Relationship between the Initial Systolic Time Interval and RR-interval during an exercise stimulus measured with Impedance Cardiography

摘要: The Initial Systolic Time Interval (ISTI), obtained from the electrocardiogram and impedance cardiogram, is considered to be a measure for time delay between electrical mechanical activity of heart reflects an active period cycle. relationship ISTI total cycle (RR-interval) was studied in three groups young, healthy volunteers: low, moderately highly trained subjects. were exposed exercise stimulus on ergometer with increasing work load increase rate. decreased decreasing RR-interval. However, relative proportion ISTI, ISTI/RR, found This inversely proportional. rate this ISTI/RR significantly higher Also, over whole range rates longer these It concluded that can used evaluate cardiac performance during physical non-invasively extramural setting.