Pulmonary hypertension and idiopathic pulmonary fibrosis: a dastardly duo

Pulmonary hypertension (PH) is a well-recognized complication of interstitial lung disease, including idiopathic pulmonary fibrosis (IPF). The underlying pathogenesis was initially hypothesized to be inflammatory but now is characterized as an over exuberant fibroproliferative process. The prevalence of PH in the setting of IPF has not been well described in the literature, with a reported occurrence from 32% to 85%. Diagnostically, recognizing underlying PH in the setting of IPF remains challenging because of nonspecific clinical symptoms and unrevealing ancillary testing. A high degree of clinical suspicion is paramount. The only reliable diagnostic tool for PH is right heart catheterization. The treatment of PH, in patients with IPF, is based on multiple factors, including disease severity, functional status and degree of hypoxemia. Medications currently approved to treat PH have been administered for PH in the setting of IPF, such as phosphodiesterase-5 inhibitors, nonselective endothelin receptor antagonists and prostacyclin analogues. The treatment of PH in the setting of IPF may also be difficult due to worsening ventilation-perfusion mismatch induced by selective pulmonary artery vasodilator therapy. Lung transplantation should be considered with patients refractory to pharmacological treatment. Identification of PH in IPF patients is crucial, as functional status and prognosis are greatly reduced. Given the high mortality rate and propensity for acute decompensation, IPF and PH patients should be evaluated for transplant early in their disease course.