Cardiac output in newborn infants with transient myocardial dysfunction

Area of Science:

• Neonatal Cardiology
• Pediatric Echocardiography
• Critical Care Medicine

Background:

• Left ventricular myocardial dysfunction is common in neonates, often presumed to cause decreased cardiac output.
• Reliable noninvasive methods for measuring cardiac output in neonates have been lacking.
• M-mode echocardiography diagnoses left ventricular myocardial dysfunction, but cardiac output data is often missing.

Purpose of the Study:

• To measure cardiac output in neonates with left ventricular myocardial dysfunction using pulsed Doppler echocardiography.
• To evaluate the effectiveness of therapy for left ventricular myocardial dysfunction in neonates.
• To establish pulsed Doppler echocardiography as a tool for detecting and managing neonatal myocardial dysfunction.

Main Methods:

• Cardiac output was measured using pulsed Doppler echocardiography in 22 neonates.
• M-mode echocardiography was used to diagnose left ventricular myocardial dysfunction.
• Infants had various conditions including perinatal asphyxia, tachypnea, hypoglycemia, and septic shock.

Main Results:

• Cardiac output and stroke volume were low in 20 out of 22 infants.
• Abnormalities were more pronounced in infants with perinatal asphyxia.
• Dopamine treatment in six infants led to rapid increases in blood pressure, cardiac output, stroke volume, and heart rate, with myocardial contractility normalization within 1 hour.

Conclusions:

• Pulsed Doppler echocardiography is a valuable noninvasive tool for assessing cardiac output in neonates with left ventricular myocardial dysfunction.
• This technique facilitates the detection and evaluation of therapeutic interventions for neonatal myocardial dysfunction.
• Early detection and treatment, as demonstrated with dopamine, can significantly improve outcomes in affected neonates.