Visual learning in tethered bees modifies flight orientation and is impaired by epinastine.

Visual-orientation learning of a tethered flying bee was investigated using a flight simulator and a novel protocol in which orientation preference toward trained visual targets was assessed in tests performed before and after appetitive conditioning. Either a blue or a green rectangle (conditioned stimulus, CS) was associated with 30% sucrose solution (unconditioned stimulus, US), whereas the other rectangle was not paired with US. Bees were tested in a closed-looped flight simulator 5 min after ten pairings of the US and CS. Conditioned bees were preferentially oriented to the CS after such training. This increase in preference for CS was maintained for 24 h, indicating the presence of long-term memory. Because the total orienting time was not altered by conditioning, conditioning did not enhance orientation activity itself but increased the relative time for orientation to CS. When 0.4 or 4 mM epinastine (an antagonist of octopamine receptors) was injected into the bee's head 30 min prior to the experiment, both short- and long-term memory formation were significantly impaired, suggesting that octopamine, which is crucial for appetitive olfactory learning in insects, is also involved in visual orientation learning.

Prediction of Wound Recurrence in Patients With Chronic Limb-Threatening Ischemia Undergoing Endovascular Treatment.

PURPOSE: Chronic limb-threatening ischemia due to isolated below-the-knee lesions is a factor associated with wound recurrence. However, there is a lack of data regarding wound recurrence in such cases. This study aimed to determine the predictors of wound recurrence in patients with chronic limb-threatening ischemia undergoing endovascular treatment. PATIENTS AND METHODS: This was a single-center, retrospective, observational study. We enrolled 152 consecutive patients with chronic limb-threatening ischemia (172 limbs) who achieved complete wound healing after undergoing endovascular treatment for isolated below-the-knee lesions between February 2008 and December 2017. Of these, the wound had recurred in 56 limbs (33%), and we divided the patients into 2 groups based on wound recurrence. We evaluated the recurrence rate of chronic limb-threatening ischemia and predictors of wound recurrence. Wound recurrence was defined as recurrence of the wound within 2 years of complete wound healing. RESULTS: Patients' backgrounds were similar in both groups, including mean age (72±9 vs 72±11; p=0.76) and hemodialysis (43% vs 40%; p=0.66). Pre-pedal arch type 2 (52% vs 8%; p<0.01), infrapopliteal grade 4 of the Global Limb Anatomic Staging System (77% vs 59%; p=0.02), and Wound, Ischemia, and foot Infection criteria stage 4 (43% vs 28%; p=0.04) were more common in the wound recurrence group. Multivariate Cox proportional hazard analysis identified pre-pedal arch type 2 (hazard ratio, 5.28; 95% confidence interval, 3.08-9.10; p<0.01) and Wound, Ischemia, and foot Infection criteria stage 4 (hazard ratio, 1.98; 95% confidence interval, 1.15-3.36; p=0.01) as predictors of wound recurrence after complete wound healing. CONCLUSION: Pre-pedal arch type 2 and Wound, Ischemia, and foot Infection classification system stage 4 were associated with wound recurrence in patients with chronic limb-threatening ischemia who achieved complete wound healing after undergoing endovascular treatment for isolated below-the-knee lesions.

Framework-Directed Amino-Acid Insertions Generated over 55-Fold Affinity-Matured Antibody Fragments That Enabled Sensitive Luminescent Immunoassays of Cortisol.

We generated three single-chain Fv fragments (scFvs) specific to cortisol according to our original affinity-maturation strategy and verified their utility in developing immunoassays. These scFv mutants (m-scFvs) had insertion of one, four, or six amino acid(s) in the framework region 1 of the VH-domain and showed >55-fold higher affinity (Ka, 2.0 - 2.2 × 1010 M-1) than the unmodified scFv (wt-scFv). Each m-scFv was fused with NanoLuc luciferase (NLuc) for the use in enzyme-linked immunosorbent assays (ELISAs). In these ELISA, the m-scFv-NLuc fusions were competitively reacted with immobilized cortisol residues and cortisol standards, and then the bound NLuc activity was monitored luminometrically. The luminescent ELISAs generated dose-response curves with extremely low midpoints (approx. 3 pg/assay) and were >150-fold more sensitive than the colorimetric ELISAs using wt-scFv and >8000-fold more sensitive than the ELISA using the parental native antibody. The luminescent ELISAs showed acceptable cross-reactivity patterns with related steroids, and the determination of control sera afforded cortisol levels in the reference range with satisfactory parallelism.

Impact of "black rock" on clinical outcomes after endovascular therapy for de novo calcified femoropopliteal lesions.

The relationship between severity of calcification and clinical outcomes after endovascular therapy (EVT) for femoropopliteal lesions is well known. We often encounter dense calcifications in our daily practice, which are darker than normal calcifications on angiography. Accordingly, we named it "black rock" (BR), and investigated its impact on clinical outcomes after EVT. We retrospectively analyzed 677 lesions in 495 patients who underwent EVT for de novo calcified femoropopliteal lesions at our hospital between April 2007 and June 2020. BR is defined as a calcification which is 1 cm or more in length, occupies more than half of the vessel diameter, and appears darker than the body of the femur on angiography. Propensity score matching analysis was performed to compare clinical outcomes between lesions with BR [BR (+) group] and without BR [BR (-) group]. A total of 119 matched pairs of lesions were analyzed. Primary patency at 2 years was significantly lower in the BR (+) group than in the BR (-) group (48% vs. 75%, p = .0007). Multivariate analysis revealed that the presence of BR [hazard ratio (HR) = 2.23, 95% confidence interval (CI); 1.48-3.38, p = .0001], lesion length (HR = 1.03, 95%CI; 1.00-1.06, p = .0244), and no scaffold use (HR = 1.58, 95%CI; 1.06-2.36, p = .0246) were predictors of restenosis. The presence of BR is independently associated with clinical outcomes after EVT for de novo calcified femoropopliteal lesions.

Procedural results and in-hospital outcomes of percutaneous coronary intervention for chronic total occlusion in patients with reduced left ventricular ejection fraction: Sub-analysis of the Japanese CTO-PCI Expert Registry.

OBJECTIVES: To evaluate the procedural results and in-hospital outcomes of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) in patients with reduced left ventricular ejection fraction (LVEF). BACKGROUND: While the technical success of general CTO-PCI has improved, CTO-PCI patients with reduced LVEF remain at high-risk for adverse events. METHODS: The data of 820 patients with LVEF ≤ 35% (Group 1), 1816 patients with LVEF = 35%-50% (Group 2), and 5503 patients with LVEF ≥ 50% (Group 3), registered in the Japanese CTO-PCI Expert Registry from January 2014 to December 2019, were retrospectively analyzed. The primary endpoint was in-hospital major adverse cardiac or cerebrovascular events (MACCEs), including death, myocardial infarction, stent thrombosis, stroke, and emergent revascularization. Secondary endpoints included procedural details, guidewire success, and technical success. RESULTS: There were no differences in guidewire and technical success rates between the groups. In-hospital MACCEs was significantly higher in Group 1 (Group 1 vs. Group 2 vs. Group 3: 3.4% vs. 1.7% vs. 1.5%, p = 0.001) and was especially driven by death (1.3% vs. 0.3% vs. 0.1%, p < 0.001) and stroke (0.7% vs. 0.2% vs. 0.2%, p = 0.007). Multivariate analysis showed that LVEF ≤ 35% (odds ratio [OR]; 1.58, 95% confidence interval [CI]; 1.04-2.41, p = 0.03) and New York Heart Association (NYHA) class ≥ 3 (OR; 2.01, 95% CI; 1.03-3.93, p = 0.04) were predictors of in-hospital MACCEs. CONCLUSIONS: In-hospital MACCEs were significantly higher in patients with LVEF ≤ 35%. LVEF ≤;35% and NYHA class ≥ 3 were predictors of in-hospital MACCEs after CTO-PCI.

Predictive performance of J-Calc-CTO score for guidewire crossing through chronic total occlusion lesions within 30 minutes: J-CTO score modified by computed tomography coronary angiography.

The original J-CTO score predicts the difficulty of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) lesions, but the grade of calcification has not been fully evaluated. We examined 137 patients (141 CTO lesions) who underwent coronary computed tomography angiography (CTA) pre-PCI between October 2016 and October 2021. They were randomly divided into derivation (n = 94) and validation (n = 47) groups. The degree and distribution of calcification in the occluded segment were assessed using CTA. The calcified index was defined as calcium volume divided by the length of the occluded segment. We created the J-Calc-CTO score consisting of calcification parameters associated with 30-min wire crossing in the derivation group. The validity of the J-Calc-CTO score was compared with that of the original J-CTO score using c-statistics. The procedural success rate was 96%, and 30-min wire crossing during the procedure was achieved in 29%. Dense calcification (calcified-index >12) (odds ratio [OR]: 4.63; 95% confidence interval [CI]: 1.24-22.2; p = 0.04) and calcification in the center of the lumen (OR: 7.25; 95% CI: 1.48-32.1; p = 0.02) were independently associated with 30-min wire crossing as variables evaluated using CTA. The J-Calc-CTO score was created by adding 1 point to the two parameters in place of "calcification" in the original J-CTO score. The J-Calc-CTO score showed a higher predictive value of 30-min wire crossing than the J-CTO score in the derivation (c-statistics; 0.836 vs. 0.670; p > 0.01) and validation groups (c-statistics; 0.879 vs. 0.767, p > 0.01). The degree and distribution of calcification evaluated using CTA refined the predictive value of the original J-CTO score for 30-min wire crossing.

Scoring Model to Predict Major Amputation in Patients With Chronic Limb-Threatening Ischemia at Wound, Ischemia, and Foot Infection Clinical Stage 4 After Endovascular Therapy.

PURPOSE: We investigated the predictors of major amputation (MA) at 1 year and prepared a scoring model to stratify the clinical outcomes of chronic limb-threatening ischemia (CLTI) patients at wound, ischemia, and foot infection (WIfI) clinical stage 4 after endovascular therapy (EVT). MATERIALS AND METHODS: This study was a retrospective, observational study performed at a single center. A total of 353 CLTI patients (390 limbs) were treated with EVT between April 2007 and December 2016. Among these, limbs at WIfI clinical stages 1, 2, and 3 were excluded, and 194 limbs at WIfI clinical stage 4 (49.7%) were enrolled. The primary endpoint was major amputation (MA) free rate at 1 year. Predictors of MA at 1 year was evaluated by Cox proportional hazard analysis. RESULTS: At 1 year, the incidence of MA was 18.0% (35 limbs). Cox proportional hazard analysis revealed that hemodialysis (hazard ratio [HR] 2.63; 95% confidence interval [CI], 1.24-5.58; p=0.012), fI3 (HR 2.54; 95% CI, 1.28-5.06; p=0.008), toe wounds (HR 0.29; 95% CI, 0.094-0.88; p=0.029), and visible blood flow to the wound (HR 0.43; 95% CI, 0.21-0.89; p=0.023) were associated with MA. We assigned 1 point for positive predictors of MA, hemodialysis, and fI3; 1 point was deducted for negative predictors of MA, toe wounds, and visible blood flow to the wound. A score of -2 or -1, was defined as the low-risk group, 0 was defined as the intermediate-risk group, and +1 or +2 were defined as the high-risk group. At 1 year, MA free rate, wound healing rate, and amputation-free survival rate were stratified according to a scoring model. MA free rate was 96.6% in low-risk, 72.4% in intermediate-risk, and 67.3% in high-risk (p<0.001); wound healing rate was 67.8% in low-risk, 27.6% in intermediate-risk, and 4.1% in high-risk (p<0.001); amputation-free survival rate was 65.3% in low-risk, 44.8% in intermediate-risk, and 18.4% in high-risk (p<0.001). CONCLUSIONS: The scoring model based on the predictors of MA stratified clinical outcomes in CLTI patients at WIfI clinical stage 4.

Retrieving Dissociation-Resistant Antibody Mutants: An Efficient Strategy for Developing Immunoassays with Improved Sensitivities.

Previously, we generated high-affinity antibody mutants that enabled sensitive immunoassays by exploring diverse libraries of single-chain Fv fragments (scFvs) displayed on bacteriophage. To isolate rarely-occurring desirable clones, "panning" has commonly been performed but is often unsuccessful. Therefore, we previously developed a clonal array profiling (CAP) method, wherein scFv-displaying phage (scFv-Ph) clones in a library were examined individually regarding their ability to target antigens immobilized on microwells. Clones that showed strong reactivity were recovered via dissociation using an acidic treatment. The CAP successfully discovered cortisol-specific scFvs showing 17-31-fold improved Ka from libraries generated via site-directed insertions in a prototype anti-cortisol scFv (wt-scFv; Ka, 3.6 × 108 M-1), but their Ka did not exceed 1.1 × 1010 M-1. In this study, to break this possible affinity ceiling, we devised a new system employing a dissociation-independent recovery. scFv-Phs were individually reacted to target antigen (cortisol) immobilized on microwells via a linker containing a disulfide bond. Following acidic and basic treatments to eliminate scFv-Phs with "ordinary affinities," dissociation-resistant scFv-Phs remaining on the microwells were retrieved via reductive cleavage of the disulfide bonds. This system allowed for a straightforward and efficient discovery of scFv mutants with 33-56-fold increased Ka (1.2-2.0 × 1010 M-1), exceeding the previous affinity ceiling. These scFvs enabled an enzyme-linked immunosorbent assay for cortisol with 18-51-fold higher sensitivity than the assay performed using wt-scFv.

More than 370-Fold Increase in Antibody Affinity to Estradiol-17ß by Exploring Substitutions in the VH-CDR3.

Antibodies that specifically target biomarkers are essential in clinical diagnosis. Genetic engineering has assisted in designing novel antibodies that offer greater antigen-binding affinities, thus providing more sensitive immunoassays. We have succeeded in generating a single-chain Fv fragment (scFv) targeted estradiol-17ß (E2) with more than 370-fold improved affinity, based on a strategy focusing the complementarity-determining region 3 in the VH domain (VH-CDR3). Systematic exploration of amino acid substitutions therein, using a clonal array profiling, revealed a cluster of four substitutions, containing H99P and a serial substitution E100eN-I100fA-L100gQ that lead to a 90-fold increase in E2-binding affinity. This substitution quartet in the VH-CDR3, combined with the substitution cluster I29V/L36M/S77G in the VL domain, resulted in a scFv fragment with a further increase in the affinity (Ka, 3.2 × 1010 M-1). This enabled a highly sensitive enzyme-linked immunosorbent assay capable of detecting up to 0.78 pg/assay. The current study has, thus, focused on the significance of reevaluating the potential of mutagenesis targeting the VH-CDR3, and encouraging the production and use of engineered antibodies that enable enhanced sensitivities as next-generation diagnostic tools.

Purification of Emu IgY for Therapeutic and Diagnostic Use Based on Monoclonal Secondary Antibodies Specific to Emu IgY.

The emu is the second largest ratite; thus, their sera and egg yolks, obtained after immunization, could provide therapeutic and diagnostically important immunoglobulins with improved production efficiency. Reliable purification tools are required to establish a pipeline for supplying practical emu-derived antibodies, the majority of which belongs to the immunoglobulin Y (IgY) class. Therefore, we generated a monoclonal secondary antibody specific to emu IgY. Initially, we immunized an emu with bovine serum albumin multiply haptenized with 2,4-dinitrophenyl (DNP) groups. Polyclonal emu anti-DNP antibodies were partially purified using conventional precipitation method and used as antigen for immunizing a BALB/c mouse. Splenocytes were fused with myeloma cells and a hybridoma clone secreting a desirable secondary antibody (mAb#2-16) was established. The secondary antibody bound specifically to emu-derived IgY, distinguishing IgYs from chicken, duck, ostrich, quail, and turkey, as well as human IgGs. Affinity columns immobilizing the mAb#2-16 antibodies enabled purification of emu IgY fractions from sera and egg yolks via simple protocols, with which we succeeded in producing IgYs specific to the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) spike protein with a practical binding ability. We expect that the presented purification method, and the secondary antibody produced in this study, will facilitate the utilization of emus as a novel source of therapeutic and diagnostic antibodies.

Two-year intermittent exposure of a multiwalled carbon nanotube by intratracheal instillation induces lung tumors and pleural mesotheliomas in F344 rats.

BACKGROUND: A mounting number of studies have been documenting the carcinogenic potential of multiwalled carbon nanotubes (MWCNTs); however, only a few studies have evaluated the pulmonary carcinogenicity of MWCNTs in vivo. A 2-year inhalation study demonstrated that MWNT-7, a widely used MWCNT, was a pulmonary carcinogen in rats. In another 2-year study, rats administered MWNT-7 by intratracheal instillation at the beginning of the experimental period developed pleural mesotheliomas but not lung tumors. To obtain data more comparable with rats exposed to MWNT-7 by inhalation, we administered MWNT-7 to F344 rats by intratracheal instillation once every 4-weeks over the course of 2 years at 0, 0.125, and 0.5 mg/kg body weight, allowing lung burdens of MWNT-7 to increase over the entire experimental period, similar to the inhalation study. RESULTS: Absolute and relative lung weights were significantly elevated in both MWNT-7-treated groups. Dose- and time-dependent toxic effects in the lung and pleura, such as inflammatory, fibrotic, and hyperplastic lesions, were found in both treated groups. The incidences of lung carcinomas, lung adenomas, and pleural mesotheliomas were significantly increased in the high-dose group compared with the control group. The pleural mesotheliomas developed mainly at the mediastinum. No MWNT-7-related neoplastic lesions were noted in the other organs. Cytological and biochemical parameters of the bronchoalveolar lavage fluid (BALF) were elevated in both treated groups. The lung burden of MWNT-7 was dose- and time-dependent, and at the terminal necropsy, the average value was 0.9 and 3.6 mg/lung in the low-dose and high-dose groups, respectively. The number of fibers in the pleural cavity was also dose- and time-dependent. CONCLUSIONS: Repeated administration of MWNT-7 by intratracheal instillation over the 2 years indicates that MWNT-7 is carcinogenic to both the lung and pleura of rats, which differs from the results of the 2 carcinogenicity tests by inhalation or intratracheal instillation.

Scoring model to predict low image quality of drug-eluting stent evaluated by computed tomography coronary angiography.

Evaluation of in-stent restenosis (ISR) by computed tomography coronary angiography (CTCA) is less invasive but often impossible. We aimed to create a scoring model for predicting which drug-eluting stents (DES) cannot be evaluated with CTCA. We enrolled 757 consecutive implanted DES assessed with CTCA. Non-diagnostic evaluation was defined as poor/not evaluative by two different observers. These stents were randomly divided into a derivation (n = 379) and validation (n = 378) group. In the derivation group, we assessed predictors using logistic regression analysis and created a scoring model that would stratify non-diagnostic evaluation of DES-ISR. The validity of this scoring model was evaluated in the validation group using receiver-operating characteristic analysis. The percentage of non-diagnostic stents was 19/21% in the derivation/validation group (p = 0.71). Non-diagnostic evaluation was independently associated with implanted stent diameter (2.25-2.5. vs. 2.5-3 vs. > 3.0 mm), severe calcification, stent-in-stent lesion, and type of DES (stainless vs. CoCr vs. PtCr) in the derivation group. The predicting system of implanted DES non-diagnostic by CTCA (PIDENT) for non-diagnostic evaluation, including these four baseline factors, was derived (C-statistic = 0.86 in derivation group, cutoff: 8 points). The PIDENT score had a high predictive value for non-diagnostic DES in the validation model (C-statistic = 0.87, sensitivity 86%, specificity 74%, cutoff 8 points, p < 0.001). The PIDENT score, consisting of baseline characteristics including implanted stent diameter, severe calcification, stent-in-stent lesion, and type of DES, could identify non-diagnostic evaluation of DES-ISR with CTCA. The PIDENT score was valuable in reducing nonevaluable and meaningless CTCA for DES-ISR.

Efficacy of the novel technique HIRANODOME in preventing distal embolization during endovascular treatment of femoropopliteal lesions.

OBJECTIVES: The efficacy and clinical outcomes of a novel technique "HIRANODOME" (Interim hemostatic technique with HIgh pressure for Regional blood flow in the superficial femoral Artery, NOninvasive Distal protection Occlusion MEthod) in preventing distal embolization during endovascular treatment (EVT) of femoropopliteal lesions were evaluated. BACKGROUND: Distal embolization of femoropopliteal lesions may worsen limb ischemia or cause limb loss. Conventional filter wires are cumbersome and expensive and may cause vessel injury. HIRANODOME can, therefore, be a feasible and noninvasive alternative. METHODS: Between April 2007 and August 2018, 94 consecutive patients who underwent EVT for femoropopliteal lesions along with anticipated distal embolization were identified. About 9 out of these 94 patients were excluded due to filter device use and 8 were excluded due to acute limb ischemia. Consequently, 77 patients using HIRANODOME for distal protection were included. HIRANODOME involved wrapping the Tometakun around the knee to enable external compression of the popliteal artery, thereby blocking the blood flow. The evaluation items were 30-day mortality, 30-day major amputation, prevention from distal embolization, and thrombus capture rate. RESULTS: The mean age was 74.4 ± 10.3 years, 53.2% were men, 55.8% were diabetic, and 9.1% were on hemodialysis. The mean lesion length was 199.5 ± 94.4 mm; 79.2% were class C/D lesions (TASC II classification). The 30-day mortality and major amputation rates were 1.9 and 1.0%, respectively. The rate of prevention of distal embolization or no-flow/slow-flow phenomenon was 93.4%. Capture of thrombus was observed in 66 lesions (62.3%). CONCLUSIONS: The HIRANODOME technique was effective in preventing distal embolization during EVT of femoropopliteal lesions.

Stentless Strategy by Drug-Coated Balloon Angioplasty following Directional Coronary Atherectomy for Left Main Bifurcation Lesion.

AIMS: We aimed to evaluate the efficacy of stentless strategy by drug-coated balloon (DCB) angioplasty following directional coronary atherectomy (DCA) for left main (LM) bifurcation lesions. METHODS: A total of 38 patients who underwent DCB angioplasty following DCA for LM bifurcation lesions were retrospectively enrolled. The primary endpoint was target vessel failure (TVF) at 12 months. Secondary endpoints included procedure-related major events during the hospitalization, major adverse cardiac events at 12 months, ischemia-driven target lesion revascularization (TLR) at 12 months, and bleeding complications defined as the Bleeding Academic Research Consortium criteria ≥2 at 12 months. RESULTS: Among these 38 lesions, 31 lesions were de novo LM bifurcation lesions and 7 lesions were stent edge restenosis at the left anterior descending (LAD) ostium. The mean % plaque area (%PA) after DCA was 44.0 ± 7.4%. TVF at 12 months occurred in 1 lesion (3.2%) of de novo LM bifurcation lesion and in 3 lesions (42.9%) of stent edge restenosis at the LAD ostium. All events of TVF were ischemia-driven TLR by percutaneous coronary intervention. Among 4 TLR cases, %PA after DCA was high (55.9%) in the de novo LM bifurcation lesions; on the other hand, %PA after DCA was low (42.4%, 38.7%, and 25.7% in the 3 cases) in stent edge restenosis at the LAD ostium. No procedure-related major events were observed during hospitalization. There was no cardiac death, no myocardial infarction, no coronary artery bypass grafting, and no bleeding complications at 12 months. CONCLUSIONS: Stentless strategy by DCB angioplasty following DCA for de novo LM bifurcation lesions resulted in acceptable outcomes. On the other hand, its efficacy was limited for stent edge restenosis at the LAD ostium even after aggressive debulking by DCA.

Vascular Response after Directional Coronary Atherectomy for Left Main Bifurcation Lesion.

AIMS: To evaluate the vascular response after directional coronary atherectomy (DCA) for left main (LM) bifurcation lesion. METHODS: This study was a retrospective, single-center study enrolling 31 patients who underwent stentless therapy using DCA followed by drug-coated balloon (DCB) angioplasty for LM bifurcation lesion. We compared intravascular ultrasound (IVUS) findings before and after DCA. RESULTS: After DCA, the lumen and vessel areas significantly increased, whereas the plaque area (PA) and %PA were significantly reduced. When the lesions were divided into small vessel and large vessel groups using the median value of the vessel area, the maximum balloon pressure of the DCA catheter was greater in the large vessel group. Changes in the lumen and vessel areas were also significantly greater in the large vessel group. On the other hand, the changes in PA and %PA were similar between groups. CONCLUSIONS: The main vascular responses associated with lumen enlargement after DCA were plaque reduction and vessel expansion. Contribution of vessel expansion to lumen enlargement was larger than the effect of plaque reduction in large vessel lesions.

ULSOSEAL Technique: A Unique Technique to Achieve Hemostasis Using ExoSeal in High-Risk Patients after Common Femoral Artery Puncture.

This study aimed to assess the safety and feasibility of the ULtrasound-guided uSe Of exoSEAL technique (ULSOSEAL technique) in patients at a high risk of complications following the use of ExoSeal. ExoSeal is a novel, completely extravascular hemostatic device that can treat punctures of the common femoral artery; however, it is not preferable for use in cases that require hemostasis of complex puncture sites. From November 2019 to August 2020, the ULSOSEAL technique was performed in 35 patients with implanted stents (6 patients, 17%), severe calcification (32 patients, 91%), and plaque (7 patients, 20%) around the puncture site; the presence of these conditions is usually undesirable when using ExoSeal. The antegrade approach was used in 22 patients (71%). The size of the ExoSeal used was 5 Fr (13 patients, 37%), 6 Fr (21 patients, 60%), and 7 Fr (1 patient, 2%). Technical success was achieved in 34 patients (97%), while ExoSeal malfunction occurred in 1 patient. There was no incidence of vessel occlusion, pseudoaneurysm, arteriovenous fistula, infection, and secondary bleeding. One patient developed a hematoma (>5 cm in size); however, it occurred before the use of ExoSeal due to side leakage from the inserted sheath. The ULSOSEAL technique was safe and feasible for hemostasis in patients who were considered unsuitable for the ExoSeal device.

Atrial Fibrillation is Associated with Femoropopliteal Totally Occlusive In-Stent Restenosis: A Single-Center, Retrospective, Observational Study.

INTRODUCTION: The proportion of patients with comorbid atrial fibrillation (AF) and peripheral artery disease (PAD) has increased in this era. This study aimed to assess the relationship between AF and totally occlusive in-stent restenosis (ISR) in femoropopliteal (FP) lesions. METHODS: In this study, 363 patients (461 stents) who underwent endovascular therapy with de novo stent implantation in our hospital between April 2007 and December 2016 were retrospectively evaluated. The patients were divided into two groups according to the AF status (AF group, 61 patients; sinus group, 302 patients). The primary endpoint was the incidence of totally occlusive ISR within 3 years. The secondary endpoint was the incidence of acute limb ischemia (ALI) due to FP stent occlusion. RESULTS: Baseline characteristics were similar, except for higher age and a lower prevalence of dyslipidemia in the AF group. The incidence of a totally occlusive ISR was higher in the AF group than in the sinus group (29.5% vs. 14.6%, p=0.004). A multiple Cox regression model suggested that presence of AF (hazard ratio, 2.10) and CTO lesion (hazard ratio, 1.97) which were the independent predictors of a totally occlusive ISR within 3 years. The incidence of ALI was significantly higher in the AF group than in the sinus group (3.9% vs. 0%, p=0.0001). In the AF group, the introduction of an anticoagulant did not prevent the occurrence of totally occlusive ISR (p=0.71) for ALI (p=0.79). CONCLUSIONS: AF is independently associated with totally occlusive ISR of FP stents; however, anticoagulant use does not prevent stent occlusion.

Impact of Dialysis Vintage and Renal Biomarkers on Mortality in Dialysis-Dependent Patients With Critical Limb Ischemia Undergoing Revascularization.

PURPOSE: Revascularization of both endovascular therapy (EVT) and surgical reconstruction improve clinical outcomes of patients with critical limb ischemia (CLI); however, treatment of dialysis-dependent patients with CLI is still challenging. This study aimed to investigate the impact of dialysis-related parameters on the risk of mortality in dialysis-dependent patients undergoing revascularization for CLI. MATERIALS AND METHODS: We retrospectively identified 274 dialysis-dependent patients with CLI (196 males; mean age 71 years), who underwent revascularization, from the clinical database of the surgical reconstruction vs peripheral intervention in patients with critical limb ischemia (SPINACH) study, which was a prospective, multicenter, observational study. Of these patients, 175 patients underwent EVT and 99 patients received surgical reconstruction. The current study evaluated the impact of dialysis vintage and renal biomarkers on the mortality rate of dialysis-dependent patients with CLI undergoing revascularization. RESULTS: During a mean follow-up period of 1.7 ± 1.1 years, 147 deaths were observed. The 3-year overall survival rate and its standard error were estimated to be 40.5% ± 8.1% using the Kaplan-Meier method. A Cox proportional hazard analysis revealed that dialysis vintage ≥4 years, serum creatinine levels <4.7 mg/dL, serum urea nitrogen ≥88 mg/dL, and calcium-phosphate product ≥62.6 mg2/dL2 were independent risk factors for mortality after adjustment for the detailed mortality risk score developed in the SPINACH study. Adding these parameters to the original mortality risk score slightly, but not significantly, increased the area under the time-dependent receiver operating characteristics curve from 0.74 (95% CI, 0.67 to 0.81) to 0.77 (0.71 to 0.84) (p=0.084), whereas continuous net reclassification improvement reached 0.75 (0.12 to 0.90) (p=0.027). CONCLUSION: We found that long dialysis vintage, low serum creatinine, high serum urea nitrogen, and high calcium-phosphate product were independently associated with the increased risk of mortality in dialysis-dependent patients with CLI undergoing revascularization.

Frequency, predictors, and effect of the slow-flow phenomenon after drug-coated balloon angioplasty for femoropopliteal lesions.

Drug-coated balloon (DCB) angioplasty for femoropopliteal (FP) lesions has been available in Japan since 2018. In daily practice, we encountered cases of the slow-flow phenomenon after DCB angioplasty. However, no data regarding the slow-flow phenomenon after DCB angioplasty for FP lesions are available. This study aimed to investigate the frequency, predictors, and effect of the slow-flow phenomenon following DCB angioplasty for FP lesions. This single-center, retrospective, observational study analyzed 88 FP lesions treated by DCB angioplasty between April 2018 and July 2019. Patients were divided into the slow-flow group (n = 7) and non-slow-flow group (n = 81) and were analyzed. The primary endpoint was primary patency at 6 months. The slow-flow phenomenon was observed in seven cases (8.0%). The slow-flow group had higher incidence rates of critical limb ischemia (CLI) (71% vs. 25%, p < 0.01), chronic total occlusion (CTO) lesions (86% vs. 26%, p < 0.01), and poor tibial vessel runoff (86% vs. 33%, p < 0.01) and had a longer DCB length (237 ± 56 mm vs. 159 ± 97 mm, p = 0.03) than the non-slow-flow group. The primary patency rate at 6 months was 71% in the slow-flow group and 91% in the non-slow-flow group (p = 0.09). The rate of freedom from target lesion revascularization at 6 months was 71% in the slow-flow group and 97% in the non-slow-flow group (p < 0.01). The amputation-free survival rate at 6 months was 71% and 95% (p = 0.02), whereas the survival rate at 6 months was 71% and 95% (p = 0.02). The incidence rate of the slow-flow phenomenon after DCB angioplasty for FP lesions was 8.0%. CLI, a CTO lesion, poor tibial vessel runoff, and total DCB length were associated with the slow-flow phenomenon. Our results indicate that the slow-flow phenomenon is associated with poor short-term clinical outcomes.

Usefulness of ultrasound-guided intraluminal approach for long occlusive femoropopliteal lesion.

To investigate the usefulness of ultrasound-guided (USG) intraluminal approach for femoropopliteal (FP) lesion. 64 patients (73 limbs) with de novo long occlusive (> 15 cm) FP lesions underwent USG intralumial approach from April 2012 to October 2016. Periprocedural intravascular ultrasound findings were collected. Clinical outcome and predictors of restenosis after USG intraluminal approach for de novo long occlusive FP lesion were investigated. Among the study participants, 34% were female, 50% had diabetes mellitus, and 10% received hemodialysis. Lesion and chronic total occlusion (CTO) lengths were 222 ± 55 mm and 201 ± 55 mm, respectively. Procedural success was achieved in 72 lesions (99%). Distal puncture was performed in 7 limbs (10%). The proportion of within-CTO intraplaque, subintimal, and medial routes were 87 ± 21%, 9 ± 15%, and 4 ± 11%, respectively. Primary patency was 71% and 69% at 1 and 2 years. Multivariate analysis revealed that within-CTO intraplaque route proportion [hazard ratio (HR) 0.81; 95% confidence interval (CI) 0.67-0.98, p = 0.0339] and lesion length (HR 1.11; CI 1.00-1.22; p = 0.0447) were independent predictors of restenosis.USG intraluminal approach facilitated acquisition of within-CTO intraplaque route in long occlusive FP lesions and could improve clinical outcome.