Comparison of the Ejection Time-Heart Rate Relationships in Normal and Ischemic Subjects

Agress, Clarence M.; Wegner, Stanley; Nakakura, Shigeo; Lehman, Eugene H.; Chait, Leonardo

doi:10.1536/ihj.6.497

Cited by 13 publications

(2 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If the slope of the relationship of one variable with another is not altered by an intervention such as exercise, but the position of the curve is shifted; then the regression derived from pooling all the data before and after the intervention will be different from the regressions which are obtained from treating the data separately. This appears to be the explanation for the differences in slope found in the relationship between heart rate and ejection time in previous studies (27)(28)(29)32).…”

Section: Column 5)mentioning

confidence: 62%

Pressure-flow studies in man during atrial fibrillation

Greenfield¹,

Harley²,

Thompson³

et al. 1968

J. Clin. Invest.

View full text Add to dashboard Cite

A B S T R A C T In 13 patients who had atrial fibrillation the ascending aortic pressure-flow relationships were measured by the pressure gradient technique. Both the pressure and flow curves were similar in contour to ones previously obtained by this method. From these recordings, relationships between the phases of systole, the ventricular filling time, and various derived parameters of pressure and flow such as the pulse pressure, stroke volume, peak flow, stroke work, and peak power were evaluated. For stroke volumes greater than 15 cm3 there was little change in the duration of systole in an individual patient. In each patient both the preejection period and the duration of ejection showed a good correlation with stroke volume, peak flow, stroke work, and peak power. When data from all patients were examined, the relationship between stroke volume and duration of ejection was found to be curvilinear and had an overall correlation of r = 0.91. There was marked variation from patient to patient in duration of both the preejection period and systole. Similar correlations between the phases of systole were noted with peak flow, peak power, and stroke work. A positive but mediocre correlation was found between the previous RR interval (an index of ventricular filling time) and the subsequent stroke volume. The correlation, in six patients, between two previous RR intervals and stroke volume was considerably better. The relationship between the pulse pressure and stroke volume was reasonably close except in one patient; however, the group correlation was poor due to differences between individuals.

show abstract

Section: Column 5)mentioning

confidence: 62%

Pressure-flow studies in man during atrial fibrillation

Greenfield¹,

Harley²,

Thompson³

et al. 1968

J. Clin. Invest.

View full text Add to dashboard Cite

show abstract

“…This difference is due to many factors like heart rate, conduction velocity, left ventricular end diastolic volume, left ventricular end diastolic pressure, afterload, and inotropic state of myocardium. Agress et al, (16) stated about the influence of different mode, position, and extent of exercise attributing to differences in the outcome in the STI parameters. Data from experiments of Lance et al, (17) and van der Hoeven et al, (18) showed that shortening of QS2 with Heart rate between 60 to 140 bpm had linear relationship that indicates that with the increase of heart rate the QS2 value decreased and vice versa.…”

Section: Resultsmentioning

confidence: 99%

The effect of mild dynamic exercise on the electromechanical systole of heart in non-athlete, healthy first year medical students of Bengal as a predictive biomarker of arrhythmia

et al. 2022

View full text Add to dashboard Cite

Introduction and Aim: Measurement of Systolic Time Intervals (STIs) is a non-invasive and convenient way of assessing left ventricular electro-mechanical activity. In this study, we assessed effect of mild dynamic exercise on QT, QS2, QT/QS2 ratio, QS2-Index among healthy young first year students at a government medical college of West Bengal, India and compared the same among girls and boys. Materials and Methods: IX-TA-220 multichannel recorder was used to record Electrocardiogram, Phonocardiogram and Carotid pulse tracing among 180 subjects before and after 1 minute of mild exercise with Harvard's Step of 30 cm height with metronome rhythm of 120 beats per minute. Results were analyzed by Microsoft Excel and comparison of each parameter between boys and girls were done using SPSS software in two hemodynamic states. P-value <0.05 was taken as statistically significant. Results: Post exercise mean QT and QS2 shortened and their ratio QT/QS2 increased. There was a statistically significant difference between pre-exercise and post-exercise mean QT, QT/QS2 ratio, QS2 index and significant differences were observed between mean values of the boys and girls. Conclusion: With hemodynamic changes as in exercise, due to sympathetic stimulation & catecholamine release, both QT andQS2 should reduce as all the phases of systole shorten but if QT does not reduce in comparison to QS2 it may lead to arrhythmia in future. Hence QT/QS2 can be a useful pro-arrhythmic biomarker and may complement ECG and Echocardiography in borderline cases.

show abstract

Ejection time — Heart rate relationship during exercise

Lance

Spodick

1976

Cathet. Cardiovasc. Diagn.

View full text Add to dashboard Cite

The slope of the regression equation for left ventricular ejection time (LVET) vs heart rate (HR) is the appropriate factor for correcting LVET for HR. Because the regression relationship varies under different conditions, we determined the LVET-HR equations for subjects (1) seated at rest on a bicycle ergometer, and (2) during uninterrupted bicycle exercise. In 18 normally active male volunteers, ages 22-37, HR and LVET were measured under the two conditions and the regression relationship for LVET on HR determined for each. Regression equations are as follows: (1) LVET = 379-1.8 HR +/- 11.0 for subjects seated at rest on a bicycle ergometer, and (2) LVET = 371-1.2 HR +/- 13.9 for subjects performing upright bicycle exercise. The slope factors (1.8 and 1.2) differed significantly (p less than 0.01). The data indicate that considerable error can result from arbitrarily applying to exercising or resting subjects a correction factor which does not fit the conditions of the data to be corrected.

show abstract

Comparison of the Ejection Time-Heart Rate Relationships in Normal and Ischemic Subjects

Cited by 13 publications

References 2 publications

Pressure-flow studies in man during atrial fibrillation

Pressure-flow studies in man during atrial fibrillation

The effect of mild dynamic exercise on the electromechanical systole of heart in non-athlete, healthy first year medical students of Bengal as a predictive biomarker of arrhythmia

Ejection time — Heart rate relationship during exercise

Contact Info

Product

Resources

About