I45.81 — Long QT syndrome
I45.81 is a billable, specific ICD-10-CM code for long qt syndrome. It is valid for submission on a claim.
Other codes that can never be billed with I45.81
These codes carry an Excludes1 note pointing at I45.81. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading I45.81 alone.
- R94.31Abnormal electrocardiogram [ECG] [EKG]
Risk adjustment
I45.81 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
I45.81 is named in 32 Medicare coverage policies — 32 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.
- A52423Billing and Coding: Infliximab and biosimilars
- A52458Automatic External Defibrillators - Policy Article
- A52458Automatic External Defibrillators - Policy Article
- A54799Billing and Coding: Urine Drug Testing
How I45.81 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 I45.81.
- Jervell-Lange-Nielsen syndrome
- Romano-Ward syndrome(prolonged QT interval)
- Long›QT syndrome
- Syndrome›Jervell-Lange-Nielsen
- Syndrome›long QT
- Syndrome›QT interval prolongation
- Syndrome›Romano-Ward(prolonged QT interval)
Related codes at this level
Codes that share I45.8. If I45.81 is not quite right, the correct code is usually one of these.
Questions about I45.81
- Is I45.81 a billable ICD-10-CM code?
- Yes. I45.81 is a billable, specific ICD-10-CM code and is valid for submission on a claim.
- Where does I45.81 sit in the tabular list?
- Diseases of the circulatory system (I00-I99), in the block Other forms of heart disease (I30-I5A).