Cardiac systolic time intervals in fetal monkeys: Ventricular ejection time

1980 ◽  
Vol 136 (5) ◽  
pp. 603-608 ◽  
Author(s):  
Yuji Murata ◽  
Chester B. Martin ◽  
Tsuyomu Ikenoue ◽  
Roy H. Petrie
Keyword(s):  
Systolic Time Intervals ◽  
Ventricular Ejection ◽  
Ejection Time ◽  
Time Intervals ◽  
Systolic Time ◽  
Ventricular Ejection Time

Neonatal Circulatory Changes: An Echocardiographic Study

PEDIATRICS ◽  
1977 ◽  
Vol 59 (3) ◽  
pp. 338-344
Author(s):  
Thomas Riggs ◽  
Stephen Hirschfeld ◽  
Connie Bormuth ◽  
Avroy Fanaroff ◽  
Jerome Liebman
Keyword(s):  
Right Ventricular ◽  
Systolic Time Intervals ◽  
Left Ventricular ◽  
Ventricular Ejection ◽  
Left Ventricular Ejection ◽  
Ejection Time ◽  
Time Intervals ◽  
Systolic Time ◽  
The Right ◽  
Ventricular Ejection Time

Serial echocardiograms were performed in the first three days of life on 38 normal full-term infants. Right ventricular systolic time intervals were measured from the pulmonic valve echogram and left ventricular systolic time intervals were determined from the aortic valve echogram. The heart rate, left ventricular pre-ejection period (LPEP), left ventricular ejection time (LVET), and LPEP/LVET ratio showed insignificant variation with increasing postnatal age. The right ventricular pre-ejection period (RPEP) shortened, the right ventricular ejection time (RVET) lengthened, and the RPEP/RVET ratio decreased with increasing age. The findings suggested that alterations in the RPEP/RVET ratio reflected the decreasing pulmonary artery diastolic pressure and pulmonary vascular resistance of the early neonatal period and may be valuable in the noninvasive evaluation of the newborn's pulmonary vascular bed.

Echographic Ventricular Systolic Time Intervals in Normal Term and Preterm Neonates

PEDIATRICS ◽  
1978 ◽  
Vol 62 (3) ◽  
pp. 317-321
Author(s):  
Henry Halliday ◽  
Stephen Hirschfeld ◽  
Thomas Riggs ◽  
Jerome Liebman ◽  
Avroy Fanaroff
Keyword(s):  
Right Ventricular ◽  
Preterm Infants ◽  
Systolic Time Intervals ◽  
Left Ventricular ◽  
Ventricular Ejection ◽  
Ejection Time ◽  
Time Intervals ◽  
Normal Term ◽  
Systolic Time ◽  
Ventricular Ejection Time

Right ventricular and left ventricular systolic time intervals (RVSTIs and LVSTIs) were measured in normal term and preterm infants from 1 hour to 90 days of life. LVSTIs in both term and preterm infants were similar in the first five days of life. The ratio of left pre-ejection period (LPEP) to left ventricular ejection time (LVET) was lower in preterm infants older than age 5 days. Estimated gestational age had no influence on LVSTI. The ratio of right preejection period (RPEP) to right ventricular ejection time (RVET) was lower in preterm infants (0.32) than in term newborns (0.37). The preterm RPEP/RVET ratio decreased with age, but at a slower rate than in term babies. This was consistent with the lower pulmonary vascular resistance present in preterm infants.

Value of Systolic Time Intervals in the Diagnosis of Large Patent Ductus Arteriosus in Fluid-Restricted and Mechanically Ventilated Preterm Infants

PEDIATRICS ◽  
1984 ◽  
Vol 74 (6) ◽  
pp. 1069-1074
Author(s):  
François Heitz ◽  
Jean-Claude Fouron ◽  
Nicolaas H. van Doesburg ◽  
Harry Bard ◽  
François Teasdale ◽  
...  
Keyword(s):  
Patent Ductus Arteriosus ◽  
Right Ventricular ◽  
Ductus Arteriosus ◽  
Systolic Time Intervals ◽  
Left Ventricular ◽  
Ejection Time ◽  
Time Intervals ◽  
Systolic Time ◽  
Ventricular Ejection Time ◽  
Patent Ductus

M-mode echocardiographic features suggesting a patent ductus arteriosus are based on two groups of indirect criteria: dilation of the left cardiac cavities and changes of systolic time intervals. The reliability of the first group of criteria has been questioned in fluidlimited, mechanically ventilated preterm infants. The sensitivity of the systolic time intervals in the same circumstances is investigated. Twenty-three patients with a large patent ductus arteriosus were selected. Review of their echocardiograms shows that the sensitivity of the various criteria (expressed as percentage of positivity) was as follows: inversion of the ratio of left ventricular preejection period to right ventricular preejection period, 91.3%; left ventricular preejection period to left ventricular ejection time over right ventricular preejection period to right ventricular ejection time < 1, 83%; left atrium dilation, 74%; shortening of left ventricular preejection period, 70%; dilation of left ventricular internal dimensions in diastole, 65%; increase in left atrium/aorta, 52%; and decrease of left ventricular preejection period to left ventricular ejection time, 48%. Three criteria involving time intervals (left ventricular preejection period to right ventricular preejection period, left ventricular preejection period, and left ventricular preejection period to left ventricular ejection time) had 100% specificity. The lowest specificity was found with criteria involving the left atrium (left atrial to aortic root ratio 75% and left atrium 63%). It is concluded that study of systolic time intervals is a reliable means of detecting preterm infants with hemodynamically significant left-to-right shunt through a patent ductus arteriosus even if the infants are mechanically ventilated and fluid restricted.

Systolic time intervals during +Gz acceleration

1976 ◽  
Vol 41 (1) ◽  
pp. 52-56 ◽  
Author(s):  
T. B. Graboys ◽  
E. D. Michaelson
Keyword(s):  
Recovery Period ◽  
Systolic Time Intervals ◽  
Cardiovascular Function ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Ejection Time ◽  
Time Intervals ◽  
Physiological Variables ◽  
Systolic Time ◽  
Ventricular Ejection Time

Systolic time intervals (STI) were recorded in 8 healthy male volunteersbefore, during, and after 30-s exposures to +3 Gz, +5 Gz, and +7 Gz acceleration. Heart rate (HR) increased at all +Gz levels, as did the HR correctedQSIc interval, left ventricular ejection time (LVETc), preejection period (PEPc) and PEP/LVET. These changes in STI were also proportional to the +Gz level. At the higher +Gz levels, PEPc and PEP/LVET continued to increase early in the recovery period, but HR and all STI returned to control after 60s of recovery. Although physiological variables other than myocardial contractility, such as preload and afterload may influence STI during +Gz the effects of +Gz on stroke volume (SV) and cardiac output (CO) were estimated using previously described relationships between STI and invasively determined indices of cardiovascular function. In general CO increased as SV decreased. During recovery, HR and CO fell and CO remained slightly below controllevels, primarily because estimated SV remained low. This study demonstrates the feasibility of using STI to estimate noninvasively the transient changes in cardiovascular function during +Gz acceleration.

SYSTOLIC TIME INTERVALS (STI) AS INDICATORS OF MYOCARDIAL THYROID HORMONE EFFECT

1978 ◽  
Vol 87 (3) ◽  
pp. 507-515 ◽  
Author(s):  
J. Chakravarty ◽  
A. R. Guansing ◽  
S. Chakravarty ◽  
C. V. Hughes
Keyword(s):  
Thyroid Hormone ◽  
Systolic Time Intervals ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Ejection Time ◽  
Time Intervals ◽  
Left Ventricular Ejection Time ◽  
Hormone Effect ◽  
Systolic Time ◽  
Ventricular Ejection Time

ABSTRACT Systolic time intervals consisting of indices of electromechanical systole (QS2-I), left ventricular ejection time (LVET-I) and pre-ejection period (PEP-I) were calculated serially during therapy in 12 euthyroid, 9 hypothyroid and 9 hyperthyroid individuals. These parameters were analyzed sequentially together with the changes in serum thyroxine (T4), triiodothyronine (T3) and thyrotrophin (TSH) in order to determine the sensitivity of these non-invasive procedures in monitoring peripheral thyroid hormone effect. The results are expreseed in mean ± sem. QS2-I (506.3 ± 8.2 ms) and PEP-I (102.9 ± 4.2) were shortened (P < 0.02 and P < 0.001, respectively) in hyperthyroidism and prolonged (579.3 ± 7.3 and 169.6 ± 3.6 ms) in hypothyroidism (P < 0.01 and P < 0.001, respectively) compared to euthyroid controls (538.1 ± 8.8 and 130.3 ± 5.3 ms), while LVET-I did not change significantly in either condition. Simultaneous determinations of circulating T4, T3 and TSH showed changes appropriate to both hypo- and hyperthyroid states. In 2 patients with T3-thyrotoxicosis, PEP-I was decreased to an average of 103.1 ms, while in 2 patients with compensated hypothyroidism (normal T4 but elevated TSH) this was prolonged to 163.7 ms (average) compared to euthyroid controls. During treatment the hypothyroid group showed significant sequential correlation of TSH and PEP-I. In the hyperthyroid individuals, PEP-I correlated significantly with T4 and T3. PEP-I may be a useful, sensitive, quantitative biologic indicator of thyroid hormone effect on myocardial function.

Reliability of noninvlasive methods for measuring cardiac function in exercise

1978 ◽  
Vol 44 (1) ◽  
pp. 55-58 ◽  
Author(s):  
L. A. Wolfe ◽  
D. A. Cunningham ◽  
G. M. Davis ◽  
P. A. Rechnitzer
Keyword(s):  
Cardiac Output ◽  
Systolic Time Intervals ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Ejection Time ◽  
Time Intervals ◽  
Left Ventricular Ejection Time ◽  
Ejection Rate ◽  
Systolic Time ◽  
Ventricular Ejection Time

Externally recorded systolic time intervals (STI's), indirect (CO2 re-breathing) cardiac output, and auscultatory blood pressures were measured during upright bicycle ergometer work in 20 healthy men, aged 24–56 yr. The subjects were studied on 2 separate days at steady-state work loads chosen to represent light (mean heart rate (HR) = 96 beats.min-1), moderate (HR = 118 beats.min-1) and heavy (HR = 147 beats.min-1) exercise. In addition to determinations of cardiac output, systolic time intervals, and blood pressure, the individual's mean systolic ejection rate (stroke volume/left ventricular ejection time) was calculated as a measure of left ventricular function. In general, heart-rate-corrected STI's were found to be reliable and reproducible. Reliability coefficients for total electromechanical systole and left ventricular ejection time ranged from 0.93 to 0.96 while those for the preejection period and its subcomponents were between 0.63 and 0.88. The reliability of cardiac output, stroke volume, mean systolic ejection rate, and systolic blood pressure was also considered to be acceptable but tended to be higher during moderate and heavy work (r = 0.85–0.95) compared to light exercise (r = 0.60–0.83).

Systolic Time Intervals before and after Maximal Exercise in Adolescents with Insulin-Dependent Diabetes Mellitus

1992 ◽  
Vol 4 (1) ◽  
pp. 85-93 ◽  
Author(s):  
Barbara N. Campaigne ◽  
Kyle W. Landt ◽  
Frederick W. James ◽  
Joan Reimar ◽  
Wayne Mays ◽  
...  
Keyword(s):  
Systolic Time Intervals ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Dependent Diabetes Mellitus ◽  
Ejection Time ◽  
Time Intervals ◽  
Left Ventricular Ejection Time ◽  
Before And After ◽  
Systolic Time ◽  
Ventricular Ejection Time

Systolic time intervals (STI) were measured before and after exercise in 18 diabetic adolescents (D) and 18 age- and sex-matched nondiabetic controls (C). At similar heart rates, pre-exercise pre-ejection period (PEP) and left ventricular ejection time (LVET) were significantly shorter in D compared to C (p<0.05). There was no difference between the two groups in the PEP/LVET ratio. Following exercise there were no differences in STIs between groups. However, the change in PEP and LVET from pre- to postexercise was significantly less in D compared to C (delta PEP 38 vs. 53±3 msec, p<0.01; delta LVET 120 vs. 134±4 msec, p<0.05). These data suggest a hypercontractile state at rest in D and a blunted response to exercise when compared to C. This study provides data that may be relevant to the early identification of individuals at risk for premature diabetic cardiomyopathy.

Physiologic modulations of the systolic time intervals in the fetal lamb

1985 ◽  
Vol 63 (7) ◽  
pp. 893-897
Author(s):  
Xavier De Muylder ◽  
Jean-Claude Fouron ◽  
Harry Bard ◽  
Josée S. Lafond
Keyword(s):  
Cardiac Rhythm ◽  
Respiratory Activity ◽  
Systolic Time Intervals ◽  
Ejection Time ◽  
Time Intervals ◽  
Rr Intervals ◽  
Cardiac Rhythm Variability ◽  
Fetal Lamb ◽  
Systolic Time ◽  
Ovine Fetus

To examine the modulation of fetal systolic time intervals of the ovine fetus in relation to fetal maturation, heart rate, respiratory activity, and circadian rhythm, studies were carried out on 13 fetal–maternal sheep preparations. The data obtained showed that there was a significant correlation between the ejection time (ET) and the RR intervals of the electrocardiogram. The pre-ejection period (PEP) and PEP/ET increased in relation to the fetal maturation (38 ms and 0.25 at 120 days to 52 ms and 0.33 at 145 days of gestation, respectively). When the circadian rhythmicity was analyzed, a relative tachycardia was in evidence during the 21- to 03-h period but systolic time intervals remained unchanged. Except for some tachycardia and cardiac rhythm variability, respiratory activity also had no influence on the systolic time intervals.

Value of Echocardiography in Assessing the Outcome of Bronchopulmonary Dysplasia of the Newborn

PEDIATRICS ◽  
1980 ◽  
Vol 65 (3) ◽  
pp. 529-535 ◽  
Author(s):  
Jean-Claude Fouron ◽  
Jean-Claude Le Guennec ◽  
Didier Villemant ◽  
Harry Bard ◽  
Gilles Perreault ◽  
...  
Keyword(s):  
Bronchopulmonary Dysplasia ◽  
Myocardial Function ◽  
Systolic Time Intervals ◽  
Pulmonary Insufficiency ◽  
X Rays ◽  
Ejection Time ◽  
Time Intervals ◽  
Time Ratio ◽  
Systolic Time ◽  
The Right

Cardiac catheterization of infants with bron-chopulmonary dysplasia has shown right ventricular hypertrophy and pulmonary hypertension in the majority of the survivors. This study was planned to determine whether serial echocardiographic assessments of the pulmonary vascular bed could help to establish short-term prognosis of bronchopulmonary dysplasia and to evaluate myocardial function of the survivors. Ten preterm infants were included in this study. They were classified according to four radiologic stages. A total of 50 echocardiographs were recorded allowing serial measurements of the right systolic time intervals. All infants that eventually expired had a ratio of the preejection period to the ejection time of the right ventricle above 0.3 prior to death (five patients). Infants with normal right preejection period to right ejection time ratio had a good out-come despite persistence of abnormal lung x-rays (four patients). Persistence of O2 dependence with abnormal right systolic time intervals after three months of life eventually led to death (two patients) or serious pulmonary insufficiency (one patient). The lungs as seen on chest x-rays of this patient remained unchanged (moderate stage IV) during six months, while the echocardiograph showed a progressive increase in right preejection period to right ejection time ratio. This infant has now developed cor pulmonale. Myocardial function evaluated on the last echocardiograph of the four infants who were considered cured was within normal limits. In conclusion, indirect assessment of pulmonary pressure by echocardiography can be used for clinical evaluation and ultimate prognosis of bronchopulmonary dysplasia and should be part of the follow-up evaluation of infants suffering from this disease.

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