TY - CHAP M1 - Book, Section TI - Pulmonary Arterial Hypertension A1 - Moote, Rebecca A1 - Attridge, Rebecca L. A1 - Levine, Deborah J. A2 - DiPiro, Joseph T. A2 - Yee, Gary C. A2 - Posey, L. Michael A2 - Haines, Stuart T. A2 - Nolin, Thomas D. A2 - Ellingrod, Vicki PY - 2020 T2 - Pharmacotherapy: A Pathophysiologic Approach, 11e AB - KEY CONCEPTS Pulmonary arterial hypertension (PAH) is defined as a mean pulmonary artery pressure (mPAP) ≥25 mm Hg at rest with a pulmonary wedge pressure or left ventricular end-diastolic pressure (LVEDP) ≤15 mm Hg and a pulmonary vascular resistance (PVR) >3 Wood units (WU) measured by right cardiac catheterization. Patients with PAH present with exertional dyspnea, fatigue, weakness, and exertion intolerance. As the disease progresses, symptoms of right heart dysfunction and failure, such as dyspnea at rest, lower extremity edema, chest pain, and syncope, may be present. The definitive diagnosis of PAH is done with a right heart catheterization. The right heart catheterization provides important prognostic information and can be used to assess pulmonary vasoreactivity prior to initiating therapy. Goals of treatment are to alleviate symptoms; improve quality of life, functional class, and exercise capacity; slow disease progression; and improve survival. Nonpharmacologic therapy, including counseling on pregnancy avoidance, immunizations, and low-sodium diets, should be provided to all patients with PAH. Conventional therapy of PAH includes oral anticoagulants, diuretics, oxygen, and digoxin. Prostacyclin analogs such as epoprostenol, treprostinil, and iloprost induce potent vasodilation of pulmonary vascular beds and are typically reserved for WHO functional class III and IV patients. Only epoprostenol has demonstrated improved survival. Patients with WHO functional class II or III are commonly initiated on oral therapy for PAH. Options include endothelin-receptor antagonists, phosphodiesterase-5 inhibitors, riociguat, and selexipag. These agents have been shown to improve exercise capacity, functional class, and hemodynamics in PAH. Calcium channel blockers are only considered in a small number of patients who have a positive response to acute vasoreactivity testing. A very small number of patients have a long-term response to calcium channel blockers. Combination therapy may address more than one mechanism causing PAH. Combination therapy may be initiated sequentially or as the initial regimen in patients with worse functional classes. Evidence demonstrates that initial combination therapy is associated with a significant reduction in time to clinical failure and PAH hospitalizations. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/04/18 UR - accesspharmacy.mhmedical.com/content.aspx?aid=1182435532 ER -