Pulmonary arterial hypertension: a comparison between children and adults

Abstract

The characteristics of pulmonary arterial hypertension (PAH), including pathology, symptoms, diagnosis and treatment are reviewed in children and adults. The histopathology seen in adults is also observed in children, although children have more medial hypertrophy at presentation. Both populations have vascular and endothelial dysfunction. Several unique disease states are present in children, as lung growth abnormalities contribute to pulmonary hypertension. Although both children and adults present at diagnosis with elevations in pulmonary vascular resistance and pulmonary artery pressure, children have less heart failure. Dyspnoea on exertion is the most frequent symptom in children and adults with PAH, but heart failure with oedema occurs more frequently in adults. However, in idiopathic PAH, syncope is more common in children. Haemodynamic assessment remains the gold standard for diagnosis, but the definition of vasoreactivity in adults may not apply to young children. Targeted PAH therapies approved for adults are associated with clinically meaningful effects in paediatric observational studies; children now survive as long as adults with current treatment guidelines. In conclusion, there are more similarities than differences in the characteristics of PAH in children and adults, resulting in guidelines recommending similar diagnostic and therapeutic algorithms in children (based on expert opinion) and adults (evidence-based).

FIGURE 1

Paediatric pulmonary arterial hypertension (PAH) diagnostic work-up. CXR: chest radiography; PH: pulmonary hypertension; D_L,CO: diffusing capacity of the lung for carbon monoxide; CT: computed tomography. ^#: if unable to obtain a reliable test in a young child and there is a high index of suspicion for underlying lung disease, the patient may require further lung imaging; ^¶: children >7 yrs of age can usually perform reliably to assess exercise tolerance and capacity in conjunction with diagnostic work-up. Reproduced and modified from reference [114] with permission from the publisher.