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case_images: Transthoracic echocardiography. (A) Apical four-chamber view shows marked dilation of the right atrium (LA) and right ventricle (RV). (B) Short-axis view shows dilation of the right ventricle and flattening of the interventricular septum in systole.
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case_images: Electrocardiogram (ECG) showed sinus rhythm, borderline right axis deviation (+90 ), and S1Q3T3 pattern (see Supplementary material online, Figure S1).
case_images: Angiotomography of great vessels and MRI of the thorax. Severe obstruction of the right (A) and left (arrows) (B) pulmonary arteries is evident. Chest magnetic resonance. (C) Scar tissue is observed in the superior mediastinum that involves branches of the right and left pulmonary arteries (asterisks).
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case_images: TRV (tricuspid valve regurgitation) 4 m/s, and PASP (pulmonary artery systolic pressure) 85 mmHg with evidence of supravalvular stenosis (see Supplementary material online, Figure S2). There was no evidence of carcinoid valvulopathy, but there was tricuspid annular dilation. Cardiac tomography confirmed extrinsic compression (Figure 2A and B). MRI (magnetic resonance image) of the thorax showed signs of mild fibrotic changes in the anterior and middle mediastinum with vascular compromise without evidence of a mediastinal mass (Figure 2C).
case_images: Fluorodeoxyglucose positron emission tomography. Hypermetabolism (asterisks) is observed in irregular lamellar tissue surrounding great vessels (A) and the heart (B).
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case_images: Given the suspicion of a possible neoplasia in the area showing metabolic activity on FDG-PET (Figure 3), pleural biopsy was performed via thoracoscopy.
case_images: Venous angiography. (A) shows total obstruction at the level of the superior vena cava and the innominate vein (asterisks). (B) Balloon dilation at the level of the innominate vein. Three-dimensional reconstruction of cardiac computed tomography. (C) Image shows stent in the right pulmonary artery (RPA) and innominate vein (IV). (D) A stent is evident in the left pulmonary artery (LPA) and IV.
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case_images: During hospitalization, the patient developed superior vena cava syndrome, prompting a venography that was performed that revealed a total obstruction of the superior vena cava before its junction with the azygos vein and the innominate vein (Figure 4A). The flow in the left innominate vein was restored through percutaneous transluminal balloon dilation (Figure 4B).
case_images: Chest computed tomography. (A) A 70% stenosis of the left bronchus lumen is observed (arrow). (B) Anterior mediastinal mass with bone and right ventricular involvement (asterisk). Pathological anatomy. (C) Haematoxylin eosin stain shows pericardial tissue infiltrated by well-differentiated neuroendocrine tumour nests. (D) Immunohistochemistry is positive for synaptophysin. (E) Proliferation index with Ki-67 of 20%.
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case_images: The patient was discharged and followed up as an outpatient with chest computed tomography scan after 18 months, which showed adequate patency of the stents but revealed 70% obstruction of the left bronchus (Figure 5A). Additionally, an anterior mediastinal mass was identified (Figure 5B), prompting hospitalization for a biopsy (Figure 5C-5E), which revealed the following immunohistochemistry results: chromogranin: positive, synaptophysin: positive, pankeratin: positive, CD45: negative, and Ki-67: 20%.