Analysis of systolic time intervals in normal school children

Abstract

Systolic time intervals (STIs) were measured in 152 normal school children by simultaneous recording of electrocardiogram, phonocardiogram and carotidogram. The influence of factors, such as age, heart rate and blood pressure, upon STI was studied by means of stepwise regression analysis. A highly, significantly negative correlation was observed of QS₂ and LVET with heart rate, a significant positive correlation of PEP, QS₁, ICT, PEP/ LVET and ICT/LVET with age. Regression equations and normal values of STI in school children were derived. No correlation was found of STI with index of heart volume, which suggests that there is no correlation between left ventricular performance and cardiac size in normal school children.

Keywords

systolic time intervals / left ventricular performance / normal values / school children

References

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