Left Atrial Appendage... and Another Appendage? Khurram Owais, MD,* Mario Montealegre-Gallegos, MD,*† Robina Matyal, MD,* Anam Pal, MD,‡ and Feroze Mahmood, MD*
66-year-old man (1.63 m, 71.8 kg) was scheduled to undergo elective coronary artery bypass graft surgery and mitral valve repair. Before cardiopulmonary bypass, a transesophageal echocardiography (TEE) examination found an
Fig 1. An outpouching of the left atrial wall (arrow) is seen with 2D transesophageal echocardiography in the mid-esophageal longaxis view.
Fig 3. En face view of the mitral valve obtained with 3D transesophageal echocardiography. The left atrial appendage is seen at the 9 o’clock position, while an outpouching of the left atrial wall also is seen (4 o’clock) in close proximity to the P3 scallop of the posterior leaﬂet of the mitral valve (arrowhead). Abbreviations: AV, aortic valve; LAA, left atrial appendage.
outpouching of the left atrium in the mid-esophageal long-axis view (Fig 1, Video clip 1). Three-dimensional (3D) imaging of the structure from the mid-esophageal window also demonstrated an outpouching of the left atrium adjacent to the P3 scallop of the mitral valve (Fig 2, Video clip 2). In the en face view of the mitral valve, the left atrial appendage was visualized at the 9 o’clock position and the outpouching was visualized at 4 o’clock (Fig 3, Video clip 3). What is the diagnosis?
Fig 2. 3D transesophageal echocardiography image showing the outpouching of the left atrial wall (arrow) close to the P3 scallop of the mitral valve. Abbreviations: LV, left ventricle; LA, left atrium).
From the *Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School Boston, MA, †Servicio de Anestesiología Hospital México C.C.S.S., Universidad de Costa Rica, San José, Costa Rica; and ‡Division of Cardiac Surgery, Department of Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA. Address reprint requests to Feroze Mahmood, MD, Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215. E-mail: [email protected]
© 2014 Elsevier Inc. All rights reserved. 1053-0770/2602-0033$36.00/0 http://dx.doi.org/10.1053/j.jvca.2014.06.027
Journal of Cardiothoracic and Vascular Anesthesia, Vol 29, No 1 (February), 2015: pp 248–249
LEFT ATRIAL APPENDAGE... AND ANOTHER APPENDAGE?
DIAGNOSIS: LEFT ATRIAL DIVERTICULUM
The 2D and 3D imaging (Figs 1–3, Video clips 1–4) showed the presence of a left atrial diverticulum. These diverticula usually are reported as incidental ﬁndings (Fig 3, Video clip 4).1 They are potential sources of thromboembolism2 or sites of catheterentrapment with risk of left atrium perforation during radiofrequency ablation.3 These diverticula are relatively common and traditionally have been noted using computed tomography scanning.4 The majority of reports of left atrium diverticula are based on cardiac computed tomography studies for ablation procedures or coronary angiography.5 Despite their relatively common occurrence, there are only a few reports of echocardiographic visualization of left atrium diverticula.2,6 These reports are based on 2D echocardiographic images. The current case illustrated an incidental left atrium diverticulum seen during a routine mitral valve repair procedure. 3D TEE (live and reconstruction) revealed a small outpouching of the endocardial wall
near the P3 segment of the mitral valve leaﬂet on an en face view.7 Doppler examination of the diverticulum did not demonstrate any ﬂow with pulse-wave or color-ﬂow Doppler. During exposure of the mitral valve for surgical repair, the endocardial outpouching was conﬁrmed surgically, which did not warrant any surgical intervention. The current case shows the utility of 3D TEE to accurately and dynamically visualize the presence, location, and surrounding anatomy of atrial diverticula. Although a possible diverticulum was appreciated with 2D imaging, 3D images of the mitral valve and left atrium showed more spatial information. 3D images also can be analyzed using multiplanar reformatting to obtain orthogonal views to further delineate geometry, if required (Video clip 5). APPENDIX A. SUPPORTING INFORMATION
Supplementary material cited in this article is available online at doi:10.1053/j.jvca.2014.06.027.
REFERENCES 1. Shin SY, Kwon SH, Oh JH: Anatomical analysis of incidental left atrial diverticula in patients with suspected coronary artery disease using 64-channel multidetector CT. Clin Radiol 66:961-965, 2011 2. Nagai T, Fujii A, Nishimura K, et al: Large thrombus originating from left atrial diverticulum: a new concern for catheter ablation of atrial ﬁbrillation. Circulation 124:1086-1088, 2011 3. Gonçalves A, Marcos-Alberca P, Zamorano JL: Left atrium wall diverticulum: An additional anatomical consideration in atrial ﬁbrillation catheter ablation. Eur Heart J 30:2164, 2009
4. Abbara S, Mundo-Sagardia JA, Hoffmann U, et al: Cardiac CT assessment of left atrial accessory appendages and diverticula. AJR Am J Roentgenol 193:807-812, 2009 5. Peng L-Q, Yu J-Q, Yang Z-G, et al: Left atrial diverticula in patients referred for radiofrequency ablation of atrial ﬁbrillation: assessment of prevalence and morphologic characteristics by dual-source computed tomography. Circ Arrhythm Electrophysiol 5:345-350, 2012 6. Herzog BA, Husmann L, Jenni R, et al: Diverticulum of the posterior left atrial wall. Echocardiography 26:471-472, 2009 7. Mahmood F, Warraich HJ, Shahul S, et al: En face view of the mitral valve: Deﬁnition and acquisition. Anesth. Analg. 115:779-784, 2012