Augmented vasoreactivity in adult life associated with perinatal vascular insult

Background Adverse environmental events occurring early in life have receiv ed little attention as predictors of disease in the later stages of life. A t birth, the transition from gas exchange by the placenta to gas exchange b y the lungs requires dramatic changes in the pulmonary circulation, which d uring this period is particularly vulnerable to noxious stimuli. We measure d pulmonary-artery pressure responses to high-altitude exposure, a stimulus that causes pronounced pulmonary vasoconstriction, in young adults who had had transient perinatal hypoxic pulmonary hypertension and in controls of similar age and sex distribution. Methods Review of neonatal-care records at the Lausanne University Hospital for Children identified 15 individuals who met the eligibility criteria (b irth at greater than or equal to 34 weeks of gestation, persistence of hypo xaemia during ventilation with oxygen during the first week of life, and pe rsistence of fetal circulation), Ten of these individuals agreed to take pa rt; the control group was ten volunteers without any history of perinatal c omplications. Systolic pulmonary-artery pressure (by echocardiography) and arterial oxygen saturation were measured at baseline and at high altitude ( 4559 m). Findings The mean increase in pulmonary-artery pressure at high altitude wa s significantly greater (p=0.01) in the participants who had had perinatal pulmonary hypertension (from 26.2 mm Hg [SD 2.1] to 62.3 mm Hg [7.3]) than in the controls (from 25.8 mm Hg [2.3] to 49.7 mm Hg [11.3]). The fall in a rterial oxygen saturation was similar in the two groups. Interpretation These findings suggest that a transient perinatal insult to the pulmonary circulation leaves a persistent and potentially fatal imprint , which when activated in adult life predisposes to a pathological response . Survivors of perinatal pulmonary hypertension may be at risk of developin g this disorder in later life.