Cardiology professionals and billing specialists are increasingly under pressure to capture every procedural detail as cardiovascular care grows in complexity. According to the American Heart Association (AHA), between 2020-2021, more than $417.9 billion was spent on cardiovascular disease in the U.S. This included direct medical costs and lost productivity. Error-free coding and billing for cardiology procedures is no longer just optional.
This blog provides a complete list of the top common cardiology CPT codes for 2026, with some billing guidelines, applicable modifiers, and some examples of ICD-10 pairings. Equipping clinicians, coders, and revenue cycle teams with the precision they need in cardiology billing and coding compliance.
Most Common Cardiology CPT Codes 2026
Below are the most frequently used cardiology CPT® codes commonly used for both inpatient and outpatient cardiology services. Each description includes details on medical definition, average length of procedure, billing elements, applicable modifiers, ICD-10 code pairs, and reimbursement/compliance notes.
CPT Code 33945 – Heart Transplantation:
Defined by the AMA, this code represents the complex heart transplantation procedure, including recipient cardiectomy and donor heart implantation. On average, it lasts 4–8+ hours, with ischemic times ideally under four hours. It’s a global surgical service covering the operation and immediate perioperative care. Under CMS reimbursement guidelines, facility and surgeon services must be billed separately.
Only use modifier 22 if there is significant documentation and modifier 59 for unique or unusual circumstances. Typical ICD-10-CM linking: I50.22 (chronic systolic heart failure diagnosis). To remain within the compliance of HIPAA, it is important to maintain complete documentation of the transplant and ensure that a MAC or LCD has pre-authorized the case.
CPT Code 33935 – Donor Cardiectomy:
This CPT® code covers donor heart removal during multi-organ procurement. Timing varies based on donor availability and surgical coordination requirements. Facilities usually handle billing, while surgeons’ professional charges are managed under payer policies.
Modifier usage is expected to be consistent with institutional policy. Coding for the donor heart is – ICD-10-CM: Z52.4 (donor organ for heart), which can be used for all organ donors. Arranging billing per the Organ Procurement Organization (OPO) summary and CMS Medicare reimbursement systems/resources will support procedural accuracy related to billing and documentation details.
CPT Code 33533 – Coronary Artery Bypass Graft (CABG) – Venous Grafts:
This code applies to CABG with a single venous graft. Average duration: 3–6 hours. It’s billed globally under CMS CPT® rules, including anesthesia. Combination modifiers use modifier 51 for multiple procedures, and modifier 22 for greater effort, as indicated by the NCCI rules and regulations.
Coding for this procedure, ICD-10-CM is I25.10 (atherosclerotic heart disease). Documentation standards, especially around the procedure, include graft counts, operative notes, or drafts of the operative report to meet Medicare and Medicaid reimbursement guidelines.
CPT 93458 – Coronary Angiography:
This code is used for imaging supervision and interpretation during coronary angiography with left heart catheterization, as defined by the AMA CPT® manual. Average imaging time: 30–60 minutes. The physician bills the professional component with modifier 26, while the facility bills the technical component under HCPCS codes (Healthcare Common Procedure Coding System). ICD-10-CM pairing: I25.10. Always review CMS local coverage determinations (LCDs) and NCCI bundling rules.
CPT Code 92920 – Percutaneous Balloon Angioplasty:
This code includes percutaneous transluminal coronary angioplasty of one artery with a duration of time between 30 minutes and 3 hours. Please apply the NCCI edits when performing bundled procedures, and apply modifier 59 only when the service is a distinct procedural service. ICD-10-CM: I21.09 (STEMI). Proper coding and documentation in cardiology for payers is essential to prevent payer denials.
CPT Code 33206 – Permanent Pacemaker Insertion:
This code represents that the insertion of a permanent pacemaker with transvenous atrial leads typically takes 1–3 hours. Global period: 90 days. Covered under the Medicare physician fee schedule as a global service. Apply modifier 22 or 59 as needed, respecting E/M Services (Evaluation and Management) rules when same-day visits occur. ICD-10-CM: I49.5 (sick sinus syndrome). Comply with HIPAA and CMS billing rules for device implantation documentation.
CPT Code 93306 – Echocardiography:
This code indicates a full transthoracic echocardiogram with Doppler. Duration: 20–60 minutes. Bill the technical (modifier TC) and professional (modifier 26) components separately when appropriate. Add-on +93325 applies to color Doppler. ICD-10-CM: I35.0 or I50.1. Make sure that the cardiology documentation meets AMA and CMS diagnostic testing criteria for coverage.
CPT Code 93325 – Doppler Echocardiography:
This code is used as an add-on code for color flow velocity mapping during echocardiography; billed alongside 93306. No unique modifiers are required. ICD-10-CM: I42.0 (cardiomyopathy). Document Doppler use per CMS outpatient cardiology testing policy.
CPT Code 93224 – Holter Monitoring (24–48 Hours):
This code represents external ECG monitoring along with physician reading. Time frame: 24-48 hours. Add a modifier of 26. ICD-10-CM: R00.0 or R00.1. Assistance with the integration of outpatient cardiology or documentation if using CMS E/M coding guidelines, verifying the time frame criteria of the payer policy.
CPT Code 93015 – Cardiovascular Stress Test (Exercise):
This CPT code is used to report a complete cardiovascular stress test performed to assess the heart’s electrical and functional response to exercise or induced stress (such as treadmill, bicycle, or pharmacologic agents). The test is performed under ECG monitoring and supervision of a physician during the time-framed test.
Time frame: 30-90 minutes. If coding for interpretation and reporting the procedure with testing service, add modifier 59. ICD-10-CM: R94.31 (abnormal ECG). If documentation includes any type of exercise testing, follow NCCI bundling criteria and CMS coverage.
CPT Code 93017 – Pharmacologic Stress Test:
This CPT code applies to cardiovascular stress testing performed with pharmacologic agents, in situations in which patients cannot participate in an exercise-based stress test because of a physical limitation or medical condition.
With pharmacologic medications such as adenosine or regadenoson, practitioners can simulate the physiological effects of exercise while the myocardial blood flow and heart rate are increased. Time frame: 30-90 minutes. ICD-10-CM: I20.9. When coding an outpatient cardiology service, follow the guidelines of CMS for drug administration to patients.
CPT Code 93018 – Stress Test Interpretation & Report:
This CPT code is used to report the professional interpretation and formal report of cardiovascular stress tests. It represents only the professional component of the service and must be billed separately when the technical portion is performed by another entity.
The corresponding modifier 26 should be appended to indicate interpretation-only billing. The ICD-10-CM code follows the primary diagnosis associated with the stress test, such as I20.9 (angina pectoris) or other ischemic conditions.
CPT Code 93010 – Electrocardiogram (ECG/EKG):
This CPT code is used to bill for the professional interpretation and report of a standard 12-lead electrocardiogram (ECG/EKG). It covers the physician’s diagnostic assessment, while facilities separately report CPT 93005 for the technical tracing component. The typical ICD-10-CM code is R00.0 (tachycardia) or another symptom-based cardiac diagnosis.
CPT Code 93000 – Electrocardiogram ECG/EKG with Interpretation & Report:
This CPT code represents a complete 12-lead electrocardiogram service, including both the tracing and the physician’s interpretation with a signed report. The global service typically takes less than one hour to complete. The most common ICD-10-CM pairing is I48.91 (atrial fibrillation), though other arrhythmia or ischemic codes may apply.
When submitting claims, coders must comply with AMA CPT® professional-component billing standards and CMS technical–professional split guidelines to ensure proper revenue assignment and avoid duplication.
CPT Code 93005 – ECG/EKG, Tracing Only (Technical Component):
This CPT code is used to bill for the technical acquisition of the ECG tracing without interpretation. It applies to facilities or technicians who perform the test but do not provide a diagnostic report. The interpreting physician should separately bill CPT 93010 for the professional component. Claims should follow HCPCS and CMS technical-component billing rules.
CPT Code 93296 – ICD or Pacemaker Device Programming/Interrogation:
This CPT code is used for reporting the programming, interrogation, or follow-up of an implantable cardiac device (e.g., implantable cardioverter-defibrillator (ICD) or permanent pacemaker).
The typical duration for such an encounter is 15-60 minutes, based on the design and complexity of the device and the programming requirements. If billing solely for professional interpretation, modifier 26 should be appended. The applicable ICD-10-CM code is Z45.01 (encounter for adjustment and management of cardiac pacemaker).
CPT Code 93798 – Cardiovascular Stress Testing (Supervised Program):
This CPT code is used to report supervised cardiovascular stress or cardiac rehabilitation sessions coming from an exercise regimen in which a clinician supervises and documents a patient’s physiologic response to structured exercise. Each session will last on average from 30 to 60 minutes, based on the prescribed program. The ICD-10-CM code is Z51.89.
Cardiology Billing Best Practices for Error-Free Claims
Verify Patient Insurance Coverage Before Procedures
The first step before performing any cardiology procedure is to verify the patient’s insurance coverage in detail. This means checking benefits and eligibility, and seeing if any prior authorization is necessary, and whether everything is billed under facility or professional.
It is also very important to check for coverage on any devices or supplies with the payer in advance. Be sure to refer to CMS and any Medicare Local Coverage Determinations (LCDs) before preauthorization, and payer-specific policies to avoid delays or denials on claims.
Accurate Medical Documentation
The second most important step is to ensure any medical documentation is accurate, complete, and in compliance with payers and HIPAA. Clinicians should be documenting the clinical indication for all procedures, detailed operative or test times, all devices used, and have a signed physician interpretation.
High-quality documentation will help affect the use of modifiers (e.g., 25, 22, 59) appropriately and help provide proof if an audit or review of claims requires evidence to show medical necessity.
Use Correct CPT and ICD-10 Codes
The final step in the billing process is to code each procedure and diagnosis accurately. Precise coding requires coders to assign the appropriate CPT® and ICD-10-CM codes that accurately reflect the services performed at the highest level of specificity.
Each coding element should be referenced against the American Medical Association (AMA) CPT® manual, NCCI edits, and CMS coverage requirements before submitting a claim. Correct coding allows for clean claims, quicker payments, and compliance with payer contracts and federal regulations.
Apply Appropriate Modifiers to Cardiology Codes
- Modifier 25 is used for a significant, separately identifiable evaluation and management (E/M) service on the same day as another procedure. Documentation needs to include a significant history, exam, and medical decision-making.
- Modifier 51 is applied when more than one procedure is performed on the same encounter. Payer policy may differ in its use.
- Modifier 52 is used to report reduced services when a procedure has been partially performed. Documentation should clearly explain what led to the reduction in service.
- Modifier 53 is used in cases to show procedures were discontinued, and should include documentation on the record in regard to the reason for the discontinuation.
- Modifier 59 identifies a distinct procedural service that is separate from other services on the same day. There should be caution for the use of Modifier 59 and consideration of the newer, more appropriate X{EPSU} modifiers.
Conclusion
Accurate cardiology CPT codes and strict adherence to AMA/CMS/NCCI billing rules protect clinical integrity and revenue. Clinicians and coders must document procedural details (including realistic procedure times), match precise ICD-10 diagnoses, and apply modifiers only when supported by chart evidence. For practices seeking expert support, Nexus IO provides specialized cardiology billing services to ensure compliance and optimize reimbursement. Don’t forget to stay updated on the 2026 codification by regularly checking AMA CPT updates, CMS LCDs, and MAC bulletins.
