Recently a hinge point or the maximum bending stress point of the popliteal artery was identified when the knee bends using a lateral view dynamic angiography and a correlation between the lateral view angiography with the extended limb angiography to predict the potential location of the hinge point was defined. A hinge point has been correlated to stent fracture. These findings allowed us to develop a dynamic classification of the popliteal artery. The dynamic classification is useful for endovascular procedures in the popliteal artery. Cultural aspects of our patient population must be considered previous to the endovascular treatment of the popliteal artery, especially to the Japanese culture, which is commonly observed sitting posture such as “seiza (正座).”

Two decades have passed since therapeutic angiogenesis was proposed to promote reparative collateral growth as an alternative therapy for ischemic diseases in patients for whom neither surgical revascularization nor endovascular therapy was suitable. When therapeutic angiogenesis first began, local administration was conducted using recombinant growth factor proteins or gene-encoding growth factors for endothelial cells. Since then, autologous stem cells and endothelial progenitor cell transplantation therapy have been developed. Although many clinical trials have been performed on patients, most therapies have not yet become standard treatments. We have developed a nanoparticle (NP)-mediated, drug-targeting delivery system using bioabsorbable poly-lactic/glycolic acid (PLGA) NPs. In several animal models, pitavastatin-incorporated (Pitava)-NPs showed significant therapeutic effects on critical limb ischemia. Because PLGA NPs are delivered selectively to vascular endothelial cells after intramuscular administration, it is suggested that therapeutic angiogenesis/arteriogenesis plays an important role in the mechanism by which Pitava-NPs exert beneficial therapeutic effects. To translate this to clinical medicine, we have performed studies and produced Pitava-NPs in compliance with good laboratory practice/good manufacturing practice regulations, and completed a phase I/II clinical trial, reporting the safety and efficacy of Pitava-NP intramuscular injection for patients with critical limb ischemia. This review will focus on therapeutic angiogenesis/arteriogenesis for peripheral arterial disease induced by Pitava-NPs.

Recently, the limb salvage rate of patients with critical limb ischemia (CLI) has been improved due to the development of revascularization and wound care treatment. However, many patients with CLI are refractory to standard treatments, including revascularization such as endovascular treatment or surgical bypass. Establishment of a new cell therapy is required to improve the limb salvage rate and prognosis in patients with CLI. In 1997, endothelial progenitor cells were found to be derived from the bone marrow to circulate as CD34 surface antigen positive cells in peripheral blood and to affect therapeutic angiogenesis in ischemic tissues. Later, therapeutic angiogenesis using autologous bone marrow-derived mononuclear cell (BM-MNC) implantation was performed for patients with no-option CLI in clinical practice. Several reports showed the safety and efficacy of the BM-MNC implantation in patients with CLI caused by arteriosclerosis obliterans, thromboangiitis obliterans (TAO), and collagen diseases. In particular, in patients with CLI caused by TAO, limb salvage rate was significantly improved compared with standard treatments. The BM-MNC implantation may be feasible and safe in patients with no-option CLI. Here, we review the efficacy of BM-MNC implantation in no-option CLI, with a focus on therapeutic angiogenesis.

Computed tomography (CT) is a primary imaging modality for the diagnosis of aortic diseases, because of its minimal invasiveness and agility.

Prompt and accurate diagnosis is crucial especially for acute aortic diseases, and the guidelines for acute aortic dissection recommend the use of CT for initial diagnosis. For the follow-up observation of longstanding aortic diseases, the strategy of imaging management by CT must be different from that for emergency and acute phases.

In this review, we document the differences in characteristics and clinical course between aortic aneurysm and aortic dissection and explain the use of recent CT techniques in diagnosing short- and longstanding aortic diseases.

This review evaluates the carotid stump pressure (CSP)’s role as a single parameter at any given pressure as an indicator for selective shunting, or vice versa, in carotid endarterectomy (CEA). A systematic review of literature in MEDLINE and the Cochrane Library from 1969 to 2019 was conducted. The primary end point was set at 0 to 30-day mortality, ischemic stroke (IS), transient ischemic attack (TIA), and a secondary point at recognition of an optimal CSP pressure. The data was subjected to meta-analytics. The odds ratio (OR) was reported at 95% confidence interval (CI). This study has been registered with PROSPERO: CRD42019119851. The pooled analysis on the primary endpoint of IS demonstrated higher incidence of stroke in shunted CEAs solely based on CSP measurement alone (OR, 0.14, 95%CI: 0.08–0.24, I²=48%, p<0.001). Sub group analysis demonstrated similar patterns at 25 mmHg (OR, 0.06, 95%CI: 0.01–0.5, p<0.01), 30 mmHg (OR, 0.07, 95%CI: 0.01–0.63, p=0.02) and 40 mmHg (OR, 0.23, 95%CI: 0.09–0.57, p<0.01). This effect on end points of mortality and TIA demonstrated no benefit in either direction. CSP, as a single criterion, is not a reliable parameter in reduction of TIA, mortality, and IS at any given pressure range.

Venous thromboembolism (VTE) remains highly prevalent in medically ill patients, and often leads to increased mortality and cost burden during hospitalization and post-discharge. Nearly half of all VTEs occur during or after hospitalization, with pulmonary embolism accounting for 10% of inpatient mortality. Appropriate prophylaxis in high-risk medically ill patients has been shown to reduce risk of VTE and related mortality. Despite current evidence-based guidelines, VTE prophylaxis has been under-used. This owes greatly to ambiguity and concerns related to appropriate patient and prophylactic agent selection, and duration of prophylaxis. Because many acutely ill medical patients have multiple comorbidities, the risk of major bleeding must be considered when choosing to implement pharmacological VTE prophylaxis. Multiple risk assessment models have been developed and validated to help estimate VTE and bleeding risks in this population. While studies have shown that the risk for VTE often extends far beyond hospital discharge, there is no evidence to support extending prophylaxis after hospital discharge. The appropriate selection of VTE prophylaxis requires consideration for cost, availability, patient preference, compliance, and underlying comorbidities. Our paper reviews the current evidence and reasoning for appropriate selection of VTE prophylaxis in acutely medical ill patients, and highlights our own approach and recommendations.

Objective: To investigate predictors of acute kidney injury (AKI) following open aortic repair (OAR) requiring suprarenal clamping.

Methods: The study included 833 nonhemodialysis patients who had undergone elective OAR (with suprarenal clamping, n=73; with infrarenal clamping, n=760). We evaluated AKI as defined by the criteria of the Kidney Disease Improving Global Outcomes (KDIGO) and compared in-hospital outcomes between the two groups. We also investigated the effects of AKI on outcomes, factors related to post-suprarenal clamping AKI, and efficacy of hypothermic renal perfusion (HRP) in the suprarenal clamping group.

Results: For the suprarenal vs. infrarenal clamping group, in-hospital mortality was 0% (0/73) vs. 0.5% (4/760). The incidence of AKI was greater in the suprarenal clamping group (37% vs. 15%, P<0.001), and the hospital stay for patients with AKI was longer than for those patients without AKI (median, 21 days vs. 16 days; P=0.005). Renal ischemia time and bleeding volume >1,000 mL were associated with post-suprarenal clamping AKI. Renal ischemia time was longer with HRP (n=15) than without HRP (n=58) (median, 51 min vs. 33 min; P=0.011), and HRP did not decrease the incidence of AKI (40% vs. 36%; P=0.78).

Conclusion: Prolonged renal ischemia and substantial intraoperative bleeding are associated with postoperative AKI following suprarenal clamping.

Objective: To create a web application that can evaluate suture performance and assess its quality.

Material and Methods: We developed the web application using a few cloud computing systems, servers, database, and computing languages. We used 20 anastomosed graft samples for optimizing the application. The images of the anastomosed grafts were captured two-dimensionally. Five vascular surgeons utilized the application to compute the objective score and rank the score of the anastomoses subjectively.

Results: Steps for using the application include uploading a two-dimensional image of sutures, tracing the stitch line manually, and pushing the button to have the score displayed. After using this system for more than 1,000 times without server issues or failures, we confirmed its stability and easy accessibility. The system calculated the score within several seconds. The score of the three factors (bite, pitch, and skewness of angle) ranged from 0.25 to 0.76. The error range of the application was acceptable. The interclass correlation coefficient (ICC (2,1)) of the three factors was 0.92.

Conclusion: The quality of the application was acceptable considering the low range of interoperator variations in the scores.

Objective: Clinical guidelines have long recommended referring patients with clerical limb ischemia (CLI) to a vascular specialist early in the course of their disease to plan for revascularization options. However, no data were so far available on how promptly CLI patients were referred to a vascular center in the real-world settings in Japan. This study aimed to survey the duration from wound occurrence to referral to a vascular center in CLI patients in Japan.

Materials and Methods: We analyzed a database of a prospective, multicenter registry in Japan, including 428 CLI patients presenting ischemic wounds and referred to vascular centers. The duration of the wound occurrence was surveyed at registration.

Results: The wound duration exceeded 1 month in 58.2% [95% confidence interval: 53.2% to 63.1%] of the patients, and 3 months (i.e., one season) in 15.9% [12.4% to 19.4%]. No clinical features were significantly associated with the wound duration. The wound duration was independently associated with the wound severity evaluated using the Wound, Ischemia, and foot Infection classification system (P=0.030).

Conclusion: A substantial number of CLI patients referred to vascular centers had a long duration of wounds, i.e., time from wound occurrence to the referral.

Objective: We aimed to determine predictors of poor long term quality of life, using the VEINES Quality of Life (QOL) questionnaire, in patients with lower limb deep venous thrombosis (DVT).

Material and Methods: This study included adult patients with primary lower limb DVT between January 2007 and December 2017. Post thrombotic syndrome (PTS) was assessed using the Villalta score and Quality of Life (QoL) by the VEINES quality of life questionnaire.

Results: Our study included 125 patients, 57 (45.6%) of whom were males. The patient population’s median age was 41 years (IQR: 34–47 years). The median follow up was 450 days (IQR: 390–1020 days). PTS occurred in 49 (39.2%) patients. Independent predictors of poor quality of life post DVT were progression to PTS, complete occlusion of vein, proximal (Ileofemoral) DVT, poor control of INR, poor compliance with compression stockings, severity of PTS, ileofemoral DVT and poor control of therapeutic anticoagulation.

Conclusion: Predictors who are independently associated with poor quality of life post DVT are PTS, inability to maintain therapeutic anticoagulation and ileofemoral DVT.

A 65-year-old male who presented with dizziness, dysarthria, and disability of his left hand was admitted to our hospital. Magnetic resonance imaging of the head revealed cerebral infarction and enhanced computed tomography revealed a suspicious thrombus in the ascending aorta. He did not have a coagulation disorder. We performed ascending aortic replacement and removed the thrombus with the aortic wall in order to avoid any recurrences. Here we report the successful treatment of the case from clinical and pathological points of view with some findings.

We report the case of a 83-year-old man with aneurysmal sac enlargement after endovascular aneurysm repair for an abdominal aortic aneurysm, despite no overt endoleak (EL) detected on imaging. Occult type II EL was suspected, and treatment was performed. However, the aneurysm continued to enlarge. Thus, we diagnose with type V EL as exclusion diagnosis. We combined an aortic cuff and stent-graft leg to cover the initially inserted stent graft, as a diagnostic treatment for unrefined type IIIb EL. Subsequently, the aneurysm diameter decreased. This technique and concept may be effective for type V EL, which may include another type occult EL.

The present report describes a case of mega-aortic syndrome accompanied with severe aortic regurgitation in a 75-year-old man who underwent a two-stage hybrid repair. Intraoperative pathologic findings at the first repair, consisting of Bentall operation and total arch replacement with a Lupiae graft, aided the identification of the giant cell aortitis. Despite complicating hemorrhagic stroke, steroid therapy was initiated and endovascular repair was subsequently completed. Over more than 2 years of follow-up, the patient continued steroid therapy and is doing well without any reintervention.

Aortoduodenal syndrome is a rare duodenal obstruction caused by an abdominal aortic aneurysm. Current treatment involves open aneurysmal repair according to the theory that this procedure releases the duodenum from mechanical compression. However, the mechanism of duodenal blockage remains unclear and reports of endovascular aneurysm repair (EVAR) for aortoduodenal syndrome are quite rare. We report our successful case of EVAR for aortoduodenal syndrome without aneurysmal shrinkage and discuss the mechanism of duodenal obstruction.

Ischemic limbs with infected heel ulcers are often difficult to salvage. We present a case of an 82-year-old woman who had bilateral heel ulcers owing to chronic limb-threatening ischemia. She underwent right femoral-terminal posterior tibial artery bypass surgery, but right calcaneus osteomyelitis occurred and inhibited wound healing. She underwent partial calcanectomy (PC), and her right heel healed six months after the bypass surgery. The ulcer on her left foot also healed after distal bypass and PC. We describe our experience with a patient who needed PC to cure her heel ulcers.

Aortoenteric fistula (AEF) after endovascular aortic repair (EVAR) is a rare complication, with only 32 cases reported previously. A 71-year-old man who presented with severe duodenal bleeding due to primary AEF (PAEF) underwent successful EVAR. Four years later, the AEF recurred because of dilatation of the aneurysm sac. He underwent emergent surgery, removal of the stent graft, and replacement of an artificial bifurcated graft with placement of a greater omental flap. EVAR for PAEF was an effective option for acute treatment, but it caused refistulization in the long term. EVAR should be considered as a bridge therapy to definitive surgery.

The pressure gap between the aortic lumen and bronchial air spaces makes hemoptysis the most frequent feature of aortobronchial fistula (ABF). However, air migration can be a rare cause of ABF. The literature has demonstrated some “indirect routes” that would serve as a bridge between ABF and consecutive air migrations. However, evidence suggesting the presence of a “direct route” between them is lacking. We present an extremely rare case of newly onset cough-induced “perigraft space ABF” and ABF-related air migration in the remnant aneurysm sac occurring 3 years after an aortic surgery and a near-misdiagnosis of a delayed graft infection.

Pulmonary embolectomy is an effective treatment of acute pulmonary embolism (APE) but not for chronic pulmonary thromboembolism. We described surgical experience of two patients with APE in preexistent unidentified chronic pulmonary thromboembolism. One patient who presented with severe hypoxia but stable hemodynamics underwent successful pulmonary endarterectomy for proximal organized thrombus instead of pulmonary embolectomy. The other patient who required extracorporeal membrane oxygenation for severe hypoxia developed right heart failure because of residual distal organized thrombus after pulmonary embolectomy. Clinical and radiographical presentation of APE in chronic pulmonary thromboembolism mimics APE, and thus, candidates of pulmonary embolectomy should be carefully selected.

We present the case of a 73-year-old man with stent graft infection, who had undergone thoracic endovascular aortic aneurysm repair with a supra-aortic bypass from the right axillary to the left common carotid and axillary arteries. The procedure included total stent graft removal, radical debridement, and in situ graft replacement via left anterolateral thoracotomy. Cerebral perfusion from the left axillary artery and cardioplegia using an occlusion balloon with moderate hypothermia were performed to reinforce organ protection. Staged omentopexy was performed the next day after initial replacement with non-contaminated instruments. The postoperative course was uneventful. No recurrence of infection has been found for 3 years.

A 66 year-old man with a previous history of Sjögren’s syndrome was admitted with anastomotic pseudoaneurysm and aortic dissection in the ascending aorta, which developed after Bentall’s surgery, a procedure that has severe complications and high mortality. Using the reverse extra-anatomical aortic arch debranching technique, zone 0 thoracic endovascular aortic repair was performed emergently. The postoperative course was uneventful. Twenty months later, computed tomography showed remodeling of the dissection, resolution of the pseudoaneurysm, and patency of the reverse extra-anatomical aortic arch debranching graft.