Carbon Dioxide Angiography in the Treatment of Transplant Renal Artery Stenosis

Abstract Objectives Transplant renal stenosis (TRAS) is a serious complication associated with graft loss. Selective carbon dioxide angiography allows for effective diagnosis and therapy with the use of minimal to no contrast agent. This study sought to evaluate the efficacy of the adjunctive use of carbon dioxide angiography in the treatment of TRAS. Methods Patients undergoing endovascular therapy (percutaneous transluminal angioplasty with or without stent) for TRAS between the years 2012 and 2017 at a single tertiary care academic medical center were studied. Outcomes of interest included technical success, post-operative glomerular filtration rate (GFR), and renal ultrasound hemodynamic parameters. Results Of the 37 patients who underwent angiography for TRAS during the study period, 34 underwent a therapeutic intervention. Of those, 24 patients (70.6%) underwent adjunctive carbon dioxide angiography vs. 10 patients (29.4%) who underwent standard contrast angiography. Baseline characteristics between the carbon dioxide angiography and traditional angiography groups were similar. Patients undergoing carbon dioxide angiography received significantly less contrast agent than patients undergoing traditional angiography [9.5 ml (IQR 2-19.5) vs. 19.5 ml (IQR 15-30)], p =0.03)] and maintained equivalent technical success rates (92.2% vs. 91.7%, p=0.9). Conclusions The adjunctive use of carbon dioxide angiography allows for significantly less contrast administration compared to standard angiography while achieving an equivalent rate of technical success. Selective carbon dioxide angiography should be considered a first line modality for patients with TRAS in need of endovascular therapy.