An aneurysm sac enlargement caused by type II endoleak (T2EL) following endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms may cause serious complications such as rupture. Consequently, methods that preoperatively prevent or postoperatively treat T2EL have been employed. When significant aneurysm enlargement occurs due to persistent T2EL, embolization is first performed through several access points. However, although these endovascular reinterventions have a high technical success rate and are safe, their effectiveness remains questionable. When such endovascular procedures fail to stabilize sac enlargement, open surgical conversion (OSC) becomes the last-resort treatment option. We review several strategies of OSC for the repair of T2EL following EVAR. Among the three main OSC procedures, namely, complete endograft removal, partial endograft removal, and complete endograft preservation, partial endograft removal under infrarenal clamping was considered the most appropriate owing to its less invasiveness and durability.

Takayasu’s arteritis, first described by Dr. Mikito Takayasu in 1908, is a systemic vasculitis that mostly affects the aorta and its major branches. Although the etiology of the disease is yet unknown, genetic and environmental factors may both play a role. One hundred years after the discovery of Takayasu’s arteritis, inflammation is finally widely recognized as a fundamental condition common to all vascular diseases, and clinical trials have proven the efficacy of molecularly targeted drugs that block each step of the NLRP3 inflammasome/interleukin (IL)-1β/IL-6 cascade in patients with atherosclerotic vascular disease and elevated C-reactive protein (CRP). Recent advances have also been made in the treatment of Takayasu’s arteritis. The randomized controlled trials and subsequent open-label and post-marketing surveillance studies in Japan have demonstrated that tocilizumab, an anti-IL-6 receptor antibody, is effective in the treatment of Takayasu’s arteritis and prevents relapse during tapering of prednisolone doses. IL-6 is also heavily engaged in the remodeling of large vessels after acute aortic dissection as demonstrated in animal studies. In patients with acute aortic dissection, those with markedly elevated CRP levels in the acute phase are known to have an increased risk of aorta-related events, such as rupture due to aortic diameter enlargement, in the subacute and chronic phases. We discovered that elevated CRP levels following aortic dissection are caused by IL-6, which is produced by neutrophils that infiltrate the adventitia of the dissected aorta. In a mouse model of acute aortic dissection, we showed that IL-6 produced by these neutrophils causes progressive destruction of the arterial wall structure and that blockade of IL-6 signaling can prevent post-dissection vascular remodeling and improve life outcome. Therefore, inhibiting IL-6 signaling is anticipated to be effective in the secondary prevention of myocardial infarction and suppression of vascular modeling after dissection and even as an anti-inflammatory therapy for Takayasu’s arteritis; however, this approach does not solve everything. Undoubtedly, the mechanisms of inflammation in vascular disease are diverse and complex, and the cytokines and cell populations involved at each site (coronary artery vs. aorta) and in each phenotype (atherosclerosis vs. aortic aneurysm vs. aortic dissection) need to be understood for each type of inflammation. Osteopontin (OPN) is a recruiter of monocytes and macrophages, induces cellular immune responses as a Th1 cytokine, acts as a fibrosis-promoting factor, and has been shown to be deeply involved in the pathogenesis of vascular diseases. We have shown that senescent T cells, which emerge with obesity and aging, secrete significant amounts of OPN, leading to metabolic abnormalities and chronic inflammation. Neutrophil extracellular traps (NETs) released from activated neutrophils have been shown to contribute to the pathogenesis of acute coronary syndromes (ACS) by interacting with macrophages, platelets, and vascular endothelial cells and thus promoting plaque erosion and immunothrombosis. In addition to standard anticoagulant and antiplatelet therapies, the effectiveness of anti-immunothrombotic therapies targeting NETs as a new preventive and therapeutic approach for ACS will be examined in the future.

Objective: Elastic compression stockings are used to prevent venous thrombosis in postsurgical patients. However, they have been associated with skin complications, such as medical device-related pressure ulcers. This study aimed to assess the effect of elastic compression stockings on the skin tissue status of the lower limbs.

Methods: Transcutaneous oxygen pressure (TcPO₂) was measured in the anterior tibia and corresponding soft skin of healthy subjects before, during, and after continuous use of elastic stockings for 30 min.

Results: Wearing elastic stockings significantly reduced TcPO₂ in the skin of the anterior tibia, and removal of the stockings restored TcPO₂ values. Both individuals who exercised regularly and men had lower TcPO₂ at all measurement points than both individuals who did not exercise and women. Older subjects (50–60 years) had reduced TcPO₂ in the sural region than younger ones (20–30 years).

Conclusion: The use of elastic compression stockings caused an early decrease of TcPO₂ in healthy subjects. Clinical patients were predicted to be at a high risk of wounding.

Objective: Acute pulmonary embolism (PE) is potentially fatal. Age, sex, chronic comorbidities, vital signs, and echocardiographic findings are well-known predictive indicators of the short-term mortality. However, the impact of concurrent acute illness on the prognosis is unclear.

Materials and Methods: This is a retrospective cohort study using data of hospitalized patients with a diagnosis of acute PE without hemodynamic instability. The outcome measure was 30-day all-cause mortality after diagnosis of acute PE.

Results: A total of 130 patients were analyzed (68.5±15.5 years old, 62.3% female). Eight patients (6.2%) had concurrent acute illness. The proportion of the simplified pulmonary embolism severity index (sPESI)≥1, and positive findings of right ventricular overload were similar between the two groups. Six patients (4.9%) without concurrent acute illness died; whereas, three patients (37.5%) with concurrent acute illness died (p=0.011). Concurrent acute illness was associated with 30-day all-cause mortality in the univariate logistic model (odds ratio: 11.6, 95% confidence interval; 2.2–60.4; p=0.008).

Conclusion: In patients with hemodynamically stable acute PE, short-term prognosis was significantly worse in patients with concurrent acute illness than those without concurrent acute illness.

Objectives: The relationship between the thrombotic event and prognosis in patients with coronavirus disease 2019 (COVID-19) has not yet been fully investigated in Japan. Our study aimed to investigate the clinical outcomes and risk factors for thrombosis in hospitalized patients with COVID-19 in Japan.

Materials and Methods: We compared the patient characteristics and clinical outcomes among patients with thrombosis (N=55) and those without thrombosis (N=2839) by using a large-scale data of CLOT-COVID study (thrombosis and antiCoaguLatiOn Therapy in patients with COVID-19 in Japan Study: UMIN000045800). Thrombosis included venous thromboembolism, ischemic stroke, myocardial infarction, and systemic arterial thromboembolism.

Results: Higher rates of mortality and bleeding events were shown in hospitalized patients with COVID-19 with thrombosis compared to those without thrombosis (all-cause mortality, 23.6% vs. 5.1%, P<0.001; major bleeding, 23.6% vs. 1.6%, P<0.001). Multivariable analysis revealed that the independent risk factors of thrombosis were male sex, D-dimer level on admission>1.0 µg/mL, and moderate and severe COVID-19 status on admission.

Conclusions: The development of thrombosis in hospitalized patients with COVID-19 was related to higher mortality and major bleeding, and several independent risk factors for thrombosis could help determine the patient-appropriate treatment for COVID-19.

Background: Drug-coated balloons (DCBs) and drug-eluting stents (DES) were available for treating femoropopliteal disease since 2017 and 2019. However, there are few reports to investigate whether approval of DCB and DES improved primary patency in clinical practice.

Materials and Methods: We divided consecutive 407 patients into 2017 (n=93), 2018 (n=128), and 2019 (n=186) groups, undergoing endovascular therapy (EVT) for de novo femoropopliteal lesions in our hospital. We retrospectively compared clinical characteristics, procedure, and one-year patency between the three groups.

Results: Baseline characteristics were not different except for the lower rate of popliteal lesions in 2017 (p=0.030). Use of DCB increased from 7.5% in 2017 to 38.7% in 2019, and use of DES from 0.0% in 2018 to 24.2% in 2019. One-year primary patency increased significantly both from 2017 to 2018 (62.7% vs. 70.8%, p=0.036) and from 2018 to 2019 (70.8% vs. 80.5%, p=0.025). Cox proportional multivariate analysis revealed that restenosis was independently associated with advanced age (p=0.036) and hemodialysis (p=0.003). Conversely, use of paclitaxel-based devices (p<0.001) and larger diameter of finalized devices (p=0.005) were protective factors against restenosis.

Conclusion: One-year primary patency after EVT in femoropopliteal lesions was improved annually by utilizing DCB and DES, individually.

Objective: We aimed to evaluate the visual measurements of coronary artery calcium (CAC) on nonelectrocardiogram (ECG)-gated chest computed tomography (CT) using a simple scoring method that involves counting the number of CT slices containing CAC.

Materials and Methods: We analyzed 163 participants who underwent both coronary and chest CT examinations at six centers within 3 months. Agatston scores were calculated on standard ECG-gated scans and classified as none (0), mild (1–99), moderate (100–400), or severe (>400). Next, chest CT images were reconstructed to standard 5.0 mm axial slices. Then, CAC on chest CT scans was measured using two methods: the Weston score (sum of the assigned score of each vessel, range: 0–12) and number of slices showing CAC (Ca-slice#).

Results: When the Weston score and Ca-slice# were divided into four levels according to the optimal divisional levels corresponding to the Agatston score classes, good agreements with the 4-grade Agatston score were observed (kappa value=0.610 and 0.794, respectively). The sensitivity and specificity of Ca-slice# ≥9 to identify severe Agatston scores of >400 were 86% and 96%, respectively.

Conclusion: The Ca-slice#, a simple scoring method using chest CT scans, was in good agreement with the ECG-gated Agatston score.

Objective: On April 16, 2016, earthquakes struck Kumamoto. In this report, the incidence and treatment of venous thromboembolism (VTE) in patients presenting to our hospital are summarized.

Materials and Methods: We reviewed the details of 22 consecutive patients who were diagnosed with VTE at our hospital during the 2 weeks after the earthquakes.

Results: Nineteen of the 22 patients stayed in their cars overnight after the earthquakes. Particularly, during the first 4 days, seven consecutive patients were hospitalized for pulmonary thromboembolism. All seven patients had sheltered in their cars after the earthquakes. The two patients transported on days 2.42 and 3.54 were the most severe cases. One patient was admitted after emergency initiation of venoarterial extracorporeal membrane oxygenation for treatment of hemodynamic collapse, whereas the other patient was admitted after resuscitation. By contrast, deep vein thrombosis (DVT) alone occurred within 5–9 days of the earthquakes. Bilateral DVT was the most common, which was followed by DVT on the right side only.

Conclusion: The incidence of VTE might be higher after an earthquake, and an overnight stay in a car might be a risk factor for VTE. Stable patients based on the D-dimer concentration can be managed with nonwarfarin oral anticoagulants.

Objectives: To assess the external validity of the Padua and International Medical Prevention Registry on Venous Thromboembolism (IMPROVE-VTE) risk assessment models (RAMs) for predicting venous thromboembolism (VTE) within 90 days of admission among hospitalized medical patients in Japan.

Materials and Methods: A university hospital cohort comprising 3876 consecutive patients ages ≥15 years admitted to a general internal medicine department between July 2016 and July 2021 was retrospectively analyzed using data extracted from their medical records.

Results: A total of 74 VTE events (1.9%), including six cases with pulmonary embolism (0.2%), were observed. Both RAMs had poor discriminative performance (C-index=0.64 for both) and generally underestimated VTE risks. However, recalibrating the IMPROVE-VTE RAM to update the baseline hazard improved the calibration (calibration slope=1.01). Decision curve analysis showed that a management strategy with no prediction model outperformed a clinical management strategy guided by the originally proposed RAMs.

Conclusions: Both RAMs require an update to function in this particular setting. Further studies with a larger-sized cohort, including re-estimation of the individual regression coefficients with additional, more context-specific predictors, are needed to create a useful model that would help advance risk-oriented VTE prevention programs.

Isolated aneurysms of the external iliac artery are rare in patients with fibromuscular dysplasia. In this study, we report the case of a 74-year-old man with advanced gastric cancer who was found to have a medium-sized aneurysm of the external iliac artery (35 mm) on preoperative computed tomography angiograms. The patient underwent laparoscopic gastrectomy followed by replacement of the external iliac artery 6 months later. Histological examination of biopsy specimens revealed fibromuscular dysplasia. The 6 month postoperative course was uneventful. Such a case of external iliac artery aneurysm caused by fibromuscular dysplasia is very rare, and open surgery is recommended for its removal.

Takayasu’s arteritis (TA) is an idiopathic great vessel vasculitis that affects the aorta and its branches. This entity is associated with the major histocompatibility complex (MHC) genes. We studied DNA sequences of human leukocyte antigens (HLA) haplotypes in one pair of Mexican monozygotic twins affected by TA. HLA alleles were determined by sequence-specific priming. Genetic testing of the HLA haplotypes in both sisters were A*02 B*39 DRB1*04 DQB1*03 : 02/A*24 B*35 DRB1*16 DQB1*03 : 01. These results confirm that within the MHC are genes that determine genetic susceptibility to develop TA and sustain genetic heterogeneity of this disease among populations.

A 74-year-old woman who was diagnosed with chronic mesenteric ischemia was under hemodialysis maintenance and had previously undergone axillobifemoral bypass surgery because of abdominal aortoiliac occlusion. Endovascular and antegrade or retrograde surgical revascularizations from the aortoiliac artery were contraindicated because of a severely calcified arteriosclerotic lesion, which included aortoiliac occlusion. During median laparotomy, revascularization consisting of bypass grafting from a previous prosthetic graft to the mesenteric arteries was performed using saphenous vein grafts. Although extra-anatomical bypass for chronic mesenteric ischemia is challenging, it provides a feasible option in cases where conventional endovascular or surgical revascularization is contraindicated.

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.

A 77-year-old man with diabetes presented to our hospital because of left toe gangrene, requiring infrapopliteal revascularization. The patient was on hemodialysis for renal dysfunction. The great saphenous veins had been used for a previous coronary artery bypass. Hence, the small saphenous vein was applied in a popliteal-to-distal posterior tibial artery bypass. The vein graft was passed under the Achilles tendon to reduce graft length, preventing external compression around the ankle. We performed minor amputation and provided negative pressure wound therapy to promote ulcer healing. The wounds healed entirely after two months.

We encountered a case of complex isolated spontaneous celiac artery dissection with a patent false lumen with both entry and re-entry and extensive aneurysmal degeneration of the splenic artery. The dissection entry was wide and was located at the origin of the celiac artery. The false lumen extended to the distal part of the splenic artery, obstructed the true lumen, and was connected to the true lumen at the splenic hilum via the re-entry. Treatment was successful by stent-graft placement for the occlusion of the entry and embolization of the re-entry with microcoils via the false lumen of the splenic artery.

Rupture of inflammatory aortic aneurysm associated with retroperitoneal fibrosis (RF) is rare. We report a 62-year-old man with an inflammatory abdominal aortic aneurysm (IAAA) complicated with idiopathic RF, resulting in a contained rupture of the common iliac artery. The patient also presented with mild renal insufficiency due to urethral obstruction and left hydronephrosis. Surgical procedures including graft replacement and ureterolysis relieved the symptoms. Postoperative immunosuppressive treatment using corticosteroid and methotrexate successfully maintained clinical remission without signs of recurrence of RF and IAAA at the 2-year follow-up.