I21.01: STEMI involving left main coronary artery
ST elevation (STEMI) myocardial infarction involving left main coronary artery
Quick Clinical & Billing Summary
What is ICD-10-CM code I21.01? I21.01 represents STEMI involving left main coronary artery. Under official CDC guidelines, this code is billable and specific for claim submission.
Code Hierarchy & Classification
Clinical Guidance & Documentation Standards
Associated Procedures & Medicare RVU Reimbursement
Open RVU Calculator →Typical outpatient and office evaluation procedures frequently billed alongside diagnosis I21.01:
| CPT/HCPCS | Description | Work RVU | Non-Facility Fee | Facility Fee |
|---|---|---|---|---|
| 99213 | Office/outpatient visit, established patient, 20-29 minutes (Low MDM) | 1.30 | $91.69 | $66.79 |
| 99214 | Office/outpatient visit, established patient, 30-39 minutes (Moderate MDM) | 1.92 | $133.61 | $100.21 |
| 96372 | Therapeutic, prophylactic, or diagnostic injection (subcutaneous/intramuscular) | 0.17 | $18.34 | $12.44 |
CPT Modifier & Billing Rules
Append when a significant, separately identifiable evaluation and management service is provided on the same calendar day as a minor surgical procedure or injection.
Identifies procedures or services not normally reported together but distinct under the clinical circumstances. Use CMS X-modifiers (XE, XS, XP, XU) where required by Medicare.
Frequently Asked Questions about I21.01
Is I21.01 a billable ICD-10 code?
Yes, I21.01 is a valid, billable and specific ICD-10-CM code. It can be reported as a primary or secondary diagnosis on medical claims.
What is the ICD-10 code for STEMI involving left main coronary artery?
The primary ICD-10-CM code for STEMI involving left main coronary artery is I21.01.
What is the effective date of the current I21.01 code?
The code is active for fiscal year FY2027, effective starting 2026-10-01.
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