ICD-10-CM 2027
ICD-10 code for Sinoauricular block
From the official ICD-10-CM alphabetic index entry “Block, blocked › sinoauricular”. Page updated September 29, 2026.
About coding Sinoauricular block
The ICD-10-CM code for Sinoauricular block is I45.5 (Other specified heart block).
Within I45, choose I45.5 (Other specified heart block) only when documentation doesn't support a more specific option: right fascicular block (I45.0), other and unspecified right bundle-branch block (I45.1), Bifascicular block (I45.2), Trifascicular block (I45.3), nonspecific intraventricular block (I45.4), Pre-excitation syndrome (I45.6), other specified conduction disorders (I45.8) and conduction disorder, unspecified (I45.9).
Don't report I45.5 together with the conditions in its Excludes1 note: heart block NOS (I45.9).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
Don't confuse with (Excludes1 for I45.5)
- heart block NOS (I45.9)
Common questions about Sinoauricular block ICD-10 codes
What is the ICD-10 code for Sinoauricular block?
- I45.5 — Other specified heart block.
Is I45.5 billable?
- Yes. I45.5 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can I45.5 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict I45.5 as a principal diagnosis.
Is I45.5 a CC or MCC?
- No. I45.5 is neither a CC nor an MCC under MS-DRG v44.0.