I21.21 — ST elevation (STEMI) myocardial infarction involving left circumflex coronary artery
ICD-10-CM
Prior Authorization
No Prior Auth Required
Code is covered without prior authorization (high confidence)
Documentation Required
- The patient's medical record must fully document medical necessity for the cardiac catheterization and support the diagnosis and procedures billed.
- Each claim must include ICD-10-CM diagnosis code(s) that accurately reflect the patient's condition and reason for the procedure and these codes must be linked to the CPT procedure codes on the claim.
- When a referring/ordering physician is required, the name and NPI of the referring/ordering physician must be reported on the claim; for extra-cardiac angiographic services the treating physician's name and NPI must be submitted in items 17/17a of CMS-1500 or electronic equivalent.
- For patients post-heart transplant without evidence of rejection, use primary diagnosis Z09 (follow-up after completed treatment) and secondary diagnosis Z94.1 (heart transplant status); add the underlying disorder code when coding I25.82 or I31.4.
Key Coverage Criteria
- Medicare Part B covers the professional component of cardiac catheterization and coronary angiography when performed in hospital inpatient and outpatient facility settings.
- Diagnostic cardiac catheterization performed in an office setting (where permitted) is covered under Medicare Part B for both professional and technical components.
- Global and technical component procedures are covered under Part B when performed under personal physician supervision in an IDTF, free-standing facility, physician office, or physician-directed clinic (physician present in room for entire procedure).
- Cardiovascular nuclear medicine testing is reimbursable for risk assessment or re-evaluation in asymptomatic patients or patients with stable symptoms who have known atherosclerotic heart disease on catheterization or SPECT perfusion imaging, provided the patient has not undergone a revascularization procedure within the prior 2 years.
- Blood pool scan to assess left ventricular ejection fraction prior to implantation of an implantable cardioverter-defibrillator (ICD) or biventricular pacemaker is covered when the medical record documents the intended plan for device insertion and the test result.
- Simultaneous cardiac function studies using the first-pass technique performed with perfusion imaging (CPT 78451-78454) and reported with CPT 78472 and add-on 78496 are covered when the formal report documents that first-pass cardiac function studies were performed and the laboratory is equipped to perform them.
20 Active Policies
L34761 — Percutaneous Coronary Interventions
J05
A57479 — Billing and Coding: Percutaneous Coronary Interventions
J05
L34636 — Electrocardiographic (EKG or ECG) Monitoring (Holter or Real-Time Monitoring)
J05
A57476 — Billing and Coding: Electrocardiographic (EKG or ECG) Monitoring (Holter or Real-Time Monitoring)
J05
Related Codes
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