Early recognition and management of pulmonary arterial hypertension: a case for profiling.

Pul monary arterial hypertension (PAH) is defined as a mean pulmonary artery pressure ≥25 mmHg by right heart catheterization and a pulmonary artery wedge pressure ≤15 mmHg, indicating an absence of left ventricular dysfunction. In many patients, PAH is a progressive disease associated with morbidity and often fatal. 1 The traditional concept of primary versus secondary pulmonary hypertension has been discarded and per recent classification underlying conditions for pulmonary hypertension are classified into five groups. These include Group 1 PAH and Groups 2, 3 and 4 include categories of pulmonary hypertension secondary to left heart disease, hypoxemia and lung disease and pulmonary hypertension due to chronic thromboembolism, respectively. Group 5 includes pulmonary hypertension secondary to diseases where the pathogenesis is unclear and includes sarcoidosis, myeloproliferative disorders and other miscellaneous conditions. 1 A number of conditions with common hemodynamic and pathological features are classified as PAH Group 1. Among these conditions, idiopathic pulmonary arterial hypertension (IPAH-previously known as primary pulmonary hypertension) is a rare disease with poor outcome in the absence of effective therapy. 1 Previous data on prognosis of IPAH from the National Institute of Health registry showed a median survival of 2.8 years. 2 At the time, the only medications available were calcium channel blockers that are effective only in a small minority of patients. 3 Compared to IPAH, which is relatively rare (5.9/million); PAH associated with other group I conditions (APAH), like systemic sclerosis, human immune deficiency virus (HIV) infection, congenital heart disease, hemolytic anemia and portal hypertension is not uncommon. The prevalence of PAH is estimated between 8 to 26.7% in patients with scleroderma 2 to 6% with portal hypertension and 0.5% among HIV patients. Up to 30% of children with congenital heart disease who do not undergo repair develop PAH. In these conditions, the presence of PAH may be associated with devastating results and often, it is the PAH rather than the underlying condition which is responsible for morbidity and mortality. For example, although the incidence of PAH among patients who have HIV infection is 0.5%; the risk is 6-12 times higher compared to the general population and the impact of PAH is high, considering the number of HIV patients globally, and also the fact that PAH may be the direct cause for mortality in 72% of deaths. In the last decade and a half, several advances have been made in elucidating the pathogenesis, genetic associations, …