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At least 19 recordsLinked to original sources
PubMed1977

[Reference values of cardiac volume in children and adults of the Ivory Coast].

The cardiac volume in decubitus was measured by Rohrer radiological method in 229 subjects, of which 150 were children of both sexes, aged 4 to 16 and 79 were adult males, 17 to 50 years old. Anthropometric parameters and maximum O2 consumption were also measured. Considering that the size of thorax in Ivory Coast natives is significantly smaller than that of a Caucasian, an eventual influence over the cardiac volume was looked for. Results showed that: -- in the child, the cardiac, volume increased linearly with age: 162 ml at 4 and 680 ml at 16; -- significant positive correlations were found between the cardiac volume, the body-weight andusrface, and the measurements of the thorax; -- when compared to data found in the literature, the cardiac volumes of children and adults of the Ivory Coast in relation with the body weight or surface are lower than the values found in Caucasians; -- children who have been swimming for two years and adults from the national swimming team have a cardiac volume significantly superior to that of Ivory controls; for these subjects, results are equivalent to those of Caucasians; -- there is a highly significant positive correlation between the cardiac volume and the maximum oxygen consumption. To compare values of cardiac volume in different populations, it is necessary that the groups of subjects be very homogeneous and have a comparable level of activity.

Adolescent↗
PubMed1976

[Reproductibility of the true measurement of blood volume, cardiac output, mean pulmonary circulation time and pulmonary blood volume by radiocardiography].

Radiocardiography provides a simple method of measurement of blood volume, cardiac output, mean pulmonary circulation time, and pulmonary blood volume. The use of a computer allows the results to produced immediately provided that the circulating blood volume is measured during the test anpd that the radiocardiographic tracing is analysed by an entirely automatic method. The reproducibity of the results given by this automatic method has been studied in 35 patients, two measurements being made at 20 minute intervals. The standard deviation of the percentage difference between consecutive measurements was 5.8% for the blood volume, 10.4% for the cardiac output, 8.8% for the mean pulmonary circulation time, and 9.7% for the pulmonary blood volume.

Adolescent↗
PubMedDate not supplied

Cardiac volume measurement errors.

Measurements of cardiac volumes based on biplane radiographic data exhibit a cyclical variation as the heart is rotated with respect to the radiologic instrumentation. This study develops a theoretical basis for evaluating the measurement errors due to orientation, that explains the cyclical variation. Since this type of measurement error is always one of overestimation, better accuracy will be obtained if several views are performed at varying orientations and the smallest of the resulting values is used as the measurement.

Animals↗
PubMed1992

Hemodynamic and plasma atrial natriuretic factor responses to cardiac volume loading in young versus older normotensive humans.

To assess the effects of age on responsiveness of atrial natriuretic factor (ANF) release, and the possible contribution of cardiac sympathetic activity, in young (n = 8) and older normotensives (n = 7), the effects of cardiac volume load on plasma ANF, central venous pressure, and general hemodynamics were evaluated. Studies were performed after pretreatment with placebo or 80 mg propranolol. Cardiac volume loading increased central venous pressure by 3-5 mmHg (1 mmHg = 133.3 Pa); beta-blockade did not affect this response. Cardiac volume load caused significant increases in heart rate (10-15 beats/min) and cardiac index (by 0.7-0.8 L.min-1.m-2) and decreases in plasma catecholamines. Propranolol attenuated the increases in heart rate and cardiac index. These hemodynamic responses did not differ significantly between the two groups of subjects. Cardiac volume load significantly increased plasma ANF, by 87 +/- 21 pg/mL in the young normotensives and by 212 +/- 33 pg/mL in the older normotensives (p < 0.01, young vs. older). beta-Blockade did not affect this different response. Our results show that the plasma ANF response to volume loading is potentiated by aging. Although differences in atrial stretch cannot be excluded, this effect may relate to the decrease in clearance of plasma ANF occurring with aging.

Adult↗
PubMed1992

Factors influencing serial measurements of cardiac volumes by count-based methods: effects of elevated catecholamines, position, and exercise on technetium-99m-blood radioactivity concentration.

Most radionuclide methods for measuring cardiac volume require a determination of the blood radioactivity concentration. Thus, changes in blood radioactivity over time or during interventions might lead to spurious volume estimates unless blood radioactivity is serially measured. The effects of elevated epinephrine, posture and exercise on 99mTc-labeled blood radioactivity concentration were studied in 15 young (mean age = 28 yr) and 14 older (mean age = 68 yr) healthy males. An epinephrine infusion of 50 ng/kg/min resulted in a 4.1% +/- 1.0% increase in 99mTc-blood radioactivity (p less than or equal to 0.001) compared to baseline. Sitting increased blood radioactivity concentration by 12.3% +/- 3.0% (p less than 0.0002) compared to the supine position and peak supine bicycle exercise caused an 11.0% +/- 1.7% increase (p less than or equal to 0.0001) compared to supine rest. There was a significantly greater increase during peak supine exercise in the young compared to the older subjects (15.0% +/- 2.3% versus 6.3% +/- 2.0%, p less than or equal to 0.01). The mechanism of the increase in blood radioactivity concentration is uncertain, but presumably reflects the addition of hemoconcentrated red blood cells from the spleen and/or the loss of plasma volume. Failure to correct for the increased blood radioactivity concentration during exercise or pharmacological interventions will result in a significant error in serial measurements of cardiac volumes by methods requiring RBC radioactivity measurements.

Adult↗
PubMed1991

Atrial natriuretic factor, cardiac volumes and filling pressures during exercise in congestive heart failure.

To study the mechanism of atrial natriuretic factor (ANF) release in heart failure, we measured plasma ANF concentrations, cardiac volumes and filling pressures at rest and during three graded exercise levels (E1, E2, E3) in six male patients with congestive heart failure (CHF) and compared them with 13 normal male subjects. At rest, ANF concentrations were sixfold higher in patients with CHF than in normal subjects (at rest: 53 +/- 12 vs 8 +/- 1 pmol.l-1; P less than 0.02). End-systolic ventricular volumes were increased threefold in patients with CHF (P less than 0.02) despite normal mean central venous pressure, pulmonary artery pressure (PAP) and pulmonary wedge pressure (PWP). A positive correlation was found between end-systolic ventricular volumes and plasma ANF (r = 0.93, P less than 0.001). During exercise, ANF rose by 120% over basal values both in patients with CHF and in normal subjects (P less than 0.01). Volumes higher than normal in patients with CHF increased further at E2 (P less than 0.05) in contrast to a decrease of systolic volumes recorded in normal subjects (P less than 0.05). Filling pressures rising abnormally in patients with CHF correlated with plasma ANF during exercise (r = 0.53, P less than 0.02 for PAP; r = 0.51, P less than 0.05 for PWP). In conclusion, our data suggest that ANF release in CHF is regulated at rest by cardiac volumes when filling pressures are still normal. During exercise, ANF release is not impaired in CHF with normal rest filling pressures and is regulated during exercise by left filling pressures.

Aged↗
PubMed1992

Radionuclide cardiac volumes: effects of region of interest selection and correction for Compton scatter using a buildup factor.

The effects of region of interest (ROI) selection and correction for Compton-scattered photons using a buildup factor on radionuclide left ventricular volumes calculated by the Links method were compared in 19 humans with contrast ventriculography and in phantoms. Three different methods of ROI selection were compared: a manual ROI, a second derivative ROI and a 50% count-threshold ROI. In phantoms without Compton scatter correction, volumes were overestimated by 30% (manual ROI), 20% (derivative ROI) and 1% (count threshold ROI). In subjects, results without Compton scatter correction were similar with overestimates of 50% (manual ROI) and 20% (derivative ROI) and an underestimate by 3% (count threshold method). Correction for Compton-scattered photons with the use of a phantom-derived buildup factor resulted in improved accuracy for the manual ROI (+15%) and the derivative ROI (0%). A 50% count threshold ROI following interpolative background subtraction allows the accurate calculation of cardiac volumes without the need for scatter correction, while a second derivative ROI method requires a correction for Compton scatter with the use of a buildup factor.

Cardiac Volume↗
PubMed1991

Effects of posture, Valsalva maneuver and respiration on atrial flutter rate: an effect mediated through cardiac volume.

The effects of passive upright tilting from 0 degrees to +60 degrees (n = 27), Valsalva maneuver (n = 16) and respiration (n = 10) on the rate of atrial flutter were studied in 27 patients. After tilting to +60 degrees, the atrial flutter cycle length shortened in all patients from 247.5 +/- 7 to 236.7 +/- 6.9 ms (range of shortening 1 to 21 ms, p less than 0.001). The Valsalva maneuver (strain of 40 mm Hg) shortened the flutter cycle length during the strain (phase 2) from 242.2 +/- 4.6 to 230.5 +/- 5 ms (range of shortening 2 to 19 ms, p less than 0.001). In 10 patients whose respiration was monitored, the flutter cycle length consistently prolonged during inspiration and shortened during expiration. Combined beta-adrenergic and muscarinic receptor blockade in six patients did not significantly alter the flutter cycle length at rest or the effects of the various maneuvers on the changes in flutter cycle length. This study revealed that the atrial flutter cycle length can be shortened by passive upright tilting, the strain phase of the Valsalva maneuver and expiration. Changes in flutter cycle length were independent of autonomic tone, implying that by decreasing cardiac volume, these maneuvers affect characteristics of the atrial flutter circuit, thereby producing dynamic changes in the rate of atrial flutter.

Atrial Flutter↗
PubMed1975

[Usability of methods for the determination of minute cardiac volume under clinical conditions].

Methods for determination of cardiac output are described and their evaluation and possibilities to use them in clinical practice mentioned. Out of the invasive methods apart from the classical Fick's method, the dye dilution method is of advantage during catheterization, being relatively simple and ready to be easily repeated if necessary directly at the bed side. The common disadvantage of all invasive methods is the disturbance of the patient's basal state. Noninvasive methods yield results suitable more or less for orientation only. From these techniques the indirect method of Fick using the rebreathing of CO2 is simple and can be applied at the bed side. So called physical methods are already obsolete at present.

Cardiac Catheterization↗
PubMed1975

[Method of continuous monitoring of stroke and minute cardiac volume by the aortic pressure curve].

A new method of determining the cardiac output and stroke volume on the basis of the aortic pressure curve by way of a direct pressure-volume calibration is suggested. For this purpose two catheters are introduced into the ascending aorta, and via one of them saline is supplied with a constant volume rate (delta V). At the same time the augmentation of the diastolic pressure in the aorta (delta P) caused by the administration of the saline is recorded by means of the second catheter which tip is located some 3--4 cm below the first one along the blood flow. The mean pulse pressure in the aorta (Pp) also corresponds to a definite flow in the aorta (V). The relationship between the volume and pressure in the aorta within the physiological range is a lineal function. Hence, V = Pp-delta V divided by delta P cm3/sec. By multiplying this value times the duration of the cardiac cycle in seconds, the stroke volume is obtained. By dividing the volume of the administered saline (delta V.t) into the pressure augmentation area (delta S), the volume corresponding to each unit of the pressure area is found. Then by multiplying this calibration value times the area under the pressure curve in any cardiac cycle (S) again the stroke volume is obtained: Vstr = S-deltaV-t divided by delta S cm3. By a continuous recording of the mean pulse pressure in the aorta and of the full pressure curve it is possible to conduct a continuous control of the stroke volume and cardiac output using the preliminarily obtained calibration value. The suggested method permits to determine the filling of the aorta below the coarctation, the blood return from the aorta into the left ventricle in cases of aortic insufficiency, as well as the elastic properties of the aorta. An attempt was made to substitute the recording of the volume pulse and left arm rheopletysmography for the recording catheter.

Aorta↗
PubMed1975

[A modification of the Roher-Kahlstorf method for estimating rapid changes in cardiac volume].

A simple roentgenological procedure is described, by which it is possible to measure the heart volume and its alteration during early orthostatic adaptation.--Long distance films are taken in the p.a.-projection using a 70-mm-camera with a frequency of 2 to 4 exposures per second. The length and width and there by the plane of the heart are determined from these films. The mean horizontal depth diameter, that is necessary to calculate the volume of the heart can be gained by indirect means. There is no statistically significant difference between the heart volumes, that have been determined in 12 test persons by the method described, and the commonly used method. -- The alteration of the heart volume in 10 test persons were investigated during acute orthostatic stress. The heart volume, which was 693 +/- 24,8 ml before the orthostatic stress, decreased within 6,9 +/- 1,6 sec statistically significant by 16,5% An influence of the movements of the diaphragm on the heart volume determination could be excluded.

Angiocardiography↗