Background and aim Preterm birth has been associated with myocardial remodelling, arrested vascular growth, higher blood pressure and ventricular hypertrophy later in life. The aim of this study was to evaluate left heart structure and function in 6-year-old children born extremely preterm.
Method Children born extremely preterm (EXP; <27 weeks of gestation) in Sweden 2004 to 2007 and matched controls born at term were included. Left ventricular mass index (LVMI), left ventricular end diastolic diameter (LVED) and fractional shortening (FS) were determined by echocardiography. Blood pressure, weight and height were also measured.
Results EXP-children (n = 88; mean GA 25.1 w; BW 817 g) were significantly shorter than controls (mean heights 117.8 and 122.8 cm, p < 0.001). LVMI was 72.1 g/m2 in EXP and 79.6 g/m2 in controls (p < 0.01). LVED in EXP was (43.8 mm/m²) and in controls (42.3 mm/m²; p < 0.05), unadjusted EXP (35.9 mm) and controls (38.7 mm: p < 0.001). FS was 36% in EXP and 35% in controls (n.s). Unadjusted systolic blood pressure was 2.2 mmHg lower in EXP compared to controls (p < 0.05) but this difference disappeared after taking length into account.
Conclusion Although the shape of the heart differed (larger LVED in EXP), there was no left ventricular hypertrophy or other obvious signs of myocardial dysfunction in 6-year-old children born extremely preterm as compared to age-matched controls born at term. Further cardiac follow-up at older age is warranted and analyses of myocardial strain using two dimensional speckle tracking are underway.