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Purpose: Endovascular therapies (EVTs) for symptomatic lower extremity peripheral artery disease (PAD) are efficient and minimally invasive. However, patients with PAD tend to have high bleeding risk (HBR), and there are limited data regarding the HBR for patients with PAD after EVT. In this study, we investigated the prevalence and severity of HBR, as well as its association with clinical outcomes in the patients with PAD who underwent EVT. Materials and Methods: The Academic Research Consortium for High Bleeding Risk (ARC-HBR) criteria were applied to 732 consecutive patients with lower extremity PAD post-EVT to assess the prevalence of HBR, and its association with major bleeding events, all-cause mortality, and ischemic events. The ARC-HBR scores (1 point for each major criterion and 0.5 points for each minor criterion) were obtained and the patients were divided into four groups (score: 0–0.5; low risk, score: 1–1.5; moderate risk, score: 2–2.5; high risk, and score: ≥3; very high risk) according to the score. Major bleeding events were defined as Bleeding Academic Research Consortium type-3 or type-5 bleeding, and ischemic events were defined as the composite of myocardial infarction, ischemic stroke, and acute limb ischemia within 2 years. Results: High bleeding risk occurred in 78.8% of the patients. Major bleeding events, all-cause mortality, and ischemic events occurred in 9.7%, 18.7%, and 6.4% of the study cohort, respectively, within 2 years. During the follow-up period, major bleeding events significantly increased with the ARC-HBR score. The severity of the ARC-HBR score was significantly associated with an increased risk of major bleeding events (high risk: adjusted hazard ratio [HR] 5.62; 95% confidence interval [CI]: [1.28, 24.62]; p=0.022; very high risk: adjusted HR: 10.37; 95% CI: [2.32, 46.30]; p=0.002). All-cause mortality and ischemic events also significantly increased with higher ARC-HBR score. Conclusions: High bleeding risk patients with lower extremity PAD can be at a high risk of bleeding events, mortality, and ischemic events after EVT. The ARC-HBR criteria and its associated scores can successfully stratify HBR patients and assess the bleeding risk in patients with lower extremity PAD who undergo EVT. Clinical Impact Endovascular therapies (EVTs) for symptomatic lower extremity peripheral artery disease (PAD) are efficient and minimally invasive. However, patients with PAD tend to have high bleeding risk (HBR), and there are limited data regarding the HBR for patients with PAD after EVT. Post EVT, most of the patients with PAD were classified as having HBR using the Academic Research Consortium for HBR (ARC-HBR) criteria and the rate of bleeding events as well as mortality and ischemic events within 2 years increased as the ARC-HBR score increased in this retrospective study of 732 participants. HBR patients with PAD can be at high risk of not only bleeding events but also mortality and ischemic events in the mid-term. The ARC-HBR criteria and its associated scores can successfully stratify HBR patients and assess the bleeding risk in patients with PAD who underwent EVT.

An ~10-y-old male sheep had anorexia and progressive weight loss for ~1 mo. The sheep was emaciated, and 20 d later, became recumbent and lethargic, and was hypoglycemic (0.33 mmol/L; RI: 2.6–4.4 mmol/L). The sheep was euthanized because of poor prognosis, and submitted for autopsy. We found no gross lesions in the pancreas; however, histologically, focal proliferations of round-to-polygonal cells were separated by connective tissue into small nests. These proliferating cells, which had abundant eosinophilic-to-amphophilic cytoplasm and hyperchromatic nuclei, were immunopositive for insulin and negative for glucagon and somatostatin; the lesion was diagnosed as an insulinoma. Insulinoma has not been reported previously in sheep, to our knowledge. In addition, autopsy and histologic examination revealed the presence of an adrenocortical carcinoma with myxoid differentiation and a thyroid C-cell carcinoma. Our case indicates that multiple endocrine neoplasms can occur in sheep, as in other animal species.

Vascular closure devices (VCDs) are widely used to achieve rapid hemostasis after percutaneous intervention via the common femoral artery (CFA), with well-established efficacy and safety. Although VCD-related artery occlusion is rare, it can be critical. A 72-year-old female underwent endovascular therapy (EVT) for stent occlusion in the left superficial femoral artery through a 7-Fr guiding sheath from the right CFA. After the procedure, an acute right popliteal artery (POP-A) occlusion, associated with the EXOSEAL VCD plug, occurred. The plug material was successfully removed using a bidirectional approach. The migration plug was blocked to prevent distal vessel migration and pushed gently to close the antegrade system, using an over-the-wire balloon from the retrograde site. We named this the “Push balloon INto vessel and Close Embolus from Retrograde site” (PINCER) technique. Finally, the plug was successfully removed using biopsy forceps. Acute limb ischemia (ALI) caused by EXOSEAL is a rare condition. Removal of the emboli by EVT is clinically significant because it is minimally invasive. However, it is sometimes difficult to remove the embolus using only antegrade approach; thus, the bidirectional approach using the PINCER technique can be effective in these situations.

In recent years, various devices have been approved for peripheral artery disease with femoropopliteal lesions. However, treatment of long, calcified, and diffused lesions is still challenging because these lesions are associated with restenosis. This report described the case of an 82-year-old man with bilateral severely calcified and diffused long lesions in the superficial femoral artery that was treated using polymer-coated paclitaxel-eluting stent and interwoven nitinol stent. After 6 months, in-stent restenosis was observed at the implantation site of the interwoven nitinol stents. Polymer-coated paclitaxel-eluting stents were deployed at the in-stent restenosis site. After another 6 months, angiography and intravascular ultrasound imaging revealed no restenosis at the polymer-coated paclitaxel-eluting stent site. Optical coherence tomography was also performed, revealing that the stent struts were well covered by neointima, which was very thin at approximately 0.1 mm. This representative case demonstrated substantial differences in the effects of devices; in other words, the superiority of polymer-coated paclitaxel-eluting stent in treating long, diffuse, and calcified lesions indicated that its implantation is a reasonable option when the initial gain was obtained following sufficient vessel preparation.

While treating vascular aneurysms with endovascular technique, short neck and severe bending of the artery are one of the biggest challenges, whether choosing coil embolization or stent-graft (SG) deployment. Here, we report a case with large aneurysm of the splenic artery, which had anomalistically arisen from the superior mesenteric artery and had very severe bending. Because the proximal neck was too short to exclude with SG only, we decided to treat with a combination of coil embolization and SG. At the time of deploying the VIABAHN (self-expandable SG) at the ostium of the splenic artery, the VIABAHN started to deform as the strings were pulled and finally jumped away from the start position. A second VIABAHN was deployed using the sheath-covering technique, which involved alternating short deployment of the VIABAHN with short pullback of the sheath. This report highlights the tricks and traps of deploying VIABAHN at the arteries with very severe bending.

Arterio-ureteral fistulas are relatively rare, but a potentially life-threatening condition because of the possible massive bleeding. An 82-year-old woman with a history of hysterectomy and irradiation for uterine cancer was treated with ureteric stents for recurrent bilateral ureteral stenosis. During the adjustments of the stent, removing the right ureteric stent immediately resulted in massive hematuria. Computed tomography showed that the right ureter coursed above and seemed to be connected to the right external iliac artery. From the clinical history and computed tomography findings, an arterio-ureteral fistula between the right external iliac artery and right ureter was strongly suspected. The GORE® VIABAHN® VBX Stent Graft was deployed from the common iliac artery to the external iliac artery via a 7-French femoral system, followed by post-dilatation. The patient did not develop any complications or recurrence of hematuria after the procedure during the 11-month follow-up. The VBX is a useful device, with a low- profile device and a size-adjustable balloon-expandable stent that depended on the individual vessel size for post-dilatation. However, there are several concerns, such as risk of infection, stent thrombosis/stenosis, and chronic outcome while using stent grafts for treatment. Patients with arterio-ureteral fistulas who were treated using stent grafts should be carefully followed up.

This paper presents a methodology for applying μ-synthesis to a real high-order system: launch vehicle attitude and vibration control. The design involves robust characteristics against uncertainties of the system parameters as well as precise tracking performance under limited rigidity. As the plant dynamics has an extremely high order and unstable character, the standard μ-synthesis cannot be directly applied. Thus, the standard procedure is modified in a specialway in order tomake the approach more efficient. The methodology provided in the study will contribute to a better understanding of how to apply the robust control theory to complicated real problems.