Transesophageal echocardiography demonstrated hyperdynamic small left ventricular cavity that was consistent with significant intravascular volume depletion (n = 3), severe left ventricular dysfunction (n – 3), right ventricular infarction (n = 2), ventricular septal rupture following myocardial infarction (n = 1), traumatic ventricular septal defect falling from height (n = 1), dehisced poly-tetrafluorethylene (Gore-Tex) graft after total cavopulmonary connection of complex congenital heart disease (n – 1), and patent ductus arteriosus (n = 1) in the remaining patients. In the patient with patent ductus arteriosus, the size of the duct was large (2 cm in diameter) resulting in high cardiac output heart failure that subsided after ligation of the patent ductus. Transesophageal echocardiography detected an atrial septal aneurysm bulging toward the left atrium and right to-left shunt through a patent foramen ovale in one patient with right ventricular infarction and persistent hypoxemia despite 100 percent oxygen therapy. Transthoracic echocardiography was unable to detect the mechanical valve thrombus in three patients, dehisced Gore-Tex graft, patent ductus arteriosus, postinfarction ventricular septal rupture, and atrial septal aneurysm with patent foramen ovale each in a single patient, and ruptured chordae tendineae in two patients (Table 2). In the group with hemodynamic instability, nine patients underwent cardiac surgery that confirmed the TEE findings in all. Of these, three patients with mechanical valve thrombus, two with acute mitral regurgitation due to ruptured chordae tendineae, one with dehisced Gore-Tex graft, and one with postinfarction ventricular septal rupture directly underwent surgery after the TEE diagnosis. canadian pharmacy
In the group with suspected cardiac source of cerebral embolism, all patients had underlying heart diseases, including rheumatic heart disease in seven patients, prosthetic valve replacement in two, and hypertrophic cardiomyopathy with atrial fibrillation in two. These 11 patients all had major stroke with profound neurologic deficit that threatened the respiratory and cardiovascular stability Transesophageal echocardiography detected left atrial thrombus in one patient, left atrial appendage thrombus in five, and only left atrial spontaneous echo contrast without thrombi in three. Neither spontaneous echo contrast nor any of the thrombus was detected by TTE. After TTE and TEE studies, no cardiac source of embolism was found in two patients.
Seven patients underwent TEE to evaluate the severity of mitral regurgitation. The severity of mitral regurgitation diagnosed by TEE was confirmed by left ventriculography using Sellers’ criteria. Only mild mitral regurgitation was diagnosed by TTE in three patients with prosthetic valve dysfunction while severe mitral regurgitation was found by TEE in all. The severity of mitral regurgitation diagnosed by TTE and TEE in the other four patients was the same.
Suspected infective endocarditis was the reason for the TEE study in six patients. This diagnosis was ruled out in three. A small vegetation in the aortic valve in one patient and aortic valve ring abscess (Fig 3) in two patients complicating infective endocarditis were missed by TTE but detected by TEE. The two patients with aortic valve ring abscess directly underwent open heart surgery with uneventful outcome.
Table 3 summarizes the usefulness of TTE and TEE in the detection of specific cardiac abnormalities in the critical ill patients. Transesophageal echocardiography was superior to TTE in diagnosing aortic dissection, in the treatment of patients with hemodynamic instability, and in detecting cardiac source of embolism.
No significant complications such as esophageal perforation, aspiration pneumonia, and arrhythmia during TEE were recorded. The procedures were generally well tolerated. Only transient mild elevation of BP and tachycardia occurred. These transient hemodynamic changes returned to preprocedure state after removal of the transesophageal probe.
Table 2—Comparison of Transthoracic and Transesophageal Echocardiography in the Diagnosis of 20 Patients With Hemodynamic Instability
|Mechanical valve thrombus (n = 3) Severe mitral regurgitation (n = 5)||0||3|
|Ruptured chordae tendineae (n = 4)||2||4|
|Periprosthetic (n = 1)||1||1|
|Dehisced (Gore-Tex) graft (n = 1)||0||1|
|Patent ductus arteriosus (n = 1)||0||1|
|Postinfarction septal rupture (n – 1)||0||1|
|Right ventricular infarction (n = 2)|
|Atrial septal aneurysm with PFO (n = 1)||0||1|
|Right ventricular infarction only (n = 1)||1||1|
|Left ventricular dysfunction (n = 3)||3||3|
|Traumatic septal rupture (n = 1)||1||1|
|Hyperdynamic small left ventricle (n – 3)||3||3|
Table 3—Comparison of Transthoracic and Transesophageal Echocardiography in the Detection of Specific Cardiac Abnormalities in the Critically III Patients
|Aortic Dissection (n = 27)||Hemodynamic Instability (n = 20)||Cardiac Source of Embolism (n =11)||Evaluation of MR Severity’ (n = 7)||InfectiveEndocarditis(n = 3)|
Figure 3. Transesophageal short axis view at the level of aortic valve showing echolucent area (asterisks) near the noncoronary cusp (arrow), indicating the presence of valve ring abscess. AV = aortic valve; LA = left atrium; RT = right ventricular outflow tract.