Reverse systolic flow in dilated pulmonary arteries demonstrated by colour Doppler imaging

To compare patterns of reverse systolic flow in pulmonary arteries in children with dilated and normal pulmonary arteries.

Retrospective survey.

Tertiary pediatric cardiology referral centre.

Colour Doppler images were reviewed on 45 children, aged three months to 17 years, with normal or dilated main pulmonary arteries. The patients included were unoperated, and had isolated lesions and good parasternal short axis colour Doppler images of the main pulmonary artery with no significant pulmonary insufficiency. There were 19 patients with idiopathic dilation of the pulmonary artery, seven with moderate sized atrial septal defect, seven with moderate pulmonary valve stenosis, two with pulmonary hypertension and 10 children who were normal. Reverse flow was identified by adjacent red and blue areas without aliasing.

Reverse systolic flow extending into early diastole was seen in 27 of the 35 patients and in two of 10 normals (P = 0.003). The main pulmonary artery was substantially dilated in the patient group compared with normals.

Significant reverse systolic flow was found in main pulmonary arteries dilated idiopathically, or from pressure or volume overload. Reverse flow may be related to excessive capacitance of the main pulmonary artery in these patients.