ICD-10-PCS Billable Code

02U94KZ

Supplement Chordae Tendineae to No Qualifier with Nonautologous Tissue Substitute, Percutaneous Endoscopic Approach

Procedural Specifications

Clinical Axis Detail Definition
Section0 Medical and Surgical
Body System2 Heart and Great Vessels
OperationU Supplement
Body Part9 Chordae Tendineae
Approach4 Percutaneous Endoscopic
DeviceK Nonautologous Tissue Substitute
QualifierZ No Qualifier

Operation Definition

Putting in or on biological or synthetic material that physically reinforces and/or augments the function of a portion of a body part

Procedure Overview

Supplement procedures add biological or synthetic material to reinforce or enhance a portion of the heart or a great vessel without removing the existing structure. Common examples include patch repair of a septal defect, reinforcing a weakened area of the aortic wall, or placing material to strengthen a valve annulus during repair.

The goal is to shore up tissue that is present but insufficient on its own, whether because of a congenital hole, an aneurysm that has thinned the vessel wall, or a valve structure that needs extra support to function properly. Unlike a replacement, the body's own tissue stays in place and the added material works alongside it.

Patients typically encounter this term in the context of congenital defect closures, aortic aneurysm repairs, and valve repair techniques that use patches, rings, or other reinforcing materials rather than swapping out the whole valve or vessel.

Anatomy & Axis Detail

Chordae Tendineae

The chordae tendineae are the thin fibrous cords anchoring the mitral and tricuspid valve leaflets to the papillary muscles, preventing prolapse of the leaflets into the atrium during ventricular systole. When chordae rupture or elongate from myxomatous degeneration, infective endocarditis, or ischemic damage, the valve leaflet loses support and regurgitation results. Supplementing the chordae involves reinforcing these native structures with artificial material, most commonly expanded polytetrafluoroethylene (ePTFE) neochordae, sutured between a papillary muscle and the leaflet edge to restore proper coaptation without replacing the valve itself. This is a hallmark of chordal replacement techniques used in mitral valve repair, distinguishing it from resection-based repairs, and the operative note should clearly identify the synthetic loop or strand placement so coders can differentiate this reinforcement from a Repair or Replacement procedure on the valve leaflets themselves.

Approach: Percutaneous Endoscopic

Percutaneous Endoscopic combines a puncture through skin or mucous membrane with insertion of an endoscope to visualize the procedure internally, as in laparoscopic cholecystectomy. It is distinguished from plain Percutaneous by the presence of scope-guided visualization, and from Via Natural or Artificial Opening Endoscopic by its route being a new puncture rather than an existing orifice or stoma.

Device: Nonautologous Tissue Substitute

Nonautologous Tissue Substitute refers to biologic material sourced from a donor or another species, such as an allograft or xenograft, used to replace a body part. It differs from Autologous Tissue Substitute by tissue origin outside the patient's own body, and from Synthetic Substitute by being biologic rather than manufactured material.

Coding & Documentation

Coders assign Supplement when the note documents that material, biological or synthetic, was added to reinforce or augment existing anatomy, such as closing a septal defect with a patch or buttressing a vessel wall. The documentation should identify the material used and confirm that native tissue was not removed and replaced, only strengthened.

The most frequent error is confusing patch closure of a defect, which is Supplement, with actual replacement of a structure, which requires taking out the original part. Another common mistake is missing that some valve repairs combine Supplement for annuloplasty ring placement with Repair for other steps done in the same operative session, each of which needs its own code.

Commonly Confused With

ReplacementSupplement is closely confused with Replacement, where the distinction is whether native tissue is removed, as in Replacement, or left in place and reinforced, as in Supplement.
RepairIt also overlaps with Repair, the default root operation used when no other term fits; if a patch is placed specifically to reinforce or close a defect using added material, Supplement takes priority over Repair.
RestrictionCoders should also distinguish Supplement from Restriction, since a patch that narrows an oversized structure to normal caliber may actually reflect a Restriction if that narrowing is the primary intent rather than reinforcement.