Pediatric Idiopathic Pulmonary Artery Hypertension Clinical Presentation

Infants and children with idiopathic pulmonary artery hypertension (IPAH) usually present with symptoms of low cardiac output. The following may be observed:

• Poor appetite

• Poor growth

• Nausea

• Vomiting

• Lethargy

• Sweating

• Tachypnea

• Tachycardia

Infants who have a patent foramen ovale may also present with cyanosis, either at rest or with exercise, because of a concomitant right-to-left shunt. In infants and children without the atrial level pop-off, syncope can be a presenting symptom that is somewhat ominous. Older children and adolescents tend to present with exertional dyspnea and chest pain. These are the typical symptoms in adults.

Patients with severe IPAH are at risk of pulmonary hypertensive crises. These can result in arrhythmias, syncope, and/or sudden cardiac death.

The physical examination findings are typical of the findings of pulmonary hypertension. Typically, the pulmonic component of the second heart sound is accentuated. A right ventricular heave with or without chest wall distortion may be noted as a result of right ventricular hypertrophy and/or dysfunction. Tricuspid regurgitation is common.

Clinical signs of right heart failure, such as hepatomegaly, peripheral edema, and acrocyanosis, are rare in infants. However, they can be observed in older children and adults.

A classification scheme has been defined, based on the World Health Organization conference on pulmonary hypertension in 2003. The classification system divides pulmonary hypertension into 5 groups, as follows:

1. Pulmonary artery hypertension

2. Pulmonary hypertension with left-sided heart disease

3. Pulmonary hypertension associated with respiratory disorders and/or hypoxemia

4. Pulmonary hypertension due to chronic thrombotic/embolic disease

5. Miscellaneous (eg, sarcoid)

Group 1—pulmonary artery hypertension—comprises the following:

(1.1) Idiopathic pulmonary hypertension

(1.2) Familial

(1.3) Pulmonary hypertension associated with the following:

1. Collagen-vascular disease

2. Congenital heart disease with left-to-right shunt

3. Portal hypertension

4. Human immunodeficiency virus (HIV) infection

5. Drugs (anorexigens or other toxins)

6. Thyroid disorders

7. Other entities (Gaucher disease, hereditary hemorrhagic telangiectasia, hemoglobinopathies)

(1.4) Persistent pulmonary hypertension of the newborn

(1.5) Pulmonary veno-occlusive disease

Group 2—pulmonary hypertension with left heart disease—comprises the following:

(2.1) Left atrial or left ventricular disease

(2.2) Left-sided valvular disease

Group 3—pulmonary hypertension associated with respiratory disorders and/or hypoxemia—comprises the following:

(3.1) Chronic obstructive lung disease

(3.2) Interstitial lung disease

(3.3) Sleep-disordered breathing

(3.4) Alveolar hypoventilation

(3.5) Chronic exposure to high altitude

(3.6) Neonatal lung disease

(3.7) Alveolar-capillary dysplasia

(3.8) Other

Group 4—pulmonary hypertension due to chronic thrombotic/embolic disease—comprises the following:

(4.1) Thrombotic obstruction of proximal pulmonary arteries

(4.2) Obstruction of distal pulmonary arteries

• Pulmonary embolism (thrombus, tumor, parasites)

• In situ thrombosis