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Visually estimated left ventricular ejection fraction by echocardiography is closely correlated with formal quantitative methods.

BACKGROUND: Simpson ejection fraction, wall motion score index, atrioventricular (AV) plane displacement and fractional shortening are all established formal echocardiographic methods for the assessment of left ventricular systolic function. Visually estimated (eyeballing) ejection fraction may be considered somewhat more subjective, although shown to correlate well with radionuclide ventriculography. We aimed to explore if echocardiographic eyeballing ejection fraction is comparable to formal methods for the evaluation of left ventricular systolic function. METHODS: We assessed 89 consecutive patients after myocardial infarction or before coronary angiography. Eyeballing ejection fraction and wall motion score index were evaluated in the long-axis, short-axis and apical four- and two-chamber views. Simpson ejection fraction and AV plane displacement were assessed in the apical views. Fractional shortening was measured in the parasternal long-axis view. The respective systolic function measurements were in each patient made at different time points by a single investigator, masked to prior results. RESULTS: All formal methods correlated significantly with eyeballing ejection fraction (p<0.001): AV plane displacement, R=0.647; FS, R=0.684; four-chamber Simpson ejection fraction, R=0.857; biplane Simpson ejection fraction, R=0.898; and wall motion score index, R=0.919. CONCLUSION: Eyeballing ejection fraction correlated closely with all formal methods and the correlation coefficient improved with the reliability of the formal method. This finding is in concordance with prior studies, indicating that eyeballing ejection fraction may be the most accurate echocardiographic method for the assessment of left ventricular systolic function. Since it is readily and quickly performed, eyeballing ejection fraction could be used for routine echocardiography instead of formal methods.

Adult↗

Evaluation of magnetic resonance imaging for determination of left ventricular ejection fraction and comparison with angiography.

Left ventricular ejection fraction was measured by magnetic resonance imaging (MRI) and compared with standard monoplane left ventriculography in 46 patients with various cardiac diseases. Two different MRI strategies were used. In 28 patients (group 1), ejection fraction was determined using a single slice comparable with the right anterior oblique projection of the ventriculogram. Comparison of left ventricular ejection fraction yielded a poor correlation between single slice MRI (y) and ventriculography (x) (y = 28.7 + 0.47 x, r = 0.65). In 18 patients (group 2), a multiple contiguous slice MRI technique was used to allow ejection fraction and stroke volume determination by summing up the volumes of ventricular cavity intersections. Regression analysis showed a high correlation between multiple slice MRI (y) and ventriculography (x) (y = 7.2 + 0.88 x, r = 0.98). Also, correlation between MRI right (y) and left (x) ventricular stroke volumes was satisfactory, (y = -12.8 + 1.09 x, r = 0.83). It is concluded that the multiple slice imaging technique in MRI provides an accurate noninvasive means for quantification of left ventricular ejection fraction that can be extended to the determination of left ventricular volume.

Angiocardiography↗

Mortality and morbidity after coronary artery bypass surgery related to pre-operative left ventricular ejection fraction: a follow-up study.

OBJECTIVE: To study the pre-operative level of left ventricular ejection fraction that may be indicative of an increased risk of early and late mortality and of recurrent angina pectoris and late non-fatal myocardial infarction. MATERIAL AND METHODS: A total of 934 patients with known left ventricular ejection fraction, 80 women and 854 men, were submitted to coronary artery bypass grafting at the Cardiovascular Unit of Rikshospitalet, Oslo, between August 1982 and December 1986. The closing date was the 1st of January 1993, with a mean follow-up of time of 7.4 years. The patients were divided in to four subgroups according to their level of left ventricular ejection fraction: < or = 40%, 41-60%, 61-80% and > 80%. The left ventricular ejection fraction varied from 13-98%. A chi-square test of linear trend was used to calculate the relative risk between the different subgroups. Cumulative survival was determined using survival curves. RESULTS: Early mortality. Twenty-five patients (2.7%) died within 30 days of operation. Patients with left ventricular ejection fraction < or = 40% had a relative risk of 10.2 (1.9-17.2), for left ventricular ejection fraction 41-60% the relative risk was 0.9 (0.1-8.9) and for left ventricular ejection fraction 61-80% the relative risk was 2.8 (0.6-17.2). Left ventricular ejection fraction > 80% was defined as relative risk = 1. Late mortality. Altogether, 174 patients died in the late phase (18.6%). For patients with left ventricular ejection fraction < or = 40% the relative risk was 3.6 (2.8-10.9), for left ventricular ejection fraction 41-60% the relative risk was 1.8 (1.1-3.6), and for left ventricular ejection fraction 61-80% the relative risk was 1.5 (0.9-2.8). Recurrent angina pectoris. A total of 138 patients developed recurrent angina pectoris during the follow-up period, giving an incidence of 14.8%. Here, for left ventricular ejection fraction < or = 40% the relative risk was 0.5 (0.2-1.3), for left ventricular ejection fraction 41-60% the relative risk was 1.0 (0.5-1.8) and for left ventricular ejection fraction 61-80% the relative risk was 1.2 (0.7-2.0). Late non-fatal myocardial infarction. Altogether, 90 patients (9.6%) experienced non-fatal myocardial infarction in the late phase. For left ventricular ejection fraction < or = 40% the relative risk was 0.6 (1.2-1.8), for left ventricular ejection fraction 41-60% the relative risk was 1.0 (0.5-2.0) and for left ventricular ejection fraction 61-80% the relative risk was 0.7 (0.41-1.3). Cumulative survival. When pooled together, the cumulative survival for patients with left ventricular ejection fraction > 40% was 95.9, 91.9 and 79% after 1, 5 and 10 years, respectively. For the patients with left ventricular ejection fraction < or = 40% cumulative survival was 87.5, 73.1 and 55.2%, respectively. CONCLUSION: When the left ventricular ejection fraction was 40% or lower, there was a substantial increase in the risk of early mortality in patients submitted to coronary artery bypass grafting. As for the risk of late mortality, there was a practically linear increase in risk with falling values of left ventricular ejection fraction. We found no difference in risk of developing recurrent angina pectoris or of late non-fatal myocardial infarction related to values of left ventricular ejection fraction.

Aged↗

Accuracy of left ventricular ejection fraction determined by the nuclear stethoscope.

We assessed left ventricular ejection fraction 47 times in 21 patients with sinus rhythm by a portable non-imaging nuclear probe. After 99mTc blood pool labelling, left ventricular ejection fraction was determined by probe in two different ways: on a beat-to-beat basis, and by the so-called ventricular function mode, based on the gated equilibrium principle, and subsequently compared with left ventricular ejection fraction measured by gated equilibrium radionuclide angiocardiography using a gamma camera. Left ventricular ejection fraction by probe correlated well with left ventricular ejection fraction by gamma camera: beat-to-beat versus gamma camera: r = 0.90, y = 0.75x + 0.12; ventricular function versus gamma camera: r = 0.88, y = 0.87x + 0.08. Also, left ventricular ejection fraction values determined by the two probe methods correlated closely: r = 0.97, y = 0.83x + 0.07. Compared with the gamma camera, the probe overestimated slightly the small values of left ventricular ejection fraction and underestimated high values. Correct determination of left ventricular ejection fraction by a non-imaging probe depends on correct positioning over the left ventricle and selection of a proper background activity level. The main application of this instrument is probably non-invasive bedside determination and monitoring of changes of left ventricular function occurring spontaneously or caused by cardiac arrhythmias or treatment with cardiac drugs.

Adult↗

Radionuclide angiographic assessment of left ventricular function during exercise in patients with a severely reduced ejection fraction.

To study the effect of exercise on left ventricular ejection fraction in patients with congestive cardiomyopathy and the relation of the response to the origin of the myocardial dysfunction, 30 patients with a severely reduced ejection fraction (30 percent or less) were evaluated with radionuclide angiography. Group I consisted of 16 patients with ischemic cardiomyopathy and a mean (+/- standard deviation) resting ejection fraction of 22.3 +/- 6.1 percent. Group II was composed of 14 patients with primary cardiomyopathy and a mean resting ejection fraction of 19.3 +/- 4.7 percent. The mean age, left ventricular end-diastolic pressure, cardiac index and resting left ventricular ejection fraction of Groups I and II were similar; however, the change in the ejection fraction during similar levels of exercise differed significantly. The mean exercise ejection fraction decreased to 16.7 +/- 6.8 percent in Group I, but increased to 24.6 +/- 6.4 percent in Group II (p less than 0.001). Thus, exercise usually results in a directionally opposite change in left ventricular ejection fraction depending on the origin of the congestive cardiomyopathy.

Adult↗

Two-dimensional echocardiographic estimation of right ventricular ejection fraction in patients with coronary artery disease.

Two-dimensional echocardiographic determination of right ventricular ejection fraction was compared with right ventricular ejection fraction obtained by first pass radionuclide angiography in 39 patients with coronary artery disease. Apical four chamber and two chamber right ventricular views were obtained in 34 (87%) of the 39 patients, while a subcostal four chamber view was obtained in 31 patients (80%). Right ventricular ejection fraction by two-dimensional echocardiography was calculated by the biplane area-length and Simpson's rule methods using two paired orthogonal views and utilizing a computerized light-pen method for tracing the right ventricular endocardium. A good correlation (r = 0.74 to 0.78) was found between radionuclide angiographic and two-dimensional echocardiographic right ventricular ejection fraction for each method used. Patients with acute inferior myocardial infarction had the lowest right ventricular ejection fraction by radionuclide angiography and two-dimensional echocardiography (p less than 0.05 compared with patients with right coronary artery obstruction and no infarction). There were no differences in right ventricular ejection fraction between patients with acute and old inferior myocardial infarction by both techniques. No correlation was found between left and right ventricular ejection fraction by radionuclide angiography (r = 0.16). It is concluded that 1) right ventricular ejection fraction by two-dimensional echocardiography correlates well with radionuclide angiographic measurements and can reliably evaluate right ventricular function in coronary artery disease, 2) patients with inferior myocardial infarction have reduced right ventricular ejection fraction, and 3) changes in left ventricular ejection fraction do not directly influence right ventricular function.

Adult↗

Lack of agreement between measurement of ejection fraction by impedance cardiography versus radionuclide ventriculography.

OBJECTIVE: To determine the limits of agreement between left ventricular ejection fraction estimated using systolic time intervals from impedance cardiography and left ventricular ejection fraction estimated by radionuclide ventriculography. DESIGN: A prospective study for diagnostic tests using radionuclide ventriculography as the criterion standard. SETTING: A large military teaching hospital. PATIENTS: Twenty ambulatory adults scheduled for radionuclide ventriculography. MEASUREMENTS AND MAIN RESULTS: A regression equation to estimate ejection fraction from systolic time intervals is available in a widely used impedance-based cardiac monitoring device. The estimated ejection fraction is then used in an equation with stroke volume estimated by the same device to calculate an end-diastolic volume. We studied the agreement of the ejection fraction as estimated by this device with the ejection fraction estimated by radionuclide ventriculography by obtaining simultaneous estimates of ejection fraction over a broad range of adult patients. Twenty ejection fraction pairs were analyzed. The correlation of ejection fraction by impedance cardiography to ejection fraction by radionuclide ventriculography was significant (r2 = .55; p < .002). However, the mean difference between the technologies was -8.85%, with a standard deviation of the differences of 7.15%, resulting in a 95% confidence range for agreement of -23.2% to +5.5%. CONCLUSIONS: The 95% confidence range defining the limits of agreement between ejection fraction by impedance cardiography and ejection fraction by radionuclide ventriculography is not clinically acceptable. In the opinion of the authors impedance cardiography should not be used in place of radionuclide ventriculography for the assessment of ejection fraction at this time.

Adult↗

Serial measurements of left ventricular ejection fraction by radionuclide angiography early and late after myocardial infarction.

The left ventricular ejection fraction was determined serially with radioisotope angiography in 63 patients with acute myocardial infarction. After the peripheral injection of a bolus of technetium-99m, precordial radioactivity was recorded with a gamma scintillation camera and the ejection fraction calculated from the high frequency left ventricular time-activity curve. Since this technique requires no assumptions with respect to left ventricular geometry, it is particularly useful in patients with segmental left ventricular dysfunction. Serial measurements during the first 5 days after hospital admission were made in 50 patients, 30 of whom were studied during the subsequent 2 to 39 months (mean 19.9 months). Late follow-up serial studies were also performed in an additional 13 patients who had only one measurement of the left ventricular ejection fraction during the early postinfarction period. Early after infarction, the left ventricular ejection fraction was normal (more than 0.52) in only 15 of the 63 patients, and averaged 0.52 +/- 0.05 (standard deviation) in the 27 patients with an uncomplicated infarct. The ejection fraction was reduced in 24 patients with mild to moderate left ventricular failure (0.40 +/- 0.05, P less than 0.0001) and in the 12 patients with overt pulmonary edema (0.33 +/- 0.07, P less than 0.0001). In 35 patients the ejection fraction correlated with the mean pulmonary arterial wedge pressure (r = 0.72). In 15 patients with normal left ventricular wall motion by heart motion videotracking, the ejection fraction was significantly higher (0.53 +/- 0.08) than in the 26 patients with regional left ventricular dysfunction (0.41 +/- 0.10, P less than 0.0001). During the early postinfarction period, the left ventricular ejection fraction improved in 55 percent of patients and remained unchanged or decreased in 45 percent. A further increase in the ejection fraction was noted in 61 percent of patients during the late follow-up period. Patients with an initially low or decreasing ejection fraction had a significantly greater incidence of early mortality and left ventricular dysfunction (P less than 0.02) than those whose ejection fraction was normal or improved to normal early after infarction. These data indicate that the ejection fraction is a sensitive indicator of left ventricular function after acute myocardial infarction and that serial measurements are helpful in predicting early mortality and morbidity.

Acute Disease↗

Contribution of left ventricular diastolic dysfunction to heart failure regardless of ejection fraction.

Heart failure (HF) has been classified as systolic and diastolic based on the left ventricular ejection fraction. We hypothesized that left ventricular diastolic dysfunction is an important element of HF regardless of ejection fraction. Two hundred six patients who had clinical HF were compared with 72 age-matched controls. Diastolic dysfunction, as assessed by the mitral filling pattern and tissue Doppler imaging, was present in >90% of patients who had HF regardless of ejection fraction and was more frequent and severe than in age-matched controls (p <0.001). In patients who had HF, B-type natriuretic peptide correlated with diastolic dysfunction (r = 0.62, p <0.001) but not with ejection fraction or end-diastolic volume index (EDVI). The degree of diastolic dysfunction influenced survival rate (risk ratio 1.64, p <0.05), whereas ejection fraction and EDVI did not. Systolic function measured by systolic mitral annular velocity was decreased in patients who had HF and an ejection fraction </=0.40 (4.8 +/- 1.1 cm/s) and, to a lesser extent, an ejection fraction >/=0.50 (6.6 +/- 1.8 cm/s) compared with control subjects (8.0 +/- 2.1 cm/s, p <0.01). Patients who had HF and an ejection fraction >/=0.50 had an increased ratio of ventricular mass to EDVI. Patients who had HF and an ejection fraction </=0.40 had increased left ventricular EDVI. Thus, regardless of ejection fraction, patients who have HF also have diastolic dysfunction. Diastolic dysfunction is a better predictor of B-type natriuretic peptide levels and mortality than ejection fraction or left ventricular EDVI. In addition to diastolic dysfunction, HF with an ejection fraction >/=0.50 is associated with mild systolic dysfunction and an increased ratio of left ventricular mass to EDVI. In HF with an ejection fraction </=0.40, systolic dysfunction and left ventricular dilation accompany diastolic dysfunction.

Aged↗

Influence of atrioventricular synchrony on hemodynamics in patients with normal and low ejection fractions following open heart surgery.

The authors wished to test the hypothesis that atrioventricular synchrony has a relatively greater effect on hemodynamic parameters in postoperative patients with low ejection fractions compared to those with normal ejection fractions. Temporary pacing wires were placed on the right atrium and right ventricle of patients undergoing open heart surgery. Duplicate thermodilution cardiac outputs were determined during atrial pacing and ventricular pacing at 100 beats/min. Mean left atrial and systemic blood pressures were monitored. Thirteen patients with ejection fractions of 45 per cent or less (range 24 to 45%, mean 37.3%) were included in the low ejection fraction group, and 27 patients with ejection fractions of 59 per cent or greater (range 59 to 80%, mean 66.8%) were considered in the normal ejection fraction group. All hemodynamic parameters improved significantly when changing from ventricular pacing to atrial pacing in both the normal ejection fraction group and low ejection fraction group (P less than 0.05). The magnitude of change between the groups showed no significant difference for all parameters except left atrial pressure, which decreased by a greater percentage in the low ejection fraction group with atrial pacing (P less than 0.001). The atrial contribution to hemodynamic enhancement is important in patients with normal and low ejection fraction following open heart surgery. Patients with low ejection fractions do not sustain a relatively greater reduction in cardiac output, stroke volume index, or systemic blood pressure with loss of atrioventricular synchrony when compared to patients with normal ejection fractions.

Cardiac Output↗

Dependence of ejection fraction results on choice of algorithms for a cardiac phantom.

Ejection fraction results obtained from the Vanderbilt rotating cardiac phantom exhibit a strong dependence on the algorithms used to derive the time--activity curves and calculate the ejection fraction from those curves. This problem is caused because the background chamber is located behind the rotating attenuator which is used to produce the pseudo ejection fraction. As a result, the counts due to background in both the regions on the 'left ventricle' and the area assigned for background correction do not remain constant during the 'cardiac cycle'. This leads to a breakdown in the ejection fraction algorithms. Given the same data, but changing the methods by which the time--activity curves and ejection fractions are derived, ejection fraction results varying from a minimum of 45% to a maximum of 69% have been demonstrated for the 50% attenuator. Although the Vanderbilt cardiac phantom is simple to operate it must be used with caution if it is used with the intention of calibrating a particular system or comparing different protocols.

Heart↗

Risk stratification and management of patients with organic heart disease and nonsustained ventricular tachycardia: role of programmed stimulation, left ventricular ejection fraction, and the signal-averaged electrocardiogram.

PURPOSE: Programmed stimulation, left ventricular ejection fraction, and signal-averaged electrocardiography were performed in patients with organic heart disease and spontaneous nonsustained ventricular tachycardia (VT) to determine the role of these techniques in risk stratification and management. PATIENTS AND METHODS: The study consisted of 90 patients: 63 had coronary artery disease and 27 had idiopathic dilated cardiomyopathy. Radionuclide ventriculography, signal-averaged electrocardiography, and programmed electrical stimulation were performed in all patients within 48 hours of index ambulatory electrocardiography. RESULTS: Fifty-three patients (59%) had an ejection fraction less than 40%. Programmed stimulation induced sustained monomorphic VT in 22 patients (24%), ventricular fibrillation (VF) in 10 patients (11%), and no sustained VT/VF in 58 patients (64%). The signal-averaged electrocardiogram (ECG) showed late potentials in 23 patients (26%). Sustained monomorphic VT could be induced in 65% of patients with late potentials and in 10% of those without late potentials. There was no case of inducible sustained monomorphic VT in 33 patients with no late potentials and an ejection fraction of 40% or greater. All patients with induced sustained monomorphic VT received antiarrhythmic therapy guided by the results of programmed stimulation. All 58 patients with no induced sustained ventricular tachyarrhythmias and eight patients with induced VF were discharged without receiving antiarrhythmic drugs. During a follow-up of 30 +/- 10 months, the three-year sudden death rate was 19% in patients with induced sustained VT, 0% in those with induced VF, and 9% in those with no induced sustained VT/VF. The three-year sudden death rate was the same (7%) in patients with no induced sustained VT/VF, both in those with an ejection fraction of 40% or greater or less than 40%. On the other hand, the three-year total cardiac mortality was significantly higher (27%) in those patients with ejection fractions less than 40% compared to those with ejection fractions of 40% or greater (7%). CONCLUSION: It is concluded that the signal-averaged ECG, ejection fraction, and programmed stimulation could be used for the risk stratification and management of patients with organic heart disease and nonsustained VT as follows: (1) Patients with no late potentials and with an ejection fraction of 40% or greater do not require invasive evaluation or antiarrhythmic therapy, since the incidences of induced VT and sudden death are very low. (2) Patients with late potentials as well as patients without late potentials but with an ejection fraction of less than 40% may be advised to undergo electrophysiologic evaluation.(ABSTRACT TRUNCATED AT 400 WORDS)

Anti-Arrhythmia Agents↗

Superiority of visual versus computerized echocardiographic estimation of radionuclide left ventricular ejection fraction.

An optimal method for determining left ventricular ejection fraction (LVEF) by echocardiography should be rapid, reliable, and widely applicable in order to be utilized routinely in a busy clinical laboratory. Most methods reported in the literature are reliable in selected, high-quality echocardiograms. Most require off-line computer analysis and are time-consuming and poorly suited to the routine of a busy laboratory. We compared in a blinded manner several echocardiographic methods of LVEF determination with the ejection fraction obtained by equilibrium radionuclide angiography (ERNA) in 44 patients unselected for image quality. Echocardiographic methods included: [1] cubed M-mode formula; [2] Teichholz M-mode formula; [3] subjective estimation of LVEF from two-dimensional echocardiographic videotape; [4] area-length method in one four-chamber view; [5] average of area-length method in three four-chamber views; [6] average of area-length method in four-chamber and two-chamber views (one beat each); [7] subjective estimation from stored videoloop of four-chamber and two-chamber view. In 30 cases M-mode tracings were available for analysis. In only 23 of the 44 patients were the apical views suitable for quantitative analysis. The ERNA ejection fraction was 44 +/- 17% (mean +/- 1 SD). The best echocardiographic correlation with ERNA ejection fraction in each patient subgroup studied was obtained by method 3. We concluded that subjective analysis of the videotaped study by an experienced cardiologist/echocardiographer provided the best estimation of ERNA ejection fraction. More time-consuming and costly computer techniques yielded a worse estimate.

Adult↗

Systolic dysfunction in heart failure with a normal ejection fraction: echo-Doppler measurements.

Heart failure with a normal ejection fraction, also called heart failure with preserved ejection fraction or diastolic heart failure, is thought to be characterized by normal systolic function and disturbed diastolic function only. However, studies using newer Doppler-echocardiographic techniques have shown that ventricular function is not normal particularly in the long axis. Ejection is relatively preserved because of increased radial function. Similar findings are seen with normal ageing and the typical precursors of heart failure with a normal ejection fraction such as hypertension, diabetes, and ischemia. There appears to be a spectrum of abnormalities of systolic function from the truly normal to systolic heart failure with heart failure with a normal ejection fraction occupying an intermediate position. The use of ejection fraction, which has a normal distribution, to dichotomize patients with heart failure is not supported on theoretical or experimental grounds, and any cutoff is arbitrary. Patients with heart failure have a mixture of systolic and diastolic abnormalities and variable degrees of remodeling. It is more important to correctly identify these in the individual patient.

Diastole↗

Early two-dimensional echocardiographic measurement of left ventricular ejection fraction in acute myocardial infarction.

Left ventricular volume and ejection fraction were measured by 2-dimensional echocardiography from 2 orthogonal apical long axis views in 90 patients admitted with acute transmural myocardial infarction. Results were correlated with worst Killip class during hospital stay, enzymatic infarct size (peak CK-MB) and mortality. We used two algorithms, a biplane area-length algorithm and a modification of Simpson's rule. Both algorithms yielded essentially the same results: there were statistically significant trends towards higher end-diastolic and end-systolic volumes and lower ejection fraction with higher Killip -class. Ejection fraction was lower (P less than 0.01) in the 6 patients dying from cardiogenic shock (28.0 +/- 7.8% v. 46.6 +/- 10.1% in survivors with the area--length algorithm; 28.1 +/- 6.2% v. 48.1 +/- 10.2% with modified Simpson's rule). In 5 patients dying from other causes ejection fraction was 46.0 +/- 14.9% with the area-length method or 46.2 +/- 14.5% with Simpson's rule (not different from survivors). Correlation with peak CK-MB was only modest, though statistically significant: the regression equation was: y = -0. 39x + 54 (r = -0.35; P less than 0.01) with the area-length method; and y = -0. 41x + 55 (r = -0.37; P less than 0.01) with Simpson's rule. Left ventricular ejection fraction measured at the bedside in patients with acute myocardial infarction, can provide useful clinical information. Patients likely to develop shock can be identified shortly after admission.

Aged↗

[Relationship between right ventricular ejection fraction and pulmonary pressure in man].

This clinical study analysed the changes in right ventricular ejection fraction induced by changes in right ventricular afterload using a new thermodilution catheter linked to a rapid response computer which allowed instantaneous measurements of the right ventricular ejection fraction. The first group comprised 16 patients referred for coronary angioplasty with single vessel disease (isolated proximal stenosis of one of the two main branches of the left coronary artery) and a normal left ventricular ejection fraction (> or = 55%) and mean pulmonary artery pressure of < 25 mmHg: right ventricular ejection fraction and mean pulmonary artery pressure were measured under basal conditions and after 60 seconds' coronary occlusion with the balloon catheter in order to assess the effects of the reactional increase in afterload on the right ventricular ejection fraction. The second group comprised 11 patients with dilated primary cardiomyopathy with decreased left ventricular ejection fraction (< 50%) and mean pulmonary artery pressure > or = 25 mmHg: the right ventricular ejection fraction and mean pulmonary artery pressure were measured under basal conditions and after intravenous trinitrin (performed to evaluate the pulmonary reaction to vasodilators) in order to analyse the effects of the reduction of afterload on right ventricular ejection fraction. Negative linear correlations were observed between the right ventricular ejection fraction and mean pulmonary artery pressure under basal conditions (r = -0.72; p < 0.005) and between the right ventricular ejection fraction and mean pulmonary artery pressure after changing the conditions of afterload (r = -0.82; p < 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Long-term stepwise sustained improvement in left ventricular ejection fraction after myocardial infarction.

Radionuclide left ventricular ejection fraction, end-diastolic volume, and exercise capacity were determined in 34 selected patients who survived a first Q wave anterior infarction. Patients were included in the study if they had no subsequent cardiac events (unstable angina or myocardial infarction) during the average follow-up period of 47 months (range = 36 to 70 months); none was treated with thrombolysis, coronary angioplasty, or bypass grafting. Overall, mean left ventricular ejection fraction increased from 28 +/- 10% 1 month after infarction to 33 +/- 10% at 3 years (p less than 0.01); mean end-diastolic volume decreased from 217 +/- 99 ml to 171 +/- 80 ml (p less than 0.002). Stepwise improvement in left ventricular ejection fraction occurred in 15 of these patients (group B) and was associated with a significant increase in exercise capacity. Mean ejection fraction in group B was 26 +/- 7% at 1 month and 41 +/- 10% at 3 years (p less than 0.001). In all of these patients there was improved regional wall motion in the noninfarct zone, whereas five patients also showed improvement in the infarct zone. The results indicate a progressive improvement in left ventricular function that occurs over time in some patients after first Q wave anterior infarction, independent of intervention.

Adult↗

Performance of a fully automated program for measurement of left ventricular ejection fraction.

A fully automated program developed by us for measurement of left ventricular ejection fraction from equilibrium gated blood pool studies was evaluated in 130 additional patients. Both 6-min (130 studies) and 2-min (142 studies in 31 patients) gated blood pool studies were acquired and processed. The program successfully generated ejection fractions in 86% of the studies. These automatically generated ejection fractions were compared with ejection fractions derived from manually drawn regions of interest. When studies were acquired for 6-min with the patient at rest, the correlation between automated and manual ejection fractions was 0.92. When studies were acquired for 2-min, both at rest and during bicycle exercise, the correlation was 0.81. In 25 studies from patients who also underwent contrast ventriculography, the program successfully generated regions of interest in 22 (88%). The correlation between the ejection fraction determined by contrast ventriculography and the automatically generated radionuclide ejection fraction was 0.79.

Cardiac Output↗