Transesophageal two-dimensional echocardiography in the critically ill--is the Swan-Ganz catheter redundant?

Swan-Ganz catheterization can facilitate intra-operative management of critically ill patients. The derived data lacks specificity, however, and, as such, is frequently misleading. This disadvantage, combined with recent advances in echocardiography imaging techniques, has resulted in increasing application of transesophageal (TE) two-dimensional echocardiography (2D-echo) to supplement and, in instances, to supplant conventional cardiac monitoring. This paper reviews the current status of single-plane TE 2D-echo as it pertains to evaluation of left ventricular (LV) volume status, performance, and ischemia. It is concluded that, while 2D-echo multiple-plane analyses provide an accurate representation of LV dimensions, interpretation of TE single-plane end-diastolic measurements should be limited to differentiation between extremes of LV volume. In contrast, corresponding estimates of LV ejection fraction correlate closely with overall performance, at least in cases without asynergy. Finally, the capacity of TE 2D-echo to detect LV regional wall-motion abnormalities can be particularly useful. Such abnormalities commonly represent early manifestations of ischemia and can, in addition, be predictive of subsequent outcome.