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Coronary artery bypass graft (CABG) is a surgical procedure aimed at improving blood flow to the heart by bypassing blocked or narrowed coronary arteries. This specific CPT® code, 33521, refers to a CABG that utilizes a combination of four venous grafts, which are harvested from the patient's body, typically from the greater saphenous veins in the legs. The coronary arteries are essential as they supply oxygen and nutrients to the heart muscle; any obstruction in these arteries can lead to serious conditions such as ischemic heart disease or myocardial infarction. During the CABG procedure, the surgeon creates a new pathway for blood to flow around the blocked artery, thereby restoring adequate blood supply to the heart. The surgical process begins with the harvesting of the venous grafts, followed by an incision in the chest to access the heart. The sternum is divided, and the ribs are retracted to provide a clear view of the heart. Depending on the technique used, the procedure may be performed using the off-pump coronary artery bypass (OPCAB) method, which allows the surgery to be conducted on a beating heart, or through cardiopulmonary bypass, where the heart is temporarily stopped and blood is rerouted through a machine. The prepared vein grafts are then meticulously sewn into place, connecting one end to the ascending aorta and the other end to the coronary artery beyond the site of blockage. This code is specifically for reporting the use of four venous grafts, and it is important to note that if arterial grafts are also used, they must be reported separately using the appropriate codes for venous grafts.
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The procedure is indicated for patients with significant coronary artery disease characterized by the following conditions:
The CABG procedure using four venous grafts involves several critical steps:
Post-procedure care involves monitoring the patient in a recovery area for any complications. Patients typically remain in the hospital for several days for observation and management of pain, as well as to ensure proper healing of the surgical site. Cardiac rehabilitation may be recommended to aid recovery and improve cardiovascular health. Follow-up appointments are essential to assess the success of the grafts and the overall condition of the heart. Patients are advised on lifestyle modifications, including diet and exercise, to promote heart health and prevent future cardiovascular issues.
| Short Descr | CABG ARTERY-VEIN FOUR | Medium Descr | CORONARY ARTERY BYP W/VEIN & ARTERY GRAFT 4 VEIN | Long Descr | Coronary artery bypass, using venous graft(s) and arterial graft(s); 4 venous grafts (List separately in addition to code for primary procedure) | Status Code | Active Code | Global Days | ZZZ - Code Related to Another Service | PC/TC Indicator (26, TC) | 0 - Physician Service Code | Multiple Procedures (51) | 0 - No payment adjustment rules for multiple procedures apply. | Bilateral Surgery (50) | 0 - 150% payment adjustment for bilateral procedures does NOT apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 2 - Payment restriction for assistants at surgery does not apply to this procedure... | Co-Surgeons (62) | 0 - Co-surgeons not permitted for this procedure. | Team Surgery (66) | 0 - Team surgeons not permitted for this procedure. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | APC Status Indicator | Inpatient Procedures, not paid under OPPS | Type of Service (TOS) | 2 - Surgery | Berenson-Eggers TOS (BETOS) | P2A - Major procedure, cardiovascular-CABG | MUE | 1 | CCS Clinical Classification | 44 - Coronary artery bypass graft (CABG) |
This is an add-on code that must be used in conjunction with one of these primary codes.
| 33533 | MPFS Status: Active Code APC C Physician Quality Reporting CPT Assistant Article Coronary artery bypass, using arterial graft(s); single arterial graft | 33534 | MPFS Status: Active Code APC C Physician Quality Reporting Coronary artery bypass, using arterial graft(s); 2 coronary arterial grafts | 33535 | MPFS Status: Active Code APC C Physician Quality Reporting Coronary artery bypass, using arterial graft(s); 3 coronary arterial grafts | 33536 | MPFS Status: Active Code APC C Physician Quality Reporting CPT Assistant Article Coronary artery bypass, using arterial graft(s); 4 or more coronary arterial grafts | 33141 | Addon Code MPFS Status: Active Code APC C Physician Quality Reporting PUB 100 CPT Assistant Article Transmyocardial laser revascularization, by thoracotomy; performed at the time of other open cardiac procedure(s) (List separately in addition to code for primary procedure) | 33508 | Addon Code MPFS Status: Active Code APC N ASC N1 Illustration for Code Endoscopy, surgical, including video-assisted harvest of vein(s) for coronary artery bypass procedure (List separately in addition to code for primary procedure) | 33530 | Addon Code MPFS Status: Active Code APC C Physician Quality Reporting CPT Assistant Article Illustration for Code Reoperation, coronary artery bypass procedure or valve procedure, more than 1 month after original operation (List separately in addition to code for primary procedure) | 35500 | Addon Code MPFS Status: Active Code APC N CPT Assistant Article Harvest of upper extremity vein, 1 segment, for lower extremity or coronary artery bypass procedure (List separately in addition to code for primary procedure) | 35572 | Addon Code MPFS Status: Active Code APC N ASC N1 CPT Assistant Article Illustration for Code Harvest of femoropopliteal vein, 1 segment, for vascular reconstruction procedure (eg, aortic, vena caval, coronary, peripheral artery) (List separately in addition to code for primary procedure) |
| AS | Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery | 59 | Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25. | 77 | Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | 78 | Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.) | 79 | Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.) | 80 | Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s). | 81 | Minimum assistant surgeon: minimum surgical assistant services are identified by adding modifier 81 to the usual procedure number. | 82 | Assistant surgeon (when qualified resident surgeon not available): the unavailability of a qualified resident surgeon is a prerequisite for use of modifier 82 appended to the usual procedure code number(s). | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | CR | Catastrophe/disaster related | GC | This service has been performed in part by a resident under the direction of a teaching physician | PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days | Q0 | Investigational clinical service provided in a clinical research study that is in an approved clinical research study | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | Q6 | Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area |
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| 2013-01-01 | Changed | Medium Descriptor changed. |
| 2011-01-01 | Changed | Short description changed. |
| 2010-01-01 | Changed | Code description changed. |
| 2008-01-01 | Changed | Code description changed. |
| 1993-01-01 | Added | First appearance in code book in 1993. |
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