CONCLUSIONS:

1. Recurrent high-grade stenosis of the midportion of the right arm dialysis fistula.
2. Angioplasty of the recurrent venous stenosis in the fistula with 8mm & 9 mm diameter balloons.
3. Moderately severe right subclavian vein stenosis, dilated with 9 mm & 12 mm diameter balloons.
4. Widely patent arterial anastomosis.

CM Codes:

T82.858A Stenosis of vascular prosthetic devices, implants and grafts
I77.1 Stricture of artery
I87.1 Compression of vein
Y83.2 Surgical operation with anastomosis, bypass or graft as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure

CPT Codes:
35476 Transluminal balloon venous angioplasty
75978 Supervision & interpretation for vein.

Coding Tip: Do not code for both arterial & venous anastomosis angioplasty. The entire graft, both anastomoses & venous outflow in the extremity to the axilla level, is considered part of the same vessel. Only one procedure may be coded in this anatomic region. The native artery away from the arterial anastomosis is considered separately.
If the arm arterial anastomosis only is ballooned, use35475/75962.
If the arterial anastomosis and peripheral zone venous stenosis are also dilated in an upper extremity shunt, only bill the arterial procedure with35475/75962.

References:

2017 ICD-10-CM & CPT Coding Guidelines; Clintegrity 360 Encoder
http://cephalicvein.com/2016/06/cephalic-vein-fistula/