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BackgroundPeripheral arterial disease (PAD) is more common in patients receiving maintenance hemodialysis than in the general population. Critical limb ischemia (CLI), the most severe form of PAD, is associated with high amputation and mortality risk. However, few prospective studies are available evaluating this disease's presentation, risk factors and outcomes for patients receiving hemodialysis.MethodsThe Hsinchu VA study, a prospective multicentre study, investigated the impact of clinical factors on cardiovascular outcomes of patients receiving maintenance hemodialysis from January 2008 until December 2021. We evaluated the presentations and outcomes of patients with newly diagnosed PAD and the correlations of clinical variables with newly diagnosed CLI.ResultsOf 1136 study participants, 1038 had no PAD on enrolment. After a median follow-up period of 3.3 years, 128 had newly diagnosed PAD. Of these, 65 presented with CLI, and 25 underwent amputation or died from PAD. Patients presenting with CLI had more below-the-knee (52%) and multi-level (41%) disease, and completely occluded segments (41%), and higher risk for amputation or PAD-related death compared with patients without CLI (27.7% vs 9.5%, P = .01). After multivariate adjustment, disability, diabetes mellitus, current smoking and atrial fibrillation were significantly associated with newly diagnosed CLI.ConclusionsPatients undergoing hemodialysis had higher rates of newly diagnosed CLI than the general population. Those with disabilities, diabetes mellitus, smoking and atrial fibrillation may require careful examination for PAD. Trial registration: Hsinchu VA study, ClinicalTrials.gov identifier: NCT04692636.

Restenosis remains a significant problem after angioplasty of hemodialysis vascular access. Both experimental and clinical studies have shown a protective effect of antioxidants against post-angioplasty restenosis. A prospective, randomized, feasibility study was conducted to investigate the effect of ascorbic acid to prevent restenosis. Ninety-three hemodialysis patients were randomized into three groups after angioplasty: placebo (n = 31), 300 mg ascorbic acid (n = 31), and 600 mg ascorbic acid (n = 31), treated intravenously 3 times per week for 3 months. Eighty-nine completed the clinical follow-up, and 81 had angiographic follow-up. In the angiographic follow-up, the mean (stand deviation) late loss of luminal diameter for the placebo, 300 mg, and 600 mg groups were 3.15 (1.68) mm, 2.52 (1.70) mm (P = 0.39 vs. placebo group), and 1.59 (1.67) mm (P = 0.006, vs. placebo group), with corresponding angiographic binary restenosis of 79%, 67% (P = 0.38 vs. placebo group), and 54% (P = 0.08 vs. placebo group). The post-interventional primary patency rates at 3 months were 47%, 55% (P = 0.59 vs. placebo group), and 70% (P = 0.18 vs. placebo group) for placebo, 300 mg, and 600 mg groups. Our results demonstrated that intravenous 600 mg ascorbic acid was a feasible therapy and might attenuate restenosis after angioplasty; however, its effect on post-interventional primary patency was modest.

In this investigation, to reach a widely wavelength-selectable and stable single-longitudinal-mode (SLM) erbium-doped fiber (EDF) ring laser, the unpumped EDF-based saturable absorber (SA) and dual-ring structure are used simultaneously for thickly multi-longitudinal-mode (MLM) suppression. The dual-ring scheme can spread the operation range of gain medium from 1520.0 to 1580.0 nm only by using a C-band erbium-doped fiber amplifier (EDFA). Moreover, the dual-ring scheme and EDF-based SA also could suppress the MLM noise for SLM oscillation. In the tuning range, the Lorentzian 3 dB linewidth is also obtained between 15 and 22 kHz in the wavelength range.

BACKGROUND: Frailty has been associated with mortality and adverse cardiovascular outcomes in patients with hemodialysis (HD), however the relevance of frailty on the outcomes of HD vascular access remains unclear. METHODS: We enrolled a cohort of patients with prevalent HD between August 2018 and November 2018. The presence of 5 frailty phenotypes was determined at enrollment, using the modified Fried’s criteria. Data regarding vascular access events or mortality were linked to prospectively collected data up to 24 months after enrollment. RESULTS: Of the 382 patients screened, 313 were recruited in the final analysis. The participants’ mean age was 66 years, and 42.5% were female. Among all participants, 40.3% were determined to be frail and 29.4% pre-frail. The frail phenotype was associated with age, female gender, lower body mass index, unemployment, lower education level, and higher dialysis clearance. During the follow-up period (median, 24 months), 112 patients had vascular access events (non-frail, 27.4%; pre-frail, 35.9%; frail, 46.1%; p = 0.003) and 45 patients experienced thrombosis of the vascular access (non-frail, 4.2%; pre-frail, 9.8%; frail, 18.3%; p = 0.002). Cox regression analysis showed that frail patients had a 2.2-fold higher risk of experiencing vascular access events than non-frail patients [hazard ratio (HR): 2.205, 95% confidence interval (CI): 1.377-3.532, p = 0.001], but the association was not significant (HR: 1.634, 95% CI: 0.938-2.848, p = 0.082) after multivariate adjustment. CONCLUSIONS: The frail phenotype is common in Taiwanese patients who undergo maintenance HD and is associated with adverse outcomes of dialysis vascular access.

Background: Angioplasty-related vessel rupture is a common complication of interventions. The effect of covered stents to treat venous rupture has been evaluated in smaller series, but should be further evaluated. Objective: To report the immediate outcomes and patency rates of a covered stent to rescue angioplasty-related venous rupture of hemodialysis vascular access. Methods: From January 2013 to December 2018, 113 procedures complicated with vessel ruptures were retrospectively analyzed from a prospectively collected database of 8146 hemodialysis access interventions. The strategies to salvage vessel ruptures were based on the discretion of the treating physicians. Follow-up outcomes were obtained via review of the angiographic images, procedural notes, and medical and dialysis records within 12 months after the index procedures. Results: A total of 52 vessel ruptures (21 fistulas, 31 grafts) salvaged by using Viabahn covered stents were enrolled. Vessel ruptures developed in 28 (53.8%) thrombectomy procedures. Device success was achieved in all procedures (100%) and clinical success was achieved in 50 (96.2%). The primary patency of the stent area was 66.0% at 6 months and 50.0% at 12 months. The primary patency of the entire access circuit was 27.4% at 6 months and 16.0% at 12 months. The most common cause of access circuit primary patency loss was thrombotic occlusion for graft accesses and restenosis at stent area for native accesses. Eleven vascular accesses were abandoned within 12 months after vessel ruptures, and the secondary patency rate of the entire access circuit was 78.0% at 12 months. Conclusions: Treatment of angioplasty-induced vessel rupture of hemodialysis vascular accesses by using Viabahn covered stents has good immediate outcomes and patency results at the stent area. Nonetheless, the patency rate of entire access circuit was still below the threshold recommended by guidelines.

In the work, we propose and investigate a real-time optical wireless communication (OWC) system with 1 Gbps on–off keying (OOK) traffic rate for indoor and outdoor transmissions. Here, 1 Gbps OWC traffic with error-free operation can be achieved indoors under the free space transmission length of 500 m based on the simulation and experimental results. In addition, 952, 904, 476 Mbps throughput rates of proposed real-time OWC system are measured outdoors after passing through the wireless transmission lengths of 120, 300 and 500 m, respectively.

In this work, we demonstrate an integrated optical baseband, free space optical (FSO) communication and millimeter-wave (MMW) traffics through the present passive optical network (PON) architecture by utilizing single wavelength for broadcasting triple-play services. In the execution, we exploit 10 Gbit/s on-off keying (OOK) modulation on 10 GHz Mach-Zehnder modulator (MZM) to produce the downstream baseband signal. And the 10 Gbit/s baseband signal also can cause FSO traffic within the forward error correction (FEC) target after 25 km fiber and 160 m free space transmissions. Moreover, we can utilize the fiber to the extension (FTTE) scheme to provide the 36.42 GHz MMW with 10 Gbit/s OOK data after 25 km fiber link and 8 km extended fiber transmission.

We present and demonstrate a stabilized and selectable erbium-doped fiber (EDF) ring laser according to the proposed EDF saturable absorber (SA) and self-injected method to achieve single-longitudinal-mode (SLM) output and narrow the laser linewidth simultaneously. The 60-nm continuous wave (CW) tunability range from 1525.0 to 1585.0 nm is also accomplished here. Moreover, the output performance of wavelength stability and laser linewidth are also performed experimentally.

In this paper, to accomplish the broadly wavelength tunability and single-longitudinal-mode (SLM) operation of erbium-doped fiber (EDF) based laser, the multiple-ring structure is designed and executed. The output power of −7.3 to 5.1 dBm and optical signal to noise ratio (OSNR) of 31.5 to 36.7 dB/0.06 nm are obtained for the proposed EDF laser over the tuning range of 1520.0–1590.0 nm based on the C-band EDF gain medium. In addition, the Lorentzian linewidth of 14.9 to 20.4 kHz is also attained.

A broadband and steady erbium-doped fiber (EDF) quad-fiber-ring (QFR) laser by exploiting C-band EDF gain medium is proposed and explored. To achieve the single-longitudinal-mode (SLM) behavior, the designed QFR structure can cause the mode-filter action for filtering the multiply side-mode noise. Besides, the QFR also can spread the available wavelength-operated range from 1520.0 to 1604.0 nm. Here, the related optical signal to noise ratio (OSNR), output power, laser linewidth and stability characteristic of proposed EDF laser have been also performed and discussed.

Objective/Background Endovascular repair (EVAR) of mycotic aortic aneurysm (MAA) has become an alternative treatment for high risk patients. The aim of this study was to evaluate long-term survival and outcomes. Methods Retrospective analysis of 40 consecutive patients with MAAs undergoing EVAR and subsequent intravenous antibiotic treatment between September 2009 and April 2015. Follow-up was truncated on 30 April 2015. Uni- and multivariate logistic regression were used to assess risk factors of adverse outcomes. Cumulative survival was calculated using the Kaplan–Meier method. Results Median age at repair was 73 years (range 48–88 years) and 31 (77%) were men. Eleven (27%) patients were infected with Salmonella, 12 (30%) with non-Salmonella species, and 17 (42%) had negative cultures. Anatomical locations included the aortic arch/thoracic area in 10 (25%), the paravisceral area in seven (17%), and the infrarenal area in 23 (57%). Ten (25%) patients presented with aneurysm rupture and underwent emergency repair. Median follow-up was 25 months (range 1–69 months). Cumulative 1 and 5 year survival rates were 71% and 53%, respectively. Persistent or recurrent infection occurred in 20% (n = 8). Patients with persistent infection were treated with long-term medical therapy, but all died (75%; n = 6) within 6 months of repair. No survival difference was found between patients with or without Salmonella infections. However, there was a trend toward better survival in culture negative patients. Conclusion EVAR of MAA is an acceptable alternative treatment of MAA. However, persistent infection after endovascular treatment does occur and is often fatal without surgical treatment.

Ion variable measurements before and after ECLS. (DOCX 64Â kb)

Body weight, arterial blood gas, hematocrit, and hemodynamic variables showed in sham group (n = 2). (DOCX 71 kb)

Background Extracorporeal life support (ECLS) systems are life-saving devices used for treating patients with severe cardiopulmonary failure. In this study, we implemented a rat model of ECLS without the administration of inotropes or vasopressors. Methods The rats underwent 5 min of untreated asphyxial cardiac arrest and were resuscitated by ECLS for 30 min. The right external jugular vein and right femoral artery were separately cannulated to the ECLS outflow and inflow, respectively. Thereafter, ECLS was terminated, wounds were closed, and mechanical ventilation was provided for another 90 min. Subsequently, blood gas and hemodynamic analyses were performed. The plasma levels of C-reactive protein (CRP), interleukin (IL)-6, IL-10, and tumor necrosis factor-alpha (TNF-α) were measured 120 min after reperfusion. Results The metabolic rate of lactate in the group of asphyxial cardiac arrest rescued by ECLS was slow; therefore, the pH at 120 min after reperfusion was significantly lower in this group than that in the group of normal rats treated with ECLS. The hemodynamic data showed no between-group differences. The plasma levels of CRP, IL-6, IL-10, and TNF-α increased after ECLS treatment. Conclusions We successfully established a rodent ECLS model, which might be a useful approach for studying the pathophysiology induced by ECLS under clinical conditions. Electronic supplementary material The online version of this article (doi:10.1186/s12872-017-0558-6) contains supplementary material, which is available to authorized users.

Current endografts, which were designed primarily for the descending aorta, have significant limitations when used in the ascending aorta. We report our initial experience using the transapical endovascular approach to treat an ascending aortic dissection with a table-tailored commercial stent graft. doi: 10.1111/jocs.12449 (J Card Surg 2014;29:824–826)

Objectives The value of dimerized plasmin fragment D in the clinical monitoring during the catheter-directed thrombolysis in patients with acute deep vein thrombosis is not known. Methods Dimerized plasmin fragment D levels in 24 patients with acute deep vein thrombosis undergoing catheter-directed thrombolysis were prospectively evaluated. The plasma dimerized plasmin fragment D level was measured serially before and at every 12 h during catheter-directed thrombolysis for 24 h. Technical success was defined as restoration of patency and flow with less than 50% residual thrombus by surveillance rotational venography. Results Technical success was achieved in 79.2% (19 of 24) of the treated limbs after catheter-directed thrombolysis. In univariate analysis, there was significant elevation of the dimerized plasmin fragment D at 12th h after starting the catheter-directed thrombolysis ( P Conclusions Catheter-directed thrombolysis is safe and effective for restoration of blood flow in patients with acute deep vein thrombosis. Dimerized plasmin fragment D value greater than 18.4 µg/ml at the 12th h after starting catheter-directed thrombolysis had a high predictive rate of greater than 50% lysis at the end of catheter-directed thrombolysis.

Purpose In addition to having a lipid-lowering effect, statins also have an anti-inflammatory effect that may reduce allograft dysfunction by preventing cardiac allograft vasculopathy (CAV) and play an immunomodulatory role. We studied the effect of statins on cardiac allograft survival at the National Taiwan University Hospital (NTUH). Materials and Methods We retrospectively reviewed the patients undergoing heart transplantation at NTUH in the last 6 years. After transplantation, all patients received biochemical monitoring every month and echocardiographic examination regularly at NTUH. Protocol biopsy was performed in all except 18 pediatric patients. All patients received immunosuppressants, including tacrolimus or cyclosporine, everolimus or mycophenolate acid, and prednisolone. They were divided into statin and nonstatin groups according to whether or not a statin was taken. Results At NTUH, from 2007 to 2012, 168 heart transplantations were performed. The ages of the patients ranged from 6 to 74 years old with male predominance. The etiology was mainly dilated cardiomyopathy (52.4%) and ischemic cardiomyopathy (39.3%), including 7 retransplantations from severe CAV with heart failure. Twenty-three patients (17%) suffered from acute rejection. The overall 1-year actuarial survival rate was 86% ± 2% and the 5-year survival rate was 79% ± 3%. Seventy-eight patients (57.4%) took statins and the statin group has a better 5-year survival rate and freedom from cardiac death survival rate ( P Conclusion Our study showed that the use of statins after transplantation was associated with better survival.