Rotating basket for mechanical lysis of venous thrombus/dialysis fistulae. 5F bare or 7 F devices over an 0.18 wire.
The Arrow-Trerotola percutaneous thrombolytic device (Arrow International, Reading, Pa) consists of a motor-driven fragmentation cage made of nitinol that is attached to a drive cable. The cage and drive cable are housed in the catheter that constrains the self-expanding cage in the closed position. In the open position, the cage expands to diameter 9 mm. There is a soft, rubber tip at the end of the device. The open cage is rotated in the graft at a fixed speed (3,000 rpm) with a separate handheld rotator unit. In bench-top experiments, the device breaks up clot into particles less than 3 mm in diameter, with the majority < 1 mm .
The device is advanced past the clot in the closed position, and the cage is deployed by retracting the 5-F catheter. The rotator unit is activated to spin the cage, which is then pulled slowly through the clot, macerating as well as stripping clot from the graft walls. The resultant slurry can be aspirated through the 5-F sheath. According to the in vitro data, two passes of the device yield optimal clot fragmentation.
For clearing haemodialysis fistula . Two short 7 f sheaths are placed approximately 10cm apart facing antegradely and retrogradely to clear the arterial and venous end of the fistula. 5000units of heparin are instilled into the fistula through the sheath or it is possible to inject through the device side arm. This is also useful to inject contrast during the procedure. The venous outflow is usually cleared first.
Reported technical success is in the region of 95% and 3 month primary patency of 39% and compares well with other devices and pulse spray (1-2).
I have used this device for thrombosed grafts, iliac veins and pulmonary arteries for PE. It is very quick and effective.
You need to be careful to withdraw the device and not advance during the thrombectomy. I have used it in a stent (although contraindicated) and taken out a piece of the stent , so avoid. Limited by the size to vessels >6mm and again I have avulsed a cephalic vein which was immature (no major sequelae).
My rating 3-4/5 overall.
No conflict declared.
Dr Raman Uberoi
Consultant Interventional Radiologist
Oxford, England
1. Trerotola S O, Vesely TM, Lund, GB et al (1998) Treatment of Thrombosed Hemodialysis Access Grafts: Arrow-Trerotola Percutaneous Thrombolytic device Versus pulse spray Thrombolysis.Radiology :206: 403-414.
2. Vesely TM (2003). Mechanical Thrombectomy Devices to treat Thrombosed Hemodialysis Grafts.Techniques in Vascular and Interventional Radiology: 6 (1): 35-41.
