The Short Cardiac Pre-Ejection Period

The influence of pacing on the pre-ejection period.

Pre-ejection period: measuring beta-adrenergic influences upon the heart.

Increasing interest among psychophysiologists in sympathetic (beta-adrenergic) influences upon the heart has created the need for noninvasive techniques for assessing these influences. The validity of pre-ejection period (PEP), a systolic time interval, as a measure of beta-adrenergic influences upon myocardial contractility is evaluated. Details of a procedure for determining PEP using a polyg...

Assessment of left ventricular pre-ejection period in the fetus using simultaneous magnetocardiography and echocardiography.

INTRODUCTION Fetal magnetocardiography (fMCG) is a promising new technique for assessing fetal rhythm; however, no prior studies have utilized fMCG to evaluate human fetal electromechanical physiology. Pre-ejection period (PEP) is an important measure of the electromechanical activation of the heart, and is altered by disease states and arrhythmias. MATERIALS AND METHODS A novel technique was...

Influence of heart rate increase on uncorrected pre-ejection period/left ventricular ejection time (PEP/LVET) ratio in normal individuals.

In 26 normal volunteers, increase in heart rate from mean 73-94 +/- 1-97 to 103-61 +/- 2-72/min, by either intravenous atropine administration or rapid right atrial pacing, produced definite changes in the uncorrected systolic time intervals. As expected, total electromechanical systole (QS2) and left ventricular ejection time (LVET) were shortened, while the pre-ejection period (PEP) was unaff...

Effects of variation in posture and respiration on RSA and pre-ejection period.

The extent to which variation in posture and respiration can confound pre-ejection period and respiratory sinus arrhythmia (RSA) as indices of cardiac sympatho-vagal activity was examined. Within-subjects changes in these measures were assessed in 36 subjects during different postures and (paced) respiratory frequencies. Changes from supine to sitting to standing led to reduced RSA values and l...