Elevation of pulmonary artery (PA) pressure due to pulmonary vascular or parenchymal disease, increased left heart filling pressures, or a combination. Table 127-1 lists etiologies by categories.
TABLE 127-1CLASSIFICATION OF PULMONARY HYPERTENSION ||Download (.pdf) TABLE 127-1CLASSIFICATION OF PULMONARY HYPERTENSION
Pulmonary Arterial Hypertension
Heritable (mutations/familial cases)
Collagen vascular diseases (e.g., scleroderma, SLE, RA)
Congenital systemic to pulmonary shunts (e.g., ventricular septal defect, patent ductus arteriosus, atrial septal defect)
Drugs or toxins (e.g., fenfluramine)
Pulmonary Hypertension Due to Left Heart Disease
Pulmonary Hypertension Due to Lung Disease or Hypoxia
Chronic obstructive lung disease
Interstitial lung disease
Chronic Pulmonary Thromboembolic Disease
Systemic conditions (e.g., sarcoidosis, pulmonary histiocytosis)
Hematologic conditions (e.g., myeloproliferative diseases)
Exertional dyspnea, fatigue, angina (due to RV ischemia), syncope, peripheral edema.
Jugular venous distention, RV lift, increased P2, right-sided S4, tricuspid regurgitation. Peripheral cyanosis and edema are late manifestations.
CXR shows enlarged central PA. ECG may demonstrate RV hypertrophy and RA enlargement. Echocardiogram shows RV and RA enlargement, RV hypertrophy; RV systolic pressure can be estimated from Doppler recording of tricuspid regurgitation. Pulmonary function tests (PFTs) identify underlying obstructive or restrictive lung disease; impaired CO diffusion capacity is common. Chest CT identifies contributing interstitial lung disease or pulmonary thromboembolic disease. ANA titer, rheumatoid factor, anti-Scl-70 antibodies are elevated in specific collagen vascular conditions that can result in pulmonary hypertension. HIV testing should be performed in individuals at risk. Cardiac catheterization accurately assesses PA pressures, cardiac output, and pulmonary vascular resistance, and quantifies underlying congenital vascular shunts; during procedure, response to short-acting vasodilators can be assessed.
Figure 127-1 summarizes a testing approach for pts with unexplained pulmonary hypertension.
An algorithm to assess for causes of pulmonary hypertension. In the absence of an identifiable etiology, idiopathic pulmonary arterial hypertension would be suspected. ASD, atrial septal defect; COPD, chronic obstructive pulmonary disease; HIV, human immunodeficiency virus; IPAH, idiopathic pulmonary arterial hypertension; PDA, patent ductus arteriosus; PFTs, pulmonary function tests; RF, rheumatoid factor; Scl-70, anti-topoisomerase 1 antibodies; V/Q, ventilation/perfusion; VSD, ventricular septal defect.
PULMONARY ARTERIAL HYPERTENSION (PAH)
Uncommon (two cases per million), very serious form of pulmonary hypertension. Most pts present in fourth and fifth decades, female >> male predominance; up to 20% of cases are familial. Major symptom is dyspnea, often with insidious onset. Mean survival <3 years in absence of therapy.