Abstract
Background The left ventricular (LV) diastolic performance of infants who were in a stable post-treatment condition in the neonatal intensive care unit was evaluated using echocardiography. Methods and Results The study group comprised 55 infants (Stable infant group, SI) and the parameters of LV performance were: LV propagation velocity (Vp) by color M-mode Doppler echocardiography (CMD), peak E wave, peak A wave, and the E/A ratio of transmitral flow. In a second set of measurements, a subset of 10 infants (patent ductus arteriosus (PDA) infant group, PI) were evaluated for LV diastolic performance during closure of PDA. The mean Vp in the SI was 27.2±7.3 cm/s and a positive correlation was observed between Vp and gestational age (r=0.477, p=0.0002). In the PI, Vp did not change significantly during closure of the PDA (from 23.3±8.2 cm/s to 27.5±8.4 cm/s); however, the E/Vp ratio decreased significantly with closure (from 3.14±0.83 to 2.12±0.68, p=0.0051). Conclusion The measurement of Vp by CMD can be considered a parameter for the evaluation of LV diastolic performance, even in the neonatal period. The LV diastolic performance of the infant is maintained from immediately after birth to spontaneous closure of the PDA. (Circ J 2005; 69: 1094 - 1098)
