021R0KB
Bypass Pulmonary Artery, Left to Subclavian with Nonautologous Tissue Substitute, Open Approach
Procedural Specifications
| Clinical Axis | Detail Definition |
|---|---|
| Section | 0 Medical and Surgical |
| Body System | 2 Heart and Great Vessels |
| Operation | 1 Bypass |
| Body Part | R Pulmonary Artery, Left |
| Approach | 0 Open |
| Device | K Nonautologous Tissue Substitute |
| Qualifier | B Subclavian |
Operation Definition
Altering the route of passage of the contents of a tubular body part
Procedure Overview
Bypass procedures on the heart and great vessels reroute blood around a blocked or narrowed segment of a coronary artery or great vessel, restoring blood flow to tissue that would otherwise be starved of oxygen. Coronary artery bypass grafting is the best-known example, where a segment of the patient's own vein or artery, or a synthetic conduit, is connected from the aorta to a point on a coronary artery past a blockage, giving blood a new path around diseased, narrowed vessel. These procedures are performed for significant coronary artery disease or great vessel obstruction that cannot be adequately managed with medication or a less invasive approach like angioplasty.
Bypass is distinct in ICD-10-PCS because the coded body part is the vessel supplying blood (the origin of the bypass) and the qualifier identifies the vessel or structure the flow is being routed to, rather than the blockage itself being treated. The number of vessels bypassed and the conduit material both matter clinically and for coding, since a triple bypass using a mix of arterial and venous grafts is captured as separate codes for each distinct bypass performed.
Anatomy & Axis Detail
Pulmonary Artery, Left
The left pulmonary artery supplies deoxygenated blood to the left lung, and bypass of this vessel is generally reserved for congenital anomalies in which the vessel is absent, atretic, or arises anomalously, requiring a conduit to establish flow from the right ventricle or another central source into the left pulmonary arterial bed. Its close relationship to the ligamentum arteriosum and left main bronchus means the surgeon must carefully plan the conduit's path to avoid compressing airway structures, particularly in small pediatric patients. As with its right-sided counterpart, this bypass is most often one component of a staged congenital reconstruction rather than an isolated adult cardiac procedure. Coding requires documenting the bypass origin, confirming the left pulmonary artery as the distinct laterality-specific target, and specifying the conduit material, since the qualifier and device values depend on these details rather than on the underlying diagnosis.
Approach: Open
Open approach means the surgeon cuts through skin, mucous membrane, or other tissue layers to physically expose the target site to view before performing the procedure. It gives direct visualization and hands-on access, distinguishing it from Percutaneous approaches where instruments pass through a small puncture without exposing the site. Open is typical for procedures needing wide access, such as most laparotomies.
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.
Qualifier: Subclavian
This qualifier designates a subclavian artery as the bypass destination, commonly seen in procedures addressing arch anomalies or peripheral arterial disease affecting the upper limb inflow. It sits alongside the carotid and axillary qualifiers on the same vascular tree, differing by which downstream branch actually receives the graft.
Coding & Documentation
Coders need the operative note to state, for each individual bypass, the proximal origin of the graft, the distal target vessel, and the type of conduit used - internal mammary artery, saphenous vein, radial artery, or synthetic graft - since each of these determines a distinct body part, qualifier, and device value. A common mistake is coding all grafts in a multi-vessel bypass under one code rather than one code per distinct vessel bypassed, since PCS requires each bypass with a different body part or qualifier combination to be reported separately. Documentation should also make clear whether the procedure was done via open sternotomy or a minimally invasive approach, since the approach value changes accordingly, and confirm whether cardiopulmonary bypass (extracorporeal circulation) was used, which is captured with a separate code for the perfusion service itself.