- • Common signs and symptoms: dyspnea on exertion,
syncope–near syncope, chest pain.
- • Accentuated second heart sound, systolic murmur
of tricuspid regurgitation.
- • Evidence of right heart failure: elevated jugular
venous pressure, hepatic congestion, ascites, peripheral edema.
- • Decreased diffusing capacity, hypoxemia.
- • Cardiomegaly and enlarged central pulmonary arteries
on chest radiograph.
- • Enlarged right-sided cardiac chambers on echocardiography.
The pulmonary circulation is usually a low-pressure, low-resistance,
high-capacitance circuit that can accommodate large increases in
blood flow during exercise without significant increases in pressure.
Pulmonary arterial hypertension (PAH) is defined as a resting pulmonary
artery mean pressure >25 or >30 with exercise. Previously, PAH had
been defined as primary pulmonary hypertension (PPH) or secondary
pulmonary hypertension (SPH), but the more general classification
of PAH has now been adopted. PAH is a diagnosis of exclusion and
treatment of PAH targets the underlying cause when present.
Approximately 300–1000 new cases of idiopathic PAH are
diagnosed in the United States each year, although this may be increasing
as a result of increased physician awareness. Women in the third
and fourth decades of life are affected more frequently than men
(1.7:1). Prior to development of effective treatment, median survival
was estimated as 2.8 years from the time of diagnosis with a progressive
decline in functional status until death.
PAH can occur in isolation (idiopathic Primary) or can be associated
with a number of other diseases including connective tissue diseases
(especially scleroderma), advanced parenchymal lung disease with
hypoxemia (ie, interstitial pulmonary fibrosis, emphysema), sleep-disordered
breathing, congenital heart disease, advanced liver disease (portopulmonary
hypertension), human immunodeficiency virus (HIV), and chronic thromboembolic
disease. PAH has also been associated with the use of appetite-suppressive
agents, amphetamines, and intravenous drugs. These diseases are
all associated with increases in precapillary pulmonary arterial
pressure. Other very rare lung diseases cause PAH by increasing
postcapillary pulmonary venous pressure, including pulmonary venoocclusive
disease and pulmonary capillary hemangiomatosis (Table 18–1).
Conditions Associated with PAH. |Favorite Table|Download (.pdf)
Conditions Associated with PAH.
|Connective tissue disease|
|Systemic lupus erythematosus|
|Mixed connective tissue disease|
|Parenchymal lung disease|
|Idiopathic pulmonary fibrosis|
|Chronic obstructive pulmonary disease|
|Congenital left-to-right shunts|
|Atrial septal defect|
|Ventricular septal defect|
|Patent ductus arteriosus|
|Increased pulmonary venous pressure|
|Pulmonary venoocclusive disease|
|Pulmonary capillary hemangiomatosis|
|Left ventricular dysfunction|
|Congestive heart failure|
|Increased left atrial pressure|
|Pulmonary thromboembolic disease|
|Liver disease with portal hypertension|
|Intravenous drug use|
|Exposure to appetite suppressants/amphetamines|
PAH is a common complication of connective tissue diseases, especially
scleroderma and mixed connective tissue disease. PAH can be found
in as many as 60% of patients with the CREST variant
of limited scleroderma (Calcinosis
cutis, Raynaud’s phenomenon, Esophageal dysmotility, Sclerodactyly, and Telangectasias).
The presence of PAH with ...