How to cite this article: Gadhinglajkar S, Sreedhar R. Intraoperative evaluation of left atrial myxoma using real-time 3D transesophageal echocardiography. Ann Card Anaesth 2010;13:180-1
How to cite this URL: Gadhinglajkar S, Sreedhar R. Intraoperative evaluation of left atrial myxoma using real-time 3D transesophageal echocardiography. Ann Card Anaesth [serial online] 2010 [cited 2022 Jan 29];13:180-1. Available from: https://www.annals.in/text.asp?2010/13/2/180/62937
Real-time 3D transesophageal echocardiography (RT-3D-TEE) is a new technology available in ultrasound machine I/E 33 (Philips medical systems, Bothell, WA, USA). We used this technology during surgery for myxoma of left atrium (LA). A 21-year-old female patient presented to us with dyspnea on exertion New York heart association (NYHA) class III, since one year with orthopnea. Preoperative transthoracic echocardiography (TTE) diagnosed the presence of a LA myxoma measuring 36 mm X 28 mm in size and attached to interatrial septum (IAS), along with moderate pulmonary hypertension. After induction of anesthesia, heart was inspected using the RT-3D-TEE. Live and full volume acquisition of 3D images revealed the LA myxoma protruding into left ventricle (LV) during diastole. Frontal plane sections taken at different sequential levels demonstrated isolated echolucencies within the tumor [[Figure 1], [Video 1]- . When the tumor was visualized in en-face view from LA, it was seen attached to the IAS. Virtual left atriotomy at its mid portion revealed the tumor occupying almost 70% of the LA cavity. Diastolic protrusion of the myxoma across mitral valve created mitral stenosis like effect, although the mitral valve was structurally normal. Transmitral diastolic blood flow was seen occurring predominantly near the posterior mitral leaflet [Figure 2]. Effective mitral valve area (calculated by pressure half-time method) and transmitral mean diastolic pressure gradient were 0.98 cm2 and 12 mmHg respectively. Pulmonary artery systolic pressure measured from TR jet was 66 mmHg. Three dimensional volumetric tumor measurements were performed by area-length method using QLAB quantification software (QLAB, Philips Ultrasound) after full-volume acquisition. Measured volumes in biplanes were averaged to derive the virtual tumor volume, which was 36.59cm 3 . After establishment of cardiopulmonary bypass and cardioplegic arrest, the tumor was completely excised. Patient was weaned from CPB successfully and subsequently had an uneventful recovery. The tumor volume measured directly with water displacement method was 40.5 ml. The cut section of the surgical specimen revealed necrotic areas in the tumor mass as seen on 3D images. Postoperative histopathological evaluation confirmed that the tumor was a myxoma.
The currently only clinically available RT-3D-TEE transducer is the X7-2t TEE transducer, which combines xMATRIX technology and PureWave crystal technology. The system offers Live-3D, 3D-zoom, Full volume-3D and 3D-color full volume modes. Live x-plane imaging creates two full resolution planes simultaneously. RT-3D-TEE permits the acquisition of the entire tumor mass from any ultrasound window with less dependence on the acquirer's persistence. The acquired pyramidal volume of information can be visualized from different angles and cropped on any desired plane to focus on any region of interest contained in the volume.
RT-3D-TEE has ability to demonstrate tumor characteristics in its en-face view, which may be more convincingly appreciated by the operating surgeon than the 2D imaging. It facilitates understanding of attachments of the myxoma to different parts of the LA; structural damage to the mitral valve; and degree of free space available for blood flow inside the LA and across the mitral valve.
Isolated echolucent areas observed on live RT-3D-TEE are consistent with hemorrhage/necrosis in the tumor mass. These findings are typical of a myxoma and the areas of echolucencies correspond to tumor hemorrhages and/or necrosis found on pathological examination of the resected myxomas. This echocardiographic feature of a LA myxoma may be utilized to differentiate it from a hemangioma, which comprises much more extensive and closely packed echolucencies practically involving the whole extent of the tumor mass with relatively sparse solid tissue. Virtual cropping at different sequential levels in the three-dimensional data set enabled us to demonstrate echolucencies, which was not possible on 2D examination.
Major limitations of 2D echocardiography (both TTE and TEE) in examining the LA myxoma are difficulty in evaluating it from all possible planes and operator dependent interpretations of the findings. 2DE measurements underestimate the true maximum diameter and tumor size of irregularly shaped intracardiac tumors like LA myxoma. Although, there are reports suggesting utility of RT-3D-TEE in volumetric assessment of LA myxomas;, it has not yet been validated like RT-3d-TTE. Virtual volume estimated using RT-3D-TEE in those reported cases was comparable to the volume measured with the gold standard water displacement. The size of an intracardiac mass (vegetation, tumor, or thrombus) is an important predictor for embolic events and for response to treatment.
In summary, the intraoperative RT-3D-TEE has a potential role to play in the assessment of LA myxoma.
Mehmood F, Nanda NC, Vengala S, Winokur TS, Dod HS, Frans E, et al. Live three-dimensional transthoracic echocardiographic assessment of left atrial tumors. Echocardiography 2005;22:137-43. [PUBMED] [FULLTEXT]