Carbon Dioxide Digital Subtraction Angiography for Central Venous Recanalization in a Kidney Transplant Patient: A Case Report.

Background: We present the case of a kidney transplant recipient with elevated serum creatinine who developed left upper limb swelling due to left subclavian vein thrombosis. Concerned about potential hemodialysis resumption, the patient prioritized preserving their arteriovenous fistula.

Methods: To address the swelling and maintain fistula function, central venous recanalization was necessary. Given the risk of iodine contrast-induced acute kidney injury, particularly with elevated creatinine, the patient opted for carbon dioxide (CO₂) angiography. Following forearm fistula puncture, a catheter was inserted, and 50 mL of CO₂ was injected. Angiography revealed a left subclavian vein filling defect and stenosis, preventing guidewire passage. The stenosis was dilated using an 8 mm × 20 mm balloon, followed by implantation of a 6 mm × 10 mm vascular stent. Postintervention CO₂ angiography confirmed successful vein opening. Oral rivaroxaban was prescribed for anticoagulation.

Results: The patient's limb swelling gradually resolved, and serum creatinine remained stable.

Conclusion: CO₂-DSA represents a potentially viable alternative imaging modality for patients requiring vascular interventions who are at elevated risk of iodinated contrast-induced nephropathy.