Showing papers in "European Journal of Echocardiography in 2002"

Right Ventricular Diastolic Dysfunction in Arterial Systemic Hypertension: Analysis by Pulsed Tissue Doppler

Abstract: Aims: This study analyses right ventricular longitudinal function in arterial systemic hypertension by pulsed tissue Doppler. Methods and Results: Thirty normotensives and 30 hypertensives, free of cardiac drugs, underwent standard Doppler echocardiography and pulsed tissue Doppler of right ventricular lateral tricuspid annulus and left ventricular lateral mitral annulus. By tissue Doppler, systolic and diastolic measurements were obtained. Hypertensives had higher left ventricular mass and impaired Doppler diastolic indexes, without changes of global systolic function. Tissue Doppler showed reduction of right ventricular E/A ratio and prolongation of relaxation time in comparison with controls (both P <0·00001). In the overall population, the length of tissue Doppler derived right ventricular relaxation time was positively related to right ventricular anterior wall thickness while right ventricular E/A ratio was positively related to E/A ratio of left ventricular mitral annulus (both P <0·00001). These relations remained significant even after adjusting for clinical and echocardiographic confounders by separate multivariate models. Conclusions: Arterial systemic hypertension is associated to right ventricular longitudinal diastolic dysfunction. This dysfunction involves the prolongation of active relaxation, which is independently associated with the degree of right ventricular hypertrophy and the impairment of passive wall properties, which is mainly due to ventricular interaction occurring under left ventricular pressure overload conditions. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Echocardiographic Evaluation of Right Ventricular Function

Abstract: To allow optimal patient management an ideal measure of right ventricular performance should give an accurate objective assessment of function, be practicable in everyday clinical use and provide accurate prognostic information. This review will provide the practising clinician with an understanding of the advantages and disadvantages of the available echocardiographic techniques and aims to give some guidance on the most useful methods in specific clinical circumstances. The use of non-echocardiographic methods will also be discussed.

Rationale of Echocardiographic Assessment of Left Ventricular Wall Stress and Midwall Mechanics in Hypertensive Heart Disease

Abstract: Active reduction of left ventricular chamber size during systole is the final effect of complex interaction mechanisms involving layers of differently oriented myocardial fibres, the shortening of which is less than the one measured as shortening of the left ventricular diameter at the level of the endocardium. This biological phenomenon is particularly evident in conditions such as arterial hypertension in which left ventricular geometry is altered. Due to the double effect of contraction on both the longitudinal (shortening) and transverse (thickening) axes of the myocardial fibres, the shortening of single myocardial fibres is amplified at the level of the endocardium and this amplification is a function of wall thickness. Increased wall thickness can enhance at the endocardial level the effect of myocardial fibres with reduced shortening, allowing preservation of ejection fraction despite depressed midwall shortening, through a 'contractile gradient' proceeding from epicardium to endocardium. This is detectable using tagged MRI or even quantitative echocardiography. This discrepancy between chamber and wall mechanics, seen in arterial hypertension and in other clinical conditions characterized by alteration of left ventricular geometry, is at the basis of the better prediction of cardiovascular risk in hypertensive patients by measures of left ventricular wall mechanics than by measures of left ventricular chamber function.

Analysis of temporal requirements for myocardial tissue velocity imaging.

Abstract: Aims: Movements of myocardial walls include components of high velocity and short duration calling for a high sampling rate in the acquisition of tissue velocity imaging data. This study aims at establishing the optimal sampling requirements for tissue velocity imaging measurements. Methods and Results: In 16 healthy individuals, tissue velocity imaging data were acquired at a frame rate of 141–203 frames/s for a subsequent off-line analysis using software enabling a reduction of the sampling rate to 50%, 25% and 12.5% of the initial frame rate. Different components of the myocardial velocity profile were measured at each of these frame rates. The deviation of the results from the initial values increased markedly at decreasing frame rates, producing an underestimation of peak systolic and diastolic velocities, most other measured parameters being overestimated. A cut-off point for an acceptable 10% deviation of the results corresponded to at least 70 frames/s for peak systolic and early diastolic velocity, and to at least 100 frames/s for other systolic and diastolic parameters. Conclusion: A high sampling rate is essential for a proper rendering of tissue velocity imaging signals, too low frame rates resulting in inferior accuracy of the results. This should be kept in mind while viewing reported tissue velocity imaging data.

Quantitative assessment of right ventricular volumes in severe chronic thromboembolic pulmonary hypertension using transthoracic three-dimensional echocardiography: changes due to pulmonary thromboendarterectomy.

Abstract: Aims: Evaluation of a three-dimensional reconstruction method to show the changes of right ventricular volume and systolic function when patients undergo pulmonary thromboendarterectomy for chronic thromboembolic pulmonary hypertension. Methods and Results: In the examination of 11 patients (four female, seven male; age 5610 years) before and after pulmonary thromboendarterectomy, end-diastolic and end-systolic right ventricular volumes were determined as a sum total of the calculated volumes of derived parallel slices of the right ventricle. Using a Tomtec workstation and a Vingmed CFM 800 echocardiography device, the acquired data were ECG-and respiration-triggered in the course of transthoracic examination, using step intervals of 5. The ventricular outline was traced manually on 5 mm

Mitral Inflow and Mitral Annular Motion Velocities in Patients with Mitral Annular Calcification: Evaluation by Pulsed Doppler Echocardiography and Pulsed Doppler Tissue Imaging

Abstract: Aims: We evaluated the relationship between the mitral inflow velocities by pulsed Doppler echocardiography and mitral annular motion velocities by pulsed Doppler tissue imaging in patients with mitral annular calcification. Methods and Results: Fifty-three patients with mitral annular calcification were divided into two groups: severe mitral annular calcification (n=15, mitral annular calcification ≧5 mm in width) and mild mitral annular calcification (n=38, mitral annular calcification <5 mm in width). In addition, 20 patients with hypertensive heart disease (HHD group) and mild left ventricular hypertrophy but no mitral annular calcification and 30 normal individuals (normal group) were studied. The early diastolic mitral inflow velocity (E) was higher in the severe mitral annular calcification group (0·75±0·26 m/s) than in the HHD and normal groups (mild mitral annular calcification, 0·65±0·21; HHD, 0·57±0·24; normal, 0·55±0·15 m/s), and the late diastolic mitral inflow velocity (A) was higher in the severe mitral annular calcification group (1·24±0·23 m/s) than in the other three groups (mild mitral annular calcification, 0·96±0·20; HHD, 0·84±0·23; normal, 0·75±0·13 m/s). In contrast, the early and late diastolic annular velocities (Ea, Aa) were lower in the severe mitral annular calcification group (Ea: 5·7±2·2; Aa: 11·9±4·4 cm/s) than in the other three groups (Ea: mild mitral annular calcification, 8·3±2·5; HHD, 7·7±2·2; normal, 9·0±1·8 cm/s; Aa: mild mitral annular calcification, 14·2±4·1; HHD, 14·3±2·8; normal, 14·2±2·1 cm/s). Mitral valve area was smaller in the severe mitral annular calcification group (2·6±1·0 cm2) than in the other three groups (mild mitral annular calcification, 3·1±0·7; HHD, 4·1±0·7; normal, 4·2±0·9 cm2). In the mitral annular calcification and normal groups, the A correlated inversely with mitral valve area (r=−0·67, P <0·01) and directly with severity of mitral annular calcification (r=0·65, P <0·01), and the Ea correlated inversely with left ventricular wall thickness (r=−0·37, P <0·01) and severity of mitral annular calcification (r=−0·45, P <0·01). Conclusion: Patients with severe mitral annular calcification have higher mitral inflow velocities due to mitral annular restriction and lower mitral annular velocities caused by decreased mitral annular motion and abnormal left ventricular relaxation. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Doppler Characterization of Left Ventricular Diastolic Function in β-Thalassaemia Major. Evidence for an Early Stage of Impaired Relaxation

Abstract: Aims: Doppler echocardiographic studies of left ventricular diastolic function in patients with thalassaemia major have shown conflicting findings. This study was undertaken to compare Doppler echocardiographic parameters of diastolic function among a group of patients with thalassaemia major, a group with thalassaemia intermedia and a group of normal individuals. Methods and Results: 50 patients with thalassaemia major, 38 patients with thalassaemia intermedia and 29 normal subjects were studied. All had normal systolic function. The thalassaemia intermedia patients had larger body surface area and left ventricular mass index than the thalassaemia major patients but less than the controls. The ratios between peak early and late mitral diastolic flow (E/A ratio) were comparable between the three groups. The haematocrit levels were comparable in the two study groups, but the ferritin levels were significantly higher in the thalassaemia major group (P<0·001). Using multiple regression analysis to correct for the influence of heart rate, age and body surface area, we found a prolonged isovolumic relaxation time (P<0·03) and a lower E wave (P<0·001) in the thalassaemia major group as compared to the thalassaemia intermedia group. The isovolumic relaxation time also differed significantly between the thalassaemia groups and the control (P<0·001), suggesting a state of impaired relaxation most notable in thalassaemia major that is probably due to iron overload.

Assessment of muscular ventricular septal defect closure by transcatheter or surgical approach: a three-dimensional echocardiographic study.

Abstract: AIMS: Previous classification of muscular ventricular septal defects (VSDs) visualized on two-dimensional echocardiography relied on artificial divisions of the septum. New visualization of the ventricular septum integrating the third dimension would facilitate communication between cardiologists and surgeons. The objectives of this study were (1) to assess in patients with muscular ventricular septal defects the accuracy of left ventricular three-dimensional echocardiographic reconstructions in demonstrating the position, the size and the tissue rims of the defects; (2) to compare findings by three-dimensional echocardiography with those obtained by surgical and transcatheter approaches. METHODS AND RESULTS: Twenty-six patients, aged from one month to 40 years, with muscular ventricular septal defects underwent three-dimensional echocardiographic study. From the left ventricular three-dimensional echocardiographic reconstructions, the localization, the maximal diameter and the tissue rim of the defect were analysed and compared with surgical or transcatheter findings. Optimal three-dimensional echocardiographic reconstructions were obtained in 22 patients. Nineteen had a single muscular ventricular septal defect and three had multiple muscular ventricular septal defects. The muscular ventricular septal defect localizations were the inlet septum in three, the outlet septum in three, the mid-muscular septum in 14 and the apex in eighth. In 10 patients who underwent surgical closure, the correlation between three-dimensional echocardiography and surgery for muscular ventricular septal defect maximal diameter was y=0 x 95 x +0.13 (r=0.98; P<0.001). The agreement between three-dimensional echocardiographic and intraoperative findings on muscular ventricular septal defect localization were complete. In five patients who underwent transcatheter closure, the mean difference between three-dimensional echocardiographic maximal diameter and stretched diameter was 1 x 8+/-0 x 5 mm. CONCLUSION: The three-dimensional echocardiographic left ventricular views provide a new and easily communicated visualization of various muscular ventricular septal defects. Such new imaging should contribute to the surgical and transcatheter treatments of muscular ventricular septal defects.

Differences between echocardiographic measurements of left ventricular dimensions and function by local investigators and a core laboratory in a 2-year follow-up study of patients with an acute myocardial infarction.

Abstract: Aims: To examine differences in measurements of left ventricular dimensions and function, and prognostic value between local investigators and a core laboratory in a multicentre serial echocardiographic study. Methods and Results: Seven hundred and fifty-six patients with acute myocardial infarction and preserved left ventricular function were examined at baseline and after 3 months with measurements by the biplane Simpson’s method, and followed prospectively from 3 to 24 months. At baseline and 3 months local investigators relative to the core laboratory measured lesser end-diastolic volume by 8 and 6 ml ( P <0·001), end-systolic volume by 3 and 2 ml ( P <0·01), and ejection fraction by 0·0 and 0·6% ( P <0·01), respectively. Local investigators and the core laboratory measured an increase in left ventricular end-diastolic volume of 8·6 and 6·9 ml, and in left ventricular end-systolic volume of 5·2 and 4·3 ml, and a decrease in left ventricular ejection fraction of 0·6 and 0·0%. Using the Cox proportionate hazards model, the prognostic value for subsequent clinical endpoints was significant both for the 3-month values ( P <0·05) and changes ( P <0·005) measured by the core laboratory, but not by local investigators. Conclusion: Only measurements in the core laboratory had significant prognostic value for subsequent clinical endpoints. These results strongly support the use of a core laboratory in studies employing echocardiographic measurements. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Doppler echocardiographic evaluation of right ventricular diastolic function in hypertrophic cardiomyopathy.

Abstract: Aims: Left ventricular diastolic function in patients with hypertrophic cardiomyopathy has been adequately studied. In contrast there are few studies concerning right ventricular diastolic function in hypertrophic cardiomyopathy. We studied right ventricular diastolic function in patients with hypertrophic cardiomyopathy using Doppler echocardiography. Methods and Results: We studied 20 patients with hypertrophic cardiomyopathy (mean age 43·613·8 years) and 20 healthy volunteers (control group, mean age 4313·8 years). We calculated left ventricular and right ventricular diastolic indices using pulsed Doppler echocardiography. Hypertrophic cardiomyopathy patients compared with controls had significantly lower right ventricular–E/A ratio (1·010·40 vs 1·300·28, P<0·04), significantly prolonged right ventricular isovolumic relaxation time (17072 vs 3223 ms, P<0·001), and also significantly prolonged right ventricular deceleration time (16058 vs 11835 ms, P<0·01). There was also strong significant correlation between right ventricular deceleration time and left ventricular deceleration time (r=0·78), right ventricular–E/A ratio and left atrial filling fraction (r=0·55) and between right atrial filling fraction and left atrial filling fraction (r=0·75). Conclusions: Right ventricular diastolic function in patients with hypertrophic cardiomyopathy is impaired, reflecting abnormal relaxation. Right ventricular diastolic indices correlate well with those of left ventricle.

The Difference Between Colour Doppler Velocity Imaging and Power Doppler Imaging

Abstract: The Doppler effect, which occurs on the reflection of ultrasound from moving blood or tissue, is observed as a shift in frequency of the reflected ultrasound from that of the incident ultrasound. This Doppler shift has been widely used in clinical practice as a means of measuring blood velocity. Two types of Doppler Imaging are often discussed as facilities on ultrasonic scanners, namely Colour Doppler Velocity Imaging and Power Doppler Imaging. In this article the difference between the two will be described and it will be noted that, although both are used in vascular disease, Power Doppler Imaging is not extensively used at present in cardiology. A number of other names are used for these Doppler techniques, for example ’Normal Doppler’ for Colour Doppler Velocity Imaging and ’Energy Doppler’ for Power Doppler. The echocardiographer is obliged to ascertain what exactly each name stands for. Simple Doppler devices that provide velocity information when their beam is directed at a blood vessel have been available for many years. Indeed images can be produced by these devices if a narrow ultrasound beam is slowly moved across a blood vessel and the blood velocity at each position displayed on a screen. However real-time Doppler imaging only became available when a breakthrough was made in fast signal processing. By ’real-time imaging’ we mean the production of several images per second of the scanned region. The fast signal processing rapidly produces values of the mean blood velocity at neighbouring points along the ultrasound beam and allows the beam to be swept quickly to generate a cross-sectional image of regions of blood flow. Static or slow moving tissue does not produce significant Doppler shifts in the reflected ultrasound and is therefore not presented in a Doppler image. Of course a grey shade B-mode image of these tissues is usually combined with the Doppler image. With early instruments, 15 Doppler images per second were typical but now the rate can be in excess of 50 per second.

Usefulness of contrast agents in the diagnosis of left ventricular pseudoaneurysm after acute myocardial infarction.

Abstract: Background and Objective: The diagnosis of left ventricular pseudoaneurysm after acute myocardial infarction is usually based on echocardiography. However, this technique may have limitations in some patients, especially in cases with suboptimal acoustic window. The objective of this study was to evaluate the usefulness of contrast echocardiography in the diagnosis of left ventricular pseudoaneurysm after myocardial infarction. Methods and Results: The study population comprises six patients in whom a two-dimensional echocardiography showed an image consistent with left ventricular pseudoaneurysm. Levovist® (Schering) 4 gr was administered i.v. to more clearly visualize the blood flow from the left ventricle to the left ventricular pseudoaneurysm cavity in all patients. Infarct location was anterior in five patients, and posterolateral in one. No patient had received thrombolysis or primary angioplasty during the acute phase. The transthoracic echocardiographic study showed an echo-free space adjacent to left ventricle in all patients. In four cases, the diagnosis of left ventricular pseudoaneurysm was made before contrast administration. In the remaining two patients, the definite diagnosis was made only after Levovist® administration. Conclusion: In the diagnosis of postinfarction left ventricular pseudoaneurysm, the administration of contrast agents may be of help in the correct visualization of the blood flow from the left ventricle to the left ventricular pseudoaneurysm cavity, and may allow a definite diagnosis to be obtained in some patients. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Left Atrial Appendage Function In Patients with Mitral Stenosis in Sinus Rhythm

Abstract: Aims: Left atrial appendage thrombi are believed to be the source of embolism in patients with rheumatic mitral stenosis in atrial fibrillation. There are a few studies which search the effects of left atrial appendage dysfunction in patients with mitral stenosis in sinus rhythm. Methods and Results: Left atrial appendage function and flow patterns in 41 patients with rheumatic mitral stenosis in sinus rhythm and 11 healthy subjects were studied by transoesophageal echocardiography. Left atrial appendage flow profiles were recorded within the proximal third of the appendage. The left atrial appendage ejection fraction was expressed as (maximal area of appendage minimal area of appendage)/maximal area of appendage. In addition, two-dimensional imaging was used to determine the presence of spontaneous echocardiographic contrast and thrombus formation. Patients with mitral stenosis in sinus rhythm had significantly decreased left atrial appendage emptying and filling velocities compared to controls (0·40±0·15 m/s vs 0·82±0·19 m/s and 0·42±0·21 m/s vs 0·68±0·28, respectively, P <0·001 and P <0·05). Compared with the control subjects, patients with mitral stenosis had significantly greater maximal area of the appendage and had reduced left atrial appendage ejection fraction (5·3±2·2 cm2 vs 2·4±0·5 cm2 and 50±16% vs 70±7%, respectively, P <0·001 and P <0·05). Of the patients with mitral stenosis in sinus rhythm, seven patients had spontaneous echocardiographic contrast and one of these had left atrial appendage thrombus. Compared with patients without spontaneous echocardiographic contrast, patients with spontaneous echocardiographic contrast had decreased left atrial appendage ejection fraction (33±21% vs 54±13%, P <0·01). One of the patients with mitral stenosis had central retinal artery occlusion, but thrombus was not observed in left atrial appendage. Conclusion: The study found that left atrial appendage dysfunction may occur in patients with mitral stenosis in sinus rhythm. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Left ventricular diastolic dysfunction in congenital chronic anaemias during childhood as determined by comprehensive echocardiographic imaging including acoustic quantification.

Abstract: Aims: To evaluate prospectively the left ventricular performance in thalassaemia major and sickle cell disease using comprehensive echocardiographic imaging including acoustic quantification during early childhood. Methods and Results: Twenty-three patients with thalassaemia and 26 patients with sickle cell disease underwent echocardiographic examination including M-mode, 2-D, Doppler and acoustic quantification. All patients were matched for age, sex, weight and height with 20 normal controls. All patients were below 13 years of age. Thalassaemia and sickle cell disease patients were significantly anaemic when compared with normals ( P <0.0001). All patients had normal left ventricular systolic parameters. Acoustic quantification-derived left ventricular volumes, filling rates, and emptying rates were not different in thalassaemia patients from controls. Left ventricular volumes, however, were larger in sickle cell disease patients than in controls. In contrast, by Doppler technique, left ventricular filling occurs mainly in early diastole (E wave) in thalassaemia patients and mainly in late diastole (A wave) in sickle cell disease patients, ( P =0.03 and 0.01 respectively). E/A ratio was lower and diastolic filling period was shorter than normal in sickle cell disease but not in thalassaemia patients. Patients in both groups had left ventricular mass (determined by M-mode) significantly higher than normal ( P <0.0001). Conclusion: The left ventricular systolic performance is well preserved in patients with chronic anaemia due to thalassaemia major and sickle cell disease during early childhood. In both diseases, however, there is left ventricular hypertrophy and measurable abnormalities in the diastolic filling detected by Doppler. Such changes do not fit a specific cardiomyopathic pattern due to diastolic dysfunction i.e. restrictive physiology vs delayed relaxation. Acoustic quantification of left ventricular diastolic parameters (filling rates) was less sensitive than Doppler in detecting these early diastolic abnormalities in both diseases. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Behcet's disease with a large and free right atrial thrombus.

Abstract: We present a case of a 27-year-old male patient with Behcet's disease who presented with dyspnoea and haemoptysis in whom further investigation revealed a large and free right atrial thrombus and pulmonary thromboembolism. Considering the absence of haemodynamic compromise and the risk of recurrence after surgical treatment for cardiac thrombus, we preferred medical management which consisted of immunosuppression and anticoagulation. On a follow-up period of 12 months we observed complete dissolution of the thrombus and dramatic improvement of clinical status.

Visualization of Left Atrial Appendage and Assessment of its Function by Transthoracic Second Harmonic Imaging and Contrast-Enhanced Pulsed Doppler

Abstract: Background: Low flow velocity within the left atrial appendage, as assessed by transoesophageal echocardiography, is a predictor of thromboembolism and of a low success rate of cardioversion of atrial fibrillation. However, the semi-invasive nature does limit its serial application as a screening technique. Methods and Results: We investigated the value of transthoracic second harmonic echocardiography and pulsed Doppler at baseline and after intravenous contrast injection to visualize the left atrial appendage and assess blood flow velocities within its cavity. We studied 51 consecutive patients undergoing transoesophageal echocardiography. After transoesophageal echocardiography, transthoracic second harmonic imaging was performed and the left atrial appendage was visualized in 46 patients. Interpretable pulsed Doppler tracings of left atrial appendage flow were obtained at baseline in 39 patients and in 45 patients during Levovist administration. The correlations between peak emptying velocity of left atrial appendage as measured by transoesophageal echocardiography and by transthoracic standard and contrast-enhanced Doppler were 0·81 and 0·91, respectively. The agreement between transoesophageal echocardiography and transthoracic contrast-enhanced pulsed Doppler echocardiography in classifying left atrial appendage flow velocity patterns was 93%. Left atrial appendage thrombus was detected by transthoracic second harmonic imaging in only one of the eight patients shown by transoesophageal echocardiography to have a thrombus. However, all but one of the patients with left atrial appendage thrombus and/or spontaneous echocardiographic contrast at transoesophageal echocardiography had <30 cm/s left atrial appendage flow velocity by transthoracic Doppler. Conclusions: This study shows that left atrial appendage can be visualized by transthoracic second harmonic imaging and that the flow velocity within its cavity is reliably measured by pulsed Doppler in a substantial fraction of patients. Contrast enhancement improves the feasibility and the accuracy of transthoracic evaluation of left atrial appendage flow velocity. The practical value of these results in predicting thromboembolic risk and success of cardioversion of atrial fibrillation needs to be proved by prospective studies.

Non-invasive Estimation of Left Ventricular Filling Pressures by Doppler Echocardiography

Abstract: Besides being complicated reality,in my experience, is odd . . ..Of course anyone can be simpleif he has no facts to bother aboutC. S. LewisHeart failure is haemodynamically characterized byelevated left ventricular filling pressure. Its determi-nation is important in order to optimize unloadingtherapy, interpret equivocal symptoms, predict prog-nosis and the follow-up of treatments

Lipomatus hypertrophy of the atrial septum and prominent crista terminalis appearing as a right atrial mass.

Abstract: In these case reports, transthoracic echocardiography suggested the presence of a right atrial mass. However, subsequent transoesophageal echocardiography revealed that the ‘right atrial mass’ was actually a lipomatous hypertrophied atrial septum in combination with a prominent crista terminalis. An understanding of the anatomy and the echocardiographic appearance of a lipomatous hypertrophied atrial septum appearing with a prominent crista terminalis will minimize the misdiagnosis of these structures. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Myocardial contrast echocardiography yields best accuracy using quantitative analysis of digital data from pulse inversion technique: comparison with second harmonic imaging and harmonic power Doppler during simultaneous dipyridamole stress SPECT studies.

Abstract: Aims: This prospective study assesses the (1) feasibility of quantifying ultrasound myocardial perfusion studies based on the densitometric analysis of digital data and the (2) comparison of pulse inversion, second harmonic and harmonic power Doppler modalities with SPECT. Methods and Results: Twenty-three patients with suspected ischaemic heart disease had i.v. injections of TcSestamibi and Optison during a dipyridamole stress test for echocardiography in pulse inversion, second harmonic and harmonic power Doppler mode. Analysis was (a) visual by scoring and (b) quantitative by densitometry of digital data for background subtracted myocardial opacification (a.u.) and normalized contrast effect (%). In the nine control patients, myocardial opacification at stress was greater (P0·002) than in the pathologic group (5·83·3 vs 2·62·5 a.u. in pulse inversion, 5·42·1 vs 2·41·8 in second harmonic and 7·13·7 vs 4·93·7 a.u. in harmonic power Doppler). In the pathologic group, normalized contrast effect decreased significantly during stress (23·718·8 to 11·310·8%, P<0·003) only in pulse inversion. Kappa values for patient based diagnostic agreement with SPECT were 0·75 by pulse inversion, 0·62 by second harmonic and 0·52 by harmonic power Doppler for quantitative analysis, and 0·51, 0·37 and 0·35 respectively, for visual assessment.

The principle of multidimensional arrays.

Abstract: Echocardiography is one of the most important diagnostic tools in cardiology today. One-dimensional phased arrays have been used extensively because they have a small footprint and allow beam steering. Their major limitation lies in that these devices can only be used to acquire images of two-dimensional slices in real-time and that the slice thickness cannot be controlled. To allow real-time three-dimensional imaging of the heart and focusing of the ultrasonic beam in two-dimensional, two-dimensional arrays, the design and fabrication of which are enormous engineering challenges, are required. Before reaching this ultimate goal, limited focusing in the elevational plane can be achieved with 1·5-dimensional arrays. Focusing in the elevational plane allows a reduction in slice thickness and thus an improvement in the image quality over a larger depth of view. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Assessment of the left atrial appendage mechanical function by three-dimensional echocardiography.

Abstract: Aims: We evaluated the feasibility of three-dimensional echocardiography, in the assessment of left atrial appendage (LAA) function. Methods and Results: Forty-five patients underwent multiplane transoesophageal echocardiography. In addition to Doppler and two-dimensional echocardiography, data for three-dimensional echocardiography reconstruction were obtained during transoesophageal echocardiography. Left atrial appendage ejection fraction based on three-dimensional echocardiography volume measurements (EFv) and two-dimensional echocardiography area measurements (EFa), coupled with other echocardiographic data, were related to left atrial appendage late peak emptying velocity, a frequently used indicator of left atrial appendage function. Multiple regression analysis has revealed a significant association of peak emptying velocity with EFv ( P <0·0001), spontaneous echocardiographic contrast ( P =0·001), tricuspid regurgitation ( P =0·03) and left ventricular hypertrophy ( P =0·05). No significant relation was observed between peak emptying velocity and EFa, presence or absence of atrial fibrillation, left ventricular dysfunction, mitral stenosis and insufficiency, left atrial dilatation, pulmonary venous peak systolic, diastolic and peak reverse flow velocity at atrial contraction as well as left atrial appendage volumes derived from two-dimensional echocardiography and three-dimensional echocardiography. In a simple linear correlation, the degree of association between peak emptying velocity and EFv was higher as between peak emptying velocity and EFa (r=0·7 vs 0·4, both P <0·001). Observer variabilities for calculating EFv were considerably lower than for two-dimensional echocardiography derived EFa. Ejection fractions determined by two-dimensional echocardiography area measurements at 45°, 90° and 135° cutplane angulations were related to EFv only at 135°. Conclusions: Left atrial appendage ejection fraction calculation by three-dimensional echocardiography is feasible, more accurate than by two-dimensional echocardiography and has lower observer variability. Furthermore, an optimal cutplane angulation of the left atrial appendage view at 135° has been demonstrated. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Non-compaction cardiomyopathy-echocardiographic diagnosis.

Abstract: Non-compaction cardiomyopathy is a recently recognized disorder caused by a defect in endomyocardial morphogenesis. The disease can present with heart failure, systemic embolic events, and ventricular arrhythmias. Long-term prognosis is poor. Echocardiography is used to confirm the diagnosis; in the current case-report, we describe the typical abnormalities observed on echocardiography in a patient with non-compaction cardiomyopathy. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Quantitative techniques for stress echocardiography: Dream or reality?

Abstract: Stress echocardiography is now an everyday clinical tool. However, the substantial evidence base that supports its use is largely derived from expert centres, and concerns have been expressed about the performance of the test in less expert hands. A unifying feature of the problems of stress echocardiography is its subjective assessment. This review examines the consequences of qualitative interpretation and the benefits of developing a quantitative approach. Although no quantitative approach is in widespread clinical use, several alternative techniques are feasible, and this area warrants further study.

Real Time Contrast Echocardiography — A New Bedside Technique to Predict Contractile Reserve Early After Acute Myocardial Infarction

Abstract: Aims: Power pulse inversion echocardiography is a new technique by which contrast microbubbles can be visualised in real time within the myocardium, enabling simultaneous assessment of myocardial function and microvascular integrity, which is a prerequisite for myocardial viability. We aimed to determine whether microvascular integrity using power pulse inversion can be used to predict contractile reserve early after myocardial infarction. Methods and Results: We studied 19 stable patients 5·1(1·6) days after presentation using low dose dobutamine stress echocardiography and power pulse inversion using slow bolus intravenous injections of Optison. A 16-segment left ventricular model was used to define wall thickening at baseline and following low dose dobutamine infusion (1, normal; 2, reduced; 3, absent), and contrast opacification (1, homogeneous; 2, heterogenous or reduced; 3, absent). The techniques were compared on a segment-by-segment basis to determine whether microvascular integrity (contrast opacification score of 1 or 2) could predict contractile reserve (any improvement during low dose dobutamine infusion) in segments that were akinetic at rest. Follow-up echocardiography was performed one month later. Results: Ninety-four (31%) of the 304 segments were akinetic at rest, and 22 (23%) of these demonstrated contractile reserve. In 87 (92%) of the resting akinetic segments contrast opacification could be adequately determined, and of these 20 (23%) showed microvascular integrity. The negative and positive predictive value of microvascular integrity for determining contractile reserve was 90% and 65%, respectively, and 92% and 59% respectively for predicting recovery of function. Conclusion: Power pulse inversion can be used at rest to determine myocardial function and simultaneously to predict contractile reserve of akinetic segments in patients early after myocardial infarction. This technique has the potential to provide a bedside assessment of myocardial viability.

Striking effect of left ventricular high filling pressure with mitral regurgitation on mitral annular velocity during early diastole. A study using colour M-mode tissue Doppler imaging.

Abstract: Aims: To evaluate the effect of considerably high left ventricular filling pressure with mitral regurgitation on mitral annular velocity during early diastole. Subjects: Two hundred and forty-three patients who underwent cardiac catheterization for evaluation of chest pain. Methods: Mitral annular velocity during early diastole was measured by colour M-mode tissue Doppler imaging. Patients were divided into the following three groups according to the cardiac catheterization data. Group A (n=147): patients having left ventricular relaxation time constant τ<46 ms and left ventricular end-systolic volume index <38 ml m−2; group B (n=88): patients having τ≥46 ms and/or end-systolic volume index ≥38 ml m−2; group C (n=8): patients having mean pulmonary capillary wedge pressure ≥16 mmHg in addition to τ≥46 ms and end-systolic volume index ≥38 ml m−2. Results: Mitral annular velocity during early diastole was significantly less in group B (4·8±1·4 cm s−1) than in group A (7·7±1·9 cm s−1). However, there was no significant difference between groups A and C (8·3±0·8 cm s−1). A transmitral E/A >1·0 was observed in 12/147 patients of group A, 10/88 of group B, and 8/8 of group C. The incidence of ≥Sellers' grade II mitral regurgitation was higher in group C than the others. Conclusions: A paradoxically faster mitral annular velocity during early diastole is found in patients having left ventricular dysfunction with moderate to severe mitral regurgitation and considerably high left ventricular filling pressure. Attention should be paid to an interpretation of mitral annular velocity during early diastole regarding left ventricular early diastolic performance in patients having mitral regurgitation with an E/A >1·0 in their transmitral flow. Copyright 2002 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved .

Surface integration of velocity vectors from 3D digital colour Doppler: an angle independent method for laminar flow measurements.

Abstract: Background: The study was designed to test the angle independence of a dynamic three-dimensional digital colour Doppler method for laminar flow measurement. The technique acquired three-dimensional data by rotational acquisition and used surface integration of Doppler vector velocities and flow areas in time and space for flow computation. Method: A series of pulsatile flows (peak flow 55–180 ml/s) through a curved tube were studied with reference flow rates obtained using an ultrasonic flow meter. Colour Doppler imaging was performed at three angles to the direction of flow (20°, 30°, 40°), using a multiplane transoesophageal probe controlled by an ATL HDI 5000 system. Integration of digital velocity vectors over a curved three-dimensional surface across the tube for each of the 11 flow rates at each angle was performed off-line to compute peak flow. Results: Peak flow rates correlated closely (r=0·99) with the flow meter with the mean difference from the reference being −0·8±2·4 ml/s, 0·9±2·6 ml/s, 1·0±2·3 ml/s for 20°, 30° and 40° respectively. Comparison of the three angle groups showed no significant differences ( P =0·15, ANOVA). When sampled obliquely, the flow area on the curved surface increased while the velocities measured decreased. Conclusion: Surface integration of velocity vectors to compute three-dimensional Doppler flow data is less angle dependent than conventional Doppler methods.

Protruding atherosclerotic aortic plaques and dyslipidaemia: correlation to subtypes of ischaemic stroke.

Abstract: AIMS To evaluate whether thoracic aortic plaques together with dyslipidaemia are related to ischaemic stroke, and if so, to which of the subtypes of stroke. METHODS AND RESULTS We performed transoesophageal echocardiography in 50 patients with acute ischaemic stroke and in 401 controls. The aorta was divided into two segments: (1) the proximal, proximal to the left subclavian artery, and (2) the distal aorta. Protruding plaques (Intima > or =4 mm in thickness) in the proximal aorta were detected in 14 of the 50 patients (28%) with stroke, and in 53 of the 401 controls (13%) (P<0.01). Plaque score in the proximal aorta (2.1 +/- 1.8 vs 0.9 +/- 0.7; P<0.05), low-density lipoprotein cholesterol level (3.60 +/- 0.85 vs 2.87 +/- 0.72 mmol/l; P<0.05), and apolipoprotein B/A-I ratio (0.98 +/-0.17 vs 0.73 +/- 0.16; P<0.005) were higher in patients with athero-thrombotic than in cardioembolic stroke. The score in the proximal aorta correlated with low-density lipoprotein cholesterol level (r=0.44, P<0.005) and apolipoprotein B/A-I ratio (r=0.40, P<0.01). CONCLUSION Severe plaques in the proximal aorta together with dyslipidaemia are seen more frequently in patients with atherothrombotic stroke. Lipid analysis may contribute to the prediction and the treatment of the patients who are at high risk for atherothrombotic stroke.

Coronary microcirculation in essential hypertension: a quantitative myocardial contrast echocardiographic approach

Abstract: Aims: The aims of the present study were: (a) to demonstrate whether quantitative myocardial contrast echocardiography can detect the increase in coronary flow induced by dipyridamole infusion vasodilation through the myocardial opacification due to the transit of microbubbles, both at rest and after dipyridamole induced vasodilation; (b) to explore the coronary microcirculatory function before and after dipyridamole in two different models: asymptomatic and relatively young hypertensive patients with a mild degree of left ventricular hypertrophy, and healthy controls. Methods and Results: Two groups of strictly agematched males were studied (case-control study): 10, relatively young and asymptomatic essential hypertensive patients with a mild degree of left ventricular hypertrophy with a normal left ventricular function, and 10 healthy controls. The main findings were: the microbubbles’ appearance area was significantly lower in hypertensive patients than in controls (P<0·05) because of a significantly lower time to peak. The peak intensity at rest was higher in hypertensives than in controls (P<0·05); but the per cent increase after vasodilatory stimulus was significantly higher in controls (+71% in controls vs +31% in hypertensives; P<0·05). The microbubbles’ disappearance area was comparable in both groups at rest; the per cent increase of this parameter after dipyridamole was significantly higher in controls (+124%) than in hypertensives (+90%) (P<0·05). The results achieved in this study documented that the coronary microcirculation in hypertensive patients presenting a mild degree of left ventricular hypertrophy, explored with quantitative myocardial contrast echocardiography, showed a different behaviour in comparison with controls, in the vasodilatory response to dipyridamole. Conclusion: The coronary microcirculation in hypertensives showed a reduced vasodilation capacity of the resistance arterioles under dipyridamole induced vasodilatation, and a possible impairment of the endothelium dependent vasodilation. This happened despite an increase in the left ventricular mass, where the relation between capillary bed distribution and hypertrophied myocardium (rarefaction phenomenon) is not completely respected.