Early vascular ageingand coupling with deranged cardiac function in preterm fetal growth restricted (FGR) infants.

Abstract

Background: The vascular and cardiac adaptations already present in very preterm FGR infants soon after birth are not known. The objectives were to assess vascular and cardiac morphology and mechanics in very preterm infants with FGR compared to an appropriate for gestational age (GA) cohort using conventional and tissue Doppler echocardiography. Method(s): 20 preterm infants (28-32) GA and birthweight (BW) <10th centile were compared with 20 preterm AGA infants. The abdominal aorta was imaged to measure the aorta intima media thickness (aIMT) and mechanics. Result(s): GA and BW of FGR and AGA infants were 29.8 +/- 1.3 vs. 30 +/- 0.9 weeks (p = 0.78) and 923.4 +/- 168 vs. 1403 +/- 237 g (p < 0.0001). At 10.5 +/- 1.3 days after birth, blood pressure was significantly higher in the FGR infants. The maximum aIMT was 621 +/- 76 vs 479 +/- 54 mum (p < 0.001). Arterial wall stiffness index and peripheral resistance were increased (2.36 +/- 0.24 vs 2.14 +/- 0.24, p = 0.008 and 22.2 +/- 5 vs 13.7 +/- 2.3 mmHg.min. mL.1, p < 0.001). Diastolic dysfunction was evidenced by elevated myocardial performance index and end systolic wall stress (0.34 +/- 0.04 vs 0.25 +/- 0.03, p < 0.001 and 45.9 +/- 6.9 vs. 33.7 +/- 4.2 g/cm2, p < 0.001). Significant correlations between vascular mechanics and cardiac function were noted (Resistance vs E/E' = 0.7 & Tei index = 0.79) Conclusion(s): Arterial and cardiac remodelling in FGR infants may reflect maladaptive coupling and the consequential raised afterload may impair cardiac function and may aid risk stratification.