Differences in Pulmonary Artery Stiffness Measured by CMR in Preterm-Born Young Adults With and Without Bronchopulmonary Dysplasia

BACKGROUND: Very preterm-born infants are at risk for developing bronchopulmonary dysplasia (BPD), a chronic lung disease. Nowadays, the majority of these infants reach adulthood. Very preterm-born young adults are at risk for developing pulmonary arterial (PA) hypertension later in life. An early sign of PA hypertension is increased PA stiffness. This study aims to use cardiovascular magnetic resonance to compare PA stiffness using PA relative area change (RAC) and pulse wave velocity (PWV) to identify early signs for PA hypertension in young adults born very premature, with and without BPD. METHODS: Twenty preterm-born young adults with and 20 without BPD underwent cardiovascular magnetic resonance and were compared with 20 at-term-born young adults. RAC was calculated as the percentage change between the maximal and minimal areas of the PA. PWV was calculated using a method that simultaneously compares flow and area increase in the pulmonary artery during early systole. RESULTS: In 57 of 60 patients, PWV and RAC measurements could be performed. Preterm-born young adults with BPD showed increased PWV compared with preterm-born young adults without BPD (median [25th-75th percentile] 2.07 m/s [1.45-3.05] versus 1.61 m/s [1.18-1.85]; P=0.04) and at-term-born young adults (1.35 m/s [1.08-2.23]; P=0.04). RAC was decreased in both preterm-born young adults with (62% [56-82]; P<0.01) and without BPD (78% [67-93]; P<0.01), compared with at-term-born young adults (101% [87-122]). CONCLUSIONS: Preterm-born young adults with BPD show increased PA stiffness as measured by PWV compared with preterm-born young adults without BPD and at-term-born young adults; RAC was decreased in both preterm-born groups compared with at-term controls. This noninvasive method of measuring PA stiffness might be a valuable tool to identify individuals at risk for early signs of PA hypertension in this population.