PVRI Review

Children with Down's syndrome (DS) are at an increased risk of developing pulmonary arterial hypertension (PAH) due to multiple factors: congenital heart disease (CHD) with persistent left-to-right shunts, chronic upper airway obstruction, abnormal pulmonary vasculature growth, alveolar hypoventilation, and recurrent pulmonary infections. Congenital cardiac defects are reported in 19-43% of cases. With the common lesion is an endocardial cushion defect in 43%. DS and CHD seem to develop PAH at a faster rate and have persistent disease after cardiac surgery compared to non-DS patients with similar defects. The upper airway obstruction is common in DS due to midfacial hypoplasia, macroglossia, narrowing of the nasopharynx, tonsillar and adenoidal enlargement, laryngomalacia, tracheomalacia, and congenital malformations of the larynx and trachea. The incidence of OSA was reported to be in a range of 30-50%. Exacerbating factors including obesity and gastroesophageal reflux may contribute to the occurrence of sleep apnea. In this report, I review the causes of pulmonary hypertension in this population, and its management.