Plaque excision in the management of lower-limb ischemia of atherosclerosis and in-stent restenosis with the SilverHawk atherectomy catheter

AIM

Aim of the present study was to compare the effectiveness of plaque excision in management of lower limb ischemia of atherosclerosis and in-stent restenosis with the SilverHawk atherectomy catheter.

METHODS

From November 2010, to August 2011, 43 patients were involved and completed follow-up. They were divided into two groups: group A is the atherosclerotic plaque group (16 cases, 37.2%) and group B is the in-stent restenosis/occlusion lesion group (27 cases, 62.8%). The average age of group A was 68.3 years and group B was 72 years, the mean duration was 27.4 months and 26 months, respectively. Intermittent claudication was 8 cases and 16 cases respectively, and rest pain both was 4 cases, foot ulcer was 1 case and 4 cases, toe gangrene both was 3 cases. Ankle Brachial Index (ABI)≤0.4 was 2 in group A and 8 in group B, ABI>0.4 was 12 and 16, ABI=0 was 2 and 3, respectively. Excision with protective devices in 6 cases. Nine cases and 17 cases received treatment for proximal and distal lesions over the same period, respectively, included the proximal iliac artery stenting 1 case in group A and 5 cases in group B, distal calf arteries stenting 6 cases in group A and 11 cases in group B, balloon angioplasty 2 in group A and 1 in group B. Endpoints included postoperative mortality or amputation of target limb.

RESULTS

Forty-one operations were successful, the technical success rate was 95.3%, one case in group B suffered above-knee amputation. The target vessels of 41 patients maintain patency after discharge. Postoperative claudication distance increased to 500 meters except for one case in each group, all 4 rest pain patients got alleviated, reduced toe ulcer area happened in 1 and 2 cases respectively, all 3 cases of gangrene dried up/infection controlled in each group. Postoperative ABI result 0.7-0.8: 4 in group A and 5 in group B; 0.81-0.9 was 5 and 8; >0.91 was 6 and 13, respectively. Symptom improvement result had no significant difference between the two groups (P>0.05). Follow-up covered 41 patients, average 17.5±3.3 months. Group A patients stayed in good condition, 7 claudication patients's walking distance above 500 meters remains; rest pain no recurrence, one ulcer healing, 2 of 3 toe gangrene self-shedding and stump healing, 1 toe gangrene removed by surgery and wound healing. Group B, 4 of 15 claudication cases recurrence, and received plaque excision again. Rest pain no recurrence. 3 of 4 ulcer healing, 1 ulcer area reduced significantly. One out of 3 gangrene received below knee amputation (toe osteomyelitis), wound healing. One recurrence, angiography showed in-stent severe restenosis, received plaque excision again. One toe gangrene removed by surgery and wound healing.

CONCLUSION

Plaque excision with "SilverHawk" treatment for lower limb ischemia of atherosclerosis or in-stent restenosis is safe and effective. No significant difference for these two lesions in efficacy. Long term follow-up and larger randomized study is needed for further information on treatment.

Response of gerbera jamesonii acrocarpous callus stimulated by mechanical vibration

Applying different mechanical vibrations, 2-3 Hz frequency, to stimulate the gerbera jamesonii acrocarpous callus, we found that it increases the growth rate and the content of soluble protein but decreases the fluidity of cell membranes. When the frequency was greater than 4 Hz, the effect was contrary to that of 2-3 Hz. In this paper, we also prove the double effects in the plant callus growth and explore the mechanism of the double effects in physical stimulation.