Approximately 3 hours into the preanhepatic dissection, his systolic blood pressure decreased steadily over 10 minutes to 60 to 70 mm Hg. Significant hypotension (mean arterial blood pressure=30–40 mm Hg) and tachycardia (heart rate=90 bpm) continued despite fluid boluses, phenylephrine, and retractor adjustment. TEE examination of the ME 2-chamber (2C) and ME 4-chamber (4C) views showed a 4 × 5 cm mass between the aorta and the left atrium (LA) at the level of the pulmonary veins with near complete obliteration of the LA (Figs. 2 and 3) (Video 1, see Supplementary Digital Content 1, http://links.lww.com/AA/A279; see Appendix for video captions). The mass appeared to have an air-fluid level (Video 2, see Supplementary Digital Content 2, http://links.lww.com/AA/A280). Because of mass encroachment of the LA, TEE visualization of the left upper pulmonary vein or right upper pulmonary vein was not possible. Color Doppler analysis of the mitral valve in the ME 4C, ME 2C, and ME long-axis (LAX) views did not reveal any significant mitral regurgitation.
Intraoperative endoscopy revealed a massively dilated esophagus (40 cm) consistent with achalasia and several large food particles. Based on the TEE findings, the subcostal retractors were removed and abdominal contents returned to their anatomic positions. Shortly after this maneuver, the LA returned to normal size and appearance on TEE examination (Video 3, see Supplementary Digital Content 3, http://links.lww.com/AA/A281). Pulmonary vein flow obtained with pulse-wave Doppler in the left upper pulmonary vein was systolic dominant and the patient was easily weaned off vasopressors. Revascularization of the organs was successful. The TEE probe was removed without difficulty and was clear of debris.
This is the first case report to demonstrate the value of TEE to rapidly identify LA obstruction due to surgical maneuvering of a food-filled esophagus with subcostal retractors. Although case reports have described posterior mediastinal masses diagnosed by echocardiography, none were diagnosed intraoperatively by TEE due to achalasia.1,2 In limited studies, TEE has been shown to be comparable to computed tomography or magnetic resonance imaging in diagnosing compression of cardiac chambers by posterior mediastinal masses, but only TEE can be used intraoperatively.3 In this case, the acute alteration in blood pressure was attributable to the esophagus compressing the LA and pulmonary veins, and could not have been diagnosed without the continuous monitoring of this region by TEE. The LA's posterior anatomic position and low intracardiac pressure make it a common site for encroachment by masses of the posterior mediastinum, although left ventricular encroachment has been reported. Unlike posterior mediastinal masses, anterior mediastinal masses typically compress right heart chambers, as published previously in Echo Rounds by Redford et al.4
Posterior mediastinal masses are found on TEE in the following positions: lateral to the LA in the ME 4C view, inferior to the LA in the ME 2C view, and posterior to the LA in the ME LAX view. The transgastric 2C view or transgastric LAX view can also depict posterior mediastinal masses seen inferiorly. Aortic dissections or aneurysms, lung masses, and loculated pericardial effusions may all be mistaken for posterior mediastinal masses. A method of differentiating these from an esophageal mass would be injecting a small quantity of carbonated solution through a nasogastric tube, resulting in contrast enhancement of the mass.5 However, in this case, it was not necessary because of the high index of suspicion raised by the preoperative TEE findings and the rapid resolution of hemodynamic instability with release of the retractors.
Patients presenting for liver transplantation often have diseases of the esophagus, which can make TEE monitoring difficult. Recent guidelines published by the American Society of Anesthesiology and the Society of Cardiovascular Anesthesiology on the use of perioperative echocardiography state that there is inconclusive literature to assess whether there are absolute contraindications to TEE.6 Some experts agree there are 4 contraindications to TEE: esophageal stricture, tracheoesophageal fistula, postesophageal surgery, and esophageal trauma.6 We had no difficulty in probe placement, manipulation, or acquisition of TEE views. Traditional ME TEE views were obtained at normal omniplanes, which may have been difficult given the diameter of the esophagus and debris present. Because there was minimal air in the esophagus, sound transmission was not hindered. More importantly, TEE aided in the rare diagnosis of intraoperative compression of the LA by the food-filled esophagus and resulted in rapid corrective measures that permitted the liver transplantation to occur.
Name: Sasha K. Shillcutt, MD, FASE.
Contribution: This author helped conduct the study and write the manuscript.
Attestation: Sasha K. Shillcutt approved the final manuscript.
Name: Ellen K. Roberts, MD.
Contribution: This author helped write the manuscript.
Attestation: Ellen K. Roberts approved the final manuscript.
1. D'Cruz IA, Feghali N, Gross CM. Echocardiographic manifestations of mediastinal masses compressing or encroaching on the heart. Echocardiography 1994; 11: 523–33
2. Mates M, Veselka J, Belohlavek J. Esophageal achalasia compressing the heart diagnosed by echocardiography. Int J Cardiol 1998; 66: 225–7
3. Faletra F, Ravini M, Moreo A, Fedriga E, Ciliberto MR, Alberti A, Roverato S, Belloni PA. Transesophageal echocardiography in the evaluation of mediastinal masses. J Am Soc Echocardiogr 1992; 5: 178–86
4. Redford DT, Kim AS, Barber BJ, Copeland JG. Transesophageal echocardiography for the intraoperative evaluation of a large anterior mediastinal mass. Anesth Analg 2006; 103: 578–9
5. Gupta M, Nanda NC, Inamdar V. Two- and three-dimensional transthoracic echocardiographic assessment of hiatal hernia. Echocardiography 2008; 25: 790–3
6. Thys DM, Abel MD, Brooker RF, Cahalan MK, Connis RT, Duke PG, Nickinovich DG, Reeves ST, Rozner MA, Russell IA, Streckenbach SC, Sears-Rogan P, Stewart WJ. Practice guidelines for perioperative transesophageal echocardiography: an updated report by the American Society of Anesthesiologists and the Society of Cardiovascular Anesthesiologists task force on transesophageal echocardiography. Anesthesiology 2010; 112: 1–11
APPENDIX: LEGENDS FOR THE ONLINE ECHOCARDIOGRAPHIC STILL AND VIDEO IMAGES
Video 1. Midesophageal 2-chamber view showing compression of the left atrium (LA) by a solid food mass in the esophagus, which mimicked a posterior mediastinal mass after placement of subcostal retractors. LV=left ventricle.
Video 2. Midesophageal 4-chamber views showing the solid food mass compressing the left atrium (LA). Arrow depicts air-fluid levels in the heterogeneous densities of the mass lesion. RA=right atrium; RV=right ventricle; LV=left ventricle.
Video 3. Composite clip of midesophageal 2-chamber, midesophageal long-axis and deep gastric 5-chamber views depicting a normal-appearing left atrium (LA) seen after removal of the surgical retractors. The patient was hemodynamically stable without the mass effect of the food bolus compressing the LA. LV=left ventricle; Ao=aorta; RA=right atrium; RV=right ventricle.
Clinician's Key Teaching Points By Nikolaos J. Skubas, MD, Roman M. Sniecinski, MD, and Martin J. London, MD
- Achalasia affects the smooth muscles of the esophagus and lower sphincter, decreasing normal peristalsis and increasing sphincter tone. This leads to a dilated esophagus, often containing retained food, which may present as a posterior mass behind the left atrium (LA). Esophageal achalasia is not considered a contraindication to a transesophageal echocardiogram (TEE) imaging.
- Posterior mediastinal masses are generally diagnosed with computed tomography or magnetic resonance imaging and include aortic aneurysms and dissection and loculated pericardial effusions. With TEE imaging, these masses are imaged adjacent to the LA in the midesophageal (ME) views (lateral in 4C, inferior in 2C and posterior in long-axis) and inferiorly in the transgastric views.
- In this case of liver, pancreas and small intestine transplantation, TEE imaging was used for hemodynamic monitoring. Acute hypotension occurred during hepatic dissection and was unresponsive to vasoactive treatment. The ME views on TEE imaging showed compression of the LA and pulmonary veins by an extrinsic mass, presumably shifted by placement of surgical retractors subcostally. The presence of several air-fluid levels in the mass identified it as the patient's dilated esophagus.
- In esophageal achalasia echocardiographic imaging is difficult because of poor contact of the TEE probe with the wall due to food particles and air, which does not permit transmission of ultrasound waves. Proper suctioning of the esophagus and stomach before probe placement is important. Injection of a small quantity of carbonated fluid through a nasogastric tube will increase the echogenicity of the dilated esophagus and differentiate it from a posterior mediastinal mass.
Supplemental Digital Content
© 2011 International Anesthesia Research Society