Recanalization of thrombosed superficial femoral arteries with a hydraulic thrombectomy catheter in a canine model

Early experience with a rotational thrombectomy device for treatment of acute and subacute infra-aortic arterial occlusions

PURPOSE

To evaluate a rotational thrombectomy device in the treatment of acute and subacute/chronic thrombotic infra-aortic occlusions of native vessels and bypass grafts.

METHODS

From July 2000 to February 2002, 98 patients (65 men; mean age 66+/-9 years, range 47-90) with 100 thrombotic occlusions (mean age of occlusion 31+/-33 days, range 0-140) measuring an average of 21+/-11 cm long (range 2-40) were treated with rotational thrombectomy (Rotarex). There were 33 acute (</=14 days) thrombotic/embolic native artery occlusions (group I), 58 subacute/chronic (>14 days) native artery occlusions (group II), and 9 acute bypass graft occlusions (group III).

RESULTS

The device activation time was 4.9+/-1.4 minutes, during which 4.0+/-1.4 passes of the device were performed. The amount of aspirated fluid was 240+/-119 mL. Slightly less than half the arteries (48%) were stented. Primary success (residual stenosis <30%) was achieved in 92% (94% for group I, 93% for group II, and 78% for group III; 100% for the ipsilateral approach, 56% for the crossover approach). Among the 18 complications, 3 were serious (2 amputations after unsuccessful intervention and 1 death); there were 8 vessel perforations and 7 cases of peripheral embolization. Thirty-day survival and limb salvage was 88% for group I, 100% for group II, and 66% for group III.

CONCLUSIONS

The device is an easy-to-handle, useful tool for ipsilateral treatment of acute and subacute thrombotic arterial and bypass graft occlusions. The use of this device is limited by the 8-F diameter of the catheter and the limited capacity for crossover interventions.

Comparison of a new recirculation thrombectomy catheter with other devices of the same type: in vitro and in vivo evaluations

RATIONALE AND OBJECTIVES

To compare a new 7 Fr. Helix thrombectomy catheter with Amplatz thrombectomy devices (ATD) with respect to clot fragmentation efficiency, hemolytic potential, and risk for vascular trauma.

MATERIALS AND METHODS

Particle size was evaluated following the maceration of 8-to-10-day-old clots, each weighing 6 +/- 0.01 g. The clots were macerated using devices of various sizes, including the 7-Fr. Helix thrombectomy catheter, the 7-Fr. over-the-wire (OTW), 8-Fr. ATD and the 6-Fr. ATD. The number of particles by weight was quantified. The 7-Fr. Helix and the 8-Fr. ATD were tested in the native iliac vein of six dogs without presence of clots. Blood samples were obtained before, during, and at 1, 3, 6, 24, and 48 hours after the procedure, to monitor the hemolytic effects. The treated iliac veins were examined histologically.

RESULTS

Most of the clot was fragmented into particles <10 microm. The mean percentage by weight of the original clot that remained as particles larger than 10 microm was 1.59% in the 7-Fr. Helix group. This was significantly less than 3.10% with the 6-Fr. ATD, 2.57% with 7-Fr. OTW and 2.44% in the 8-Fr. ATD group (<0.01). In vivo results showed a higher plasma free hemoglobin (PFH) level starting 5 minutes after initiating the ATD activation, reaching its peak after completion of the activation, and declining afterward, with return to the baseline at 24 hours. The haptoglobin level tended to decline slightly at 10 minutes, reaching its lowest level at 24 hours, and starting to recover at 48 hours. A similar pattern of PFH and haptoglobin changes was found in both groups. There were no significant differences regarding hemolytic effect of the two tested devices. No significant changes of creatinine were observed for up to 48 hours after procedures. Focal microthrombosis was seen in two sites of two vessels treated with the 7-Fr. Helix and a focal injury of a venous valve was noted in the 8-Fr. ATD group. The media and internal elastic lamina (IEL) were intact in all cases.

CONCLUSION

The newly designed 7-Fr. Helix is more effective in fragmentation in vitro clots than the 6 Fr. ATD, 7-Fr. OTW and the 8-Fr. ATD. The 7-Fr. Helix and the 8-Fr. ATD produced hemolytic effects, but they appeared to be tolerated by the animals. The in vivo results indicated that the 7-Fr. Helix appears to be as safe as the 8-Fr. ATD.

The use of mechanical thrombectomy devices in the management of acute peripheral arterial occlusive disease

A number of percutaneous mechanical thrombectomy devices are currently being used or undergoing clinical evaluation for the treatment of acute and chronic limb-threatening ischemia. Preliminary studies on the safety, efficacy, and device limitations have spurred an interest in percutaneous techniques for thrombus debulking as stand-alone therapy or an adjunct to pharmacologic thrombolysis. The devices have various mechanisms or combinations of mechanisms to optimize thrombus removal. Efficacy of thrombus removal is balanced by the propensity for vessel wall damage and distal embolization, especially for wall-contact devices (Arrow-Trerotola device and Cragg and Castañeda brushes). Initial experience in hemodialysis graft occlusion has subsequently moved on to peripheral arterial occlusions. Although the U.S. Food and Drug Administration has approved eight mechanical thrombectomy devices (MTDs) for use in thrombosed hemodialysis grafts, only the AngioJet LF140 is currently approved for use in peripheral arterial occlusive disease. Nevertheless, numerous clinical articles and abstracts have reported the "off-label" use of MTDs in the management of limb-threatening ischemia. A description of the eight MTDs and a review of the current literature on use of MTDs for acute peripheral arterial occlusive disease are provided.