Prevalence of Congenital Heart Disease and Pulmonary Hypertension in Down's Syndrome: An Echocardiographic Study.

Background: Down's syndrome (DS) is a genetic anomaly, which undergoes increased morbidity and mortality when associated with congenital heart disease (CHD). The aims of the study were to determine the prevalence of CHD and pulmonary hypertension (PH) in DS.

Methods: One hundred twenty-seven patients with DS living in Mexico City were evaluated by physical exam, electrocardiogram and echocardiogram.

Results: CHD was found in 40%. In 80% (n = 102) PH was present [systolic pulmonary artery pressure (SPAP) of 47 ± 19 mm Hg and mean pulmonary artery pressure (MPAP) of 32 ± 11 mm Hg]. Patients with CHD and PH were classified as having 1) no shunt (n = 18) with SPAP of 37 ± 9 mm Hg and MPAP of 25 ± 6 mm Hg and 2) with shunt (n = 26) with PASP of 57 ± 29 mm Hg and MPAP of 38 ± 19 mm Hg (p ≤ 0.001). In those without CHD or with CHD without shunt (n = 76), SPAP was 37 ± 19 mm Hg and the MPAP 25 ± 6 mm Hg. The prevalence of PH in DS was 5.9% at one year and 15% at 10 years. The odds ratio of PH in DS with CHD was 7.3 vs. 3 without CHD.

Conclusion: DS has a high prevalence of CHD and PH. PH prevalence increases when it is associated with CHD. The pathophysiology of PH in DS without CHD should be studied in the near future. Echocardiography is an indispensible tool for evaluation of DS.