ICD-10 Code I27.841 – Fontan-associated lymphatic dysfunction (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I27.841 – Fontan-associated lymphatic dysfunction
What it is
This code identifies lymphatic complications that occur after Fontan circulation, usually in patients with single-ventricle congenital heart disease. It reflects abnormal lymphatic flow or leakage linked to the Fontan physiology.
Clinical signs
Clinical features vary; refer to documentation. Commonly described findings include pleural or peritoneal fluid accumulation, protein-losing enteropathy, plastic bronchitis, or imaging evidence of abnormal lymphatic channels.
When to use this code
Use this code when the provider documents Fontan-associated lymphatic dysfunction, lymphatic failure, or a related lymphatic complication attributed to Fontan circulation. It may also apply when advanced imaging or specialist evaluation confirms the disorder. Do not code it for nonspecific edema without that linkage.
Do not use for
Do not use this code for general lymphatic disorders, congenital heart disease alone, or postoperative fluid retention without documentation of Fontan-associated lymphatic dysfunction. Check documentation if the note does not clearly connect the lymphatic problem to Fontan physiology.
Coding tip
Confirm the provider explicitly links the lymphatic disorder to Fontan circulation before assigning I27.841.