PAH (Pulmonary Arterial Hypertension) is classified as group 1 pulmonary hypertension.
According to the provided reference, patients in group 1 are considered to have pulmonary arterial hypertension (PAH), which has several causes, including inheritable causes, drugs, and connective tissue disease. The other groups are:
- Group 2: Due to left-sided heart disease.
- Group 3: Due to chronic lung disorders and hypoxemia.
- Group 4: Due to pulmonary artery obstructions.
