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Assessment of vasodilator therapy in patients with severe congestive heart failure: limitations of measurements of left ventricular ejection fraction and volumes.

Although noninvasive techniques are often used to assess the effect of vasodilator therapy in patients with congestive heart failure, it is unknown whether changes in noninvasively determined left ventricular ejection fraction, volume, or dimension reliably reflect alterations in intracardiac pressure and flow. Accordingly, we compared the acute effect of sodium nitroprusside on left ventricular volume and ejection fraction (determined scintigraphically) with its effect on intracardiac pressure and forward cardiac index (determined by thermodilution) in 12 patients with severe, chronic congestive heart failure and a markedly dilated left ventricle. Nitroprusside (infused at 1.3 +/- 1.1 [mean +/- standard deviation] microgram/kg/min) caused a decrease in mean systemic arterial, mean pulmonary arterial, and mean pulmonary capillary wedge pressure as well as a concomitant increase in forward cardiac index. Simultaneously, left ventricular end-diastolic and end-systolic volume indexes decreased, but the scintigraphically determined cardiac index did not change significantly. Left ventricular ejection fraction averaged 0.19 +/- 0.05 before nitroprusside administration and increased by less than 0.05 units in response to nitroprusside in 11 of 12 patients. The only significant correlation between scintigraphically and invasively determined variables was that between the percent change in end-diastolic volume index and the percent change in pulmonary capillary wedge pressure (r = 0.68, p = 0.01). Although nitroprusside produced changes in scintigraphically determined left ventricular ejection fraction, end-systolic volume index, and cardiac index, these alterations bore no predictable relation to changes in intracardiac pressure, forward cardiac index, or vascular resistance. Furthermore, nitroprusside produced a considerably greater percent change in the invasively measured variables than in the scintigraphically determined ones.

Blood Pressure↗

The value of ejection fraction as a predictor of early and late survival following aortocoronary bypass surgery in patients with moderate to severe depression of the left ventricular function.

Predictability analysis of early and late survival of coronary bypass patients with reduced left ventricular function was performed using stepwise logistic regression based on preoperative and operative data. The total perioperative mortality was 3.4% and the total actuarial survival of the whole group at 42 months was 87.7%. Thirty preoperative and operative parameters of 149 patients were entered into a first mathematical model. Four parameters were selected as a consequence: ejection fraction, anginal class, obesity, septal infarct. A prediction model based on these parameters, gave a correct prediction of the operative outcome in 99.3% of the patients. However due to the only five perioperative deaths, this model should be interpreted with caution. The accuracy of ejection fraction alone was 97.3%, the sensitivity was 100% but the specificity was only 20%. The same parameters of 97 patients were entered into a second mathematical model. Four parameters were selected in this case: ejection fraction, NYHA functional classification, septal infarct, anterior infarct. A second prediction model, based on these parameters, gave a correct prediction of the late outcome at 24 months in 93.8% of the patients. The accuracy of the discrimination on the basis of ejection fraction alone was 89.7%, its sensitivity was 96.5% but its specificity was only 41.7%. Ejection fraction was the best predictor out of the studied variables but due to its low specificity not good enough as a sole parameter.

Adult↗

Computer modeling of planar myocardial perfusion imaging: effect of heart rate and ejection fraction on wall thickness and chamber size.

Myocardial perfusion imaging is generally performed as a static acquisition without regard for dynamic changes in the cardiac cycle. The effect of heart rate and ejection fraction on the appearance of left ventricular chamber size and wall thickness as perceived in 201Tl scintigrams has not, to our knowledge, been previously studied. A dynamic computer model of the left ventricle was constructed, capable of varying the heart rate and ejection fraction. Parallel slices through the model were convolved with experimentally derived 201Tl point spread functions at corresponding depths to incorporate the effects of scatter and attenuation. Both gated and static left anterior oblique images were created at three clinically encountered heart rates and ejection fractions, with constant end-diastolic volume and left ventricular mass. Results of the study indicate that perceived and quantified wall thickness increases and chamber size decreases appreciably with increasing ejection fraction and (slightly) with increasing heart rate. Thus, evaluation of wall thickness and chamber size in planar images should take into account variations in heart rate and contractility. This is especially pertinent to estimates of left ventricular hypertrophy and chamber size, attempted from nongated myocardial perfusion images.

Computers↗

Ventricular ejection fractions of linear transformation and ellipsoid models.

Eigenvolumes calculated from a linear transformation model were found previously to be linearly related to balloon volumes in excised hearts. The present study analyzed endocardial marker kinematics in intact, contracting left ventricles by biplane cinefluorography. Ejection fractions of the linear transformation model were compared by linear regression analysis with those of an ellipsoidal model, whose ejection fractions had been documented previously in closed and open-chest dog preparations. Data from 10 dogs indicated a correlation coefficient of 0.98 and a regression equation with close similarity to the line of identity. Ejection fractions calculated from the linear transformation model are concluded to be proportional to actual ejection fractions in intact, beating left ventricles.

Algorithms↗

Ejection fraction response to supine exercise in asymptomatic aortic regurgitation: relation to simultaneous hemodynamic measurements.

The change in ejection fraction during exercise is frequently employed as a measure of left ventricular functional reserve in patients with aortic regurgitation. However, little information is available about its relation to invasive measurements of cardiac performance. Therefore, simultaneous hemodynamic measurements and supine exercise blood pool scintigraphy were performed in 14 patients with severe, asymptomatic or minimally symptomatic aortic regurgitation associated with cardiomegaly but preserved left ventricular function at rest. Their hemodynamic measurements at rest were normal and their exercise capacity was excellent. When the patients were categorized into those patients whose ejection fraction increased or did not decrease by more than 0.05 (Group 1) and those whose ejection fraction decreased by more than 0.05 (Group 2), important differences were apparent. Echocardiographic, radionuclide and hemodynamic measurements at rest in the two patient groups were similar, but Group 1 exhibited a greater increase in cardiac index during supine exercise (2.8 +/- 0.4 to 10.0 +/- 1.8 versus 2.7 +/- 0.5 to 6.9 +/- 1.0 liters/min per m2; p less than 0.005) and a lesser increase in pulmonary capillary wedge pressure (13 +/- 4 to 19 +/- 7 versus 12 +/- 4 to 31 +/- 8 mm Hg; p less than 0.01). The severity of regurgitation decreased during exercise in all patients, but end-diastolic volume decreased and end-systolic volume decreased or was unchanged in Group 1, whereas end-diastolic volume was unchanged and end-systolic volume increased in Group 2.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Estimation of left ventricular filling pressures using two-dimensional and Doppler echocardiography in adult patients with cardiac disease. Additional value of analyzing left atrial size, left atrial ejection fraction and the difference in duration of pulmonary venous and mitral flow velocity at atrial contraction.

OBJECTIVES: The purpose of this study was to determine whether left atrial size and ejection fraction are related to left ventricular filling pressures in patients with coronary artery disease. BACKGROUND: In patients with coronary artery disease, left ventricular filling pressures can be estimated by using Doppler mitral and pulmonary venous flow velocity variables. However, because these flow velocities are age dependent, additional variables that indicate elevated left ventricular filling pressures are needed to increase diagnostic accuracy. METHODS: Echocardiographic left atrial and Doppler mitral and pulmonary venous flow velocity variables were correlated with left ventricular filling pressures in 70 patients undergoing cardiac catheterization. RESULTS: Left atrial size and volumes were larger and left atrial ejection fractions were lower in patients with elevated left ventricular filling pressures. Mean pulmonary wedge pressure was related to mitral E/A wave velocity ratio (r = 0.72), left atrial minimal volume (r = 0.70), left atrial ejection fraction (r = -0.66) and atrial filling fraction (r = -0.66). Left ventricular end-diastolic and A wave pressures were related to the difference in pulmonary venous and mitral A wave duration (both r = 0.77). By stepwise multilinear regression analysis, the ratio of mitral E to A wave velocity was the most important determinant of pulmonary wedge (r = 0.63) and left ventricular pre-A wave (r = 0.75) pressures, whereas the difference in pulmonary venous and mitral A wave duration was the most important variable for both left ventricular A wave (r = 0.75) and left ventricular end-diastolic (r = 0.80) pressures. The sensitivity of a left atrial minimal volume > 40 cm3 for identifying a mean pulmonary wedge pressure > 12 mm Hg was 82%, with a specificity of 98%. CONCLUSIONS: Left atrial size, left atrial ejection fraction and the difference between mitral and pulmonary venous flow duration at atrial contraction are independent determinants of left ventricular filling pressures in patients with coronary artery disease. The additive value of left atrial size and Doppler variables in estimating filling pressures and the possibility that left atrial size may be less age dependent than other mitral and pulmonary venous flow velocity variables merit further investigation.

Atrial Function, Left↗

[Improved left ventricular ejection fraction directly after transluminal coronary angioplasty].

The purpose of this study was to evaluate if left ventricular ejection fraction (EF) at rest can improve already during the first 4 h after successful transluminal coronary angioplasty (PTCA). Measurements were carried out with the CardioScint LV Function Monitor Version 1.3. Comparison of ejection fraction values evaluated by the CardioScint Monitor revealed a good correlation with usual equilibrium radionuclide ventriculography (n = 28; r = 0.89). Also, intra- and interobserver variability was low (n = 26; r = 0.94 and n = 21; r = 0.92 respectively). Two hundred follow-up-measurements in eight patients over a time period of 4 h revealed a significant decrease of EF from 45 +/- 12% to 39 +/- 18% (p = 0.037) (reference group). This decrease was due to a continuous increase of background activity. The study population consisted of 14 patients with successful PTCA (dilatation from 85 +/- 7 to 34 +/- 9% linear vessel diameter). To evaluate the hemodynamic significance of the coronary lesion, left ventricular ejection fraction was registered during the balloon occlusion of the vessel. After dilatation, 25 EF measurements were carried out in each patient over the following 4 h (350 values). During PTCA, EF decreased from 52 +/- 16 to 37 +/- 9% (p = 0.0027). During the 4-h follow-up EF slightly decreased from 50 +/- 8 to 46 +/- 9% (p = 0.07).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Left ventricular ejection fraction in children measured by three-dimensional echocardiography using a new transthoracic integrated 3D-probe. A comparison with equilibrium radionuclide angiography.

BACKGROUND: Three-dimensional echocardiography allows calculation of left ventricular ejection fraction without geometric assumption on the ventricular shape. Our aim was to validate this technique in a paediatric population with distorted ventricles. METHODS: Twenty-one patients aged 6 months to 17 years underwent equilibrium radionuclide angiography and three-dimensional echocardiography. Fourteen patients had dilated cardiomyopathy and seven had univentricular hearts. A new, easy to handle, transthoracic rotational probe was used and motion artefacts were limited during the rotation (3 degrees intervals with ECG and respiratory gating). Left ventricular volumes and ejection fraction were calculated using the Simpson's rule with 12 slices. RESULTS: Three-dimensional echocardiography correlated well with equilibrium radionuclide angiography for ejection fraction measurement (r = 0.90; the mean difference between the two methods being 3.8 +/- 6%). Intra-observer and inter-observer variabilities for 3D echocardiography were 2.4% and 4.5%. CONCLUSIONS: Three-dimensional echocardiography is an accurate, non-invasive, and reproducible methods to measure left ventricular ejection fraction in children.

Adolescent↗

An assessment of correlations between endogenous sex hormone levels and the extensiveness of coronary heart disease and the ejection fraction of the left ventricle in males.

This clinical study investigated the possible associations of male sex hormone with the extensiveness of coronary artery lesions, coronary heart disease risk factors and ejection fraction of the heart. Ninety six Caucasian male subjects were recruited, 76 with positive and 20 with negative coronary angiograms. Early morning, prior to haemodynamic examination all of them had determined levels of total testosterone, free testosterone, free androgen index (FAI), sex hormone-binding globulin (SHBG), oestradiol, luteinizing hormone, follicle-stimulating hormone, plasma lipids, fibrinogen and glucose. The ejection fraction and the extensiveness of coronary lesions of each subject was assessed on the basis of x-ray examination results using Quantitative Coronary Angiography (QCA) and Left Ventricular Analysis (LVA) packages on the TCS Acquisition workstation, Medcon. Men with proven coronary heart disease had significantly lower levels of total testosterone (11.9 vs 21.2 nmol/l), free testosterone (45.53 vs 86.10 pmol/l), free androgen index (36.7 vs 47.3 IU) and oestradiol (109.4 vs 146.4 pmol/l). The level of testosterone was negatively associated with the DUKE Index. The most essential negative correlation was observed between SHBG and atherogenic lipid profile (low high-density lipoprotein, high triglycerides). Ejection fraction was substantially lower in patients (51.85 vs 61.30) (without prior myocardial infarction) with low levels of free-testosterone (23.85 vs. 86.10 pmol/l) and FAI (28.4 vs 47.3 IU). A negative correlation was observed between total testosterone, free testosterone, FAI and blood pressure, especially with diastolic pressure. Men with proven coronary atherosclerosis had lower levels of endogenous androgens than the healthy controls. For the first time in clinical settings it has been demonstrated that low levels of free-testosterone was characteristic for patients with low ejection fraction. Numerous hypothesies for this action can be proposed but all require a proper evaluation process. The main determinant of atherogenic plasma lipid was low levels of SHBG suggesting its main role in developing atheroscerotic lesions.

Adult↗

Heart rate turbulence and left ventricular ejection fraction in Chagas disease.

AIMS: Chagas disease patients often present premature ventricular complexes (PVCs), depression of left ventricular ejection fraction (LVEF) and autonomic dysfunction, which is generally evaluated by heart rate variability (HRV) analysis. As frequent PVCs may complicate HRV computation, we measured heart rate turbulence (HRT) and evaluated the correlation between ejection fraction and HRT or HRV in Chagas disease. METHODS: We studied 30 patients (47+/-11 years, 20 men) with Chagas cardiomyopathy and left ventricular dilatation who underwent clinical evaluation, ejection fraction (EF: 45+/-14%) determination and 24-h Holter monitoring (median PVC=1781). In all patients, the standard deviation of normal RR intervals (SDNN), the square root of the mean square differences of successive RR intervals (RMSSD) and values of turbulence onset (TO) and turbulence slope (TS) were calculated. RESULTS: HRT indices were independent of mean RR interval and presented high correlation with EF: TO (-0.11+/-0.01%, r=-0.60, P<0.001) and TS (5.8+/-3.7 ms/RR-interval, r=0.73, P<0.001). Of HRV parameters, only SDNN, corrected for mean RR interval, showed a weak but not significant correlation with EF (r=0.41). The comparison of HRT/EF and HRV/EF correlation coefficients, indicated the presence of a significant difference (P=0.017). CONCLUSIONS: HRT indices appear to correlate better with EF than SDNN in Chagas disease. Thus, an analysis based on heart rate transient adaptation seems to perform better than HRV in detecting the autonomic alterations that parallel left ventricular dysfunction in Chagas disease patients. The high number of PVCs observed in these patients further support the use of HRT methodology.

Adult↗

[Use of fourier row as a method for analyzing the course of circadian heart rate in patients with left ventricular ejection fraction impairment].

The circadian heart rate course was assessed in 3 groups of patients with left ventricular ejection fraction (LVEF) 10-15%, 20-25% and 30-35%. The study comprised 36 persons. In 9 patients heart failure was due to MI and in 17--to dilated cardiomyopathy. Those with atrial fibrillation, ventricular tachycardia, supraventricular tachycardia, diabetes, valvular heart diseases and with central system disorders were excluded from the study. Left ventricular ejection fraction was evaluated by echocardiography. Heart rate, calculated as a mean value every 5 minutes, was taken in patients during 24 hour recordings. For each patient separately, mean value of all measurement was calculated. Then a ratio of each actual value to the mean value was calculated. This ratio was defined as relative heart rate; [formula: see text] Circadian heart rate courses were approximated by Fourier row: [formula: see text]. The 24 harmonics were analyzed. Statistically significant differences in circadian courses were closed to amplitudes of 1st, 12th, 13th, 14th, 16th, 18th harmonics. Using test of variance homogeneity it has been demonstrated that variability of amplitudes of 12th and 17th harmonics as well as phase of 5th harmonic depend on left ventricular ejection fraction.

Adult↗

Ejection fraction velocity ratio as an indicator of aortic stenosis severity.

BACKGROUND: Despite the widespread use of the continuity equation in the estimation of aortic valve area (AVA) in patients with aortic stenosis, it is subject to errors, time consuming, and can be technically demanding. As such, simpler methods of assessing aortic stenosis severity have been pursued. METHODS: The ejection fraction velocity ratio [EFVR = ejection fraction (%) / maximal aortic velocity (m/sec)] was compared to AVA determined with the continuity equation in 857 patients with aortic stenosis and varying degrees of LV systolic dysfunction. Severe aortic stenosis was defined as an AVA < 1.0 cm2. RESULTS: There was good to excellent correlation between our index and aortic valve area (P < 0.001 for each ejection fraction subgroup). Receiver operating characteristic analysis showed that the EFVR functioned well with areas under the curve between 0.893 and 0.938. CONCLUSION: The EFVR is a simple noninvasive method for screening patients for an AVA of 1.0 cm2. It could be used as a screening test or in lieu of the continuity equation particularly when there is problematic measurement of either the LVOT diameter or velocity.

Aged↗

[Determining left and right ventricular volume ejection fractions (VEF) with MRI at 1.0 T. Comparison of manual and semi-automated endocardium detection].

PURPOSE: To evaluate method- and user effects as well as the required time in the determination of left- and right ventricular ejection fractions in comparing manual and semiautomatic border detection of the endocardium. METHODS: In 22 patients with varying cardiac diseases endocardial borders were detected either manually or semi-automatically (seeded ROI) and subsequently the right and left ventricular volume ejection fractions were computer-calculated. Two investigators defined the endocardial borders for both ventricles using both methods. For statistical analysis two-factorial analyses of variance were performed for the four variables: VEF right ventricle, VEF left ventricle, required time right ventricle, required time left ventricle (SAS, Anova). RESULTS: There was no user or method effect detectable for both ventricles. The required time for both ventricles also did not reveal a user effect, but there was a dramatic method effect concerning a reduction of the required time for analysis for both ventricles > 50%. CONCLUSIONS: The semiautomatic mode for detecting the endocardial borders in determining right and left ventricular ejection fractions did not demonstrate results differing from the results of the manual method, but is significantly superior concerning the time required for analysing ejection fractions of both ventricles with a reduction of over 50%. This might significantly reduce the expenditure for personnel.

Adult↗

Right and left ventricular volume and ejection fraction by tomographic gated blood-pool scintigraphy.

UNLABELLED: Tomographic techniques separate overlying structures, permitting measurements of absolute ventricular volumes. The purpose of this study was to determine absolute right and left ventricular volume and ejection fraction measurements with tomographic gated equilibrium blood-pool scintigraphy (TMUGA) compared to MRI and conventional planar scintigraphy. METHODS: Eighteen patients were studied. Ventricular volumes for TMUGA and MRI were calculated by modified Simpson's rule. TMUGA regions were defined by constraints including phase analysis, intensity threshold and visual inspection. MRI studies were acquired with a fast gradient-echo, ECG-gated, breath-hold technique and boundaries were defined by a semiautomated contour method. Conventional gated first-pass radionuclide angiography (FP) and planar gated equilibrium blood-pool scintigraphy (PMUGA) were performed for RV EF and LV EF, respectively. RESULTS: TMUGA absolute right ventricular volumes showed excellent-correlation with MRI for both right ventricular volumes (r = 0.91, slope = 0.90, s.e.e. = 15.7) and left ventricular volumes (r = 0.96, slope = 0.88, s.e.e. = 18.2). For left ventricular ejection fraction, TMUGA also showed excellent correlation with MRI (r = 0.94, slope = 1.10, s.e.e. = 9.0) and planar MUGA (r = 0.97, slope = 1.23, s.e.e. = 6.2). For right ventricular ejection fraction, TMUGA showed good correlation with both MRI (r = 0.88, slope = 0.79, s.e.e. = 6.0) and first-pass planar scintigraphy (r = 0.86, slope = 1.2, s.e.e. = 7.9). CONCLUSION: Tomographic gated blood-pool scintigraphy absolute right and left ventricular volumes and ejection fractions show good correlation with accepted techniques. Further studies are necessary to define the reproducibility of this method.

Cardiac Volume↗

Linear discriminant analysis of regional ejection fractions in the diagnosis of coronary artery disease.

We studied the application of linear discriminant analysis to the computer assisted interpretation of rest and exercise gated blood pool studies. Data were obtained in 45 patients in whom the presence or absence of coronary artery disease was determined by coronary angiography. Automated analysis of regional ejection fractions using a linear discriminant function (LDF) was compared to the fully automated calculation of global ejection fraction and to the subjective evaluation of wall motion. A LDF constructed from the data for the first 31 consecutive patients correctly classified 25/31 (81%). The change in global ejection fraction correctly classified 24/31 (77%) and wall motion analysis 25/31 (81%). In a distinct group of 14 patients the same LDF correctly classified 12/14 (86%), global ejection fraction 9/14 (64%) and wall motion analysis 10/14 (71%).

Coronary Disease↗

A new, simple and precise method for the determination of right ventricule forward ejection fraction in first-pass radionuclide cardiography.

A new method is presented for the determination of right ventricular ejection fraction (RVEF) in first-pass radionuclide cardiography. The method is simple to apply and it provides RVEF values with an experimental standard deviation of 3.4% over the whole range of right ventricular ejection fractions. The method determines RVEF from analysis of time-activity curves from regions of interest (ROIs) over representative portions of the right atrium and the pulmonary artery (RVEFRAPA). Hence, the problem of demarcation of the right ventricle from adjacent structures is avoided. RVEFRAPA was 0.658 +/- 0.067 (mean +/- 1 S.D.) in a normal group of 36 adult women. This value was not significantly different from the RVEF of 0.641 +/- 0.072 (mean +/- 1 S.D.) determined by separate areas over the right ventricle in the end-diastole and end-systole (RVEFRVSA). In a repeatability study comprising 25 subjects covering a wide range of RVEF values, the standard deviation of RVEFRAPA was 4.4 times smaller than that of RVEFRVSA. The left ventricular ejection fraction (LVEF) determined in the equilibrium gated radionuclide cardiography following the first-pass study was 0.692 +/- 0.065 (mean +/- 1 S.D.) for the normal group. Hence, LVEF is slightly higher than RVEF in normals.

Adult↗

Therapeutic options in patients with reduced ejection fraction and nonsustained ventricular tachycardia.

The patient with a reduced ejection fraction and nonsustained ventricular tachycardia represents a common management problem for the physician. This article reviews the supporting evidence for the therapeutic options available for these patients according to the etiology of the reduced ejection fraction. In postinfarction patients, electrophysiology-guided implantable cardioverter defibrillator therapy improves survival more than antiarrhythmic therapy. In patients with nonischemic cardiomyopathy, the best therapy is yet undetermined. Ongoing clinical trials will hopefully direct future therapy.

Humans↗

Criteria for the accurate interpretation of changes in left ventricular ejection fraction and cardiac volumes as assessed by rest and exercise gated radionuclide angiography.

Although serial left ventricular ejection fraction and volumetric measurements using gated radionuclide angiography are commonly used to evaluate clinical changes and therapeutic outcomes in individual patients, criteria are not available for accurately interpreting whether a change in any of these hemodynamic measurements is clinically meaningful. Accordingly, the magnitude of inherent variability among sequential measurements of hemodynamic variables assessed by gated radionuclide angiography was investigated in a double-blind placebo-controlled fashion in 39 patients during two placebo periods separated by 6 weeks. All patients analyzed had remained clinically stable during the study period. Although the mean values for all hemodynamic variables between the two placebo periods were minimally changed, the differences in individual patients were striking. Criteria were developed to allow meaningful interpretation of changes in hemodynamic variables by estimating the likelihood that an observed change is due to variability alone. On the basis of this analysis of placebo radionuclide angiographic data, variation due to chance alone is unlikely to account for all variability if a change observed between the two rest gated studies in a patient is greater than or equal to 7% units for left ventricular ejection fraction, greater than or equal to 45 ml/m2 for end-diastolic volume index, greater than or equal to 35 ml/m2 for end-systolic volume index, greater than or equal to 20 ml/m2 for stroke volume index and greater than or equal to 1.25 liters/min per m2 for cardiac index. An observed 4% unit change in left ventricular ejection fraction (increase or decrease) after a medical intervention in an individual patient occurs by random variation greater than 25% of the time.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Volume↗