Acute pericarditis, unspecified

This code represents an acute inflammation of the pericardium, the sac surrounding the heart, without further specification of its cause or type. It indicates a sudden onset of pericardial inflammation, often presenting with chest pain, pericardial friction rub, and characteristic EKG changes.

Use this code when the medical record clearly documents a diagnosis of acute pericarditis, but the specific etiology (e.g., viral, bacterial, autoimmune) is not identified or documented. It is appropriate for initial encounters where the cause is still under investigation or when the physician explicitly states "acute pericarditis, unspecified."

• Do not use this code if a more specific type of acute pericarditis (e.g., viral, infectious, recurrent) is documented; always code to the highest level of specificity.
• Ensure documentation supports "acute" presentation; chronic pericarditis has a different code.
• Consider co-morbidities or underlying conditions that may be the cause of the pericarditis and code them appropriately as additional diagnoses.