[Dobutamine doppler echocardiography in severe aortic stenosis with left ventricular dysfunction. Comparison with postoperative examination]. / Apport de l'échocardiographie Doppler sous dobutamine dans le rétrécissement aortique serré avec dysfonction ventriculaire gauche. Comparaison aux données postopératoires.

The association of left ventricular dysfunction with aortic stenosis worsens the spontaneous prognosis and increases operative mortality. The aim of this prospective study was to assess the predictive value of dobutamine Doppler echocardiography on the indices of left ventricular contractile function in patients with aortic stenosis and left ventricular dysfunction (LVEF < 0.45) undergoing aortic valve replacement. Eighteen patients, including 9 with coronary artery disease, were included in a protocol consisting of analysis of left ventricular function and of the severity of aortic stenosis before, during dobutamine infusion, and after valvular replacement. The dobutamine was given in progressive increments of 5 micrograms/Kg up to a maximum of 20 micrograms/Kg. During pharmacological stress, the functional aortic valve area increased from 0.46 +/- 0.15 to 0.56 +/- 0.23 cm2. Tolerance of the procedure was good. All but 2 patients improved their postoperative ejection fraction with values equivalent to those observed during the last increment of dobutamine (r = 0.73; p < 0.003). The patients with initial mean pressure gradients > 50 mmHg normalised their LVEF after valve replacement. The authors conclude that dobutamine echocardiography is useful for predicting the values of postoperative left ventricular contractile indices when severe aortic stenosis is associated with systolic dysfunction. It allows evaluation of the expected short term benefits to these indices after aortic valve replacement.

[Acoustic quantification of right ventricular dimensions and systolic function]. / Estimation par quantification acoustique des dimensions et de la fonction systolique du ventricule droit.

In view of the important prognostic significance of right ventricular systolic function, there have been many non-invasive studies of this subject. The majority of these studies have been limited by difficulties in modelisation of this geometrically complex cardiac chamber. Automatic border detection by acoustic quantification based on the back scatter of ultrasound provides a "direct" method of analysing right ventricular dimensions and functions. The authors undertook a prospective study of 34 patients to evaluate the reliability of this technique in measuring the surfaces and fractional shortening of the right ventricle. The feasibility was 92%. The correlation coefficients between the manual two-dimensional technique and automatic border detection were 0.81 for the end diastolic surface areas, 0.85 for the end systolic surface areas and 0.74 for the fractional shortening. Compared with the isotopic ejection fraction, the correlation coefficient was 0.73. The authors conclude that acoustic quantification is a feasible and reliable technique of measuring right ventricular dimensions and its contractile function.

[Transthoracic echocardiography and diagnosis of acute pulmonary embolism. Change in the diagnostic valve with respect to thresholds of classification]. / Echocardiographie transthoracique et diagnostic d'embolie pulmonaire aiguë. Variation de la valeur diagnostique en fonction des seuils de classification.

The diagnostic value of transthoracic echocardiography in acute pulmonary embolism is not well established. Although many parameters are abnormal, the thresholds used vary according to the authors, limiting the contribution of the investigation to the diagnosis. In a prospective study of 70 patients with suspected acute pulmonary embolism without previous cardio-respiratory disease, the authors tried to determine the diagnostic thresholds using discriminating linear analysis and ROC curves. Parameters easily recorded in an emergency were analysed: end diastolic ventricular dimensions, ratio of these diameters and maximal velocity of tricuspid regurgitant flow. Thirty-one patients had pulmonary embolism quantified by the Miller index (average: 16 +/- 7, range 2 to 28). Measurements of left ventricular dimension were disappointing (sensitivity: 0.52, specificity: 0.73 for a threshold value of 45 mm). The right ventricular dimension was a better predictive parameter (sensitivity: 0.70, specificity: 0.86 for a threshold value of 25 mm). However, the ratio of right to left ventricular dimension had a better diagnostic value (sensitivity: 0.85, specificity: 0.78 for a threshold value of 0.5). The best diagnostic parameter was the maximal velocity of tricuspid regurgitation (sensitivity: 0.93, specificity: 0.82 for a threshold value of 2.5 m/s). The authors conclude that the maximal velocity of tricuspid regurgitation with a threshold of 2.5 m/s and the ratio of the ventricular dimensions with a threshold value of 0.5 are valuable diagnostic indicators for acute pulmonary embolism.

[Estimation of left ventricular volumes and ejection fraction with acoustic quantification in myocardial infarction. Comparison with echocardiographic, angiographic and scintigraphic data]. / Estimation des volumes et de la fraction d'éjection ventriculaires gauches par quantification acoustique dans l'infarctus du myocarde. Comparaison aux données échographiques, angiographiques et scintigraphiques.

The object of this study was to assess the reliability of measurements of left ventricular volumes and ejection fraction by acoustic quantification by the method of summation of discs in acute myocardial infarction. Thirty-two patients with an average age of 55.9 +/- 12 years were studied prospectively on average 6 +/- 2 days after the onset of myocardial infarction. Within 48 hours, the patients underwent TM echocardiography (Teichholz's method) two-dimensional echocardiography (Simpson's method on freeze frames and acoustic quantification) before left ventricular angiography and isotopic ventriculography, considered as the reference methods for comparing left ventricular volumes and ejection fractions. The data displayed in real time by acoustic quantification correlated well with the results of left ventricular angiography (r = 0.77; p = 0.0001) and moderately underestimated (+4.1 +/- 11.9%) the ejection fraction, but were relatively disappointing for estimating volumes. When compared with isotopic ejection fraction, the correlation coefficient was r = 0.71 (p = 0.0004) and the values were overestimated. In this study, acoustic quantification was the most reliable echocardiographic method of assessing the left ventricular ejection fraction with reference to contrast angiography (Teichholz: r = 0.56; p = 0.0014; Simpson: r = 0.76; p = 0.001). The authors conclude that assessing the left ventricular ejection fraction with acoustic quantification is reliable in acute myocardial infarction. However, the method is not very accurate in measuring end systolic and end diastolic volumes.

[Value of transesophageal echocardiography in post-infarction septal ruptures]. / Intérêt de l'échographie transoesophagienne dans les ruptures septales postinfarctus.

The role of transoesophageal echocardiography in the diagnosis of ventricular septal defect in the acute stage of myocardial infarction, was evaluated in 15 consecutive patients (10 men and 5 women) with a mean age of 72 years in the period between June 1991 and April 1995. The patients had 11 anterior infarcts and 4 inferior infarcts with extension to the right ventricle. One patient was in Killips class I,7 patients in class II, 2 in class III and 5 in class IV. Only 8 of the 15 septal ruptures could be visualised directly by conventional transthoracic echocardiography, though all 15 were suspected from continuous Doppler and colour Doppler analysis. Transoesophageal echocardiography was successfully performed in 14 of the 15 patients with a monoplane probe in 11 cases and a multiplane probe in 3 cases. The average duration of the procedure was 12 minutes and clinical and haemodynamic tolerance was good. Ventricular septal defect was directly visualised in all cases in the short axis transgastric view and in 7 cases in transoesophageal views. Transoesophageal echocardiography was concordant with peroperative findings with regards to the site of ventricular septal defect (8 apical, 5 postero-basal and 1 median), their type (6 punched-out defects, 5 fissures, and 3 perforated aneurysms), their size (average 9.3 mm), their number with 5 multiple defects, and associated lesions (4 right ventricular extensions, 4 hemopericardiums and 1 free wall fissure). Transoesophageal echocardiography completes traditional transthoracic echocardiographic examination in the diagnosis of post-infarction ventricular septal defect. It is well tolerated and, in the authors' experience, allows limitation of invasive procedures to coronary angiography alone.

Regression of right ventricular hypokinesis after thrombolysis in acute pulmonary embolism.

We found a significant ABD-assisted right ventricular hypokinetic regression after thrombolytic therapy in acute pulmonary embolism but could not demonstrate a linear relation between improvement in early right ventricular function and angiography.

Use of transthoracic Doppler echocardiography combined with clinical and electrocardiographic data to predict acute pulmonary embolism.

Transthoracic echocardiography and continuous wave Doppler were prospectively performed in 132 out-patients with suspicion of pulmonary embolism, and who had no previous history of severe cardiac or pulmonary disease. Bedside echocardiography determined diagnosis other than pulmonary embolism in 55 patients. Further study was completed in 70 patients; pulmonary embolism was found in 31 and excluded in 39. Significant differences were found as regards right ventricular diameter (27 +/- 8 vs 22 +/- 5 mm, P < 0.001), left ventricular diameter (41 +/- 9 vs 49 +/- 7 mm, P < 0.001), right over left ventricular diameter ratio (0.67 +/- 0.23 vs 0.43 +/- 0.15, P < 0.0001), tricuspid regurgitant flow peak velocity (2.9 +/- 0.4 vs 2.4 +/- 0.7 m.s-1, P < 0.0001), and abnormal septum motion (12 vs 4, P < 0.01). Multivariate analysis of echocardiographic data included a tricuspid regurgitant flow peak velocity greater than 2.5 m.s-1 and a right over left ventricular diameter ratio greater than 0.5 in a logistic model (sensitivity 93%, specificity 81%). The combination of echocardiographic and non-echocardiographic data included the two previous echocardiographic variables, together with signs of deep vein thrombosis, a deep S wave in lead D1, and a Q wave in lead D3 on the electrocardiogram in a logistic model (sensitivity 96%, specificity 83%). It can be concluded that emergency echocardiography, alone or combined with clinical examination and electrocardiogram, satisfactorily predicts acute pulmonary embolism.

Floating right heart thrombi and pulmonary embolism: diagnosis, outcome and therapeutic management.

The aim of this study was to analyze clinical and echographic findings and to assess therapeutic management in 14 floating right atrial thrombi diagnosed with systematic echocardiography in 200 consecutive patients with proven pulmonary embolism. Auscultatory findings were abnormal in 7 cases, 4 of them showing signs of tricuspid obstruction. Echocardiography displayed a mobile ovoid, polycyclic or worm-like right atrial mass, always associated with signs of cor pulmonale. Four patients (29%) died, 2 of them before any treatment could be started. Regarding the remaining 10 patients with favorable outcome, surgical embolectomy was carried out in 7. Our data suggest that echocardiographic examination is necessary in all suspected pulmonary embolisms and has to be done quickly for emergency treatment in patients with floating right atrial thrombus.