Comparative study of transcatheter renal arterial embolization with and without closed renal circuit: pharmacokinetic and histologic assessment in pigs.

Objective: To assess the degree of renal necrosis and the leakage of absolute ethanol by using two

Methods: transcatheter renal artery embolization (TAE) and TAE performed with a closed renal circuit (CRC) (TAE/CRC), both performed by using ethanol and iodized oil, in a pig model. Methods: All animal experiments were conducted in accordance with our university guidelines for animal care and experimentation. Fourteen pigs were classified in two groups: standard TAE and TAE/CRC groups. In the TAE/CRC group, the renal artery and vein were occluded with balloon catheters; in the TAE group, only the renal artery was occluded. An emulsion of absolute ethanol (0.5 mL per kilogram of body weight) and iodized oil (emulsion ratio, 4:1) was injected in the renal artery in both groups. In the TAE/CRC group, we aspirated the blood containing the emulsion via the renal vein during arterial infusion. We measured the ethanol concentrations of the systemic circulation. Four days after embolization, the kidneys in both groups were removed and histopathologic examination was performed and results were compared.

Results: The mean systemic ethanol concentration was less than 0.1 mg/mL in the TAE/CRC group and 0.28 mg/mL +/- 0.15 (standard deviation) in the TAE group (P < .002). In both groups, about 90% of the kidney was shown histopathologically to have undergone coagulation necrosis (no significant difference). The frequency of venous thrombus formation was significantly lower (P = .009) in the TAE/CRC group.

Conclusions: TAE/CRC dramatically reduces ethanol leakage to the systemic circulation without a decrease in embolization effect in the normal swine kidney, and it also reduces the likelihood of venous thrombus formation.