ICD-10 Code I31.1 – Chronic constrictive pericarditis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I31.1 – Chronic constrictive pericarditis
What it is
Chronic constrictive pericarditis is long-term scarring and thickening of the pericardium that limits normal heart filling. It causes a stiff, noncompliant sac around the heart.
Clinical signs
Clinical features vary; refer to documentation. Common findings include signs of impaired diastolic filling, such as edema, ascites, jugular venous distention, and reduced exercise tolerance.
When to use this code
Use I31.1 when the provider documents chronic constrictive pericarditis or chronic constriction of the pericardium. The record should support a chronic, established condition rather than an acute pericardial process. Check documentation if the note only mentions pericarditis without constrictive features.
Do not use for
Do not use this code for acute pericarditis, pericardial effusion, or unspecified pericardial disease. If the chart does not clearly state constrictive disease, check documentation.
Coding tip
Verify that “constrictive” is explicitly documented; pericarditis alone does not support I31.1.