Pulmonary hypertension

Symptoms and clinical features

Early symptoms are often subtle and progress slowly. Common complaints include breathlessness on exertion, reduced exercise tolerance, fatigue, lightheadedness or syncope (fainting), chest discomfort, and swollen ankles or abdomen from fluid retention. Symptoms typically worsen with physical activity. Because findings can be non‑specific, diagnosis is sometimes delayed.

Causes and pathophysiology

PH can result from diverse processes that increase resistance in the pulmonary circulation or raise pressure in the left heart. Major categories include pulmonary arterial disease (narrowing or remodeling of small arteries), left heart disease, chronic lung disease and hypoxia, chronic thromboembolic disease (organized clots), and miscellaneous or multifactorial causes. Narrowed pulmonary vessels increase vascular resistance, which forces the right ventricle to work harder; over time this can produce right ventricular enlargement and failure, affecting the heart.

Diagnosis

Evaluation aims to confirm elevated pulmonary pressures, identify the underlying cause, and assess severity. Typical tests include transthoracic echocardiography (screening), pulmonary function tests, chest imaging, V/Q (ventilation/perfusion) scanning to detect chronic clots, and laboratory studies. Definitive diagnosis and accurate hemodynamic measurement require right heart catheterization. Additional specialized testing is often performed at centers with PH expertise.

Treatment and management

Management combines general measures, targeted drug therapies, and, for selected patients, interventional or surgical options. General strategies include supervised exercise programs, salt restriction, and oxygen supplementation when hypoxia is present; supplemental oxygen is commonly used to reduce hypoxic vasoconstriction (supplemental oxygen). Medications may include diuretics, anticoagulants in selected cases, calcium channel blockers for rare responders, and disease‑modifying pulmonary vasodilators such as prostacyclin analogs, endothelin receptor antagonists, and phosphodiesterase‑5 inhibitors. Patients with advanced, refractory disease may be evaluated for lung transplantation (lung transplant) or combined heart–lung transplantation (heart–lung transplant).

Prognosis and notable considerations

Prognosis depends on the cause, stage at diagnosis, and response to therapy. Early recognition and treatment can improve symptoms and outcomes. PH is managed best in multidisciplinary centers that can perform the full diagnostic workup and offer modern therapies. Distinguishing PAH from PH due to left heart disease, lung disease, or chronic thromboembolism is crucial because treatment and prognosis differ substantially.

• Key points: PH is not a single disease but a group of conditions that elevate pulmonary arterial pressure.
• Right heart function determines symptoms and long‑term outlook.
• Referral to specialized centers improves diagnostic accuracy and access to targeted treatments.