Bronchogenic cyst is a rare congenital malformation of the bronchial tree with a reported prevalence of 1 per 68 000 admissions in one hospital series. It is often found incidentally on cross-sectional imaging and rarely causes life-threatening compressive symptoms. We here present a case of massive mediastinal bronchogenic cyst requiring emergency endoscopic ultrasound (EUS)-guided decompression.

A 22-year-old male patient presented with 1-week history of progressive breathlessness and chest pain. Urgent computed tomography thorax showed a 10-cm cystic lesion in the middle mediastinum compressing the left main bronchus and superior pulmonary vein causing heart failure and post obstructive pneumonia (Fig. 1). Patient was assessed by the anesthesia team and was deemed unfit to proceed to surgical removal of the cyst under general anesthesia due to compromised cardiopulmonary status. EUS-guided aspiration was performed under conscious sedation as a bridge to surgery. Midazolam and pethidine were titrated up gradually, and a total dose of 5 and 25 mg, respectively, were used. Procedure had to be performed at 30° prop up position with 3 L of oxygen supply via nasal cannula to avoid hypoxemia. Blood pressure was 128/63, pulse was 78, and oxygen saturation was 99% at the beginning of the procedure. Linear echoendoscope demonstrated a large anechoic well-defined 6.4 cm × 4 cm cystic structure between the esophagus, heart, and ascending aorta, compressing on the left atrium, ascending aorta, and pulmonary artery (Fig. 2). A 19-G needle was inserted into the cystic structure, and 140-mL viscous fluid was aspirated. The cyst immediately collapsed with relief of mass effect (Fig. 3). The procedure took 20 min to complete, and no infective or bleeding complications were reported. Follow-up computed tomography on Day 6 showed resolution of previous lung consolidative changes (Fig. 4). He underwent video-assisted thoracotomy and de-roofing of the mediastinal cyst 1 month later.

Urgent computed tomography thorax: cystic lesion without rim enhancement at middle mediastinum, compressing the left main bronchus and superior pulmonary vein. SVC, superior vena cava; PV, pulmonary artery.

A large anechoic well-defined 6.4 cm × 4 cm cystic structure between the esophagus, heart, and ascending aorta seen, compressing on the left atrium, ascending aorta, and pulmonary artery.

Immediate relief of mass effect after 140 mL of viscous fluid was aspirated.

Repeat computed tomography scan showed resolution of previous lung consolidative changes.

This case has demonstrated that emergency EUS-guided aspiration of a bronchogenic cyst is a feasible and safe option particularly in patients who are hemodynamically unstable for traditional surgery under general anesthesia.