Intraoperative role of trans-oesophageal echocardiography in mediastinal tumour surgery

Sir,

We report a case of a 41-year-old gentleman, who presented to our out-patient department with the history of dry cough for past 7 months. Chest computed tomography (CT) showed a large well-defined irregular heterogeneous mass lesion of size 10.5 × 12.7 × 9.4 cm in the anterior mediastinum. Few enlarged necrotic Delphian, pretracheal, and prevascular lymph nodes, the largest measured 3.0 × 1.9 cm, were noted. Ultrasound-guided biopsy was suggestive of an atypical myxoid neoplasm, and the immunohistochemistry (IHC) was consistent with pleomorphic undifferentiated sarcoma. Based on the tumour board decision, 3 cycles of neoadjuvant chemotherapy was given and re-evaluated; it showed no reduction in the size of the tumour. Positron emission tomography showed a primary lesion in the mediastinum with no evidence of distant disease. There were indeterminate planes between the mass and ascending aorta, aortic arch, main pulmonary artery and doubtful involvement of superior vena cava (SVC), right branch of pulmonary artery, right atrium, and right superior pulmonary veins (SPV) (Fig. 1). En bloc resection of the mass along with SVC resection and reconstruction was planned. With cardiopulmonary bypass (CPB) on standby, under general anaesthesia with single lumen intubation, the femoral vessels were exposed prior to midline sternotomy. After pericardiotomy, mass was mobilized with pericardial reflection and was retracted and separated from the ascending aorta and the SVC. To determine the planes of dissection between the mass and extra-pericardial portion of the SVC and right SPV, a trans-oesophageal echocardiography (TOE) was performed which revealed no involvement of the SVC, right atrium, and SPV (Fig. 2). After entering the right pleural space, tumour was further mobilized from SPV and excised in toto. Post-operative histopathology with IHC was that of pleomorphic undifferentiated sarcoma with clear margins. He had an uneventful recovery.

Fig. 1.

Computed Tomography of Chest showing Indeterminate planes between the mass, SVC and SPV

Fig. 2.

Transoesophageal Echocardiography showing distinct planes between the mass, right atrium, SVC, SPV

Mediastinal masses compressing the heart or great vessels require complete assessment prior to surgery regarding extent of compression or encroachment, for complete and safe removal and for the requirement of CPB [1]. Magnetic resonance imaging and CT are essential for assessment of staging, extent and resectability of the mass. TOE can provide information regarding encroachment and compression [1]. TOE is more accurate than transthoracic echocardiography in detecting mediastinal masses (90% versus 73%), in identifying their structure (100% versus 90%), and in evaluating their relationship with contiguous organs (89% versus 81%) [2]. Every surface and border of the heart cannot be delineated by TOE; however, real-time images may provide evidence of mediastinal pleural sliding, which may help to exclude tumour invasion to the surrounding structures. During the manipulation of the mass, real-time TOE guides anaesthesiologist in optimizing the hemodynamic stability [3]. The chest cavity does not have space to expand; hence, large mediastinal masses cause compression, displacement, and encroachment of vital structures [3]. As in our case, the anterior mediastinal mass was causing compression/encroaching the SVC, SPV with indeterminate plane on the contrast CT scan; hence, intraoperative TOE after decompression of the chest was done, which revealed planes between mass and the SVC and SPV without any involvement, which aided in the complete resections and negated the use of a CPB in this patient.

Funding

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Declarations

Human and animal rights

All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. This article does not contain any studies with animals performed by any of the authors.

Informed consent

Informed consent was obtained as per institutional ethics committee guidance.

Conflict of interest

The authors declare no competing interests.