Summary:To assess the mechanism of mitral regurgitation in ventricular dilatation, 24 patients with dilated cardiomyopathy ( 1 3 with and 1 I without mitral regurgitation) and 10 normal individuals were studied by two-dimensional echocardiography. Left ventricular dimensions and mitral ring diameters in systole and diastole were measured in the long-axis section, and systolic interpapillary muscle distance in the short-axis section. The results showed: ( I ) Mitral ring diameter is increased in most patients with dilated cardiomyopathy. (2) Neither increased ring diameter. reduced ring contraction, nor decreased interpapillary muscle distance determine the presence of mitral regurgitation. (3) The only difference between those patients with and without mitral regurgitation was the degree of left ventricular dilatation (p

Prolapse of the mitral valve in patients with secundum atrial septal defect has been described angiographically and by two-dimensional echocardiography. It has been suggested that prolapse of the mitral valve in these patients is due to distortion of left ventricular shape and small left ventricular volume. To test this hypothesis 10 patients with unrepaired secundum atrial septal defect and 10 patients who had undergone repair of the defect were studied by two-dimensional echocardiography. The prevalence of mitral valve prolapse was 80% in the unrepaired group and 20% in the repaired group (P less than 0.01). Short axis of the left ventricle revealed septal bulging into the left ventricle, the end-diastolic ratio of minor to major axis being 0.71 in the unrepaired group and 0.93 in the repaired group (P less than 0.001). Systolic and diastolic cross-sectional areas were larger in the repaired group compared with the unrepaired group (P less than 0.05). Prolapse of the mitral valve in patients with secundum atrial septal defect may be related to the distorted left ventricular shape and small left ventricular volume.

Left atrial thrombi were shown by two-dimensional echocardiography in three patients with mitral valve disease and neurological symptoms. In two patients the atrial thrombi had probably been the source of a previous cerebrovascular embolus. In the third, twodimensional echocardiography detected the development of a recent ball-valve thrombus in the left atrial cavity, which caused intermittent obstruction and syncope. Echocardiographic findings were correlated with anatomical and histological data in all three patients. The spatial orientation provided by the multiple imaging planes of two-dimensional echocardiography permitted correct estimates of the size and position of the thrombus, and this mode was superior to the standard M-mode technique for non-invasive imaging of thrombus. Despite limitations of technique and resolution, the information provided by ultrasound can be extremely helpful in the management of patients. Ultrasonic screening (particularly the two-dimensional mode) is to be recommended in patients with neurological symptoms and clinical evidence of cardiac disease or arrhythmia.The range of cardiac conditions that may predispose to embolism is extensive; early recognition of these may in some cases lead to appropriate treatment and so avert disastrous neurological complications. The purpose of this paper is to show the value of ultrasound and in particular of two-dimensional echocardiography in the diagnosis of atrial thrombi. MethodsEchocardiography We performed conventional M-mode echocardiography using standard equipment with strip-chart recording of the ultrasonic data. The cross-sectional two-dimensional echocardiography studies were performed with a mechanical sector scanner (Smith-Kline Instruments Ekosector I) having a scanner probe containing a transducer mechanically driven through 300 sector at 30 cycles (60 frames) a second. Gain settings and reject control were optimised to avoid misinterpretation of structures. Cross-sectional images were recorded on videotape; the images were then available for analysis in real-time, slow-motion, or single-frame format. In the static pictures there was, however, loss of visual integration that normally occurs during dynamic recordings. The standard two-dimensional echocardiography was performed on several crosssectional imaging planes through the heart, from all available acoustic windows, including the parasternal, subcostal, and apical transducer positions.Address for reprint requests: Dr RM Donaldson, National Heart Hospital, Westmoreland Street, London WlM 8BA.Histological methods Tissue from the three patients reported in detail in this paper was available for histopathological study. Areas were selected from suitable sites, processed, and paraffin embedded, 5-,um thick sections were then cut and stained with haematoxylin and eosin, Milleres elastic van Gieson, and, where appropriate, Martius scarlet blue stains. Case studiesCase I A 36-year-old man with intermittent atrial arrhythmias and progressive dyspnoea from nonrheumatic mit...

(1) chordal or leaflet participation in SAM is relevant to the presence and degree of obstruction; (2) leaflet involvement usually implies severe obstruction; (3) distortion of the mitral valve apparatus may contribute to the genesis of mitral regurgitation.

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