ICD-10-CM 2027
ICD-10 code for intraventricular nonspecific block
From the official ICD-10-CM alphabetic index entry “Block, blocked › intraventricular (nonspecific)”. Page updated September 29, 2026.
About coding intraventricular nonspecific block
The ICD-10-CM code for intraventricular nonspecific block is I45.4 (Nonspecific intraventricular block). The official index lists 1 more specific code, so check the documentation for details such as type, cause, site or severity before settling on I45.4.
Within I45 (other conduction disorders), I45.4 is specifically for nonspecific intraventricular block. Related codes cover right fascicular block (I45.0), other and unspecified right bundle-branch block (I45.1), Bifascicular block (I45.2), Trifascicular block (I45.3), other specified heart block (I45.5), Pre-excitation syndrome (I45.6), other specified conduction disorders (I45.8) and conduction disorder, unspecified (I45.9).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 308 (Cardiac Arrhythmia and Conduction Disorders with MCC, relative weight 1.1806), DRG 309 (Cardiac Arrhythmia and Conduction Disorders with CC, relative weight 0.7316) and DRG 310 (Cardiac Arrhythmia and Conduction Disorders without CC/MCC, relative weight 0.568), in MDC 05 (Diseases and Disorders of the Circulatory System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
More specific intraventricular nonspecific block codes (official index)
- bundle branch
- bilateral I45.2 — Bifascicular block
Common questions about intraventricular nonspecific block ICD-10 codes
What is the ICD-10 code for intraventricular nonspecific block?
- I45.4 — Nonspecific intraventricular block. More specific codes apply when the documentation supports them: I45.2.
Is I45.4 billable?
- Yes. I45.4 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can I45.4 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict I45.4 as a principal diagnosis.
Is I45.4 a CC or MCC?
- No. I45.4 is neither a CC nor an MCC under MS-DRG v44.0.