Pulmonary hypertension is a complex progressive disorder characterized by elevated pulmonary artery pressure. Diagnosis requires early clinical suspicion based on symptoms such as exertional dyspnea, fatigue, syncope, and chest discomfort, with echocardiography as a first-line diagnostic study. Diagnosis is confirmed using right heart catheterization, with a mean pulmonary artery pressure of 20 mm Hg or more and pulmonary vascular resistance greater than 2 Wood units. Strategies for primary and secondary prevention include regular physical activity, tobacco cessation, weight management, immunizations, and family planning to minimize risks associated with pregnancy. Prevention and evidence-based control of hypertension, diabetes, and dyslipidemia are essential. Occupational and environmental exposures, including poor indoor and outdoor air quality, should be addressed. Advances in pharmacotherapy for pulmonary arterial hypertension that target the endothelin, prostacyclin, and nitric oxide pathways and activin receptor inhibition have improved outcomes. Endothelin receptor antagonists, prostacyclin analogues, and phosphodiesterase 5 inhibitors are key treatment options. Combination therapy is recommended for patients with moderate to severe disease, whereas parenteral prostanoids are indicated for advanced pulmonary arterial hypertension. Right-sided heart failure, a major complication, is managed with fluid management and diuretics, with lung transplant evaluation and palliative shunt procedures considered for refractory cases. Addressing nutrition and iron deficiency are important supportive measures.
Case 1. AC is a 54-year-old patient with exertional dyspnea, fatigue, and lower extremity edema that has progressed over the past 6 months. She has obstructive sleep apnea but uses her continuous positive airway pressure machine inconsistently. Her lungs are clear on auscultation. Computed tomography angiography of the chest, performed during a recent emergency department visit, showed no pulmonary embolism. Echocardiography shows right ventricular hypertrophy, moderate tricuspid regurgitation with an elevated jet velocity of 3.5 m/s (less than 2.9 m/s is normal), and findings suggestive of increased pulmonary artery pressure.
Pulmonary hypertension is defined as an increased mean pulmonary artery pressure (MPAP) of 20 mm Hg or more as measured with resting right heart catheterization.1 Clinicians should suspect pulmonary hypertension in patients with symptoms of exertional dyspnea, progressive fatigue, syncope, pedal edema, or symptoms and signs of left-sided heart disease. Hypoxia at rest or during exertion may also be present.1,2
Pulmonary hypertension is a progressive condition that, if untreated, leads to increased pulmonary vascular resistance (PVR), right ventricular dysfunction, and eventually right-sided heart failure. Increased PVR (often a five- to 10-fold increase) leads to right ventricular hypertrophy and dilatation, which can result in premature death and disability.1–4 Right ventricular function is the primary determinant of prognosis and survival.1
Epidemiology
Pulmonary hypertension affects approximately 1% of the global population and up to 1 in 10 people 65 years and older.3 Pulmonary hypertension was classified into five etiologic groups during the 2018 World Symposium on Pulmonary Hypertension2 (Table 11,2,5).
Table 1 Classifications of Pulmonary Hypertension
| Subcategories | Clinical features | Echocardiography findings | Right heart catheterization findings |
|---|---|---|---|
| Group 1: pulmonary arterial hypertension | |||
| Associated with connective tissue diseases, HIV, portal hypertension, or schistosomiasis Drug- or toxin-induced Heritable Idiopathic | Symptoms/signs of exertional dyspnea, syncope, elevated jugular venous pressure, pedal edema Variable age at onset; relatively younger age (younger than 50 years) and female predominance | Signs of pulmonary hypertension (increased systolic PAP, hypertrophic or enlarged right atrium/ventricle); findings of congenital heart defects | Precapillary pulmonary hypertension (mean PAP > 20 mm Hg, pulmonary arterial wedge pressure ≤ 15 mm Hg, PVR ≥ 3 WU) |
| Group 2: pulmonary hypertension associated with left-sided heart disease | |||
| Heart failure with preserved or reduced ejection fraction Postcapillary pulmonary hypertension secondary to congenital or acquired cardiovascular disease Valvular heart disease | Symptoms/signs of left-sided or valvular heart disease (dyspnea, fatigue, orthopnea, leg edema) Most common in older women who have heart failure with preserved ejection fraction and older men who have heart failure with reduced ejection fraction | Signs of left-sided heart disease and pulmonary hypertension (reduced [≤ 40%] or mildly reduced [41%-49%] left ventricular ejection fraction, increased systolic PAP, enlarged right atrium/ventricle) | Isolated postcapillary pulmonary hypertension (mean PAP > 20 mm Hg, pulmonary arterial wedge pressure > 15 mm Hg, PVR < 3 WU) Combined pre- and postcapillary pulmonary hypertension (mean PAP > 20 mm Hg, pulmonary arterial wedge pressure > 15 mm Hg, PVR ≥ 3 WU) |
| Group 3: pulmonary hypertension associated with lung disease, hypoxia, or both | |||
| Developmental lung disorder Obstructive and/or restrictive lung disease | Chronic hypoxia at rest or during exertion Abnormal findings on pulmonary function testing, chest imaging, and polysomnography | Signs of pulmonary hypertension (increased systolic PAP, enlarged right atrium/ventricle) | Precapillary pulmonary hypertension unless associated with coexisting condition (eg, left-sided heart disease) |
| Group 4: pulmonary hypertension associated with pulmonary artery obstruction | |||
| Chronic thromboembolic pulmonary hypertension Malignant tumors Other pulmonary artery obstructions (eg, benign tumors, arteritis without connective tissue disease, congenital artery stenosis, parasitic infections such as hydatidosis) | Symptoms/signs of pulmonary hypertension (see Group 1) Abnormal findings on ventilation perfusion scan, computed tomography angiography, or both | Signs of pulmonary hypertension (increased systolic PAP, enlarged right atrium/ventricle) | Precapillary pulmonary hypertension unless associated with coexisting condition (eg, left-sided heart disease) |
| Group 5: pulmonary hypertension with multifactorial or unclear mechanisms | |||
| Complex congenital heart disease Hematologic disorders Systemic and metabolic disorders (eg, Gaucher disease, glycogen storage disease, neurofibromatosis, sarcoidosis, chronic kidney failure with or without hemodialysis) | Symptoms/signs of the underlying condition (eg, anemia, metabolic dysfunction) | Varies by etiology | Precapillary pulmonary hypertension (eg, hemoglobinopathies, myeloproliferative disease) Isolated postcapillary or combined pre- and postcapillary pulmonary hypertension |
PAP = pulmonary artery pressure; PVR = pulmonary vascular resistance; WU = Wood units.
Information from references 1, 2, and 5.
Read the full edition
Get immediate access, anytime, anywhere.
Choose a single edition, 1-year or 2-year full-access subscription.
Earn 4 CME credits for this edition.
