Echographic ventricular systolic time intervals in normal term and preterm neonates

Area of Science:

• Neonatal physiology
• Pediatric cardiology
• Cardiovascular adaptation

Background:

• Systolic time intervals (STIs) are crucial indicators of cardiac function.
• Understanding STIs in neonates is vital for assessing cardiovascular health.
• Preterm infants may exhibit unique physiological patterns compared to term infants.

Purpose of the Study:

• To compare right ventricular and left ventricular systolic time intervals (RVSTIs and LVSTIs) between normal term and preterm infants.
• To investigate the changes in STIs from early neonatal life up to 90 days.
• To determine the influence of gestational age on LVSTIs.

Main Methods:

• Measurement of RVSTIs and LVSTIs in 2 groups of infants (term and preterm).
• Data collection occurred between 1 hour and 90 days of life.
• Analysis of the ratio of pre-ejection period to ejection time for both ventricles.

Main Results:

• LVSTIs were similar in term and preterm infants during the first five days.
• Preterm infants older than five days showed a lower left ventricular pre-ejection period to ejection time ratio (LPEP/LVET).
• The right ventricular pre-ejection period to ejection time ratio (RPEP/RVET) was lower in preterm infants (0.32) than term infants (0.37) and decreased with age slower than in term infants.

Conclusions:

• Preterm infants exhibit distinct patterns in systolic time intervals compared to term infants after the first week of life.
• The observed differences in RPEP/RVET ratio in preterm infants correlate with lower pulmonary vascular resistance.
• STI measurements provide valuable insights into the cardiovascular adaptation of preterm neonates.