Standard 12 lead and 24 hour Holter electrocardiographic observation in a biracial group of perinatally asphyxiated newborns.

Abstract

AIM: To compare the cardiovascular responses to perinatal stress between two ethnic groups of newborns. STUDY POPULATION: 23 Nigerians and 14 Dutch perinally asphyxiated newborns together with their respective control of 12 healthy Nigerian and 16 Dutch newborns. METHOD: The study subjects and their controls were evaluated with standard 12-lead and 24-hour Holter electrocardiographic recordings within 36 hours of postnatal life. RESULT: Rhythm, rate, P-wave, P-R interval and QRS duration were normal in study subjects and their respective controls on standard ECG. The prevalence of ST-segment depression in the mid-precordial lead V4 was significantly higher in the asphyxiated Nigerian infants (78%) than in the controls (42%); p < 0.05. Similarly, its prevalence in the Dutch infants (50%) was significanly different from the zero prevalence in the Dutch controls; p < 0.05. Long duration ECG recordings showed a 'fixed heart rate' phenomenon in the asphyxiated infants but not in their controls. CONCLUSION: ST-segment depression may imply myocardial ischaemia in asphyxiated Dutch newborns but such may not be inferred in asphydiated Nigerian newborns. 'Fixed heart rate' phenomenon or loss of sinus arrhythmia appears to be causally related to hypoxaemia which results from perinatal asphyxia.