Drug-induced pulmonary arterial hypertension: a review

Pulmonary arterial hypertension (PAH) is a subgroup of PH patients characterized hemodynamically by the presence of pre-capillary PH, defined by a pulmonary artery wedge pressure (PAWP) <= 15 mmHg and a PVR >3 Wood units (WU) in the absence of other causes of pre-capillary PH. According to the current classification, PAH can be associated with exposure to certain drugs or toxins such as anorectic agents, amphetamines, or selective serotonin reuptake inhibitors. With the improvement in awareness and recognition of the drug-induced PAH, it allowed the identification of additional drugs associated with an increased risk for the development of PAH. The supposed mechanism is an increase in the serotonin levels or activation of serotonin receptors that has been demonstrated to act as a growth factor for the pulmonary artery smooth muscle cells and cause progressive obliteration of the pulmonary vasculature. PAH remains a rare complication of several drugs, suggesting possible individual susceptibility, and further studies are needed to identify patients at risk of drug-induced PAH.