Other cardiac diseases

Abstract

Diagnosis of a left atrial (LA) myxoma is relatively easy by echocardiography, and especially by two-dimensional echocardiography. This method is useful for diagnosis of not only the presence of a myxoma, but also for the evaluation of its characteristics, including size, the site of attachment, consistency (fragile or not) and motility. Echocardiography is the method of choice for its clinical diagnosis and also has replaced angiocardiography for routine preoperative evaluation. The most usual appearance of a left atrial myxoma is that of a pedunculated large mass with well defined structure. The mass usually prolapses into the mitral orifice during diastole, and this can produce left ventricular inflow obstruction (Figures 7.1, 5). In systole, the tumor thrusts back into the left atrial cavity. Sometimes, myxoma has no stalk and does not prolapse to the mitral orifice (Figures 7.8, 9) or is so small that the mitral valve motion and the transmitral flow is not disturbed (Figures 7.10, 11). The hemodynamic alterations of left ventricular filling when a myxoma is present depend on its size and whether it prolapses into the left ventricle or not. Doppler echocardiography can provide information about hemodynamic alteration due to left atrial myxoma, consisting of disturbance of left ventricular filling (Figures 7.3,4, 7) and sometimes mitral regurgitation (Figure 7.12). In the M-mode, one can see a cloud of tumor echoes in the left atrium and frequently tumor echoes are recorded behind the anterior leaflet of the mitral valve (Figures 7.2, 6, 9, 11). The E–F slope may be decreased, reflecting disturbance of left ventricular filling.