Sympathomimetic appetite suppressants (e.g., diethylpropion, fenfluramine).Methamphetamine (and possibly amphetamines and cocaine).Encodes a set of inhibitors of vascular smooth muscle cell proliferation.Hereditary (e.g., BMPR2 loss-of-function mutation).

Pulmonary arterial hypertension ( Group 1 PH ) The following etiologies are grouped according to the World Health Organization (WHO) classification system for pulmonary hypertension. However, not all pulmonary hypertension is caused by pulmonary arterial hypertension. Pulmonary arterial hypertension is a cause of pulmonary hypertension. Pulmonary arterial hypertension ( PAH): a type of precapillary pulmonary hypertension characterized by loss and obstructive remodeling of the pulmonary vascular bed that results in increased pulmonary arterial pressure (See “Etiology” for underlying causes).Right heart catheterization shows increased PCWP pulmonary vascular resistance is typically normal.Caused by left heart disease and certain multifactorial mechanisms.Results from increased pulmonary venous pressure.Right heart catheterization shows increased pulmonary vascular resistance ( ≥ 3 Wood units) and reduced pulmonary capillary wedge pressure ( PCWP ).Caused by pulmonary arterial hypertension, chronic lung disease, chronic thromboembolism, or certain multifactorial mechanisms.Pulmonary vascular remodeling leads to increased pulmonary vascular resistance.An elevated mean pulmonary arterial pressure ( mPAP ) > 20 mm Hg at rest (normal: 10–14 mm Hg ).See “ Persistent pulmonary hypertension of the newborn ( PPHN)” for information on PH in infants. This article focuses primarily on adult PH. Some patients can develop acute or chronic cor pulmonale, which requires treatment of the underlying cause and, in some cases, acute stabilization. Acute decompensated pulmonary hypertension is a high-mortality complication that can occur and is very challenging to treat, typically requiring intensive care, and in some cases, ECMO and lung transplant. In most cases, evaluation by a PH specialist and referral to specialized centers is recommended. Patients with PAH (i.e., Group 1 PH) usually benefit from treatment with calcium channel blockers and other pulmonary vasodilators, while their benefit is unclear for other groups. Treatment mainly consists of managing the underlying cause of PH and preventing disease progression. Right heart catheterization provides a definite diagnosis by measuring mPAP but is not always required. Echocardiograms are used as an initial noninvasive test to estimate pulmonary artery pressure and to evaluate for right ventricular dysfunction. While PH is often asymptomatic in the early stages, symptoms such as dyspnea on exertion, fatigue, cyanosis, and syncope appear in later stages. Over time, the increase in right ventricular pressure may result in structural changes (e.g., dilation or hypertrophy) or impaired function of the right ventricle, a cardiac condition known as cor pulmonale. PH is divided into five groups based on the underlying causes: pulmonary arterial hypertension ( PAH), left heart disease, chronic lung disease, pulmonary artery obstruction (e.g., due to chronic thromboembolic disease), and unclear multifactorial mechanisms. Pulmonary hypertension ( PH) is defined by an elevated mean pulmonary arterial pressure ( mPAP) > 20 mm Hg at rest.

Pcwp pressure