Other acute myocarditis

This code signifies an acute inflammatory condition of the heart muscle that does not fit into more specific categories of acute myocarditis (e.g., infectious, toxic, or hypersensitivity). It indicates a sudden onset of myocardial inflammation from an unspecified or less common etiology.

Apply this code when documentation clearly states "acute myocarditis" but lacks specific details regarding the underlying cause, or when the cause is identified but does not have a more precise ICD-10-CM code. This is appropriate for cases where the physician has diagnosed acute myocarditis but the specific type (e.g., infectious, toxic) is not documented or is atypical.

• Always seek clarification from the provider if a more specific type of acute myocarditis is suspected but not documented.
• Do not use this code if a definitive cause, such as viral, bacterial, or toxic exposure, is identified and has a more specific code.
• Consider sequencing this code as the principal diagnosis if it is the primary reason for the encounter, or as a secondary diagnosis if it is a co-morbidity.