Percutaneous introducibility of the expandable vascular sheath system and injury potential of balloon-assisted thrombectomy: Preliminary in vivo results

Purpose: To test the percutaneous introducibility of the expandable vascular sheath (EVS) system and the safety of percutaneous balloon-assisted thrombectomy. Methods: The EVS was inserted directly (n = 9) or through 9.5 Fr regular vascular introducer sheath (n = 9) into the femoral arteries and veins and carotid arteries in four dogs (18-21 kg). Balloon-assisted thrombectomies were simulated in iliac arteries. Histologic examinations were done at sites of funnel deployment immediately (n = 4) and 25 days (n = 8) after the intervention. Results: The EVS was successfully introduced into six of nine vessels by a direct percutaneous approach. Balloon-assisted thrombectomy using the EVS device caused localized intimal denudation, disruption of the internal elastic lamina, and mild hemorrhages into the media; one arterial dissection at the site of funnel deployment was seen. All indirect insertions and funnel deployments were successful. Twenty-five days after the experiments, intimal hyperplasia was noted in all cases. Conclusion: Percutaneous mbectomy may cause mild vascular injuries. Direct percutaneous introduction of the EVS device cannot be recommended yet.