Large atrial appendage thrombus in the presence of severe mitral regurgitation: contradictory hemodynamics or expected findings

A case of a large left atrial appendage thrombus in the presence of severe mitral regurgitation is presented. The use of transesophageal echocardiography in this setting was not only useful but also crucial despite the low anticipated diagnostic yield given the expected altered left atrial flow dynamics from the turbulent regurgitant lesion. However, additional confounding factors could have acted as potential mechanisms to enhance thrombosis in this setting and consequently are discussed.     

Esophageal Doppler: noninvasive cardiac output monitor

In this article we describe the esophageal Doppler, a noninvasive, instantaneous cardiac output monitor. Its reliability has been demonstrated to be comparable to that of other current techniques used in the clinical arena to measure cardiac output. It helps guiding intravascular fluid resuscitation by quantifying the increase in flow in response to fluid challenges and by indicating the plateau of the patient's cardiac function curve. When the plateau has been reached, further fluid loading may result in congestion without improvement in systemic flow. Thus, measuring cardiac output is the only way to determine the upper limit for fluid intake. In addition, a strategy based on cardiac output optimization has proven beneficial in high-risk surgical patients.     

Transesophageal echocardiographic identification of right vertebral artery

We describe a transesophageal technique for identifying the origin and precervical course of the right vertebral artery with the probe positioned in the upper esophagus. The technique was successful in 9 of 11 patients in whom it was attempted.     

Fibrotic aortic stenosis in a patient with dwarfism

In this report, we present an adult patient with dwarfism who had severe aortic stenosis with markedly thickened fibrotic valve leaflets without calcification. These findings were well demonstrated by both two- and three-dimensional transesophageal echocardiography and confirmed at surgery and by pathological examination.     

Risk of thromboembolism in acute atrial fibrillation or atrial flutter

Atrial fibrillation (AF) is the most common sustained cardiac dysrhythmia, predominating in the elderly, with stroke as a potentially devastating complication. Prevention of the thromboembolic sequelae from AF remains a central focus of practicing clinicians. Although the risk of thromboembolism in chronic AF is well recognized, less is known about the potential risk of systemic embolism in acute AF. In addition, recent data support the notion of a group at considerable risk of embolism from atrial flutter, an arrhythmia typically believed to bestow little increased risk of thromboembolism. The mechanism of thrombus formation, embolization, and resolution in atrial arrhythmias is not well defined, particularly in that of acute AF or atrial flutter. The traditional concept proposes that atrial thrombus forms only after > 2 days of AF and embolizes by being dislodged from increases in shear forces. This widely accepted concept further holds that newly formed atrial thrombus, in the setting of AF, organizes over a span of 14 days. The results of studies based on observations from transesophageal echocardiography examinations have provided provocative insight into the temporal sequence of atrial thrombus formation, embolization, and resolution in AF or atrial flutter and have expanded the traditional concept of thromboembolism in these atrial dysrhythmias. Namely, left atrial thrombus may form before the onset of AF in the face of sinus rhythm. Conversion to sinus rhythm may increase the thrombogenic milieu of the left atrium. Importantly, atrial thrombus may form in the acute phase of AF. Last, thrombi may require > 14 days to become immobile or to resolve. Findings similar to those of acute AF have been reported in patients with atrial flutter and coexisting cardiac pathology. On the basis of these emerging insights fostered by the use of transesophageal echocardiography, it appears appropriate to consider anticoagulation in patients presenting with acute AF or atrial flutter with coexisting cardiac pathology predisposing to left atrial thrombus.     

The safe use of intraoperative transesophageal echocardiography in the management of total anomalous pulmonary venous connection in newborns and infants: a case series

BACKGROUND: Intraoperative transesophageal echocardiography (TEE) is useful in evaluating the repair of lesions in patients with congenital heart disease. But the use of TEE in infants with total anomalous pulmonary venous connection (TAPVC) remains unclear. We reviewed the safety and efficacy of intraoperative TEE during TAPVC repair. METHODS: Twenty-eight consecutive 1 day to 7 month-old infants with TAPVC (14 supracardiac, six intracardiac and eight infracardiac type) had surgical repair with intraoperative TEE monitoring. RESULTS: Four patients received immediate surgical revision after primary surgery for residual anastomotic stenosis diagnosed by TEE. In addition, two unsuspected ventricular septal defects and three persistent ductus arteriosus were detected before surgery. Eight infants (29%) had hypotension and hypoxemia associated with TEE probe insertion before surgery, but this hemodynamic disturbance returned to baseline value after withdrawing the TEE probe from the esophagus. However, these eight patients had uneventful TEE probe insertion following sternotomy. The mechanism was probably because of the reduction of intrathoracic pressure when the chest was opened. CONCLUSIONS: TEE probe insertion in TAPVC patients may pose a potential risk of compression of pulmonary venous confluence resulting in hemodynamic instability. Therefore, we suggest that the use of TEE in such TAPVC patients appears to be safer after sternotomy.     

Diagnosis of patent foramen ovale with multiplane transesophageal echocardiography in adult cardiac surgical patients

OBJECTIVE: To evaluate multiplane transesophageal echocardiography (TEE) for detection of patent foramen ovale (PFO) and to compare multiplane TEE with visual inspection (VI) for PFO detection. DESIGN: A prospective observational study. SETTING: University hospital (single institution). PARTICIPANTS: Patients presenting for cardiac surgery requiring TEE. INTERVENTIONS: Multiplane TEE including 2 atrial views with color-flow Doppler (CFD) and contrast echocardiography (CE) with a provocative respiratory maneuver (PRM) and comparison of multiplane TEE and VI with respect to PFO detection. MEASUREMENTS AND MAIN RESULTS: The cohort size was 187. PFO prevalence was 27.3%. CFD with serial decrease of the Nyquist limit detected 51% of all PFO: 41.2% in the bicaval view alone, 27.5% in the 4-chamber view alone, and 9.8% in both views. CE detected 78.4% of all PFO: 72.5% with PRM, 45.1% with no PRM, and 27.4% with/without PRM. PFO detection by multiplane TEE and visual inspection were correlated in 41 subjects. TEE diagnosed 11 PFO (26.8% prevalence, 3 missed by VI). VI diagnosed 12 PFO (29.3% prevalence, 4 missed by TEE). CONCLUSIONS: Multiplane TEE is a gold standard for detection of PFO. Despite advances in TEE technology, 2-dimensional imaging does not detect all PFO. To maximize PFO detection, multiple TEE modalities are required in multiple views, despite a low Nyquist limit for CFD or a PRM for CE. Even though multiplane TEE is equivalent to VI for PFO detection, the discrepancy rate may be an important consideration in the individual case.