Diagnosis and Treatment of Pulmonary Hypertension

Abstract

Pulmonary hypertension (PH) is a hemodynamic and clinical state defined as an increase in mean pulmonary arterial pressure ≥25mmHg at rest. Five groups of patients have been defined: group 1 as pulmonary arterial hypertension (PAH), group 2 as PH due to left heart disease, group 3 as PH due to lung diseases, group 4 as chronic thromboembolic PH, and group 5 as PH of other causes. PAH is a rapidly progressive and fatal disease with an incidence of 3 cases per million whereas incidence of PH due to left ventricular dysfunction is as high as 60-70% of all cases. Pulmonary capillary wedge pressure, invasively measured at rest, has been used to distinguish between pre-(≤15mmHg) and post-capillary (>15mmHg) PH. The early clinical symptoms and signs are subtle and non-specific, such as exertional dyspnea, fatigue, pre-syncope and progressive limitation of exercise capacity so the vast majority of patients have an advanced disease with World Health Organization functional class of III or IV at first presentation. The diagnostic approach in PH has the goal to evaluate the two main anatomic components: pulmonary vasculature and right ventricle in order to establish the diagnosis and identify the group of PH. The therapy for PAH patients includes three main components: general measures and supportive therapy; initial therapy with calcium channel blockers in vasoreactive or specific drugs approved for PAH in non-vasoreactive patients either single or in combination, and lung transplantation. All patients with PAH should be referred to PH expert centers for comprehensive diagnostic and therapeutic assessment.