Covered Cheatham-Platinum Stent for Treatment of Descending Thoracic Aortic Stenosis Caused by Takayasu Arteritis in Two Children.

Takayasu arteritis (TA) is a chronic type of systemic large vessel vasculitis, mainly involving the aorta and its main branches. Both surgical and endovascular revascularization are effective methods for treating TA-related stenosis of the aorta and its branches. By December 2020, there have been very limited reports on the use of coated Cheatham-Platinum (CP) stents in the treatment of TA associated descending thoracic aortic stenosis. Two children with thoracic aortic stenosis caused by TA who received the covered CP stent in Xuanwu Hospital of Capital Medical University were reported. The follow-up time was 1.5 years and 4 years, respectively. The covered cheatham-platinum (CP) stent may be an alternative treatment for TA associated children with descending aortic stenosis.

Directional atherectomy and drug-coated balloon angioplasty vs. bare nitinol stent angioplasty for femoropopliteal artery lesions.

Background: The present study evaluated the prognosis of directional atherectomy (DA)+drug-coated balloon (DCB) angioplasty for femoropopliteal artery lesions compared with bare nitinol stent (BNS). Patients and methods: This retrospective cohort study included patients with femoropopliteal artery lesions who underwent percutaneous endovascular surgery between January 2016 and June 2019. The primary outcome was the primary patency rate after 12, 24, and 36 months; the secondary outcomes comprised incidence of flow-limiting dissections, technical success, limb salvage, and all-cause death. Results: During the study period, 110 (44%) patients underwent DA+DCB, and 140 (56%) patients underwent bare nitinol stent (BNS). There were no differences in the 12- and 24-month patency rates of the two groups (98.2% vs. 93.6% and 68.2% vs. 60.0%, both p>.05). The 36-month primary patency rate in the DA+DCB group was significantly higher than that of the BNS group (27.3% vs. 15.7%, p=.003). The technical success rate and all-cause death were similar between groups (p>.05). Flow-limiting dissections occurred more frequently in the BNS group than in the DA+DCB group (27.9% vs. 10.9%, p=.033). After adjustment for potential confounders, such as sex, smoking, hypertension, hyperlipidemia, ABI after surgery, TASC II B, lesion length ≥15 cm, two-vessel runoff, and three-vessel runoff, the HR for primary patency rate comparing BNS to DA+DCB was 2.61 (95%CI: 1.61-4.25). Conclusions: In this retrospective cohort study, DA+DCB was associated with a higher 30-month primary patency rate and a lower flow-limiting dissection incidence than BNS.

Midterm Outcome of Directional Atherectomy Combined with Drug-Coated Balloon Angioplasty Versus Drug-Coated Balloon Angioplasty Alone for Femoropopliteal Arteriosclerosis Obliterans.

BACKGROUND: The "leave nothing behind" strategies have been becoming a popular treatment for femoropopliteal arteriosclerosis obliterans. Atherectomy before drug-coated balloon (DCB) angioplasty may have an advantage in improving the efficiency of drug delivery into the blood vessel wall. This study aimed to compare the therapeutic effects of directional atherectomy combined with DCB angioplasty with DCB angioplasty alone in the treatment of femoropopliteal arteriosclerosis obliterans. METHODS: Patients with femoropopliteal arteriosclerosis obliterans who received endovascular therapy from June 2016 to June 2018 in our hospital and presented with life-limiting claudication or severe chronic limb ischemia comprised the study cohort. The patients were randomized to receive directional atherectomy combined with DCB angioplasty (n = 45) or DCB alone (n = 49). Ninety-four patients were enrolled in our study with 72 males, and the mean age was 67 ± 10 years. The mean lesion length was 112 ± 64 mm. RESULTS: There were no significant differences in the baseline characteristics of patients and lesions between the 2 randomized groups (P > 0.05). Flow-limiting dissections occurred more frequently in the DCB group (n = 12; 24.5%) than in the DA-DCB group (n = 2; 4.4%; P = 0.006). The technical success rate in the DA-DCB group was superior to that in the DCB group (95.6% vs. 75.5%, P = 0.006). The mean follow-up duration was 16.7 ± 6.1 months in the DCB group and 15.3 ± 5.8 months in the DA-DCB group. No amputations were performed. The overall mortality in the DCB group was 4.1% (2/49), while all patients survived in the DA-DCB group. The 12-month and 24-month primary patencies in the DA-DCB group were greater than those in the DCB group (80.5% vs. 75.7% and 67.1% vs. 55.1%, respectively); however, using all available patency data, no significant differences over time were observed (P = 0.377). CONCLUSIONS: In this study, directional atherectomy combined with DCB angioplasty can decrease the flow-limiting dissection rate in the treatment of femoropopliteal arteriosclerosis obliterans compared with DCB angioplasty alone. There was no significant difference between the 2 groups in terms of primary patency rate which was needed to be further clarified.

Biocompatibility evaluation of heparin-conjugated poly(ε-caprolactone) scaffolds in a rat subcutaneous implantation model.

Vascular grafts prepared from synthetic polymers have serious shortcomings that can be resolved by surface modification, such as by immobilizing heparin. In this study, the mechanical properties, biocompatibility, anticoagulation property, and water contact angle of two heparin-conjugated poly(ε-caprolactone) scaffolds (PCL-hexamethylendiamine-heparin, PCL-HMD-H. PCL-lysine-heparin, PCL-LYS-H) were compared to identify a preferred heparin conjugation method. An evaluation of the subcutaneous tissue biocompatibility of the scaffolds demonstrated that PCL-HMD-H had better endothelial cell proliferation than the PCL-LYS-H and was therefore a promising scaffold candidate for use in vascular tissue-engineering.

Vascular Remodeling Process of Heparin-Conjugated Poly(ε-Caprolactone) Scaffold in a Rat Abdominal Aorta Replacement Model.

In the field of vascular graft research, poly-ε-caprolactone (PCL) is used owing to its good mechanical strength and biocompatibility. In this study, PCL scaffold was prepared by electrospinning and surface modification with heparin via hexamethylenediamine. Then the scaffolds were implanted into the infrarenal abdominal aorta of Wistar rats and contrast-enhanced micro-ultrasound was used to monitor the patency of grafts after implantation. These grafts were extracted from the rats at 1, 3, and 6 months for histological analysis, immunofluorescence staining, and scanning electron microscopy observation. Although some grafts experienced aneurysmal change, results showed that all implanted grafts were patent during the course of 6 months and these grafts demonstrated well-organized neotissue with endothelium formation, smooth muscle regeneration, and extracellular matrix formation. Such findings confirm feasibility to create heparin-conjugated scaffolds of next-generation vascular grafts.

In vivo evaluation of safety and performance of a tapered nitinol venous stent with inclined proximal end in an ovine iliac venous model.

A tapered stent with inclined proximal end is designed for fitting the iliac anatomically. The aim of the present study was to evaluate the safety and performance of the new stent in ovine left iliac veins. The experiment was performed in 30 adult sheep, and one nitinol-based VENA-BT® iliac venous stent (KYD stent) was implanted into each animal's left common iliac vein. Follow-up in all sheep consisted of angiographic, macroscopic, and microscopic examinations at Day 0 (< 24 h), Day 30, Day 90, Day 180 and Day 360 post-stenting (six animals per each time-point). 30 healthy ~ 50 kg sheep were included in this study and randomly divided into five groups according to the follow-up timepoint. All stents were implanted successfully into the left ovine common iliac vein. No significant migration occurred at follow-up. There is no statistically significant difference between the groups (p > 0.05), indicating no serious lumen loss occurred during the follow-up period. Common iliac venous pressure was further measured and the results further indicated the lumen patency at follow-up. Histological examinations indicated that no vessel injury and wall rupture, stent damage, and luminal thrombus occurred. There was moderate inflammatory cell infiltration around the stent in Day-0 and Day-30 groups with the average inflammation score of 2.278 and 2.167, respectively. The inflammatory reaction was significantly reduced in Day-90, Day-180 and Day-360 groups and the average inflammation scores were 0.9444 (p < 0.001, Day-90 vs Day-0), 1.167 (p < 0.001, Day-180 vs Day-0) and 0.667 (p < 0.001, Day-90 vs Day-0), respectively. The microscopic examinations found that the stents were well covered by endothelial cells in all follow-up time points. The results suggested that the KYD stent is feasible and safe in animal model. Future clinical studies may be required to further evaluate its safety and efficacy.

Poly(ethylene glycol) Hydrogels with the Sustained Release of Hepatocyte Growth Factor for Enhancing Vascular Regeneration.

The surface modification of biologically active factors on tissue-engineering vascular scaffold fails to fulfill the mechanical property and bioactive compounds' sustained release in vivo and results in the inhibition of tissue regeneration of small-diameter vascular grafts in vascular replacement therapies. In this study, biodegradable poly(ε-caprolactone) (PCL) was applied for scaffold preparation, and poly(ethylene glycol) (PG) hydrogel was used to load heparin and hepatocyte growth factor (HGF). In vitro analysis demonstrated that the PCL scaffold could inhibit the heparin release from the PG hydrogel, and the PG hydrogel could inhibit heparin release during the process of PCL degradation. Finally, it results in sustained release of HGF and heparin from the PCL-PG-HGF scaffold. The mechanical property of this hybrid scaffold improved after being coated with the PG hydrogel. In addition, the PCL-PG-HGF scaffold illustrated no inflammatory lesions, organ damage, or biological toxicity in all primary organs, with rapid organization of the endothelial cell layer, smooth muscle regeneration, and extracellular matrix formation. These results indicated that the PCL-PG-HGF scaffold is biocompatible and provides a microenvironment in which a tissue-engineered vascular graft with anticoagulant properties allows regeneration of vascular tissue (Scheme 1). Such findings confirm the feasibility of creating hydrogel scaffolds coated with bioactive factors to prepare novel vascular grafts.

A Retrospective Comparative Study of Twelve-Month Clinical Outcomes for Drug-Coating Balloon Angioplasty and Stent Implantation in Treating Patients with Popliteal Obstructive Lesions.

PURPOSE: Despite increased interest in treating superficial femoral and popliteal arteries with endovascular technology, there is little data regarding comparative results of different treatment modalities in the popliteal artery. It was hypothesized that to improve clinical outcomes in this segment, drug-coating balloon (DCB) angioplasty would not be inferior to stent implantation. METHODS: The records of consecutive Chinese patients with popliteal lesions who were treated with DCB or stenting between June 2016 and February 2017 were retrospectively reviewed. The preoperative demographic, lesion characteristics and postoperative outcomes were compared and statistically analyzed. All patients were divided into different subgroups according to the degree of calcium or degree of ischemia. RESULTS: One hundred two consecutive patients with popliteal lesions were treated with DCB or stenting and 95 (93.1%) completed a follow-up. Critical limb ischemia was present in 70.5% and occlusions were present in 61.1% of patients. DCB angioplasty was performed on 43 patients and angioplasty with primary stenting was performed on 52 patients. There was no difference in twelve-month primary patency (79.1% vs 82.7%; P = 0.687), secondary patency (95.3% vs 94.2%; P = 0.808) and amputation-free survival (93.0% vs 94.2%; P = 0.825) between the DCB group and stent groups. In patients with severe calcium, the twelve-month primary patency (61.1% vs. 79.2%; P = 0.239) and amputation-free survival (83.3% vs 87.5%; P = 0.739) did not differ between the DCB and stent groups. CONCLUSIONS: This study demonstrates that DCB treatment in Chinese patients with popliteal atherosclerotic occlusive lesions can be associated with similar twelve-month patency and amputation-free survival compared to stenting, even in patients with severe calcification. LEVEL OF EVIDENCE: Level 3a, Non-randomized follow-up study.

Drug-Coated Balloon Angioplasty and Debulking for the Treatment of Femoropopliteal In-Stent Restenosis: A Systematic Review and Meta-Analysis.

The purpose of this article was to compare the efficiency and safety of drug-coated balloon angioplasty (DCB) and atherectomy with percutaneous transluminal angioplasty (PTA) in patients with femoropopliteal in-stent restenosis (ISR). Pubmed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) (all up to March 2019) were searched systematically. Trial sequential analysis (TSA) was conducted. 5 studies with 599 participants were included. Compared with PTA, DCB significantly increased the rate of patency (6 months: RR 1.65, 95% CI 1.30 to 2.09, P < 0.01; 12 months: RR 2.38, 95% CI 1.71 to 3.30, P < 0.01) and the rate freedom from target lesion revascularization (TLR) (6 months: RR 1.18, 95% CI 1.09 to 1.28, P < 0.01; 12 months: RR 1.56, 95% CI 1.33 to 1.82, P < 0.01) at 6 and 12 months follow-up, and the TSA results showed these outcomes were reliable. The rate of clinical improvement by ≥1 Rutherford category in the DCB group was higher than that in the PTA group (6 months: RR 1.35, 95% CI 1.03 to 1.75, P = 0.03; 12 months: RR 1.46, 95% CI 1.17 to 1.82, P < 0.01) at 6 and 12 months. There is no statistically difference of ABI, all-cause mortality, and incidence of amputation between DCB group and PTA group (MD 0.03, 95% CI -0.03 to 0.08, P = 0.40; RR 1.24, 95% CI 0.46 to 3.34, P = 0.67; RR 0.32, 95% CI 0.01 to 7.61, P = 0.48). Compared with PTA, the rate of patency and freedom from TLR in the laser atherectomy (LD) group was higher than that in the PTA group (patency: 6 months: RR 1.28, 95% CI 1.01 to 1.64, P < 0.05, 12 months: RR 2.25, 95% CI 1.14 to 4.44, P < 0.05; freedom from TLR: 6 months: RR 1.27, 95% CI 1.05 to 1.53, P = 0.01, 12 months: RR 1.59, 95% CI 1.12 to 2.25, P = 0.01) at 6 and 12 months follow-up. In conclusion, DCB and LD had superior clinical (freedom from TLR and clinical improvement) and angiographic outcomes (patency rate) compared with PTA for the treatment of femoropopliteal ISR. Moreover, DCB and LD had a low incidence of amputation and mortality and were relatively safe methods.