PDE5 inhibitors are believed to increase pulmonary artery vasodilation, and inhibit vascular remodeling, thus lowering pulmonary arterial pressure and pulmonary vascular resistance.Tadalafil is taken orally, as well as sildenafil, and it is rapidly absorbed (serum levels are detectable at 20 minutes). The T1/2 (biological half-life) hovers around 17.5 hours in healthy subjects. Moreover, if we consider pharmacoeconomic implications, patients that take tadalafil would pay two-thirds of the cost of sildenafil therapy. However, there are some adverse effects of this drug such as headache, diarrhea, nausea, back pain, dyspepsia, flushing and myalgia. Activators of soluble guanylate cyclase
Soluble guanylate cyclase (sGC) is the intracellular receptor for NO. As of April 2009, the sGC activators cinaciguat and riociguat were undergoing clinical trials for the treatment of PAH. Surgical
Atrial septostomy is a surgical procedure that creates a communication between the right and left atria. It relieves pressure on the right side of the heart, but at the cost of lower oxygen levels in blood (hypoxia). Lung transplantation replaces a chronic condition with the ongoing need for treatment. There is a post-surgical median survival of just over five years.Pulmonary thromboendarterectomy (PTE) is a surgical procedure that is used for chronic thromboembolic pulmonary hypertension. It is the surgical removal of an organized thrombus (clot) along with the lining of the pulmonary artery; it is a very difficult, major procedure that is currently performed in a few select centers.
Monitoring
Established clinical practice guidelines dictate the frequency of pulmonary nodule evaluation and surveillance,
patients are normally monitored through commonly available tests such as:

Prognosis
PAH is considered a universally fatal illness, although survival time may vary between individuals. The prognosis of pulmonary arterial hypertension (WHO Group I) has an untreated median survival of 2–3 years from time of diagnosis, with the cause of death usually being right ventricular failure (cor pulmonale). The survival time is variable and depends on many factors. A recent outcome study of those patients who had started treatment with bosentan (Tracleer) showed that 89% of patients were alive at 2 years. With new therapies, survival rates are increasing. For 2,635 patients enrolled in The Registry to Evaluate Early and Long-term Pulmonary Arterial Hypertension Disease Management (REVEAL Registry) from March 2006 to December 2009, 1-, 3-, 5-, and 7-year survival rates were 85%, 68%, 57%, and 49%, respectively. For patients with idiopathic/familial PAH, survival rates were 91%, 74%, 65%, and 59%. Levels of mortality are very high in pregnant women with severe pulmonary arterial hypertension (WHO Group I). Pregnancy is sometimes described as contraindicated in these women. Epidemiology
The epidemiology of IPAH is about 125–150 deaths per year in the U.S., and worldwide the incidence is similar at 4 cases per million. However, in parts of Europe (France), indications are 6 cases per million of IPAH. Females have a higher incidence rate than males (2–9:1).Other forms of PH are far more common.