Determination of diastolic function by radionuclide ventriculography

Congestive heart failure with normal ejection fraction

Clinicians must remain undaunted when history, physical examination, and chest radiography suggest congestive heart failure but left ventricular systolic function is normal. Many of these patients have diastolic dysfunction, and standard therapy for left ventricular systolic dysfunction is often ineffectual or detrimental. Noninvasive testing is subject to many pitfalls but may confirm a clinical suspicion and provide indications to treat or to proceed with invasive testing. In the absence of clinical signs and symptoms of congestive failure, however, abnormal diastolic indexes should not be interpreted as diagnostic of diastolic dysfunction and are not an indication to treat.

EANM/ESC guidelines for radionuclide imaging of cardiac function

Radionuclide imaging of cardiac function represents a number of well-validated techniques for accurate determination of right (RV) and left ventricular (LV) ejection fraction (EF) and LV volumes. These first European guidelines give recommendations for how and when to use first-pass and equilibrium radionuclide ventriculography, gated myocardial perfusion scintigraphy, gated PET, and studies with non-imaging devices for the evaluation of cardiac function. The items covered are presented in 11 sections: clinical indications, radiopharmaceuticals and dosimetry, study acquisition, RV EF, LV EF, LV volumes, LV regional function, LV diastolic function, reports and image display and reference values from the literature of RVEF, LVEF and LV volumes. If specific recommendations given cannot be based on evidence from original, scientific studies, referral is given to "prevailing or general consensus". The guidelines are designed to assist in the practice of referral to, performance, interpretation and reporting of nuclear cardiology studies for the evaluation of cardiac performance.

Imaging three-dimensional cardiac function

The three-dimensional (3-D) nature of myocardial deformations is dependent on ventricular geometry, muscle fiber architecture, wall stresses, and myocardial-material properties. The imaging modalities of X-ray angiography, echocardiography, computed tomography, and magnetic resonance (MR) imaging (MRI) are described in the context of visualizing and quantifying cardiac mechanical function. The quantification of ventricular anatomy and cavity volumes is then reviewed, and surface reconstructions in three dimensions are demonstrated. The imaging of myocardial wall motion is discussed, with an emphasis on current MRI and tissue Doppler imaging techniques and their potential clinical applications. Calculation of 3-D regional strains from motion maps is reviewed and illustrated with clinical MRI tagging results. We conclude by presenting a promising technique to assess myocardial-fiber architecture, and we outline its potential applications, in conjunction with quantification of anatomy and regional strains, for the determination of myocardial stress and work distributions. The quantification of multiple components of 3-D cardiac function has potential for both fundamental-science and clinical applications.

Doppler diastolic filling indexes in relation to disease states

This study compares mean Doppler-derived diastolic filling indexes in a variety of disease states in a large, population-based sample. Pulse-wave Doppler was used to examine 880 eligible participants of the Framingham Heart Study. Peak velocity of early flow and late flow, ratio of early to late peak velocities, atrial filling fraction, and early filling wave acceleration and deceleration times were obtained. Multiple linear regression analyses were performed comparing mean values for individuals with hypertension, diabetes, coronary disease, cardiovascular disease, and pulmonary disease. Hypertension was associated with a greater peak velocity late flow (0.027 m/sec; 95% confidence interval, 0.006, 0.047; p = 0.011), and diabetes was associated with a larger mean deceleration time (0.12 sec, confidence interval, 0.002, 0.021; p = 0.016). In multivariate analyses, hypertension continued to show a strong association with altered Doppler diastolic filling patterns, p value 0.009, whereas in diabetes, the multivariate p value was 0.28.

The assessment of left ventricular filling dynamics using an online automatic border detection algorithm: comparison with cineventriculography

An echocardiographic system has been developed that performs automatic endocardial border detection and instantaneously calculates and displays a waveform of left ventricular cavity area versus time. The purpose of this study was to compare measurements of left ventricular filling dynamics from automatic border detection echocardiography with similar measurements from cineventriculography. Thirty-three patients undergoing cardiac catheterization had automatic border detection echocardiography performed within 45 minutes of cineventriculography. Ten patients had normal catheterization findings and 23 had cardiac disease. The automatic border detection waveforms generated from two echocardiographic views were measured to determine the fraction of filling occurring during the early diastolic rapid filling phase and during the filling phase resulting from atrial contraction. Similar fractions were derived from curves generated from frame-by-frame measurements of cineangiographic volumes. Results were analyzed by correlating echocardiographic and cineventriculographic results, and by a limits of agreement analysis (limits of agreement were +/- 2 standard deviations of the mean difference between echocardiography and cineventriculography). There were significant correlations between echocardiography and cineventriculography for each of the parameters studied. The best results were obtained for the apical four-chamber view (rapid filling fraction r = 0.72, P < 0.0001, atrial filling fraction r = 0.56, P < 0.001). Differences in filling patterns between normal and abnormal patient groups detected by cineventriculography were also detected by automatic border detection echocardiography. However, broad limits of agreement were observed, that may limit the ability of the automatic border detection system to reliably predict cineventriculographic results in an individual patient. Automatic border detection echocardiography can provide information about left ventricular filling dynamics that is similar to that obtained from frame-by-frame analysis of cineventriculograms. However, the variability in the results may limit the application of the technique in individual patients.

Effects of bisoprolol on left ventricular hypertrophy in essential hypertension

Previous studies have shown that beta-adrenergic blocking drugs can reverse ventricular hypertrophy in patients with systemic hypertension. Thirty patients with essential hypertension and left ventricular hypertrophy were studied at baseline after withdrawing all previous treatments and after 6 months of treatment with 5-20 mg of bisoprolol, a new beta-selective agent, to assess its possible action on left ventricular mass. Three patients did not finish the study. Blood pressure was reduced to below 160/90 mmHg in 22 of the remaining 27 patients. At the end of follow-up, the left ventricular mass (echocardiography) was reduced from 308.1 +/- 89 g to 262.3 +/- 51 g (p < 0.001) and left ventricular mass index from 165 +/- 47.4 g/m2 to 141.03 +/- 26.7 g/m2 (p < 0.001). The ratio of E wave/A wave velocity of transmitral blood flow measured by Doppler increased from 0.86 +/- 0.44 to 1.07 +/- 0.45 (p = 0.005). Peak filling rate, derived from nuclear ventriculography, changed from 2.05 +/- 0.4 EDV/sec before the treatment to 2.23 +/- 0.47 EDV/sec after it (p = 0.0046). Serum lipids as well as other biochemical tests were unchanged. Left ventricular volumes and ejection fraction did not change, and treadmill exercise time increased from 343 +/- 125 seconds to 420 +/- 135 seconds (p = 0.002). Maximal systolic blood pressure during exercise decreased from 197.2 +/- 19.7 mmHg to 182.9 +/- 25.8 mmHg (p = 0.011). There were few side effects. We conclude that bisoprolol reduces left ventricular mass, preserves systolic function, and improves diastolic function of the left ventricle in hypertensive subjects with left ventricular hypertrophy.

Pitfalls in the echo-Doppler assessment of diastolic dysfunction

The Doppler echocardiographic assessment of diastolic function is an essential part of the evaluation of heart failure, pericardial diseases, restrictive and infiltrative cardiomyopathies, and many other conditions. However, the echocardiographic evaluation of diastolic function has several limitations. The sonographer and physician must understand the technical factors, the effects of physiological and pathophysiological conditions, and the dynamics of pseudonormalization, all of which affect the evaluation. This article will review the most recent data essential for the proper performance and interpretation of a transthoracic or transesophageal Doppler echocardiographic examination of diastolic function.