Left Ventricular Systolic Time Intervals as Indices of Postural Circulatory Stress in Man
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The effects of graded increments of passive head-up tilt on the duration of the systolic time intervals corrected for heart rate were investigated in 15 normal subjects, and three patients with congestive heart failure demonstrated no change in the sydynamic time intervals during head- up tilt.Abstract:
The effects of graded increments of passive head-up tilt on the duration of the systolic time intervals corrected for heart rate were investigated in 15 normal subjects. Head-up tilt caused a prolongation of the pre-ejection period and a shortening of the left ventricular ejection time, while total electromechanical systole diminished minimally. The lengthening of the pre-ejection period and abbreviation of the left ventricular ejection time increased progressively with stepwise increments of head-up tilt. The application of venous occlusive tourniquets produced changes in the systolic intervals directionally similar to those observed with head-up tilt. In contrast to the normal subjects, three patients with congestive heart failure demonstrated no change in the systolic time intervals during head-up tilt. After diuresis in two of the patients with heart failure, the responses of their systolic time intervals to head-up tilt returned toward normal.read more
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References
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Systolic Time Intervals in Heart Failure in Man
TL;DR: It is postulated that a defect in the mechanical performance of the heart is responsible for the abnormal systolic time intervals in human heart failure.
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Bedside technics for the evaluation of ventricular function in man
TL;DR: Characteristic changes in the systolic intervals of the left ventricle have been demonstrated among patients with arteriosclerotic, hypertensive and primary myocardial disease and their use in the bedside evaluation of cardiac performance in man is suggested.
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Contractile State of Cardiac Muscle Obtained from Cats with Experimentally Produced Ventricular Hypertrophy and Heart Failure
TL;DR: It is concluded that congestive heart failure is associated with extreme quantitative abnormalities of the intrinsic contractile state of each unit of heart muscle, which reflect a depression in the intensity of the active state.
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The effect of body position on the circulation at rest and during exercise, with special reference to the influence on the stroke volume.
TL;DR: In 10 healthy, adult, male subjects the hemodynamics have been studied by the aid of heart catheterization at rest and during work both in supine and sitting positions, and the physical working capacity (work performed per heart beat) was of the same order.
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Hemodynamic determinants of the maximal rate of rise of left ventricular pressure.
TL;DR: The maximal rate of left ventricular pressure development was measured in an areflexic preparation which permitted independent control of stroke volume, heart rate, and aortic pressure.