Efficacy and safety of a magnesium stearate paclitaxel coated balloon catheter in the porcine coronary model

Significantly improved antifouling capability of silicone rubber surfaces by covalently bonded acrylated agarose towards biomedical applications

Bacteria have the extraordinary ability to adhere to biomaterial surfaces and form multicellular structures known as biofilms, which have a detrimental impact on the performance of medical devices. Herein, an investigation highlighted the effective inhibition of bacteria adhesion and overgrowth on silicone rubber surface by grafting polysaccharide, agarose (AG), to construct hydrophilic and negatively charged surfaces. Because of the strong hydration capacity of agarose, the water contact angle of the modified silicone rubber surfaces was significantly reduced from 107.6 ± 2.7° to 19.3 ± 2.6°, which successfully limited bacterial adherence. Most importantly, the durability and stability of coating were observed after 10 days of simulated dynamic microenvironment in vivo, exhibiting a long service life. This modification method did not compromise biocompatibility of silicone rubber, opening a door to new applications for silicone rubber in the field of biomedical materials.

Drug-loaded balloon with built-in NIR controlled tip-separable microneedles for long-effective arteriosclerosis treatment

Drug-eluting balloon (DEB) angioplasty has emerged as an effective treatment for cardiovascular and cerebrovascular diseases. However, distal embolism and late lumen restenosis could be caused by drug loss during DEB handling and rapid drug metabolization. Here, a drug-loaded balloon equipped with tip-separable microneedles on the balloon surface (MNDLB) was developed. Inbuilt near-infrared (NIR) ring laser inside the catheter inner shaft was introduced to activate the biodegradable microneedle tips for the first time. The drug-loaded tips thus could be embedded in the vasculature and then released antiproliferative drug - paclitaxel slowly via polymer degradation for more than half a year. A significant increase in drug delivery efficiency and superior therapeutic effectiveness compared with the standard DEB were demonstrated using an atherosclerosis rabbit model.

Improvement of Outcome for Treatment of ‘Restenosis-prone’ Vascular Lesions? Potential Impact of the Paclitaxel dose on Late Lumen Loss in Porcine Peripheral Arteries

Purpose

Clinical data indicate that the drug density on drug-coated balloons (DCBs) might have a role on treatment effect and durability. The aim of the current study was to investigate inhibition of neointimal formation and potential adverse effects after treatment with a novel double-dose DCB in swine.

Material and methods

A four-week study was performed in peripheral arteries of 12 domestic pigs after vessel injury and stent implantation. The novel double-dose DCB with 6-µg paclitaxel (Ptx)/mm2 balloon surface (1 × 6) was compared to a standard DCB with 3.5 µg Ptx/mm2 (3.5) and uncoated balloons (POBA). Potential adverse effects were stimulated by using three fully overlapping DCBs with 6 µg Ptx/mm2 each (3 × 6). Quantitative angiography, histomorphometry and histopathological analyses were performed.

Results

Higher paclitaxel doses per square millimeter of treated arteries were associated with reduced late lumen loss (LLL) in quantitative angiography 4 weeks after treatment (POBA: 0.91 ± 0.75 mm; 3.5: 0.45 ± 0.53 mm; 1 × 6: 0.21 ± 0.41 mm; 3 × 6: − 0.38 ± 0.65 mm). In histomorphometry, maximal neointimal thickness and neointimal area were the lowest for the 1 × 6 group (0.15 ± 0.06 mm/1.5 ± 0.4 mm2), followed by 3 × 6 (0.20 ± 0.07 mm/1.8 ± 0.4 mm2), 3.5 (0.22 ± 0.12 mm/2.2 ± 1.1 mm2) and POBA (0.30 ± 0.07 mm/3.2 ± 0.7 mm2). Downstream tissue showed histopathological changes in all groups including POBA, in larger number and different quality (e.g., edema, inflammation, vessel wall necrosis, vasculitis and perivasculitis) in the 3 × 6 group, which did not cause clinical or functional abnormalities throughout the study.

Conclusion

Treatment with the double-dose DCB (6 µg Ptx/mm2) tended to increase inhibition of in-stent neointimal formation and to diminish LLL after peripheral intervention in the porcine model compared to a market-approved DCB with 3.5 µg Ptx/mm2.