Medicine of the Future in America

Usefulness of Transesophageal Echocardiography in the Treatment of Critically III Patients: Results

A total of 80 TEE studies were attempted in 80 patients. Transesophageal probe was passed successfully in 78 of 80 attempts (98 percent). The causes of failure to pass the probe into the esophagus include poor cooperation in one awake patient and esophageal narrowing in one ventilated patient.
Indications
The indications for TEE imaging included suspected aortic dissection in 34 patients, hemodynamic instability in 22, suspected cardiac source of embolism in 11, evaluation of mitral regurgitation severity in 7, and suspected infective endocarditis in 6. The indications for TEE study in 48 ICU patients and in 32 emergency department patients are listed in Table 1. Systolic blood pressure <90 mm Hg and heart rate >100 beats per minute occurred in 20 patients (25 percent). These included aortic wall rupture in two, aortic dissection in five, hypovolemic shock in three, cardiogenic shock in six, major stroke in two, and infective endocarditis in two. Ten of the 17 patients who were mechanically ventilated were in the shock state. canadianneighborpharmacy.com

Transthoracic vs Transesophageal Echocardiographic Findings
In the group with suspected aortic dissection, aortic dissection was proved in 27 patients, aortic wall rupture and ascending aortic aneurysm each in 2, and normal aorta in the remaining 3 by computed tomography, magnetic resonance imaging, aortography, or surgery. Surgery was performed and confirmed the diagnosis in 14 patients with aortic dissection and 2 patients with aortic wall rupture. Of the 27 patients with aortic dissection, only 12 patients had their conditions diagnosed by TTE (sensitivity, 44 percent), while all had their conditions diagnosed by TEE (sensitivity, 100 percent). Two patients with aortic wall rupture were falsely diagnosed as having DeBakey type 2 dissection by TEE. Transesophageal echocardiography classified the types of dissection correctly: type 1 in 8 patients, type 2 in 4, and type 3 in 15 according to the classification of DeBakey et al. Five patients with aortic dissection and hypotension underwent operation after diagnosis by TEE without other examinations. In addition to the significantly higher sensitivity of TEE than that of TTE (100 percent vs 44 percent, p<0.005) in the diagnosis of aortic dissection, TEE provided more information about the site and number of intimal tears (Fig 1), flow through the intimal tear, and presence of thrombus or spontaneous echo contrast in the false lumen than did TTE.
In the group with hemodynamic instability, a transesophageal probe was passed successfully in 20 of the 22 patients. Of these 20 patients, 13 patients had acute lung edema or severe congestive heart failure (New York Heart Association functional class 4), 4 had postmyocardial infarction complication, 1 had persistent cyanosis after total cavopulmonary connection of complex congenital heart disease, and 2 had indeterminate cause of shock. Transesophageal echocardiography detected mechanical prosthetic valve dysfunction with thrombus formation (Fig 2) in three patients. Transesophageal echocardiography showed severe mitral regurgitation in five patients that was due to ruptured chordae tendineae in four and periprosthetic mitral regurgitation in one.

Table 1—Indications for Transesophageal Echocardiography in Patients in the ICU and in the Emergency Department

SuspectAD(n = 34) HemodynamicInstability(n = 22) * Cardiac Source of Embolism(n = H) Evaluation of MR Severity(n = 7) ‘ SuspectedIE(n = 6)
ICU (n = 48) 29 13 3 2 1
ED(n = 32) 5 9 8 5 5

Figure-1

Figure 1. Transesophageal echocardiogram in a patient with suspected aortic dissection showing descending thoracic aorta separated by an intimal flap (arrowhead) into true lumen (TL) and false lumen (FL). The intimal tear (arrow) is clearly shown.

Figure-2

Figure 2. Transesophageal four-chamber view demonstrating a well-defined thrombus (arrow) attached to the mechanical valve (M) at the mitral position. l^A – left atrium; RA – right atrium.

This entry was posted in Critically III Patients and tagged aortic dissection, cardiac source, critically ill patients, infective endocarditis, transesophageal echocardiography.
Copyright © 2012 Medicine of the Future in America www.perfexis.org