Longitudinal assessment of atrioventricular annulus excursion by grey-scale m-mode and colour tissue Doppler imaging in premature infants

Abstract

Background: There is a lack of standardized echocardiographic parameters to quantify ventricular function in newborn infants. Long-axis systolic ventricular shortening is a useful parameter of global ventricular function.

Aims: Serial assessment of long-axis systolic atrioventricular annulus excursion in premature infants.

Methods: Two-centre, prospective observational study. Fifty-seven premature infants (26 girls), median (range) gestational age 33(+5) (31(0)-34(+6)) weeks(+days), birth weight 1925 (1127-2836) grams were included. Echocardiographic examinations were performed at the first three days of life and at expected term.

Outcome measures: Systolic annulus excursion by grey-scale m-mode and colour tissue Doppler imaging (cTDI).

Results: A consistent longitudinal pattern was found for annulus excursion by grey-scale m-mode and cTDI. All parameters showed a pronounced increase at expected term (p < 0.001). After normalizing for ventricular size the increase at term was less pronounced. Results were lower by cTDI than by grey-scale m-mode for the left and right ventricular walls (p < 0.001). Intraobserver variability (range 1.5-9.8%) was lower than interobserver variability (5.5-18%).

Conclusions: Serial assessment of longitudinal ventricular shortening in premature infants by grey-scale m-mode and cTDI was feasible and the measurements displayed a consistent pattern. cTDI excursion measurements were lower and more dependent on image quality than m-mode measurements. Lower intraobserver variability suggests that repeated measurements should preferably be performed by the same observer. Annulus excursion varies with ventricular size and we suggest normalizing measurements by ventricular size.

Keywords: Echocardiography; MAE; Premature infant; TAPSE; Transitional circulation; Ventricular function.