Tibiopedal and distal femoral retrograde vascular access for challenging chronic total occlusions: predictors for technical success, and complication rates in a large single-center cohort.

OBJECTIVE: To evaluate the safety and effectiveness of tibiopedal and distal femoral access for retrograde crossing of chronic total occlusion (CTO) in Rutherford stage III to VI peripheral arterial occlusive disease, and to determine factors that correlate with technical success. MATERIAL AND METHODS: One hundred seventy-one consecutive patients were included in this retrospective study. Rutherford stages were III, IV, and V/VI in 24%, 8%, and 67% of patients. Inclusion criteria were CTO at the superficial femoral (SFA), popliteal (PA), and/or below-the-knee (BTK) level, and a failed antegrade treatment followed by a distal retrograde approach. The numbers of occluded vascular levels (OVL), lesion length, degree of calcification, technical success rate, complications, and clinical outcome were noted. RESULTS: OVL were 1 in 72%, 2 in 20%, and 3 in 8% of patients. CTOs were longer than 20 cm in 45.6% of cases and showed severe calcifications in 50.3%. Target vessels for distal access were the distal SFA/PA in 17% and BTK in 83%. The overall technical success rate was 82%. Severe calcification decreased technical success (p = 0.01) despite lesion length and Rutherford stage. Clinical outcome improved in 123/152 patients with a significant increase of the median ABI (N = 158) from 0.53 (interquartile range 0.39 to 0.61) to 0.85 (0.59 to 1.03; p < 0.001). Complications were reported in 7.6% cases with 2.3% related to the distal vascular access. CONCLUSION: The tibiopedal and distal femoral retrograde access presents a safe and effective treatment option of CTOs at the thigh and/or BTK after a failed antegrade attempt improving clinical outcome. Technical success decreased with lesion's degree of calcification. KEY POINTS: • Safety and effectiveness of the tibiopedal and distal femoral access for retrograde crossing of chronic total occlusion. • Target lesion's degree of calcification decreases technical success. • Complications related to the distal vascular access were rare.

Whole body vibration during fracture healing intensifies the effects of estradiol and raloxifene in estrogen-deficient rats.

Current osteoporosis therapies aim to delay bone destruction and have additional anabolic effects. While they have demonstrated some positive effects on bone healing, more progress is needed in this area. This study used the well-known osteoporotic agents estrogen (E) and raloxifene (R) in conjunction with biomechanical whole body vibration (WBV) at a frequency of 70 Hz twice daily for six weeks to stimulate bone healing. Eighty-four 3-month old female Sprague-Dawley rats (12 per group) were bilaterally ovariectomized to develop osteopenia within eight weeks. Osteotomy of the metaphyseal tibiae was performed and fracture healing was then studied using mechanical tests, histomorphometry, computed tomography (µCT), and gene analysis. We found that E and R improved the structure of osteopenic bones as did WBV alone, although significant levels for WBV were seldom reached. Combination treatments significantly enhanced stiffness (R+WBV; p<0.05), endosteal bone (R+WBV; p<0.01), and trabecular density (E+WBV; p<0.05, R+WBV; p<0.05). In addition, the expression of osteoclast-specific Trap was significantly reduced after treatment with E, R, or their combination with WBV (p<0.01). The effects were additive and not inhibitory, leading us to conclude that the combined applications of WBV with E or R may improve the healing of osteopenic bones. The therapies studied are all currently approved for human use, suggesting ready applicability to clinical practice. To better understand the effects of WBV on osteopenic bones, the ideal vibration regime will require further study.