Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Ejection fraction”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 811 records · Page 45Linked to original sources
PubMedDate not supplied

[Surgical revascularisation of the heart in patients with chronic ischaemic cardiomyopathy and leftventricular ejection fraction of less than 30%].

INTRODUCTION: Patients suffering from chronic ischaemic cardiomyopathy and left ventricular ejection fraction (LVEF) lower than 30% represent a difficult and controversial population for surgical treatment. OBJECTIVE: The aim of this study was to evaluate the effects of surgical treatment on the early and long-term outcome of these patients. METHOD: The patient population comprised 50 patients with LVEF < 30% (78% male, mean age: 58.3 years, range: 42-75 years) who underwent surgical myocardial revascularisation during the period 1995-2000. Patients with left ventricular aneurysms or mitral valve insufficiency were excluded from the study. The following echocardiography parameters were evaluated as possible prognostic indicators: LVEF, fraction of shortening (FS), left ventricular systolic and diastolic diameters (LVEDD, LVESD) and volumes (LVEDV, LVESV), as well as their indexed values (LVESVI). RESULTS: Fifteen patients (30%) died during the follow-up, 2/50 intraoperatively (4%). The presence of diabetes mellitus, previous myocardial infarction, main left coronary artery disease, and three-vessel disease, correlated significantly with the surgical outcomes. The patient's age, family history, smoking habits, hypertension, hyperlipidaemia, history of stroke, peripheral vascular disease, and renal failure, did not correlate with the mortality rate. A comparison of preoperative echocardiography parameters between survivors and non-survivors revealed significantly divergent LVEF, LVEDD, LVESD, LVEDV, LVESV, and LVESVI values. Preoperative LVESVI offered the highest predictive value (R = 0.595). CONCLUSION: Diabetes mellitus, history of myocardial infarction, stenosis of the main branch, and three-vessel disease, significantly affected the perioperative and long-term outcome of surgical revascularisation in patients with ischaemic cardiomyopathy and LVEF < 30%. In survivors, LVEF, FS, and systolic and diastolic echocardiography parameters, as well as their indexed values, significantly improved after surgical revascularisation. LVESVI provided the highest predictive value for mortality.

Adult↗
PubMed1992

Estimation of right ventricular ejection fraction by means of 99Tcm-macroaggregates.

A method is described for assessing right ventricular ejection fraction (RVEF) by means of 99Tcm-macroaggregates (MAA). The method consists of performing, in right anterior oblique (RAO) projection, a direct ECG-gated data acquisition over 120 s, as soon as the intravenous administration of the tracer is started. The activity returning to the left heart being negligible, background is limited to the lung activity overlapping the right ventricle. The distribution of lung activity in the gated frames is, however, exactly the same as that in the lung perfusion image, it can therefore be subtracted using static lung scintigraphy acquired directly after the gated study. Considering the count density distributions in the corrected end-diastolic (ED) and end-systolic (ES) frames and the first harmonic phase and amplitude images, ED and ES RV regions of interest (ROIs) are delineated for the calculation of RVEF. It has been shown that using 5 mCi 99Tcm-MAA, the ED count obtained is similar to that usually observed during a 20 mCi 99Tcm first-pass study. Intraobserver variation is acceptable and there is a good correlation between the RVEF calculated by this method and that obtained by means of a steady-state ECG-gated 81Krm technique. As the method presents similar advantages to those offered by 81Krm while using 99Tcm, it constitutes, in our opinion, a good approach for estimating RVEF in routine clinical practice.

Humans↗
PubMedDate not supplied

Cold infarction areas of varying size in the presence of left ventricular dysfunction: the impact on left ventricular ejection fraction determination by gated SPECT compared to radionuclide ventriculography.

The agreement in left ventricular (LV) ejection fraction (EF) determination between the gated perfusion SPECT (GPS) and radionuclide ventriculography (RVG) methods has been reported to show a systematic reduction with increasing EF values. In some reports, this EF difference exceeds 5%, indicating a critical underestimation rate by GPS in terms of clinical reliability. Although the accuracy of endocardial edge detection by means of GPS proves to be reliable, even in patients with large perfusion defects, the accuracy of EF calculation seems to depend on the level of individual EF values. Our objective was to investigate the RVG-GPS agreement in EF determination specifically in patients with myocardial infarction (MI) having perfusion defects including extremely depleted areas and LV dysfunction. Our patients had a EF<50%, a population in which the best agreement values between the above two methods should be found according to the literature. The idea was to test the accuracy of QGS algorithm in the presence of cold perfusion defects and a low probability of EF level influence. Thirty-six patients (26 males; 61.8+/-9.1 y and 10 female; 64.1+/-10.7 y) with MI older than two weeks, having perfusion defects, including all regions of varying size with no visible tracer uptake in rest GPS and RVG-EF<50% were included in the study. Rest-GPS was performed by injecting iv 925 MBq 99mTc-sestamibi (8-time bins) using a dual-headed gamma camera and rest-RVG was performed within the following three days by injecting iv 740 MBq 99mTc-pertechnetate-pyrophosphate (24 time bins). Myocardial perfusion was visually analyzed on a 17 segment-model and summed rest perfusion scores (SRS) were determined. The cold defect number (CDN) was calculated by selecting the myocardial segments with 0%-9% of maximal tracer uptake (grade 4) to identify the extent of the depleted tissue in each patient. The patients with (3)4 adjacent myocardial segments with grade 4 perfusion were considered as having large cold defects (Group 1: GR1). Patients with two or three CDN constituted the Group 2 (GR2; medium cold defects) and those with only one CDN constituted Group 3 (GR3; small cold defects). Hereafter, the relative weight of cold perfusion defects (CD%) and infarcted segments (IS%) were calculated for all patients and subgroups. Of 36 patients studied, 14 patients (39%, GR1) had large cold defects. Eleven patients (30.5%, GR2) had moderate and 11 (30.5%, GR3) had small cold defects. The overall mean value of CDN was 3.03+/-1.96 (1-9). Mean EF values in RVG and GPS among Groups 1, 2 and 3 were 28.78%+/-6.32%, 38.46%+/-6.43%, 38.73%+/-8.55% and 27.0%+/-6.93%, 37.82%+/-8.80%, 33.27%+/-11.65%, respectively. The percentage of patients showing an EF difference pound 5% between RVG and GPS in Groups 1, 2 and 3 were 93%, 73% and 27%, respectively. The CD% and IS% were 19+/-12, 30+/-7, 14+/-3, 6 and 52+/-20, 61+/-18, 50+/-17, 42+/-23 in overall, GR1, GR2 and GR3, respectively. It is concluded that: the negligible underestimation of EF in GR1 by GPS compared to RVG confirms the stability of the geometric modeling algorithm of QGS in this particular patient sub-group. Although the agreement results in patients with smaller defects were probably influenced through the realization of RVG and GPS studies performed on different days, it seems to be rational to set the threshold of RVG-GPS agreement dependency on EF levels in patients with myocardial infarction lower than 50%.

Female↗
PubMed1989

Comparison of left ventricular ejection fractions determined in healthy anesthetized dogs by echocardiography and gated equilibrium radionuclide ventriculography.

Left ventricular ejection fractions (LVEF) of 8 pentobarbital-anesthetized dogs were calculated by gated equilibrium radionuclide ventriculography (RVG) and by M-mode and two-dimensional echocardiography (2-DE) prior to and during constant IV infusion of isoproterenol. Mean LVEF (+/- SD), determined with RVG by use of an automatic edge detection algorithm (RVG-auto) to define the left ventricular region of interest, increased from a resting value of 53.5% (+/- 4.9%) to 71.9% (+/- 6.8%) during isoproterenol infusion. Mean LVEF, determined with RVG by use of visual inspection (RVG-manual) to define the left ventricular region of interest increased from a resting value of 51.6% +/- 3.8% to 67.0% +/- 5.6% during isoproterenol infusion. Using 2-DE and the bullet formula to calculate left ventricular volume (LVV = 5/6 x cross-sectional area x length), mean LVEF increased from 52.3% (+/- 3.50) to 74.7% (+/- 5.0%). Using 2-DE area measurements and Teicholz formula, mean LVEF increased from 48.9% (+/- 5.1%) to 69.5% (+/- 6.0%). Using M-mode echocardiographic left ventricular diameter measurements and Teicholz formula, mean LVEF increased from 52.3 (+/- 9.0%) to 78.3% (+/- 8.1%). Before and during isoproterenol infusion, the mean LVEF values calculated by RVG agreed closely with mean LVEF values calculated from M-mode and 2-DE. Correlation coefficients determined from linear regression analysis of LVEF by echocardiography vs LVEF by radionuclide ventriculography ranged from 0.79 to 0.88. Correlation coefficients were higher and SEM were lower when LVEF was determined by RVG-manual, rather than by RVG-auto methods and when LVEF was calculated from 2-DE measurements, rather than from M-mode measurements.

Animals↗
PubMed1984

First-pass determination of the right ventricular ejection fraction using two regions of interest and the right anterior oblique view.

The right ventricular ejection fraction (RVEF) was determined on the right anterior oblique view in 9 patients during the first pass of a bolus of technetium-99m employing a gamma camera with high count-rate capability. The RVEF was calculated by using: (i) a fixed end-diastolic region of interest (ROI); and (ii) an end-diastolic and end-systolic ROI. Because of the movement of the tricuspid plane the first of these methods often gave low values, and agreement between the first two peaks was not as good as that when the second method was used. The mean for the second method was in agreement with that in a previous study using a gated first-pass technique and two ROIs but was somewhat higher than those reported by workers using either one ROI or the anterior view.

Cardiac Output↗
PubMed1996

Left ventricular ejection fraction: comparison of results from planar and SPECT gated blood-pool studies.

UNLABELLED: Global ejection fraction (EF) from planar gated blood-pool (GBP) imaging is a widely accepted measure of cardiac function. It has been suggested that planar GBP could be replaced by SPECT. In this article, we compare counts-based global EF measured from SPECT and planar images and investigate reasons for discrepancies between the two. METHODS: Twenty-three subjects were imaged with both planar and SPECT GBP. SPECT short-axis slices were projected to create reprojected images. Reprojected SPECT (rSPECT) images were created in both the true long-axis view and also in a view typical of planar studies (found to be 60 degrees from the true long-axis). Thus, angle of view effects on global EF could be investigated. In addition, we studied the effects of background and attenuation. RESULTS: Long-axis rSPECT EF correlated well with planar EF (r = 0.89) but EF values were significantly higher for rSPECT than for planar (slope = 1.4, intercept = -8 EF units; p < 0.001). We found that background correction may not be necessary with rSPECT, but neither background nor attenuation explained the observed discrepancy between rSPECT and planar EFs. This discrepancy was found to be caused by atrial overlap in the planar image and disappeared when the SPECT slices were reprojected at the same angle of view as the planar images. CONCLUSION: Global EF can be easily measured from rSPECT GBP images. Long-axis rSPECT EFs are, however, greater than planar EFs by a factor of 1.4 because atrial overlap causes a significant drop in planar EF in planar images. These results suggest that (long-axis) rSPECT EFs may be more accurate than planar EFs.

Adult↗
PubMed1990

Impedance cardiography fails to measure accurately left ventricular ejection fraction.

The purpose of this study was to describe the technique proposed to measure left ventricular ejection fraction (LVEF) with the impedance cardiogram and to compare these values with those measured by radionuclide angiocardiography. Characteristics (mean +/- SE) of the healthy control group were: age, 32 +/- 3 yr; weight, 75 +/- 6 kg; and height, 177 +/- 3 cm. Characteristics of the patient population of 46 men and 49 women were: age, 63 +/- 1 yr; weight 74 +/- 2 kg; and height, 170 +/- 1 cm. LVEF was measured by impedance (ZEF) and multiple-gated scans (MEF) while in the supine position. The control group ZEF averaged 72% (range 67% to 78%) and the MEF averaged 71% (range 65% to 77%). There were no differences between the average ZEF (56 +/- 1%) and MEF (53 +/- 2%) in the patients. Correlations, however, between ZEF and MEF were unacceptably low for the several clinical populations within this group (-0.17 to 0.16). Furthermore, MEF correlated well with regional wall motion (r = .84) while ZEF did not (r = .00). Subdividing the patients according to heart function as determined by regional wall motion failed to improve the correlation between MEF and ZEF. The use of a previously published regression equation to predict LVEF from the systolic time interval ratio of pre-ejection period/left ventricular ejection time derived from the impedance cardiogram also proved ineffective. These data suggest that the previously proposed analysis of the impedance cardiogram to measure LVEF should not be used to make a clinical diagnosis.

Adult↗
PubMed2006

The effect of acute hypertension on left ventricular diastolic pressures in a canine model of left ventricular dysfunction with a preserved ejection fraction and elevated left ventricular filling pressures.

BACKGROUND: Decompensated heart failure with preserved left ventricular (LV) ejection fraction (EF) is often accompanied by hypertensive episodes. We hypothesized that acute increase in arterial pressure results in elevated early and late diastolic LV pressures as a result of further impaired LV relaxation. METHODS: To test this hypothesis, we used a chronic canine model of LV systolic dysfunction with preserved LV function (LVDPEF) (EF > 50%) and elevated LV end-diastolic pressure using coronary microsphere embolization. At baseline and with LVDPEF, each dog was paced 10 beats above their baseline heart rate and high-fidelity LV pressures, echocardiographic LV volumes, and transmitral Doppler were obtained before and after methoxamine pressure loading. RESULTS: With normal LV function, LV pressures at peak negative dP/dt (+18 mm Hg, P < .05) and at LV pressure minimum (+3.6 mm Hg, P < .01) increased. Both tau (P < .05) and LV end-diastolic pressure increased (5 +/- 3 vs 13 +/- 4 mm Hg, P < .01). EF was unchanged, although LV end-diastolic volume increased (P < .01). Pressure loading with LVDPEF resulted in a timing delay (P < .05) and a greater increase in LV pressures at peak negative dP/dt (+45 mm Hg) and LV minimal pressure (+7.5 mm Hg) as compared with normal LV function (P < .01). LV end-diastolic pressure increased (9 +/- 2-23 +/- 5 mm Hg, P < .001), diastolic filling period shortened (288 +/- 51-204 +/- 54 milliseconds, P < .01), and tau increased (P < .001). EF declined from 54 +/- 9% to 43 +/- 9% (P < .05) and LV size increased (P < .01). CONCLUSIONS: Pressure loading with normal LV function and with LVDPEF results in increased LV diastolic pressures, which are further exaggerated with LVDPEF as a result of prolonged relaxation and shortened diastolic filling.

Acute Disease↗
PubMed2003

Mitral annulus motion compared with wall motion scoring index in the assessment of left ventricular ejection fraction.

The biplane disc summation method is the recommended echocardiographic procedure to determine left ventricular (LV) ejection fraction (EF). Assessment of mitral annulus motion (MAM) or wall motion scoring index (WMI) has been reported to be less dependent on image quality compared with the recommended method, and proposed as a surrogate to the disc summation method in calculation of LVEF. We aimed to compare MAM and WMI in the echocardiographic assessment of LVEF. In a randomly selected population-based sample of 75-year-old men and women in sinus rhythm (n = 409) MAM, as measured by M-mode, was compared with WMI, calculated as the mean value of wall motion scoring in 9 LV segments. LVEF, as measured by the biplane disc summation method was used as reference. The limits of agreement (mean difference +/- 1.96 SD) between LVEF and corresponding MAM values were -18 to +13 LVEF%, and between LVEF and corresponding WMI values were -12 to +13 LVEF%. The areas under the receiver operating characteristic curves for MAM and WMI to predict a LVEF < 50% were 0.892 and 0.998, respectively (95% confidence interval of the difference 0.062-0.149). The corresponding areas for MAM and WMI to predict a LVEF < 40% were 0.955 and 0.998, respectively (95% confidence interval of the difference 0.017-0.069). In conclusion, the ability of WMI to estimate LVEF was more favorable than MAM in this population-based sample of 75-year-old participants. The findings suggest that the WMI is preferable to MAM in estimating LVEF.

Aged↗
PubMed2003

Age, but not sex, influences the measurement of ejection fraction in elderly patients hospitalized for heart failure.

BACKGROUND: Current US and European guidelines recommend that ejection fraction (EF) be measured at least once in patients with congestive heart failure (CHF). However, it is not known how age and sex influence adherence to this recommendation. METHODS: We reviewed a national sample of Medicare patients discharged with a principal diagnosis of heart failure and sought to determine the frequency of measurement of EF and the frequency of preserved systolic function (EF > 40%) by age and sex. RESULTS: A total of 2,239 patients were included in this study. EF was known or measured in 59.2% of all admissions. EF was measured less often in women and with increasing age, but using logistic regression only increasing age (P <.0001) and not sex (P =.247) was associated with a lower frequency of EF measurement. Women were more likely than men to have preserved systolic function in all age groups older than age 65 (P <.001), but the frequency of preserved systolic function increased with age in both men and women. CONCLUSIONS: In Medicare patients discharged with a principal diagnosis of heart failure, only 59% have a measurement of EF. Women have EF measured less often than men; this is solely a function of the older age of women. Preserved systolic function increases in both men and women with CHF with increasing age, but women are far more likely than men to have preserved systolic function at all ages.

Age Factors↗
PubMed2001

Contrast-enhanced quantitation of left ventricular ejection fraction: what is the best method?

The need to enhance the echocardiographic determination of left ventricular ejection fraction (LVEF) is greatest in patients with suboptimal images. We have previously demonstrated that in difficult-to-image patients, contrast-enhanced power harmonic imaging resulted in accurate calculation of LVEF by using Simpson's method. However, the incremental accuracy of contrast enhancement with other methods of determining LVEF has not been examined. This study prospectively assessed the comparative accuracy of LVEF determination by using the Quinones' method with fundamental imaging (FU), tissue harmonic imaging (TH), contrast-enhanced harmonic imaging [TH(CON)], as well as Quinones' method with contrast-enhanced power harmonic imaging [POW(QUIN)] in 62 patients with suboptimal images. LVEF was also calculated by using contrast-enhanced power harmonic imaging and Simpson's method [POW(SIMP)] in these patients. We demonstrated that LVEF calculated from the POW(QUIN) mode had the best agreement with radionuclide angiography (standard of comparison) compared with FU, TH, and TH(CON). However, POW(SIMP) was even more accurate. In conclusion, when the Quinones' method was used to calculate LVEF in difficult-to-image patients, POW(QUIN) mode was the most accurate. However, POW(SIMP) was even more accurate and should be the method of choice when a high degree of quantitative accuracy is required.

Adult↗
PubMed1999

Prognostication in 3-vessel coronary artery disease based on left ventricular ejection fraction during exercise : influence of coronary artery bypass grafting.

BACKGROUND: Previous data indicate that left ventricular ejection fraction (LVEF) provides prognostic information among patients with coronary artery disease (CAD), but the value of such testing specifically for defining benefits of coronary artery bypass grafting (CABG) may relate to severity of exercise-inducible ischemia measured noninvasively before surgery. METHODS AND RESULTS: To determine the independent prognostic importance of preoperative ischemia severity for predicting outcomes of CABG among patients with extensive CAD, we monitored 167 stable patients with angiographically documented 3-vessel CAD (average follow-up of 9 years in event-free patients) who previously had undergone rest and exercise radionuclide cineangiography. Their course was correlated with data obtained during initial radionuclide testing, coronary arteriography, and clinical evaluation at study entry. Fifty-two patients received medical treatment only, and 115 underwent CABG (44 early [</=1 month after initial study]). Multivariate Cox model analysis indicated that change (Delta) in LVEF from rest to exercise during radionuclide study was the strongest independent predictor of major cardiac events (P=0.003) before surgery and also predicted magnitude of CABG benefit (P=0.04). Patients with DeltaLVEF -8% or less derived significant survival-prolonging and event-reducing benefit from CABG performed </=1 month after initial testing (P<0.02 for cardiac death and P=0.008 for cardiac events], early CABG versus medical-treatment-only patients); similar benefits were absent among patients with DeltaLVEF more than -8%, and among those in whom CABG was deferred. CONCLUSIONS: Assessment of ischemia severity based on LVEF response to exercise enables effective prognostication among patients with 3-vessel CAD and defines the likelihood of life-prolonging and event-reducing benefits from CABG.

Aged↗
PubMed1983

Serial changes in left ventricular ejection fraction in the early hours after aortocoronary bypass grafting.

To determine the course of left ventricular ejection fraction (LVEF) in the early hours after aortocoronary bypass grafting, 24 patients underwent serial gated bloodpool scanning. Twenty-two had received propranolol until the day of surgery. ECGs showed no evidence of perioperative infarction. Preoperatively, the mean (+/- SD) LVEF was 0.56 +/- 0.13; after bypass, it was 0.38 +/- 0.11 at 4 hours, 0.42 +/- 0.12 at 5 hours, 0.43 +/- 0.11 at 6 hours, 0.48 +/- 0.13 at 7 hours, 0.52 +/- 0.15 at 8 hours, and 0.54 +/- 0.15 at 10 to 14 days. The LVEFs at 4, 5, and 6 hours postoperatively were significantly lower than preoperatively (p less than 0.05). Postoperative mean heart rate was higher at all times; mean temperature was depressed at 4 and 5 hours and elevated at 7 and 8 hours; and mean arterial blood pressure was depressed at 7 hours, 8 hours, and 10 to 14 days (p less than 0.05). The degree of the early postoperative LVEF depression correlated with the daily preoperative propranolol dose (p less than 0.05) and was unrelated to bypass time, aortic cross-clamp time, or changes in temperature, heart rate, and blood pressure. The LVEF at 10 to 14 days postoperatively was not significantly different from the preoperative value. The LVEF is depressed in the early hours after aortocoronary bypass grafting and approaches the preoperative value with time. The magnitude of the early depression appears to be related to the preoperative propranolol dose, but does not significantly correlate with factors related to surgical technique.

Adult↗
PubMed1977

[Prognosis for coronary patients with low ejection fraction. Comparison between a medically and a surgically treated group].

Two groups of coronary patients whose ejection fraction was depressed (less than or equal to 0.30) were studied. Twelve patients received drug treatment only and 25 others underwent surgery. Life expectancy appears to be slightly improved in the surgical group, but the differences are not statistically significant. Since operative mortality is relatively low (8%) and clinical improvement following surgery may be impressive, a revascularization procedure should be considered even in patients with markedly impaired ventricular function.

Coronary Disease↗
PubMed1983

Determination of right ventricular ejection fraction utilising a radionuclide washout technique.

A radionuclide washout technique (WO), for calculation of the right ventricular ejection fraction (RVEF) which is independent of the exact position of the right ventricular region of interest was evaluated and results compared with first pass (FP) and equilibrium gated blood pool (GBP) values. Regression analysis between RVEF values of 24 patients obtained from FP and WO yielded a correlation coefficient (r) of 0.89, while a slightly poorer correlation coefficient was obtained when FP and GBP were compared (r = 0.79) and between WO and GBP (r = 0.71). No significant difference between RVEF values calculated from the three techniques was found (P less than 0.05) on inter- and intraobserver level. The radionuclide washout technique yields an accurate determination of RVEF without the necessity of outlining the RV accurately.

Adult↗
PubMed2007

Hypotension induced by lateral decubitus or supine spinal anaesthesia in elderly with low ejection fraction undergone hip surgery.

OBJECTIVE: The aim of the study was to assess the effect of low ejection fraction (EF) on hypotension during lateral or supine position of spinal anaesthesia in patients older than 75 years old. METHODS: We analyzed 41 patients who had undergone hip surgery between August 2000 and October 2001 in the Aydin SSK State Hospital retrospectively. Patients older than 75 years of age and an EF less than 50% were selected and spinal anaesthesia was performed with hyperbaric bupivacaine 0.5%, lateral decubitus or supine position. The patients were divided into two groups: Group I (unilateral group, n = 23) and Group II (supine group, n = 18). History of hypertension, diabetes mellitus, and ASA status, preoperative value of EF and cardiac index, and intraoperative hypotension, bradycardia, ephedrine use, and maximal sensorial block levels were recorded. RESULTS: The age range of patients was between 75 and 103. The maximal sensorial block level was evaluated due to lower or higher than thoracic sixth segment for each patient in intraoperative period. The sensorial block level higher than thoracic sixth segment were determined 2 patient in Group I and 14 patients in Group II (p = 0.001). Hypotension was observed in five patients in Group I and 10 patients in Group II (p = 0.015). In Group I, the number of ephedrine used patient was lower than Group II (p = 0.015). CONCLUSIONS: Elderly patients with low EF were more likely to predispose to higher sensorial block level and hypotension was more common during spinal anaesthesia with supine position compared to lateral decubitus position.

Aged↗
PubMed1984

Effects of heart rate changes on left ventricular volume and ejection fraction: a 2-dimensional echocardiographic study.

The influence of heart rate on left ventricular (LV) volumes and ejection fraction (EF) using 2-dimensional (2-D) echocardiography during atrial pacing was analyzed. The study was performed in 13 normal control subjects, 23 patients with coronary heart disease and 8 patients with dilated cardiomyopathy. An electronic sector scanner (2.25 MHz, 84 degrees) was used. Under constant scanning of the left ventricle, heart rate was increased, in steps of 20 beats/min, from 80 to 140 beats/min. The 2-D echocardiograms were stored on videotape and analyzed off-line. The end-diastolic and end-systolic volumes (EDV and ESV) were determined using a disc method. Stroke volume (SV) and EF were calculated. Constant LV scanning was possible during atrial stimulation, as shown by the analysis of simultaneously recorded 2-D echocardiograms and cineventriculograms at different heart rates, revealing a constant position of the echocardiographic transducer. Simultaneous recordings of cineventriculography and 2-D echocardiography at 80 and 120 beats/min showed that despite differences in absolute values, percent changes of LV volumes and EF determined with both methods were similar. Thus, changes of LV function can be analyzed by 2-D echocardiography. In normal control subjects, an increase in heart rate of 10 beats/min reduced EDV by 4 ml, ESV by 2 ml, SV by 2 ml and EF by 1%, corresponding to percent reductions of 4, 2, 5 and -2%, respectively. In contrast, the absolute decreases in the patients were 6 ml, 1 ml, 5 ml and 2% and the percent changes 2%, 1%, 8% and 5%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Estimation of left ventricular myocardial function by the ejection fraction in isolated, chronic, pure aortic regurgitation.

In patients with aortic regurgitation (AR), the left ventricular (LV) ejection fraction (EF) may not adequately reflect depressions of myocardial contractility due to decreased aortic impedance. The sensitivity of end-systolic pressure-volume relations and stress-volume relations in detecting myocardial depression in patients with AR was studied. In 12 patients with normal valvular function but with varying LV function (due to coronary heart disease in 9 patients and dilated cardiomyopathy in 3 patients) (group 1), and in 8 patients with AR (group 2), LV angiography was performed before and after sublingual application of isosorbide dinitrate. Heart rate was kept constant by right atrial pacing. In group 1, the slope k of the end-systolic pressure-volume relation was to EF at rest: k = 0.091.e0.051 EF; r = 0.88. In AR, this relation was shifted significantly to the right: k = 0.019.e0.066 EF; r = 0.92. This shift persisted when the end-systolic stress-volume relation instead of the end-systolic pressure-volume relation was calculated. Thus, in patients with AR the end-systolic pressure-volume relation is flatter than that in patients with intact valvular function at a given EF. The same is true for the end-systolic stress-volume relation. The data indicate that EF overestimates myocardial contractility in AR compared with end-systolic pressure-volume or stress-volume relations. This overestimation is probably a result of decreased aortic impedance in AR.

Adult↗