Pulmonary hypertension due to lung diseases and hypoxia

This code signifies elevated blood pressure within the pulmonary arteries that is a direct consequence of underlying chronic lung diseases and/or chronic hypoxia. It represents a specific type of secondary pulmonary hypertension where the primary etiology is respiratory compromise, leading to increased vascular resistance in the lungs.

Apply this code when documentation clearly links pulmonary hypertension to conditions such as COPD, interstitial lung disease, sleep apnea, or other chronic respiratory disorders causing hypoxemia. Supporting documentation should include diagnostic findings of pulmonary hypertension (e.g., echocardiogram, right heart catheterization) and a confirmed diagnosis of the underlying lung disease and/or chronic hypoxia.

• Always code the underlying lung disease(s) and/or hypoxia first, as they are the primary cause.
• Distinguish from pulmonary hypertension due to cardiac disease (Group 2) or thromboembolic disease (Group 4).
• Ensure physician documentation explicitly states the causal link between the lung disease/hypoxia and the pulmonary hypertension.