General Surgery Coding Alert

Manufacturers may make several type of prostheses, so rely on details, not trade names, to make the proper choice

When reporting endovascular abdominal aortic aneurysm (AAA) repair, the most crucial piece of information you-ll need is the type of prosthesis the surgeon placed. Familiarize yourself with the five available types of prostheses, and you-ll choose the primary code for these procedures in a snap.

Step One: Identify the Artery or Arteries Targeted

As an initial step, you should determine if the surgeon places the prosthesis in the abdominal aorta only, or if a portion of the prosthesis extends into one or more of the iliac (or possibly renal) arteries.

-I would definitely encourage open communication between the surgeons and the medical coders about which specific type of endograft was placed,- says Gary W. Barone, MD, associate professor of surgery at the University of Arkansas for Medical Sciences in Little Rock.

As illustrated (Fig. 1), the abdominal aorta branches into the common iliac arteries below the renal arteries. If the abdominal aorta develops an aneurysm, or bulging due to a weakening of the artery walls, the surgeon may make an incision in the groin and, under fluoroscopic guidance, thread a catheter through the arteries to the aneurysm site. Using a stent, the surgeon will then guide the prosthesis into place via the catheter. When expanded, the prosthesis reinforces the artery wall, which prevents the aneurysm from further ballooning or bursting.

If the graft remains in the abdominal aorta only, without extending into either iliac (or renal) artery (Fig. 2,), you should choose 34800 (Endovascular repair of infrarenal abdominal aortic aneurysm or dissection; using aorto-aortic tube prosthesis), says Roseanne R. Wholey, president of Roseanne R. Wholey and Associates in Oakmont, Pa. This describes placement of a single-piece, tube prosthesis without -docking limbs- (which we-ll discuss later).
Note: If the graft prosthesis does extend into one or more iliac (or renal) arteries, you-ll have to consider a few additional factors before you can choose the appropriate code.

Step Two: One or More Pieces?

If the prosthesis extends into one or both iliac arteries (or possibly a renal artery), you must next determine whether the graft is made of one piece (unibody) or of several pieces that the surgeon places separately and joins together at the aneurysm site (modular).

-Some grafts are required to be constructed within the patient (modular), while others come already as one graft (unibody),- Barone says.

CPT describes two unibody prostheses, which differ according to whether the prosthesis enters one or both iliac arteries.

Code 34805 (- using aorto-uniiliac or aorto-unifemoral prosthesis) describes a tubular graft, much like that described by 34800, except that the graft extends into one iliac artery. -Codes 34800 and 34805 describe closely related procedures,- verifies the AMA's CPT 2004 Changes: An Insider's View, -- the 34800 prosthesis lies only in the aorta and is cylindrical in shape. Alternatively, code 34805 describes a procedure which requires the use of a longer prosthesis that extends into one iliac artery, therefore requiring a tapered cylindrical shape that is smaller in diameter at the distal end- (Fig. 3.1)

Note: You may also report 34805 for a graft that extends downward from a single renal artery (Fig. 3.2).

If the single-piece prosthesis extends from the aorta to both iliac arteries, you-ll choose 34804 (- using unibody bifurcated prosthesis). When in place, this prosthesis looks like an upside-down -Y- (Fig. 4).

Each such prosthesis is custom-made to match the patient's anatomy. The procedure includes passing a special contralateral iliac limb guidewire into the aorta. The surgeon captures the wire using a snare advanced through the arteries from the opposite groin, and she then pulls the contralateral graft limb downward from the aorta into the opposite iliac artery.

Step 3: Count Limbs for Modular Prosthesis

All modular prostheses used for AAA repair extend from the aorta into the iliac arteries. You should report a two-piece graft (in which the surgeon joins a single docking limb extending up from one iliac artery to the main portion of the prosthesis) using 34802 (- using modular bifurcated prosthesis [one docking limb]). -The prosthesis described by code 34802 is constructed of two separate pieces that are joined inside the patient's body during placement to make the ultimate configuration of an inverted -Y,- - says CPT 2004 Changes (Fig. 5.1). 

A three-piece graft consists of one primary portion in the aorta and two docking limbs extending into each iliac artery, all of which the surgeon separately places and joins inside the patient's body to form the upside-down -Y- configuration (Fig. 5.2), Wholey says.

Again, this graft, as described by 34803 (- using modular bifurcated prosthesis [2 docking limbs]), has three pieces, unlike 34804 (single piece) and 34802 (two pieces).

Fenestration, visceral vessels call for Cat. III code: When the surgeon places a modular graft with two docking limbs, but the graft employs small -windows- (fenestration) to allow blood flow to the visceral vessels, CPT instructs you to skip 34803 and instead report category III codes 0078T (Endovascular repair using prosthesis of abdominal aortic aneurysm, pseudoaneurysm or dissection, abdominal aorta involving visceral branches [superior mesenteric, celiac and/or renal artery(s)]).

Step 4: Report Extensions Separately

On occasion, the surgeon may choose to place extension cuffs at the ends of the prosthesis, either because the extension is necessary to reach past the aneurysm or because she has detected an endo-leak at the proximal or distal end(s) of the prosthesis.

You should report an extension(s) placement in the initial vessel using 34825 (Placement of proximal or distalextension prosthesis for endovascular repair of infrarenal abdominal aortic or iliac aneurysm, false aneurysm, or dissection; initial vessel). If the surgeon places extensions in more than one vessel, call on a single unit of +34826 (... each additional vessel [list separately in addition to code for primary procedure]) for each additional vessel affected, Wholey says.

Example: If the surgeon places an extension in a single iliac artery, report one unit of 34825 in addition to the primary prosthesis placement code.

If the surgeon places extensions into each iliac artery, report 34825 and 34826 in addition to the code for the primary prosthesis placement.

Extension often occurs postoperatively: When the surgeon must place extensions due to a leak detected postoperatively and within the 90-day global period of the primary procedure (34800-34804), the AMA recommends appending modifier 78 (Return to the operating room for a related procedure during the postoperative period) to the appropriate extension code(s). Modifier 78 alerts the payer that the return to the operating room was neither planned nor included in the original procedure.

An important point: CPT defines 34825-34826 as -initial- or -additional- vessel, not -initial- or -additional- cuff. From a coding standpoint, only the number of vessels matters -- not the number of cuffs placed -- and you should report multiple cuffs placed in the same vessel only once. For instance, report two cuffs placed in the right iliac artery using 34825 only (because the surgeon repaired only one vessel).

More to come: In the next edition of General Surgery Coding Alert, we-ll discuss appropriate coding for AAA repair-related procedures, including balloon angioplasty, catheter/guidewire placement, artery exposure for prosthesis delivery, fluoroscopic guidance and more.