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Acute aortic insufficiency can now be diagnosed rapidly and accurately thanks to Doppler echocardiography. The etiologies include infectious endocarditis, aortic dissection, bioprosthesis degeneration and thoracic injury. The clinical diagnosis is substantiated by the particular etiological context, dyspnea and pulmonary edema being the main factors involved. Examination includes finding out whether there is a reduction in the first sound, S1 a generally brief apical diastolic murmur. Echocardiography detects the presence of aortic leakage, the acute character of which is confirmed by the findings of a premature closure of the mitral valve, the existence of telediastolic mitral leakage, a restriction in the transmitral flow, and finally, the absence of left ventricular dilatation. An emergency operation is recommended by most authors in the case of acute aortic leakage due to the major risk or mortality resulting from pulmonary edema, ventricular arrhythmias, electromechanical dissociation or cardiogenic shock.

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.

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, P0.001), left ventricular diameter (41 +/- 9 vs 49 +/- 7 mm, P0.001), right over left ventricular diameter ratio (0.67 +/- 0.23 vs 0.43 +/- 0.15, P0.0001), tricuspid regurgitant flow peak velocity (2.9 +/- 0.4 vs 2.4 +/- 0.7 m.s-1, P0.0001), and abnormal septum motion (12 vs 4, P0.01). 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.

Thrombolytic agents are widely used as first line treatment in severe acute pulmonary embolisms. While their indications are well defined, no controlled trial exists to provide definite evidence of their ultimate effectiveness in terms of mortality. Nevertheless, therapeutic advances and the good results obtained in terms of satisfactory changes in hemodynamic and angiographic parameters have led to renewed evaluation at the present time of the ways in which they are used in thrombo-embolic disease: administration of thrombolytics as repeated boluses in order to decrease the risk of hemorrhagic complications; and extension of the indications of thrombolysis to the venous component of thrombo-embolic disease.

The authors report two cases of posterior ventricular septal defects complicating acute myocardial infarction diagnosed by transesophageal echocardiography. Transesophageal echocardiography was well tolerated confirmed the diagnosis, and enabled accurate evaluation of the shunt in the transgastric view. The anatomical results guided the surgical approach and correlated well with the operative findings.

A prospective study of 18 patients admitted to hospital for acute pulmonary embolism confirmed the reliability of continuous wave cardiac doppler as a non-invasive method of evaluating systolic pulmonary artery pressures. These pressures were calculated by applying the simplified Bernoulli equation to the maximal velocity of regurgitant tricuspid flow and compared with the results of cardiac catheterisation and angiography, the percentage of vascular obstruction being assessed using Miller's index. The correlations between the two methods were good, r = 0.96; p less than 0.001, with a standard error of +/- 5.2 mmHg. The correlations between the velocity of tricuspid flow and the percentage of obstruction were less significant (r = 0.65; p less than 0.005) but improved when patients with pre-existing cardiopulmonary disease were excluded. This technique of non-invasive assessment of haemodynamic parameters also helps in evaluating the underlying pathology; tricuspid regurgitation with velocities greater than 3.5 m/s is associated with pre-existing chronic cor pulmonale, information of prognostic interest which would guide therapeutic management.