A Single-Center Study on the Outcomes of Target Limb Revascularization in Femoropopliteal Lesions Treated With Drug Coated Balloons and Bare Metal Stents

Purpose: Multiple randomized controlled trials have shown that both drug coated balloons (DCBs) and bare metal stents (BMSs) significantly reduce restenosis in femoropopliteal lesions compared with plain balloon angioplasty. However, few studies have directly compared DCB and BMS treatments. Therefore, the goal of our study was to determine if the rate of target lesion revascularization (TLR) differs between DCB and BMS treatment at our center. Materials and methods: We performed a retrospective chart review of femoropopliteal interventions at a single center from 2009 to 2017. The intervention, patient and lesion characteristics, and TLR events were recorded. Exclusion criteria were loss of follow-up, death, bail-out stenting, and amputation within 60 days of treatment. Freedom from TLR was analyzed over a 3 year period with Kaplan-Meier survival curves. Cox hazard ratios were calculated to account for patient and lesion characteristics. Results: A total of 322 lesions (234 patients) treated with DCBs and 225 lesions (194 patients) treated with BMSs were included in this study. There were significant differences in baseline patient and lesion characteristics between groups—a greater proportion of women, patients with dyslipidemia, and lesions with popliteal involvement were treated with DCBs. There was no difference in the freedom from TLR between DCBs and BMSs. Accounting for patient and lesion characteristics, there was still no difference between DCBs and BMSs on the hazard of TLR. While our analysis did not detect a difference in the rate of TLR, there was a significant difference in the type of TLR. Compared with DCBs, a greater proportion of lesions initially treated with BMSs were retreated via surgical bypass rather than endovascular intervention, suggesting that lesions treated with DCBs may be more amenable to future endovascular intervention. Conclusion: Our retrospective analysis showed no difference in the rate of TLR between lesions treated with DCBs and BMSs. However, DCBs were more often used in complicated lesions involving popliteal arteries and may also allow for easier endovascular reintervention.

Automated segmentation of metal stent and bioresorbable vascular scaffold in intravascular optical coherence tomography images using deep learning architectures

Percutaneous Coronary Intervention (PCI) with stent placement is a treatment effective for coronary artery diseases. Intravascular optical coherence tomography (OCT) with high resolution is used clinically to visualize stent deployment and restenosis, facilitating PCI operation and for complication inspection. Automated stent struts segmentation in OCT images is necessary as each pullback of OCT images could contain thousands of stent struts. In this paper, a deep learning framework is proposed and demonstrated for the automated segmentation of two major clinical stent types: metal stents and bioresorbable vascular scaffolds (BVS). U-Net, the current most prominent deep learning network in biomedical segmentation, was implemented for segmentation with cropped input. The architectures of MobileNetV2 and DenseNet121 were also adapted into U-Net for improvement in speed and accuracy. The results suggested that the proposed automated algorithm’s segmentation performance approaches the level of independent human observers and is feasible for both types of stents despite their distinct appearance. U-Net with DenseNet121 encoder (U-Dense) performed best with Dice’s coefficient of 0.86 for BVS segmentation, and precision/recall of 0.92/0.92 for metal stent segmentation under optimal crop window size of 256.

Novel 15-mm-long lumen-apposing metal stent for endoscopic ultrasound-guided drainage of pancreatic fluid collections located ≥10 mm from the luminal wall

Background Endoscopic ultrasound (EUS)-guided drainage of pancreatic fluid collections (PFCs) by cautery-enhanced lumen-apposing metal stents (LAMS) has largely been limited to collections located < 10 mm from the luminal wall. We present outcomes of the use of a novel 15-mm-long cautery-enhanced LAMS for drainage of PFCs located ≥ 10 mm away. Methods This international, multicenter study analyzed all adults with PFCs located ≥ 10 mm from the luminal wall who were treated by EUS-guided drainage using the 15-mm-long cautery-enhanced LAMS. The primary outcome was technical success. Secondary outcomes included clinical success (decrease in PFC size by ≥ 50 % at 30 days and resolution of clinical symptoms without surgical intervention), complications, and recurrence. Results 35 patients (median age 57 years; interquartile range [IQR] 47–64 years; 49 % male) underwent novel LAMS placement for drainage of PFCs (26 walled-off necrosis, 9 pseudocysts), measuring 85 mm (IQR 64–117) maximal diameter and located 11.8 mm (IQR 10–12.3; range 10–14) from the gastric/duodenal wall. Technical and clinical success were high (both 97 %), with recurrence in one patient (3 %) at a median follow-up of 123 days (58–236). Three complications occurred (9 %; one mild, two moderate). Conclusions The 15-mm-long cautery-enhanced LAMS was feasible and safe for drainage of PFCs located 10–14 mm from the luminal wall.

Drug-eluting versus bare metal stents in saphenous vein grafts compared to native coronary vessels. The NORSTENT study.

Background. Drug-eluting stents (DES) reduce target lesion revascularization (TLR) with no effect on mortality or myocardial infarction (MI) compared to bare metal stents (BMS) in native vessels. Randomized stent studies in saphenous vein grafts (SVG) are few and the reported effects are ambiguous. The NORSTENT study is the first to randomize lesions to percutaneous coronary intervention (PCI) in native vessels and SVG. Aims. To compare rate of mortality, MI and TLR across stent and vessel types. Methods. In this substudy 6087 patients with a single lesion in native vessels and 164 in SVG, were followed for 5 years. Results. MI was more frequent in SVG (subdistributional hazard ratio (SHR) 4.95 (3.75 – 6.54, p<0.001), but not affected by stent type. In the first 500 days DES reduced TLR in native vessels (SHR 0.21 ( 0.15 – 0.30)p<0.001) and SVG (SHR 0.18 (0.04 – 0.80) p=0.02). Thereafter DES and BMS were equivalent in native vessels, but DES had a higher TLR rate than BMS in SVG (SHR 3.31 (1.23 – 8.94) p=0.02). After 5 years the TLR rate was still significantly lower for DES in native vessels (3.2 % versus 7.8 %, p<0.001) but not in SVG (21.4 % vs 18. 4%). Conclusion: In SVG no difference in TLR between DES and BMS was observed after 5 years in contrast to persistent benefit in native vessels. The high rate of TLR and myocardial infarction in SVG makes treatment of native vessels a preference whenever feasible and better treatment options for SVG are warranted.

Bare Metal Stents on Resveratrol-Coated Balloons in Porcine Coronary and Peripheral Arteries

Balloon angioplasty and stent implantation are standard techniques to reopen stenotic vessels. Often, balloons or stents coated with cytostatic drugs are used to prevent re-occlusion of the arteries. Resveratrol, which is known for its numerous beneficial effects on cardiovascular health, is used as an antioxidant additive on paclitaxel-coated balloon catheters. What is still unclear is whether resveratrol-only balloon coating in combination with a bare metal stent (BMS) also has positive effects on vascular healing. Here, we analyzed neointimal thickening, fibrin deposition, inflammation, vasa vasorum density, and reendothelialization after implantation of BMS via a resveratrol coated balloon approach in a porcine model. In general, resveratrol treatment did not result in significantly altered responses compared to the control group in peripheral arteries. In coronary arteries, an increase in vasa vasorum density became evident three days after resveratrol treatment compared to the control group and abolished up to day 7. Significant effects of the resveratrol treatment on the fibrin score or intima-media area were transient and restricted to either peripheral or coronary arteries. In conclusion, local single-dose resveratrol treatment via a resveratrol-only coated balloon and BMS approach did not lead to adverse systemic or local effects, but also no significant beneficial effects on vascular healing were detected in the current study.