Q21.15 — Inferior sinus venosus atrial septal defect
Q21.15 is a billable, specific ICD-10-CM code for inferior sinus venosus atrial septal defect. It is valid for submission on a claim.
Inclusion terms
Alternative wordings a physician may use in the chart for this same code.
- Inferior vena cava type atrial septal defect
Risk adjustment
Q21.15 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.
Medicare coverage
Q21.15 is named in 27 Medicare coverage policies — 27 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A52850Billing and Coding: Cardiac Catheterization and Coronary Angiography
- A52850Billing and Coding: Cardiac Catheterization and Coronary Angiography
- A52868Billing and Coding: Transesophageal Echocardiography (TEE)
- A52868Billing and Coding: Transesophageal Echocardiography (TEE)
How Q21.15 is indexed
Coders do not find codes by browsing the tabular list — they look them up in the alphabetic index, under the word the physician wrote. These are the index entries that lead here, so you can see which chart wordings map to Q21.15.
- Defect, defective›atrial septal›sinus venosus›inferior
- Defect, defective›atrial septal›vena cava type›inferior
Related codes at this level
Codes that share Q21.1. If Q21.15 is not quite right, the correct code is usually one of these.
Questions about Q21.15
- Is Q21.15 a billable ICD-10-CM code?
- Yes. Q21.15 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does Q21.15 sit in the tabular list?
- Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0), in the block Congenital malformations of the circulatory system (Q20-Q28).