What is the most likely cause of pulmonary arterial hypertension in a patient with a positive BMPR2 mutation and a family history of PAH?

The most likely cause of pulmonary arterial hypertension (PAH) in a patient with a positive BMPR2 mutation and a family history of PAH is heritable pulmonary arterial hypertension. BMPR2 (Bone Morphogenetic Protein Receptor Type 2) mutations are known to play a significant role in familial cases of PAH. When a mutation in this gene is present, it disrupts normal signaling pathways that help regulate vascular smooth muscle cell proliferation and apoptosis, leading to increased pulmonary vascular resistance and resultant hypertension.

In cases with a family history, the genetic component is strongly implicated, indicating that the PAH is likely inherited. This aligns with the characteristics of heritable PAH, which includes identifiable genetic mutations and is typically associated with a positive family history of the condition. Given the context provided—that the patient has a positive mutation and a family history—it supports the diagnosis of heritable PAH as the most plausible explanation.

The other options do not fit the context: idiopathic pulmonary arterial hypertension suggests a cause that is not linked to genetic factors, which contradicts the presence of a BMPR2 mutation. Pulmonary venous hypertension typically arises from left heart disease or lung disease and is not classified as PAH. Drug-induced pulmonary hypertension would be the