Assessment of cardiac performance: short- and medium-term variability of impedance cardiography at rest and during dynamic exercise.
Short- and medium-term variability of impedance cardiography at rest and during exercise at a heart rate of 155-160 beats/min were assessed in 12 healthy men aged 21-28 years. Two consecutive measurements within 1 min were performed 4 times at 2-hour intervals on 2 days 14 days apart. Ejection fraction was the most reproducible of all impedance cardiography parameters, the CV ranging from 3.3-5.9%. The short-term reproducibility of cardiac output and stroke volume at rest was good, the between-repeats coefficient of variation (CV) being 4-6%. The reproducibility weakened with longer time span (between-day CV being about 12%) and higher heart rates (exercise). However, even the between-day reproducibility at rest was as good as that of heart rate. Between-day CV during exercise were about 20%.
Sundberg
S
S
Research Centre, Orion-Farmos, Espoo, Finland.
Akkila
J
J
D000328:Adult; D001794:Blood Pressure / Q000502:physiology; D002302:Cardiac Output / Q000502:physiology; D002307:Cardiography, Impedance / Q000592:standards*; D015444:Exercise / Q000502:physiology*; D006334:Heart Function Tests; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012146:Rest / Q000502:physiology*; D013318:Stroke Volume / Q000502:physiology