Acute superior vena cava collapse after thymic carcinoma resection and failed pericardial bypass rescued by endovascular stenting: a case report

Thymic carcinoma with superior vena cava (SVC) invasion is challenging. Intraoperative acute SVC syndrome may result from extrinsic compression after venous reconstruction. Intraoperative acute superior vena cava collapse due to extrinsic compression following thymic carcinoma resection and venous reconstruction appears to be infrequently reported and offers important insights into graft selection and rescue strategies. A 77-year-old woman with stage III thymic squamous cell carcinoma achieved partial response after cisplatin/nab-paclitaxel with camrelizumab. Resection included stapled SVC venoplasty; during chest closure, central venous pressure (CVP) surged to 40 mmHg. An autologous pericardial bypass between the right innominate vein and right atrium temporarily normalized CVP, yet a second CVP spike occurred after re-closure. Angiography revealed severe proximal SVC narrowing consistent with extrinsic compression. Immediate endovascular stenting with sequential balloon dilations restored patency and stability. When autologous pericardial bypass collapses under extrinsic compression, immediate endovascular stenting provides a rational, time-critical rescue to re-establish SVC flow. Recognizing mechanical causes of collapse and anticipating external pressure can guide graft selection and intraoperative decision-making.