[Echocardiographic assessment of myocardial function during His bundle and right ventricular pacing]. / Echokardiographische Beurteilung der myokardialen Funktion unter His-Bündel- und rechtsventrikulärer Schrittmacherstimulation.

INTRODUCTION: In patients with pacemaker (PM) therapy, His bundle stimulation (HBS) may lead to a more synchronous activation of the left ventricle (LV) than conventional right ventricular stimulation (RVS). In this study, we investigated to which extent this effect can be objectified by means of contemporary echocardiographic functional imaging. METHODS: In all, 15 RVS patients (6 women, mean age 76.6 ± 4.1 years) and 15 HBS patients (6 women, mean age 74.6 ± 3.7 years) underwent echocardiography with and without cardiac pacing. Besides LV end-diastolic volume (EDV), ejection fraction (EF), and global strain (GLS), we measured global and regional myocardial work and LV efficiency based on noninvasive pressure-strain loops. RESULTS: In all HBS patients, optimization of PM settings resulted in immediate changes in myocardial function parameters. With pacing, RVS patients showed a higher decrease in EF and GLS than HBS patients. Global LV work and LV work efficiency decreased significantly only in RVS patients. CONCLUSION: Changes in regional and global myocardial function can by proven and quantified by functional echocardiography. In patients under PM therapy, HBS shows functional advantages in comparison to conventional RVS.

Left atrial chamber and appendage function after internal atrial defibrillation: a prospective and serial transesophageal echocardiographic study.

OBJECTIVES: The purpose of this prospective study was to assess left atrial chamber and appendage function after internal atrial defibrillation of atrial fibrillation and to evaluate the time course of recovery. BACKGROUND: External cardioversion of atrial fibrillation may result in left atrial appendage dysfunction ("stunning") and may promote thrombus formation. In contrast to external cardioversion, internal atrial defibrillation utilizes lower energies; however, it is unknown whether the use of lower energies may avoid stunning of the left atrial appendage. METHODS: Transesophageal and transthoracic echocardiography were performed in 20 patients 24 h before and 1 and 7 days after internal atrial defibrillation to assess both left atrial chamber and appendage function. Transthoracic echocardiography was again performed 28 days after internal atrial defibrillation to assess left atrial function. The incidence and degree of spontaneous echo contrast accumulation (range 1+ to 4+) was noted, and peak emptying velocities of the left atrial appendage were measured before and after internal atrial defibrillation. To determine left atrial mechanical function, peak A wave velocities were obtained from transmitral flow velocity profiles. RESULTS: Sinus rhythm was restored in all patients. The mean +/- SD peak A wave velocities increased gradually after cardioversion, from 0.47 +/- 0.16 m/s at 24 h to 0.61 +/- 0.13 m/s after 7 days (p < 0.05) and 0.63 +/- 0.13 m/s after 4 weeks. Peak emptying velocities of the left atrial appendage were 0.37 +/- 0.16 m/s before internal atrial defibrillation, decreased significantly after internal atrial defibrillation to 0.23 +/- 0.1 m/s at 24 h (p < 0.01) and then recovered to 0.49 +/- 0.23 m/s (p < 0.01) after 7 days. The corresponding values for the degree of spontaneous echo contrast were 1.2 +/- 1.2 before internal atrial defibrillation versus 2.0 +/- 1.0 (p < 0.01) and 1.1 +/- 1.3 (p < 0.01) 1 and 7 days after cardioversion, respectively. One patient developed a new thrombus in the left atrial appendage, and another had a thromboembolic event after internal atrial defibrillation. CONCLUSIONS: Internal atrial defibrillation causes depressed left atrial chamber and appendage function and may result in the subacute accumulation of spontaneous echo contrast and development of new thrombi after cardioversion. These findings have important clinical implications for anticoagulation therapy before and after low energy internal atrial defibrillation in patients with atrial fibrillation.

Multiplane transesophageal echocardiographic assessment of mitral regurgitation by Doppler color flow mapping of the vena contracta.

Assessment of the severity of mitral regurgitation (MR) by Doppler color flow mapping is limited by dependence of jet area on hemodynamic and technical variables. The width of the MR jet at its origin may be less dependent on hemodynamic variables, and thus should more accurately reflect the severity of MR. Doppler color flow mapping was performed in 80 subjects by transesophageal echocardiography (TEE) within 48 hours of catheterization. Width of the MR jet at its vena contracta was measured by both single plane and multiplane TEE and compared with the angiographic grade of MR and regurgitant volume. The width of the MR jet correlated closely with angiographic grade by both methods. A jet width > or = 6 mm identified angiographically severe MR with a sensitivity and specificity of 100% and 83% by single-plane TEE, and 95% and 98% by multiplane TEE. The sensitivity and specificity for detecting a regurgitant volume > or = 80 ml was 93% and 76% for single-plane TEE, and 86% and 95% for multiplane TEE. Thus, the width of the MR jet at its vena contracta by Doppler color flow mapping is an accurate marker of the severity of MR. By virtue of its ability to obtain orthogonal views specifically oriented to mitral leaflet coaptation, multiplane TEE is superior to single-plane TEE in assessing MR jet width.

Color-coded Doppler imaging of the vena contracta as a basis for quantification of pure mitral regurgitation.

The narrowest central flow region of a jet is defined as the vena contracta. This term is applied also to the contracted zone of the Doppler color flow image of a jet at its passage through an incompetent mitral valve. The clinical applicability of measuring the size of the vena contracta by transthoracic color-coded Doppler echocardiography for estimating the severity of mitral regurgitation (MR) was evaluated. In 78 of 82 patients with angiographically proved MR, a coherent flow image across the valve was visualized. The maximal diameter in the apical long-axis view was considered as a representative value for the size of the vena contracta. In comparison with the maximal left atrial velocity pixel area, this parameter revealed higher correlations to the angiographic degree of MR and to the regurgitant volume (r = 0.94 vs 0.72, and 0.83 vs 0.71, respectively). The highest positive and negative predictive accuracies for differentiating mild-to-moderate from severe MR were determined for a diameter of 6.5 mm (88 and 96%, respectively). Because the vena contracta is directly related to the severity of MR, it is concluded that it is helpful to use this parameter instead of the maximal velocity pixel area for semiquantitative grading.

Relation between symptoms and profiles of coronary artery blood flow velocities in patients with aortic valve stenosis: a study using transoesophageal Doppler echocardiography.

OBJECTIVE: To analyse profiles of coronary artery flow velocity at rest in patients with aortic stenosis and to determine whether changes of the coronary artery flow velocities are related to symptoms in patients with aortic stenosis. DESIGN: A prospective study investigating the significance of aortic valve area, pressure gradient across the aortic valve, systolic left ventricular wall stress index, ejection fraction, and left ventricular mass index in the coronary flow velocity profile of aortic stenosis; and comparing flow velocity profiles between symptomatic and asymptomatic patients with aortic stenosis using transoesophageal Doppler echocardiography to obtain coronary artery flow velocities of the left anterior descending coronary artery. SETTING: Tertiary referral cardiac centre. PATIENTS: Fifty eight patients with aortic stenosis and 15 controls with normal coronary arteries. RESULTS: Adequate recordings of the profile of coronary artery flow velocities were obtained in 46 patients (79%). Left ventricular wall stress was the only significant haemodynamic variable for determining peak systolic velocity (r = -0.83, F = 88.5, P < 0.001). The pressure gradient across the aortic valve was the only contributor for explaining peak diastolic velocity (r = 0.56, F = 20.9, P < 0.001). Controls and asymptomatic patients with aortic stenosis (n = 12) did not differ for peak systolic velocity [32.8 (SEM 9.7) v 27.0 (8.7) cm/s, NS] and peak diastolic velocity [58.3 (18.7) v 61.9 (13.5) cm/s, NS]. In contrast, patients with angina (n = 12) or syncope (n = 8) had lower peak systolic velocities and higher peak diastolic velocities than asymptomatic patients (P < 0.01). Peak systolic and diastolic velocities were -7.7 (22.5) cm/s and 81.7 (17.6) cm/s for patients with angina, and -19.5 (22.3) cm/s and 94.0 (20.9) cm/s for patients with syncope. Asymptomatic patients and patients with dyspnoea (n = 14) did not differ. CONCLUSIONS: Increased pressure gradient across the aortic valve and enhanced systolic wall stress result in characteristic changes of the profile of coronary flow velocities in patients with aortic stenosis. Decreased or reversed systolic flow velocities are compensated by enhanced diastolic flow velocities, particularly in patients with angina and syncope. This characteristic pattern of the profile of coronary artery flow velocities in patients with angina or syncope may be useful for differentiating those patients from asymptomatic patients.

Morphology of the mitral valve as displayed by multiplane transesophageal echocardiography.

This study was performed to (1) describe how multiplane transesophageal echocardiography (TEE) facilitates imaging of the entire mitral valve apparatus, and (2) prospectively compare the morphology of the different segments of the mitral apparatus as determined by multiplane TEE and direct surgical inspection. The study consisted of 30 consecutive patients examined by multiplane TEE less than 24 hours before mitral valve surgery. The mitral valve was displayed in transgastric and transesophageal views with the imaging planes specifically aligned to demonstrate continuity between the papillary muscles, chordae tendineae, and leaflet edges. The character and location of morphologic abnormalities identified by findings of preoperative TEE were highly concordant with surgical inspection of the valve (p < 0.0001). Thus multiplane TEE offers the ability to visualize the entire mitral apparatus as a functional unit and to identify morphologic abnormalities of the valve correctly.

A simplified, practical echocardiographic approach for 3-dimensional surfacing and quantitation of the left ventricle: clinical application in patients with abnormally shaped hearts.

The goal of this study was to validate the quantitative accuracy of a system for 3-dimensional (3D) echocardiographic reconstruction of the left ventricle to assess its volume and function in human beings by using 3 apical views as a simplified technique to promote practical clinical application. End-diastolic and end-systolic volumes (EDV, ESV) and ejection fraction (EF) were obtained by 3D echocardiography in 50 patients with dilated or geometrically distorted left ventricles and compared with values from magnetic resonance imaging (20 consecutive patients), angiography (22 consecutive patients), and radionuclide imaging (8 consecutive patients). Three-dimensional results were also compared with 2-dimensional (2D) echocardiographic estimates. Three-dimensional left ventricular reconstruction provided values that correlated and agreed well with pooled data from the other techniques for EDV (y = 0.93x + 9.1, r = 0.95, standard error of the estimate [SEE] = 15.2 mL, mean difference = -0.5 +/- 15.4 mL), ESV (y = 0.94x + 4.3, r = 0. 96, SEE = 11.4 mL, mean difference = 0.4 +/- 11.5 mL), and EF (y = 0. 90x + 4.1, r = 0.92, SEE = 6.2%, mean difference = -0.9 +/- 6.4%) (all mean differences not significant versus 0), with greater errors by 2D echocardiography. Intraobserver and interobserver variabilities of 3D echocardiography were less than 6% for EDV, ESV, and EF. The overall time for image acquisition and 3D reconstruction was 5 to 8 minutes. Although this 3D method uses only a small number of apical views, it accurately calculates EDV, ESV, and EF in patients with dilated and asymmetric left ventricles and is more accurate than 2D echocardiography. The flexible surface fit used to combine the 3 views provides a convenient visual output as well as quantitation. This simple and rapid 3D method has the potential to facilitate routine clinical applications that assess left ventricular function and changes that occur with remodeling.

Semiquantitation of aortic regurgitation by pulsed Doppler examination of the subclavian artery velocity contour.

The reflux of aortic regurgitation causes an increased and longer diastolic reverse flow in the aorta and its branching vessels as compared to the normal flow contour. The changes of the aortic flow are related to the severity of aortic regurgitation and can be demonstrated by Doppler ultrasound. As Doppler examinations are often restricted in the aorta, a prospective study was designed to determine the feasibility and accuracy of Doppler measurements in the subclavian artery for the identification of severe forms of aortic regurgitation. Fifty-five patients with and 40 patients without aortic regurgitation were examined both by aortography and pulsed Doppler flow analysis of the subclavian artery. Two age groups were differentiated: patients below and those over 60 years of age, respectively. A high quality Doppler signal was recorded in all patients. In patients below 60 years, the best predictors of severe aortic regurgitation proved to be a pandiastolic reverse flow and an increased regurgitant fraction (77%) with a sensitivity of 100% and specificity of 75% and 92%, respectively. Since a pandiastolic reverse flow was detected in most patients in the control group over 60 years, it was not indicative of aortic regurgitation in these cases. However, an increased maximal diastolic velocity (> -37 cm/s) identified severe forms of aortic regurgitation in this age group with a sensitivity of 89% and a specificity of 100%. Therefore, severe forms of aortic regurgitation may be reliably identified by analysing the subclavian artery Doppler spectrum. In conclusion, the method is a useful adjunctive technique to other Doppler echocardiographic methods to assess the severity of aortic regurgitation.

Paraprosthetic regurgitation in aortic prostheses: determination of the hemodynamic significance by pulsed Doppler examination of the subclavian artery flow.

Paraprosthetic leaks in aortic prostheses may cause significant aortic regurgitation. Color flow Doppler echocardiography is the method of choice for detecting paraprosthetic leaks, but quantitation of regurgitation is limited by this method. This study investigated the value of pulsed Doppler of the left subclavian artery flow for assessing the hemodynamic significance of paraprosthetic regurgitation in aortic prostheses in 32 patients with, and in 77 control subjects without paraprosthetic leaks. Paraprosthetic leaks were either detected by transthoracic or transesophageal color flow echocardiography. The hemodynamic significance of paraprosthetic regurgitation was determined by means of a dichotomous angiographic classification - significant versus insignificant regurgitation. Pulsed Doppler was performed to measure the maximal diastolic and systolic velocities, and diastolic and systolic velocity-time-integrals (VTI) and their ratios in the subclavian artery flow. The accuracy of these parameters for differentiating significant versus insignificant regurgitation was assessed. Angiography revealed 13 significant and 19 insignificant forms of aortic regurgitation. In all patients, examination of the subclavian artery was feasible by pulsed Doppler. The highest correlation between Doppler derived parameters and regurgitation was calculated for the ratios of diastolic and systolic VTI (r = 0.84), diastolic VTI (r = 0.82) and ratio of diastolic and systolic velocities (r = 0.80). An increase of the ratio of diastolic and systolic VTI (> 45%) and ratio of diastolic to systolic velocity (> 0.4), and increased diastolic VTI (> 60 cm) in the subclavian artery velocity profile identified significant paraprosthetic regurgitation with a sensitivity of 94%, 75% and 87%, and specificity of 87%, 80% and 87%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic profile of the normally functioning Omnicarbon valve.

Transthoracic echocardiography was performed in 141 patients with 90 Omnicarbon valves in the aortic and 66 in the mitral position. Additionally, 53 of them were investigated by transesophageal echocardiography comparing monoplane and multiplane facilities. The opening direction of the disc and the location of the pivot axis could be correctly determined by transthoracic, monoplane, and multiplane transesophageal echocardiography, respectively, in 100%, 80%, and 100% of the mitral and in 53%, 21%, and 82% of the aortic prostheses. Small regurgitation jets were detected in 90% of the aortic valves (1.6 +/- 0.4 cm2) by transthoracic and in all mitral prostheses (2.3 +/- 0.8 cm2) by transesophageal echocardiography. Based on morphological identification of the pivot points structures, origins of leakage jets were clearly identified as "design-related" in 12% (transthoracic echocardiography of aortic valves) to 100% (multiplane transesophageal echocardiography of mitral valves). In the aortic position, values obtained for transprosthetic forward flow velocity measurements exhibited wide scatter which did not allow a firm separation between valve sizes. No better differentiation was possible by using the calculated Doppler gradients or the velocity time integrals, either. Mean gradients and velocity time integrals showed even smaller differences between groups in the mitral valve patients. It is concluded that the Omnicarbon valve has a suitable design for morphological echocardiographic examination, and multiplane transesophageal technique expands the diagnostic capability. Forward flow measurements do not appear to be suited for detecting a beginning obstruction of this mechanical prosthesis.

Valvular aortic stenosis: risk of syncope.

BACKGROUND AND AIMS: Syncope is a serious complication of aortic stenosis. The aim of this study was to determine whether hemodynamic parameters are useful for estimating the risk of syncope in aortic stenosis. METHODS: In 43 patients with aortic stenosis, cardiac catheterization and echocardiography were performed to measure the pressure gradient across the aortic valve, the aortic valve area, left ventricular mass index, systolic left ventricular wall stress and peak systolic coronary artery flow velocities. Hemodynamic parameters were correlated with syncope and the accuracy of those parameters for determining the risk of syncope were assessed. RESULTS: Ten out of 43 patients experienced syncope. The highest correlation with syncope was found for systolic left ventricular wall stress (R = 0.74, p < 0.001). In descending order of correlation were peak systolic coronary artery flow velocity (R = 0.68, p = 0.002), the pressure gradient across the aortic valve (R = 0.62, p = 0.01) and the aortic valve area (R = 0.43, p = 0.03). Left ventricular mass index was not significantly correlated with syncope. Multivariate analysis revealed systolic left ventricular wall stress to be the only factor contributing to determining syncope (F-to-remove: 47.8). A discriminative value of > 225 dyn/cm-2 x 103 for left ventricular wall stress identified patients with a history of syncope with a specificity of 97% and a sensitivity of 90%. CONCLUSIONS: Syncope in aortic stenosis is closely correlated to increased left ventricular wall stress and attenuated, peak systolic coronary flow velocities. Cut off values may be used to identify patients with an increased risk of syncope.

Doppler echocardiographic study of pulmonary venous flow in mitral stenosis and early after mitral valve replacement.

The aim of the study was Doppler echocardiographic assessment of the effect of mitral stenosis (MS) on pulmonary venous flow (PVF), and of any changes occurring after mitral valve replacement. Fifty patients with MS (22 in atrial fibrillation (AF)) and 28 healthy subjects (control group) underwent transthoracic echocardiographic evaluation of PVF. Fourteen of the 22 patients in AF were submitted in addition to transesophageal echo study before and after mitral valve replacement. Pulmonary wedge pressure was measured in 18 patients. Patients in sinus rhythm (SR) and more than mild MS showed significantly decreased peak velocity and flow velocity time integral of the systolic forward PVF. This finding was more exaggerated in MS with AF. Concerning diastolic forward PVF, patients in SR showed significantly decreased peak velocity and velocity time integral, irrelevant of the degree of MS, while patients with AF exhibited adequate signs of flow. In all patients duration, deceleration time (D-DT) and pressure half-time (D-PHT) of the diastolic forward PVF were significantly increased. The last two parameters correlated with the corresponding variables of mitral flow and with echocardiographically determined mitral valve area and the D-DT of the pulmonary wedge pressure. Concerning reversed PVF, patients with more than mild MS exhibited significantly increased peak velocity and velocity time integral. After mitral valve replacement, a significant increase of diastolic forward peak velocity and velocity time of the PVF were detected. The duration of diastolic forward peak velocity of PVF, D-DT and D-PHT decreased. The systolic forward phase did not change significntly after the valve replacement.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis and follow-up of congenital heart disease in children with the use of two-dimensional Doppler echocardiography.

Two-dimensional echocardiography (2D) represents a major advance in non-invasive diagnosis of congenital heart disease (CHD) in children. Nevertheless it has diagnostic limitations in nearly all kinds of heart lesions. These can be overcome for the most part by integration of a pulsed Doppler system. This may be called two-dimensional Doppler echocardiography (2DD). Hereby blood flow information is added to the 2D image. Some common types of CHD including ventricular and atrial septal defects, persistent ductus arteriosus, pulmonic stenosis and coarctation are described with their typical 2DD findings. Non-invasive follow up of children with CHD and early recognition of typical complications can be achieved reliably using 2DD. Future prospects consist in a more quantitative diagnostic application of 2DD.

[Diagnosis and treatment of pericardial effusions with the aid of 2-dimensional Doppler echo cardiography (author's transl)]. / Diagnostik und Therapie des Perikardergusses mit Hilfe der zweidimensionalen Dopplerechokardiographie.

In a case of a large acute pericardial effusion the diagnosis and the following pericardiocentesis under visible control by means of 2-dimensional echocardiography (2 D-E) are described. The effusion coat around the heart can clearly be localised. Furthermore, a new echocardiographic system is used combining 2 D-E and range-gated pulsed Doppler technique that allows the registration of flow-velocity curves in the superior vena cava and the recognition of a beginning cardiac tamponade. If indicated, the following pericardiocentesis can be done under direct ultrasonic control avoiding any risk of heart perforation.

[Spiral computerized tomography, multiplane transesophageal echocardiography and magnetic resonance imaging in the diagnosis of thoracic aortic dissection]. / Spiral-Computertomographie, multiplane transösophageale Echokardiographie und Magnetresonanztomographie in der Diagnostik thorakaler Aortendissektionen.

The aim of this study was the evaluation of spiral computed tomography (Spiral-CT), multiplane transesophageal echocardiography (multiplane TEE) and magnetic resonance imaging (MRI) in the diagnosis of thoracic aortic dissection. 41 patients were examined: 30 with clinically suspected acute aortic dissection (14 Stanford A, 7 Stanford B), 11 with aortic repair (7/11 with persisting distal dissection). In 14 patients there was involvement of the supraaortic vessels. Sensitivity of Spiral-CT, multiplane TEE and MRI in the detection of aortic dissection was 100%, specificity was 100, 92, and 91%. In the assessment of involvement of aortic arch vessels sensitivity was 100, 67, and 60%, specificity was 100, 95, and 90%. The new imaging modalities Spiral-CT and multiplane TEE are equal to MRI in the detection of aortic dissection. In the assessment of the supraaortic branches Spiral-CT is superior to multiplane TEE and MRI and might become the method of choice.

Left systolic atrioventricular plane displacement in the assessment of myocardial viability in patients with previous myocardial infarction.

UNLABELLED: In order to detect myocardial viability in coronary artery disease patients (CAD) with a previous myocardial infarction and dysfunction of the left ventricle (LV), the reliability of the left atrioventricular plane displacement (LAVPD) during low dose dobutamine stress echocardiography (DSE), was validated. The study population consisted of 70 CAD patients and 35 age and sex matched healthy subjects. From the apical four and two chamber views the LAVPD was recorded and measured by M-mode echocardiography, at four sites corresponding to the septal, lateral, anterior and inferior walls of the LV, prior and during the DSE (5-10 micrograms/kg/min). All patients underwent exercise SPECT Thallium-201 with four-hour redistribution and rest-reinjection, in order to determine tissue viability. Intraobserver and interobserver variability for the LAVPD was insignificant (5.8% and 7.2%, respectively). Healthy subjects exhibited a significant and equally distributed maximal increase of the LAVPD, at all sites during dobutamine infusion (DI) (p < 0.001). Patients also, showed a significant maximal increase of the LAVPD during DI, at all asynergic sites in which viable tissue was found (p < 0.001). However, in the asynergic sites without viable tissue the LAVPD did not significantly change (p < 0.05). Selecting a LAVPD increase of > 2 mm to detect viable myocardium at any asynergic site of LV, resulted in a sensitivity of 91% and specificity of 89%. When DSE was used for the detection of viable myocardium, sensitivity and specificity were found to be 80% and 87% respectively. The proportion of agreement between the two above mentioned methods was 82%. When the two methods were in agreement, the positive and negative predictive values were 94% and 97%, respectively. The validity of the above mentioned increase of the LAVPD was also prospectively examined in a similar group of 35 CAD patients exhibiting myocardial dysfunction as a result of a previous myocardial infarction (sensitivity 85% and specificity 90%, respectively). CONCLUSIONS: 1) The assessment of left LAVPD during DI is a new quantitative, accurate method with a low intraobserver and interobserver variability, in detecting viable myocardium. 2) Combination of this method and DSE proved good diagnostic markers of myocardial viability.

[Patient with heparin-induced thrombocytopenia type II and implanted left ventricular assist device]. / Patient mit heparininduzierter Thrombozytopenie Typ II und implantiertem linksventrikulärem Assistdevice.

The administration of heparin can lead to life-threatening heparin-induced thrombocytopenia (HIT) type II, which is caused by antibodies against heparin-platelet factor 4-complexes. The multimorbid patient presented here suffered from HIT II. Preoperative and postoperative prevention of thrombosis was successfully conducted with argatroban and the management of anticoagulation is presented. During therapy with argatroban, discrepancies in the partial thromboplastin time (PTT) and the international normalized ratio (INR) appeared sporadically. The clinical causes for these differences remain unclear.