Risk and Prognosis of Upper Extremity Deep Vein Thrombosis.

Objectives: We aimed to investigate the clinical features of upper extremity deep vein thrombosis (UEDVT). Methods: We retrospectively reviewed the background, thrombus site, treatment, and outcome of 76 UEDVT patients. Results: Of the 76 UEDVT patients, 44 (57.9%) were men, and 51 (67.1%) were complicated by malignancy, 44 (57.9%) had an indwelling central vein (CV) catheter, 8 (10.5%) had concomitant pulmonary embolization (PE), and 33 (43.3%) were symptomatic. Regarding the thrombus site, the right internal jugular vein was the most common, with 30 cases (35.3%). As regards the treatment method, 53 patients (69.7%) received oral anticoagulants. In 2015, when direct oral anticoagulants (DOACs) was covered by insurance, there were 44 UEDVT cases, of which 34 (77.3%) received DOACs. Outcomes at a mean observation period of 37.5±41.5 months included 40 deaths (52.6%) with a mean survival of 16.3±21.3 months. The most common cause of death was malignancy, with 33 cases (82.5%). Conclusion: In the background of UEDVT, the combination of indwelling CV catheter placement and malignancy was frequently observed. While the risk of recurrence or PE complications is low, the prognosis of UEDVT complicated by malignancy is extremely poor.

Real-Time Assessment of Tissue Oxygen Saturation Using a Novel Oximeter During Revascularization for Acute Limb Ischemia: A Case Report.

Emergency surgery was performed to treat acute lower limb ischemia caused by heart thromboembolism and concomitant popliteal artery aneurysm. Using a near-infrared spectroscopy oximeter, regional tissue oxygen saturation (rSO2) was monitored to assess the tissue perfusion pre-, intra-, and postoperatively. rSO2 values did not increase sufficiently following thromboembolectomy of the superficial femoral artery, but they dramatically recovered after additional popliteal-anterior tibial bypass surgery. The affected limb was successfully salvaged. rSO2 monitoring was easily measured intraoperatively, which might be beneficial in evaluating tissue perfusion in patients with acute limb ischemia.

Pre-Operative Four Dimensional Flow Sensitive Magnetic Resonance Imaging Assessment of Aortic Side Branches as a Method to Predict Risk of Type II Endoleak Resulting in Sac Enlargement After EVAR.

OBJECTIVE: To predict sac enlargement with type II endoleak (ELII) before endovascular aneurysm repair (EVAR) using four dimensional flow sensitive magnetic resonance imaging (4D flow MRI). METHODS: A single centre retrospective analysis of prospectively collected data was conducted. Patients with an abdominal aortic aneurysm (AAA) who underwent EVAR between 2013 and 2019 were included. Aortic branches occluded pre-EVAR, and patients with endoleaks other than ELII were excluded. The aortic branch diameter, peak flow velocity (PFVe), and amplitude of the dynamics of flow volume (AFV) were measured in each aortic branch pre-EVAR. Total flow volume per minute (TFV/min), defined as the sum of AFV/min, was calculated in each case. According to computed tomography findings one year post-EVAR, the aortic branches and patients were divided into patent vessel and occluded vessel groups and sac expanding and non-expanding groups. PFVe, AFV/min, and TFV/min were analysed via receiver operating characteristic curve analysis. RESULTS: The patent aortic branches pre-EVAR (69 inferior mesenteric arteries [IMAs]; 249 lumbar arteries [LAs]) of 100 patients were included. Patent IMAs (n = 14) and occluded IMAs (n = 55), patent LAs (n = 23) and occluded LAs (n = 226), and expanding (n = 9) and non-expanding (n = 91) groups were compared, respectively. No statistically significant difference was observed in branch diameters (IMA; patent, 2.5 ± 0.8 mm, occluded, 2.5 ± 0.8 mm, p < .78 and LA; patent, 1.5 ± 0.3 mm, occluded, 1.5 ± 0.4 mm, p < .35). PFVe (IMA; patent, 262.6 mm2/sec, occluded, 183.4 mm2/sec and LA; patent, 142.6 mm2/sec, occluded, 47.7 mm2/sec) and AFV/min (IMA; patent, 8.4 mL, occluded, 5.2 mL and LA; patent, 4.2 mL, occluded, 1.4 mL) were higher in the patent vessel group (p < .050). TFV/min was statistically significantly higher in the expanding group (24.1 mL/min) than in the non-expanding group (7.0 mL/min) (p < .010). CONCLUSION: Pre-EVAR haemodynamic analyses using 4D flow MRI were useful to detect aortic branches responsible for ELII and to predict AAA cases with sac enlargement. This analysis suggests a new strategy for pre-EVAR aortic branch embolisation.

The Usefulness of a Three-Microneedle Device for Indocyanine Green Fluorescence Lymphography.

Background: Indocyanine green (ICG) fluorescence lymphography is widely used to diagnose lymphedema. There is little consensus on the appropriate injection method for ICG fluorescence lymphangiography. We used a three-microneedle device (TMD) for skin injection of ICG solution and investigated its usefulness. Methods and Results: Thirty healthy volunteers were injected with ICG solution using a 27-gauge (27G) needle in one foot and a TMD in the other foot. Injection-related pain was evaluated using the Numerical Rating Scale (NRS) and Face Rating Scale (FRS). The skin depth of the injected ICG solution was evaluated by injecting the solution into the skin of amputated lower limbs using a 27G needle or TMD using ICG fluorescence microscopy. The median and interquartile range of the NRS scores was 3 (3-4) and 2 (2-4) in the 27G needle and TMD groups, respectively; that of the FRS scores was 2 (2-3) and 2 (1-2) in the 27G needle and TMD groups, respectively. Injection-related pain was significantly lower with the TMD than with the 27G needle. The lymphatic vessels were similarly visible using both needles. The depth of the ICG solution varied for each injection with a 27G needle (400-1200 µm) and was consistent at ∼300-700 µm below the skin surface using the TMD. Injection depth was significantly different between the 27G needle and the TMD. Conclusions: Injection-related pain decreased using the TMD, and ICG solution depth was consistent on fluorescence lymphography. A TMD may be useful for ICG fluorescence lymphography. Clinical Trials Registry (UMIN-CTR; ID: UMIN000033425).

Survey of Food Intake in Patients with Abdominal Aortic Aneurysm.

Abdominal aortic aneurysm (AAA) is a vascular disease that involves asymptomatic progressive expansion of the abdominal aorta. Aneurysm rupture is associated with a high mortality rate. Dietary conditions may be associated with the development and rupture of AAA. However, the relationship between nutrition and AAA is not completely understood. In this study, a nutrition survey was conducted using a brief self-administered diet history questionnaire (BDHQ) to evaluate the relationship between AAA and dietary habits. One-hundred and twenty-six Japanese people participated in the nutrition survey. Food intake status was analyzed in four groups: the analyzed group-1 (all men), analyzed group-2 (men with smoking history), analyzed group-3 (all women) and analyzed group-4 (women without smoking history). In group-2 and group-3, the intake of citrus fruits was significantly lower in the AAA group than in the non-AAA group. In group-2, the intake of soybean and soybean products was significantly lower in the AAA group than in the non-AAA group. In analyzed group-3, the intake of other vegetables (vegetables except for green and yellow vegetables and soybeans) and seafood was significantly lower in the AAA group than in the non-AAA group. This study suggests that AAA onset may be associated with low intake of fruits, soybeans, vegetables, and seafood.

Effects of inhaled ß­caryophyllene on vascular stiffness in smokers: A randomized, double­blind, placebo­controlled trial.

Approximately 1.14 billion smokers worldwide are at risk of developing tumors, cardiovascular diseases and respiratory diseases. Smoking cessation is the first choice of health care; however, the disease should be attenuated in individuals who never stop smoking, which escalates medical costs. Therefore, alternative options are needed to manage the social burden. The present study proposed an alternative method to prevent such diseases by inhalation of ß-caryophyllene (BCP). A placebo-targeted, dose-searching, double-blind, parallel-group comparative study was conducted on 19 subjects. The BCP intervention was performed using a flavor capsule inserted in a cigarette filter. The primary endpoint was the reducibility of brachial-ankle pulse wave velocity (baPWV). The secondary endpoints were confirmation of the bioavailability of BCP inhalation with cigarette smoke, confirmation of the effect of BCP inhalation on respiratory function, and association between respiratory function and blood concentration and baPWV reduction. The BCP concentration in the blood reached 4 ng/ml in the BCP 15% group 10 min after inhalation. The baPWV decreased in BCP-inhaling subjects whose initial baPWV was >1,300 cm/sec. The correlation analyses revealed that the higher the forced expiratory volume in 1 sec, the better the transition of baPWV. Inhaled BCP with cigarette smoke could reduce the baPWV and the risk of cardiovascular diseases in smokers. These findings indicated that with the introduction of BCP capsule-cigarettes in the future, smokers will be able to take care of their health, which may help reduce national medical costs. BCP microcapsules placed in cigarette wrapping paper may possibly reduce the risk of sidestream smoke and contribute to improved public health. This clinical research was retrospectively registered in the University Hospital Medical Information Network (UMIN)-Clinical Trials Registry with the following identifications: UMIN000048510 and UMIN000048512 on August 15, 2022.

Characteristics and Prognostic Factors of Venous Thromboembolism in Cancer Patients.

Background: Improving the prognosis of patients with malignant tumors is increasing the number of patients who develop venous thromboembolism. We examined the characteristics and prognostic factors of VTE patients with cancer. Methods: We diagnosed 725 VTE patients from April 2005 to March 2018. There were 322 cancer associated patients (CAT) and 403 non-cancer associated patients (nonCAT). We examined characteristics and prognostic factors of VTE in CAT patients. Results: There were 156 women and 166 men in CAT, and 132 women and 271 men in nonCAT. There was no significant difference in the location of proximal portion of thrombus. When locations were divided into left leg, right leg, and bilateral legs, bilateral cases were more common in CAT group. Comparing the overall survival after VTE diagnosis in the CAT group, the prognosis was poor in patients with high D-dimer level (≧6 µg/mL) along with cancer metastasis and recurrence. Conclusions: Various VTE factors predict prognosis in CAT patients, and CAT is important in the treatment of cancer patients. (This is secondary publication from Jpn J Phlebol 2020; 31(3): 153-159.).

The Patency of Tibial/Peroneal Arteries Affects the Increment of Regional Tissue Saturation of Oxygen in Each Angiosome after Superficial Femoral Artery Revascularization.

Objective: The angiosome model is a controversial concept in the revascularization of patients with chronic limb-threatening ischemia (CLTI). The aim of this study was to demonstrate the importance of patency of the tibial/peroneal arteries for regional tissue oxygenation in each angiosome during endovascular therapy (EVT) of the superficial femoral artery (SFA). Materials and Methods: We devised a novel near-infrared spectroscopy oximeter, "TOE-20," for real-time monitoring of regional tissue oxygen saturation (rSO2). Using TOE-20, we prospectively assessed rSO2 at each angiosome in 23 CLTI patients who underwent successful revascularization of the SFA. During EVT, three sensor probes were placed at the dorsal foot, plantar foot, and outer ankle for rSO2 monitoring. Results: At the end of EVT, rSO2 at all angiosomes was significantly elevated by SFA revascularization. The change in rSO2 in each angiosome was larger in patients with patent relevant arteries than in those with occluded relevant arteries (i.e., anterior tibial artery patency, posterior tibial artery patency, and peroneal artery patency). Conclusion: The patency of the tibial/peroneal arteries is important for regional tissue oxygenation in EVT. Using TOE-20 and rSO2-based revascularization, it may possible to anticipate whether an ischemic ulcer will heal or not.

Real-time assessment of tissue oxygen saturation during endovascular therapy for chronic limb threatening ischemia using a novel oximeter.

In the present study, we have introduced a novel real-time, near-infrared spectroscopy oximeter, the TOE-20 (Astem, Co, Ltd, Kawasaki, Japan), which can simultaneously measure the regional tissue oxygen saturation (rSO2) in the skin and subcutaneous tissue at three angiosomes of the foot. Seven patients with chronic limb threatening ischemia who had undergone successful revascularization of the superficial femoral artery were included. The analysis revealed a significant correlation between the rSO2 and skin perfusion pressure. After revascularization, the rSO2 and skin perfusion pressure had both increased at the three regions, although the increase at the plantar foot was insignificant. These results indicate that the TOE-20 can be successfully used to monitor the rSO2 during endovascular treatment.

Role of Subcutaneous Adipose Tissues in the Pathophysiology of Secondary Lymphedema.

Background: Secondary lymphedema (LE) occurs due to the disruption of lymphatic circulation. Lymphatic fluid accumulation in subcutaneous tissues induces adipocyte proliferation. Obesity is an important risk factor for the occurrence and deterioration of LE. Although the relationship between LE and subcutaneous adipose tissue increase has been reported clinically, their pathophysiological relationship remains unknown. Thus, we aimed to verify whether subcutaneous adipose tissue increase is involved in the pathophysiology of secondary LE. Methods and Results: The hindlimb model of secondary LE was created using male Sprague-Dawley rats (control and LE groups; n = 5 each). Skin samples were obtained on postoperative day 168. Histological examination and quantitative real-time polymerase chain reaction analysis of inflammatory adipokines, tumor necrosis factor-alpha (Tnf-α), C-C chemokine ligand 2 (Ccl2), and interleukin-6 (Il-6) were performed. Limb volume and subcutaneous adipose tissues significantly increased in the LE group compared with those in the control. Macrophages aggregated in the augmented adipose tissues, around the adipocytes, and formed crown-like structures (CLSs). The number of CLSs significantly increased in the LE group. These macrophages expressed transforming growth factor-beta 1 (TGF-ß1). Inflammatory adipokine secretion was not observed. Although Il-6 expression increased in the LE group, IL-6 was expressed in subcutaneous myofibroblasts but not in subcutaneous adipocytes. Conclusion: As TGF-ß1 derived from subcutaneous myofibroblasts is involved in skin fibrosis during LE, TGF-ß1 derived from adipose tissues may also play a similar role. Drug treatment for subcutaneous adipose tissue reduction may improve the skin condition in secondary LE and may be a new therapeutic strategy.

Differences in Vasa Vasorum Distribution in Human Aortic Aneurysms and Atheromas.

The pathophysiological difference between aortic atheromas and aneurysms is unknown. We focused on the vasa vasorum (VV), which play a critical role in maintaining aortic homeostasis and are also involved in vascular diseases. We investigated the differences in VV between the atheromas and aneurysms. Human abdominal aortic samples were obtained from patients with abdominal aortic aneurysm during surgery or autopsy cases. Autopsy cases were divided into 2 groups according to atheromas. The VV were evaluated using immunohistochemical staining for von Willebrand factor. Intimal VV increased in both the atheroma and aneurysm groups, medial VV increased, and adventitial VV decreased only in the aneurysm group. We also observed that the medial VV were connected to the adventitial VV in the atheroma group and to intimal VV in the aneurysm group. We suggest the outside-in VV or inside-out VV theories. Atheroma induces hypoxia of aortic walls, and angiogenic factors might induce an increase of intimal VV derived from adventitial VV (outside-in VV). However, adventitial VV decrease induces hypoxia of aortic walls, and angiogenic factors might induce an increase of intimal VV derived from aortic lumen (inside-out VV). These differences of VV may contribute in elucidating the pathophysiology of aortic diseases.

A phase III, multicenter, single-arm study to assess the utility of indocyanine green fluorescent lymphography in the treatment of secondary lymphedema.

OBJECTIVE: Indocyanine green (ICG) fluorescent lymphography might be useful for assessing patients undergoing lymphatic surgery for secondary lymphedema. The present clinical trial aimed to confirm whether ICG fluorescent lymphography would be useful in evaluating lymphedema, identifying lymphatic vessels suitable for anastomosis, and confirming patency of lymphaticovenular anastomosis in patients with secondary lymphedema. METHODS: The present phase III, multicenter, single-arm, open-label, clinical trial (HAMAMATSU-ICG study) investigated the accuracy of lymphedema diagnosis via ICG fluorescent lymphography compared with lymphoscintigraphy, rate of identification of lymphatic vessels at the incision site, and efficacy for confirming patency of lymphaticovenular anastomosis. The external diameter of the identified lymphatic vessels and the distance from the skin surface to the lymphatic vessels using preoperative ICG fluorescent lymphography were measured intraoperatively under surgical microscopy. RESULTS: When the clinical decision for surgery at each research site was made, the standard diagnosis of lymphedema was considered correct. For the 26 upper extremities, a central judgment committee who was unaware of the clinical presentation confirmed the imaging diagnosis was accurate for 100.0% of cases, whether the assessments had been performed via lymphoscintigraphy or ICG lymphography. In contrast, for the 88 lower extremities, the accuracy of the diagnosis compared with the diagnosis by the central judgment committee was 70.5% and 88.2% for lymphoscintigraphy and ICG lymphography, respectively. The external diameter of the identified lymphatic vessels was significantly greater in the lower extremities than in the upper extremities (0.54 ± 0.21 mm vs 0.42 ± 0.14 mm; P < .0001). Also, the distance from the skin surface to the lymphatic vessels was significantly longer in the lower extremities than in the upper extremities (5.8 ± 3.5 mm vs 4.4 ± 2.6 mm; P = .01). For 263 skin incisions, with the site placement determined using ICG fluorescent lymphography, the rate of identification of lymphatics vessels suitable for anastomosis was 97.7% (95% confidence interval, 95.1%-99.2%). A total of 267 lymphaticovenular anastomoses were performed. ICG fluorescent lymphography was judged as "useful" for confirming patency after the anastomosis in 95.1% of the cases. CONCLUSIONS: ICG fluorescent lymphography could be useful for improving the treatment of patients with secondary lymphedema from the outpatient setting to surgery.

Tissue Oximeter with Selectable Measurement Depth Using Spatially Resolved Near-Infrared Spectroscopy.

Tissue oxygenation sensing at a few millimeters deep is useful for surgical and postoperative management. However, the measurement sensitivity at each depth and the proper sensor combination have not been clarified. Here, the measurement characteristics of oximetry by spatially resolved near-infrared spectroscopy were analyzed using Monte Carlo simulation and phantom experiment. From summing the sensitivities of each depth, it was quantitatively found that the measurement sensitivity curve had a peak, and the measurement depth can be adjusted by combining the two distances between the light source and the detector. Furthermore, the gastric tissue was 10-20% smaller in terms of measurement depth than the skin-subcutaneous tissue. A miniaturized oximeter was prototyped so that it could be used in combination with an endoscope or laparoscope. The optical probes consisted of light emitting diodes with wavelengths of 770 nm and 830 nm and photodetectors located 3 to 30 mm from the light source. Phantom experiments using the probes demonstrated the tendency of theoretical analysis. These results suggest the possibility of measuring tissue oxygen saturation with a selectable measurement depth. This selectable method will be useful for obtaining oxygenation information at a depth of 2-5 mm, which is difficult to measure using only laparoscopic surface imaging.

Recombinant Interleukin-19 Suppresses the Formation and Progression of Experimental Abdominal Aortic Aneurysms.

Background Interleukin-19 is an immunosuppressive cytokine produced by immune and nonimmune cells, but its role in abdominal aortic aneurysm (AAA) pathogenesis is not known. This study aimed to investigate interleukin-19 expression in, and influences on, the formation and progression of experimental AAAs. Methods and Results Human specimens were obtained at aneurysm repair surgery or from transplant donors. Experimental AAAs were created in 10- to 12-week-old male mice via intra-aortic elastase infusion. Influence and potential mechanisms of interleukin-19 treatment on AAAs were assessed via ultrasonography, histopathology, flow cytometry, and gene expression profiling. Immunohistochemistry revealed augmented interleukin-19 expression in both human and experimental AAAs. In mice, interleukin-19 treatment before AAA initiation via elastase infusion suppressed aneurysm formation and progression, with attenuation of medial elastin degradation, smooth-muscle depletion, leukocyte infiltration, neoangiogenesis, and matrix metalloproteinase 2 and 9 expression. Initiation of interleukin-19 treatment after AAA creation limited further aneurysmal degeneration. In additional experiments, interleukin-19 treatment inhibited murine macrophage recruitment following intraperitoneal thioglycolate injection. In classically or alternatively activated macrophages in vitro, interleukin-19 downregulated mRNA expression of inducible nitric oxide synthase, chemokine C-C motif ligand 2, and metalloproteinases 2 and 9 without apparent effect on cytokine-expressing helper or cytotoxic T-cell differentiation, nor regulatory T cellularity, in the aneurysmal aorta or spleen of interleukin-19-treated mice. Interleukin-19 also suppressed AAAs created via angiotensin II infusion in hyperlipidemic mice. Conclusions Based on human evidence and experimental modeling observations, interleukin-19 may influence the development and progression of AAAs.

A Pilot Study Investigating the Use of Regional Oxygen Saturation as a Predictor of Ischemic Wound Healing Outcome after Endovascular Treatment in Patients with Chronic Limb-Threatening Ischemia.

Objective: To determine the prognostic value of regional tissue oxygenation saturation (rSO2) for ulcer healing after endovascular treatment (EVT) of peripheral arterial disease (PAD). Materials and Methods: Among PAD patients, 34 patients with chronic limb-threatening ischemia underwent EVT for limb salvage. We retrospectively analyzed the cutoff rSO2 values on postoperative day 1 to predict ulcer healing and patient prognosis. Skin perfusion pressure (SPP) and transcutaneous oxygen pressure (TcPO2) were also used to assess wound healing. Results: A finger-mounted tissue oximeter can easily measure rSO2 on the dorsal foot. Among the 34 patients, the ulcer healed in 25, and no changes were observed in 2 patients at 1 month after EVT. However, 7 patients needed major amputation at the same time. Wound healing was achieved in all patients with rSO2≥50%. With this cutoff, the sensitivity and specificity of the new device for wound healing were 100% and 64%, respectively. In all the wound healing cases, SPP was ≥45 mmHg, and TcPO2 was ≥40 mmHg. Conclusion: To assess limb ischemia, rSO2 can be measured quickly and easily using this device. We suggest that an rSO2>50% shows good prognosis for ulcer healing.

Usefulness of a finger-mounted tissue oximeter with near-infrared spectroscopy for evaluating the intestinal oxygenation and viability in rats.

PURPOSE: To investigate the utility of the device for evaluating intestinal oxygenation and viability using an animal model. METHODS: Sprague-Dawley rats underwent laparotomy under general anesthesia, and the blood vessels in the terminal ileum were clamped to create ischemia. We measured the regional tissue oxygenation saturation (rSO2) using an oximeter after 1, 3, and 6 h of vessel clamping. Ischemic tissue damage was assessed using a histological score. The intestine was reperfused after each clamping period, and intestinal rSO2 and survival rate were evaluated. RESULTS: When reperfusion was performed at 1 and 3 h after ischemia, rSO2 increased after 10 min, and it improved to the same level as for normal intestine after 1 h; all rats survived for 1 week. In contrast, after 6 h of ischemia, rSO2 did not increase after reperfusion, and all animals died within 2 days. The histological scores increased after 1 h of reperfusion, with longer clamping periods. CONCLUSION: A finger-mounted tissue oximeter could evaluate intestinal ischemia and the viability, which is thus considered to be a promising result for future clinical application.

Fibrinolysis-resistant carbonylated fibrin detected in thrombi attached to the vascular wall of abdominal aortic aneurysms.

In this study, we investigated how carbonylation of fibrinogen by acrolein modified its indispensable function to enhance fibrinolysis after being converted to fibrin and contributed to generating a fibrinolysis-resistant fibrin clot. Acrolein-treated fibrinogen was subjected to tissue plasminogen activator-induced fibrinolysis assay and the effect of lysine residue carbonylation in fibrinogen on fibrinolysis was analyzed. The acrolein-treated fibrinogen-derived fibrin clot appeared more resistant to fibrinolysis and the N-acetyl 3-formyl-3,4-dehydropiperidino (FDP)-Lysine levels in the lysed solution were positively correlated with the duration of clot lysis. The lysine analog 6-amino hexanoic acid (6AHA), which mimics the C-terminal lysine of fibrin, was carbonylated and its enhancing effect on Glu1-plasminogen activation was evaluated. After incubation with acrolein, 6AHA was converted to N-acetyl FDP-6AHA, losing its ability to enhance Glu1-plasminogen activation. These results suggest that fibrinogen carbonylation by acrolein to generate N-acetyl FDP-Lysine resulted in the generation of fibrinolysis-resistant fibrin by attenuating the C-terminal lysine-dependent activation of the Glu1-plasminogen. In abdominal aortic aneurysms, fibrin(ogen) containing the acrolein adduct N-acetyl FDP-Lysine was detected in the vascular wall-attached thrombi. These results suggest that this mechanism is likely involved in the modification of fibrinolysis-resistant thrombi and to their persistence for a long period.

Abnormal Flow Dynamics Result in Low Wall Shear Stress and High Oscillatory Shear Index in Abdominal Aortic Dilatation: Initial in vivo Assessment with 4D-flow MRI.

PURPOSE: To characterize the non-laminar flow dynamics and resultant decreased wall shear stress (WSS) and high oscillatory shear index (OSI) of the infrarenal abdominal aortic dilatation, cardiac phase-resolved 3D phase-contrast MRI (4D-flow MRI) was performed. METHODS: The prospective single-arm study was approved by the Institutional Review Board and included 18 subjects (median 67.5 years) with the dilated infrarenal aorta (median diameter 35 mm). 4D-flow MRI was conducted on a 1.5T MRI system. On 3D streamline images, laminar and non-laminar (i.e., vortex or helical) flow patterns were visually assessed both for the dilated aorta and for the undilated upstream aorta. Cardiac phase-resolved flow velocities, WSS and OSI, were also measured for the dilated aorta and the upstream undilated aorta. RESULTS: Non-laminar flow represented by vortex or helical flow was more frequent and overt in the dilated aorta than in the undilated upstream aorta (P < 0.0156) with a very good interobserver agreement (weighted kappa: 0.82-1.0). The WSS was lower, and the OSI was higher on the dilated aortic wall compared with the proximal undilated segments. In mid-systole, mean spatially-averaged WSS was 0.20 ± 0.016 Pa for the dilated aorta vs. 0.68 ± 0.071 Pa for undilated upstream aorta (P < 0.0001), and OSI on the dilated aortic wall was 0.093 ± 0.010 vs. 0.041 ± 0.0089 (P = 0.013). The maximum values and the amplitudes of the WSS at the dilated aorta were inversely proportional to the ratio of dilated/undilated aortic diameter (r = -0.694, P = 0.0014). CONCLUSION: 4D-flow can characterize abnormal non-laminar flow dynamics within the dilated aorta in vivo. The wall of the infrarenal aortic dilatation is continuously and increasingly affected by atherogenic stimuli due to the flow disturbances represented by vortex or helical flow, which is reflected by lower WSS and higher OSI.

HAMAMATSU-ICG study: Protocol for a phase III, multicentre, single-arm study to assess the usefulness of indocyanine green fluorescent lymphography in assessing secondary lymphoedema.

INTRODUCTION: Secondary lymphoedema of the extremities is an important quality-of-life issue for patients who were treated for their malignancies. Indocyanine green (ICG) fluorescent lymphography may be helpful for assessing lymphoedema and for planning lymphaticovenular anastomosis (LVA). The objective of the present clinical trial is to confirm whether or not ICG fluorescent lymphography using the near-infrared monitoring camera is useful for assessing the indication for LVA, for the identification of the lymphatic vessels before the conduct of LVA, and for the confirmation of the patency of the anastomosis site during surgery. METHODS AND ANALYSIS: This trial is a phase III, multicentre, single-arm, open-label clinical trial to assess the efficacy and safety of ICG fluorescent lymphography when assessing and treating lymphoedema of patients with secondary lymphoedema who are under consideration for LVA. The primary endpoint is the identification rate of the lymphatic vessels at the incision site based on ICG fluorescent lymphograms obtained before surgery. The secondary endpoints are 1) the sensitivity and specificity of dermal back flow determined by ICG fluorescent lymphography as compared with 99mTc lymphoscintigraphy-one of the standard diagnostic methods and 2) the usefulness of ICG fluorescent lymphography when confirming the patency of the anastomosis site after LVA. ETHICS AND DISSEMINATION: The protocol for the study was approved by the Institutional Review Board of each institution. The trial was filed for and registered at the Pharmaceuticals and Medical Devices Agency in Japan. The trial is currently on-going and is scheduled to end in June 2020. TRIAL REGISTRATION NUMBER: jRCT2031190064; Pre-results.

Target region oxygenation-based endovascular treatment in a chronic limb-threatening ischemia patient with multifocal arterial diseases.

Patients with chronic limb-threatening ischemia often have multiple segmental diseases requiring revascularization. However, there is no defined milestone to indicate sufficient endovascular treatment (EVT). Using multiple near-infrared spectroscopic oximeters, we intraoperatively monitored regional tissue oxygen saturation (rSO2) to perform target region oxygenation-based EVT for a patient with chronic limb-threatening ischemia. Stent placement at the superficial femoral artery and angioplasty of the tibioperoneal trunk enabled rSO2 in the target ischemic regions (dorsal foot and heel) to be >50% for ulcer healing. We herein describe target region oxygenation-based EVT with rSO2 monitoring as an effective strategy for performing the minimum requisite procedures.