Impact of intraoperative transesophageal echocardiography among patients undergoing aortic valve replacement for aortic stenosis.

In this study, we sought to define the impact of intraoperative transesophageal echocardiography (IOTEE) among patients undergoing aortic valve replacement for severe aortic stenosis. We reviewed the clinical data and preoperative, intraoperative, and postoperative echocardiograms of all adults who underwent aortic valve replacement for aortic stenosis and had IOTEE between January 1993 and December 1996. There were 383 patients (223 men, 160 women; mean age, 69 years). Fifty-four (14%) of the 383 patients had mitral valve surgery at the time of aortic valve replacement. In 6 patients, mitral valve surgery was not planned but was added because of findings on IOTEE. In 25 patients, mitral valve surgery was canceled on the basis of the IOTEE. Additional information was found by IOTEE in 25 patients before and after bypass, altering the surgical plan in 18 of these 25 patients. Overall, IOTEE altered the planned operation in 49 (13%) of the 383 patients. These data support the routine use of IOTEE among patients undergoing aortic valve replacement for aortic stenosis.

More than just the "Q-tip sign".

In the early days of transesophageal echocardiography, the "Q-tip sign" was occasionally mistaken for a left atrial mass. This area is now well recognized as a normal anatomic landmark dividing the left atrial appendage from the left upper pulmonary vein. However, in this report we describe 2 patients in whom pathology was found in this area, which should not be overlooked.

The role of intraoperative transesophageal echocardiography in patients undergoing cardiac mass removal.

To evaluate the role of intraoperative transesophageal echocardiography (IOTEE) during surgical removal of cardiac masses, we studied 75 consecutive patients (34 men, aged 56 +/- 16 years, range 17 to 82 years) who underwent surgery primarily for cardiac mass removal with the adjunct of IOTEE for the years 1993 through 1998. The IOTEE provided new information before bypass in 6 patients (8%), altering the planned surgical procedure in all. A newly discovered patent foramen ovale was closed in 2 patients, a second myxoma discovered in one patient, a mitral valve repaired in one patient, inferior vena caval cannulation site clarified in one patient, and in one patient the mass was no longer present and the surgery canceled. In 10 patients (13%), new post-bypass information was found, which prompted return to bypass for valve repair in 3 patients, altered nonsurgical management in 3 patients, and did not necessitate specific measures in 4 patients. Thus, in 75 patients coming to surgery for mass removal, IOTEE affected intraoperative management in 12 (16%).

Entrapment of subvalvular mitral tissue causing intermittent failure of a St Jude mitral prosthesis.

Frequently portions of the mitral valve and sub-valvular apparatus are left intact during mitral valve replacement to help preserve left ventricular function. We describe a patient with paroxysmal congestive heart failure caused by intermittent entrapment of the subvalvular apparatus in the prosthesis, preventing complete valve closure.

Intraoperative transesophageal echocardiography: 5-year prospective review of impact on surgical management.

OBJECTIVE: To determine the impact of intraoperative transesophageal echocardiography (IOTEE), an important adjunct in many types of cardiac surgical cases, on the surgical decisions made perioperatively in adult patients undergoing cardiac surgery. PATIENTS AND METHODS: All adult patients who had cardiac surgery between 1993 and 1997 and who also had IOTEE were studied. New findings before and after cardiopulmonary bypass and alterations in the planned surgical procedure or management were documented prospectively. RESULTS: A total of 3245 patients (60% men, 40% women; aged 18-93 years with a mean +/- SD age of 62 +/- 15 years) were included in the study. The most common operations performed were mitral valve repair (26%) and aortic valve replacement (22%). Over the 5-year period, 41% of patients had IOTEE. New information was found before bypass in 15% of patients, directly affecting surgery in 14% of the patients. The most common new prebypass information found was patent foramen ovale resulting in closure in the majority of patients. New information was found after bypass in 6% of the patients, resulting in a change in surgery or hemodynamic management in 4% of the total. The most common postbypass finding was valvular dysfunction with repeat bypass in most patients for re-repair or replacement. No major complications occurred. CONCLUSION: In adult patients undergoing cardiac surgery, IOTEE provides important important information both before and after bypass that affects surgical and hemodynamic management.

Intraoperative application of power Doppler imaging: visualization of myocardial perfusion after anastomosis of left internal thoracic artery to left anterior descending coronary artery.

The purpose of this study was to determine the role of power Doppler imaging in assessing patency of coronary artery bypass graft (CABG) anastomosis. Twelve consecutive patients referred for CABG with the use of anastomosis of the internal thoracic artery to the left anterior descending coronary artery (LAD) were studied. A linear 6.5-MHz wide-band transducer was used during cardioplegic administration and reperfusion. Baseline power Doppler signals were obtained in the LAD in 11 patients, and post-CABG signals were obtained in 11 patients. In one patient the LAD was poorly visualized because of extensive calcification. In another patient the flow after bypass worsened and the graft was revised. Visualization of the LAD and internal thoracic artery grafts by epicardial intraoperative power Doppler imaging is feasible in almost all patients and allows rapid and simple intraoperative assessment of graft patency. In addition, myocardial perfusion is limited by heavily calcified coronaries.

Comparison of intraoperative transesophageal echocardiographic examinations with the operative findings: prospective review of 1918 cases.

The purpose of this study was to prospectively compare the intraoperative transesophageal echocardiographic (IOTEE) findings with the operative findings in 1918 consecutive cardiac cases. Forty-eight discordant findings were found between the IOTEE and operative findings. Of the 48 discordant findings, most were related to valve pathology. Structural abnormalities that were missed by IOTEE included those of the aortic valve, 12 cases (25%), mitral valve, 13 cases (27%), and pulmonic and tricuspid valves, 5 cases (10%). Functional discrepancies occurred in 8% of cases. Overall, incidence of discrepant findings between IOTEE and operative findings was low (2.5%). This resulted in an alteration of the planned surgical procedure in a small number of cases (0.3%).

Role of emergency intraoperative transesophageal echocardiography.

Transesophageal echocardiography (TEE) has a definitive role in the diagnosis and management of critically ill patients with cardiovascular disease and patients undergoing cardiac operations. The diagnostic role of emergency intraoperative TEE and the impact on clinical outcome have not been evaluated. We reviewed the indications, findings, and impact of emergency intraoperative TEE in 66 patients over a 4-year period. The indications for emergency TEE were unexplained hemodynamic instability (36 patients), preoperative evaluation of patients having emergency surgery (19 patients), cardiac evaluation of trauma cases (6 patients), and unexplained intraoperative hypoxemia (5 patients). New findings were disclosed in 53 (80%) patients, with an alteration of the planned surgical procedure in 15 (23%). Despite the therapeutic impact, 24 patients (36%) did not survive to hospital dismissal. We recommend that TEE be considered as the diagnostic tool of choice when surgical patients have unexplained hemodynamic instability, when time does not permit complete preoperative evaluation, when cardiovascular injury is suspected in a trauma patient, and to evaluate unexplained hypoxemia.

Role of intraoperative transesophageal echocardiography in determining aortic annulus diameter in homograft insertion.

The sizing of aortic valve (AV) homografts for optimum function requires an accurate measurement of the aortic annulus. Typically, this measurement is obtained directly with sizers in the open aorta. We describe the use of intraoperative transesophageal echocardiography (IOTEE) to measure the aortic annulus and select the appropriate AV homograft before cardiopulmonary bypass and aortic cross-clamping. Thirty-two patients underwent AV homograft insertion between March 1993 and March 1996 and had IOTEE. There were 13 women and 19 men. Mean age was 58 +/- 14 years. IOTEE measurements were satisfactory in sizing in all patients, and no extraordinary surgical measures were necessary to insert the AV homografts. Early postoperative follow-up showed trivial or mild regurgitation of all homografts. Prebypass IOTEE is reliable in guiding the selection of optimal AV homografts.

Pericardial thickness measured with transesophageal echocardiography: feasibility and potential clinical usefulness.

OBJECTIVES: This study assessed the reliability of transesophageal echocardiographic measurements of pericardial thickness and the potential diagnostic usefulness of this technique. BACKGROUND: Transthoracic echocardiography cannot reliably detect thickened pericardium. The superior resolution achieved with transesophageal echocardiography should allow better pericardial definition. METHODS: Pericardial thickness measured at 26 locations in 11 patients with constrictive pericarditis who underwent intraoperative transesophageal echocardiography was compared with pericardial thickness measured with electron beam computed tomography. Intraobserver and interobserver variabilities were determined. Pericardial thickness was then measured in 21 normal subjects. With these values as a guide, two observers reviewed 37 transesophageal echocardiographic studies to determine whether echocardiographic measurement of pericardial thickness could be used to distinguish diseased from normal pericardium. RESULTS: The correlation between echocardiographic and computed tomographic measurements (r > or = 0.95, SE < or = 0.06 mm, p < 0.0001) was excellent. The +/-2 SD limits of agreement were +/-1.0 mm or less for pericardial thickness < 5.5 mm and +/-2.0 mm or less for the entire range of thicknesses. Intraobserver and interobserver agreements were good. Mean normal pericardial thickness was 1.2 +/- 0.8 mm (+/-2 SD) and did not exceed 2.5 mm. Pericardial thickness > or = 3 mm on transesophageal echocardiography was 95% sensitive and 86% specific for the detection of thickened pericardium. CONCLUSIONS: Measurement of pericardial thickness with transesophageal echocardiography is reproducible and should be a valuable adjunct in assessing constrictive pericarditis.

Correlation of regional wall motion abnormalities detected by two-dimensional echocardiography with perfusion defect determined by technetium 99m sestamibi imaging in patients treated with reperfusion therapy during acute myocardial infarction.

Twenty patients (13 men and 7 women; mean age 61 +/- 12 years) with > 30 minutes chest pain and new ST-segment elevation who were treated with reperfusion therapy underwent technetium 99m sestamibi imaging and two-dimensional echocardiography simultaneously before and within 2 hours of each test after acute reperfusion therapy. Nine patients had anterior wall myocardial infarction. Fifteen patients were initially treated with intravenous thrombolytic agents, and five patients underwent urgent percutaneous transluminal coronary angioplasty. Both myocardial perfusion defect and wall motion score index (WMSI) improved after reperfusion therapy (perfusion defect from 28% to 15%, WMSI from 1.68 to 1.45, respectively; p < 0.005). The overall correlation between WMSI and perfusion defect as a measure of myocardium at risk was significant during the acute phase (r = 0.71) and at hospital dismissal (r = 0.71). Thus myocardial perfusion defect and wall motion abnormalities correlated fairly well in patients with acute myocardial infarction during the acute phase and at predismissal study.

Role of transesophageal echocardiography in hemodynamically unstable patients.

OBJECTIVE: To evaluate the clinical impact of transesophageal echocardiography on subsequent management and outcome in hemodynamically unstable patients with suspected cardiovascular pathologic conditions. DESIGN: We reviewed data on patients with hemodynamic instability (hypotension, shock, or pulmonary edema) who underwent transesophageal echocardiography between December 1987 and May 1994. MATERIAL AND METHODS: A total of 127 patients (70 male and 57 female patients with a mean age of 68 years) underwent transesophageal echocardiography at our institution as part of the diagnostic procedures used to evaluate unstable hemodynamics. RESULTS: No clinically significant complication was encountered during the procedure; transesophageal echocardiographic imaging was inadequate in three patients (2%). Of the 124 patients with adequate images, transesophageal echocardiography disclosed a severe cardiovascular abnormality responsible for the unstable hemodynamics in 65 patients (52%), and 26 patients (21%) underwent urgent pericardiocentesis or a cardiac surgical procedure, primarily based on transesophageal echocardiographic findings. CONCLUSION: Transesophageal echocardiography can be safely performed in hemodynamically unstable patients, it produces a high diagnostic yield, and it provides important information for prompt therapeutic decision making. Therefore, we recommend transesophageal echocardiography as one of the initial diagnostic procedures in critically ill patients suspected of having an underlying cardiovascular disorder.

Congenital absence of the pericardium: echocardiography as a diagnostic tool.

Between 1982 and 1992, 10 patients who underwent echocardiography at the Mayo Clinic were found to have congenital absence of the pericardium. Clinical, electrocardiographic, chest roentgenographic, echocardiographic, computed tomographic, and magnetic resonance imaging features were reviewed in this patient group. The characteristic features of this entity are reviewed. The echocardiographic features in order of frequency are (1) unusual echocardiographic windows, seen in all 10 patients, (2) cardiac hypermobility in nine patients, (3) abnormal ventricular septal motion in eight patients, and (4) abnormal swinging motion of the heart in seven patients.

Prospective evaluation of the risk of bacteremia associated with transesophageal echocardiography.

BACKGROUND: Transient bacteremia may lead to endocarditis in patients with significant valvular lesions. METHODS AND RESULTS: Because transesophageal echocardiography selects a patient population with a high prevalence of valvular lesions, we prospectively evaluated the risk of transient bacteremia associated with transesophageal echocardiography in 49 patients. Blood cultures were obtained immediately before transesophageal echocardiography and at 5, 10, and 20 minutes after the start of the procedure. For each culture, 30 ml venous blood was obtained and 10 ml was inoculated into each of an Isolator tube, Septi-chek bottle, and a nonvented Trypticase soy broth bottle. Broth cultures were incubated for 14 days. Blood from the Isolator tube was plated onto appropriate media for recovery of bacteria and fungi. Two patients were excluded from analysis because the final two sets of blood cultures could not be obtained. Among the remaining 47 study patients, two preprocedure control blood cultures were positive, and two of 141 subsequent cultures were positive. All isolates were considered contaminants. Thus, we found no significant bacteremia due to pathogenic oral flora during transesophageal echocardiography (0%; 95% CI, 0.0-7.5%). CONCLUSIONS: Although recommendations for antimicrobial prophylaxis for transesophageal echocardiography should be individualized for each patient, many patients may not require antimicrobial prophylaxis.

Tissue characterization of an unusual right atrial mass by magnetic resonance imaging.

In a 70-year-old man who had angina, exercise-induced ventricular tachycardia, and presyncopal symptoms, transthoracic and transesophageal echocardiography disclosed a large atrial mass that resembled a myxoma. Subsequent evaluation by magnetic resonance imaging identified the mass as an intracardiac lipoma attached to the posterior wall of the right atrium, a diagnosis that was confirmed by surgical intervention. Thus, the diagnostic utility of magnetic resonance imaging as an adjunct to echocardiographic evaluation of intracardiac masses was demonstrated.

Elevation of plasma endothelin associated with systemic hypertension in humans following orthotopic liver transplantation.

Endothelin (ET) is a 21-amino-acid peptide of endothelial origin, is a potent systemic and renal vasoconstrictor associated with sodium retention and modulation of the renin-angiotensin-aldosterone system. The present study was designed to determine if plasma ET is elevated in humans with cirrhosis (n = 12), a state characterized by sodium retention and increased plasma renin activity (PRA) and plasma aldosterone (PA), and to determine the effect of orthotopic liver transplantation (OLT) upon plasma ET, PRA, and PA at 1, 3, and 7 days after transplantation. Plasma ET before OLT was 1.62 +/- 0.23 pg/ml, which was not different as compared with normal controls. Plasma ET significantly increased to 4.18 +/- 0.66, 3.87 +/- 0.58, and 4.07 +/- 0.61 pg/ml, respectively following OLT. PRA remained elevated throughout the postoperative course, in contrast to PA that decreased following OLT. Mean arterial pressure increased significantly from 82 +/- 4 pre-OLT to 98 +/- 4 and 103 +/- 2 mmHG on days 3 and 7 respectively.

Complement activation from protamine sulfate administration after coronary angiography.

The cause of hypotension after reversal of heparin by protamine has not been well defined. In this study we evaluated complement activation (C3a and C4a) by the heparin-protamine complex in 46 consecutive patients (40 received protamine sulfate to reverse heparin, and six did not) during and after coronary angiography. In patients receiving protamine sulfate, there was a significant increase in C3a over the value before protamine sulfate administration (P less than .001) or in patients who did not receive protamine sulfate (P less than .05): 807 +/- 100 ng/ml vs. 274 +/- 75 ng/ml. There were no significant changes in C4a after protamine sulfate administration. These results indicate that the alternate complement pathway is activated when protamine sulfate is administered after coronary angiography. This may induce hypotension as well as platelet aggregation and thrombus formation and may contribute to coronary instability. Therefore, in unstable patients, heparin reversal by protamine should not be done routinely.