Superficial femoral artery pseudoaneurysm at implantation site of drug eluting stent discovered due to bacteremia: A case report.

BACKGROUND: Drug-eluting stents (DES) are used to treat lower extremity arterial disease. During DES treatment, aneurysmal degeneration occasionally occurs, especially with fluoropolymer-based DES. However, the incidence of pseudoaneurysms after DES placement is rarely reported in the lower extremity region, although there have been several reports on pseudoaneurysm formation after DES pla-cement in the coronary artery region. CASE SUMMARY: We report the case of a 64-year-old man who presented with fever and pain in his left hand after dialysis. Bacteremia was diagnosed by blood culture, and after admission, he developed pain on the medial side of the right thigh. A pseudoaneurysm was observed in the right superficial femoral artery (SFA) at the proximal end of a previously placed DES. The bacteremia was thought to have been caused by a pseudoaneurysm of the left superficial brachial artery, and the pseudoaneurysm of the left superficial brachial artery was removed after antibiotic treatment. The pseudoaneurysm of the right SFA rapidly expanded after admission, but the expansion rate was reduced after infection control. Seven months after the first admission, the pseudoaneurysm of the left SFA was re-moved and in situ revascularization performed using a rifampicin-soaked Dacron graft. CONCLUSION: Although pseudoaneurysm after DES placement in the lower extremity region is rare, it must be considered in patients with bacteremia.

Endovascular repair of an abdominal aortic aneurysm with external iliac artery occlusion using VBX as the contralateral leg via axillary delivery: A case report.

RATIONALE: A hostile iliac access route is an important consideration when enforcing endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAA). Herein, we report a case of AAA with unilateral external iliac artery occlusion, for which bifurcated EVAR was successfully performed using a single femoral and brachial artery access. PATIENT CONCERNS: A 76-year-old man who had undergone surgery for lung cancer 4.5 years prior was diagnosed AAA by computed tomography (CT). DIAGNOSIS: Two and a half years before presentation, CT revealed an infrarenal 48 mm AAA, which had enlarged to 57 mm by 2 months preoperatively. CT identified occlusion from the right external iliac artery to the right common femoral artery, with no observed ischemic symptoms in his right leg. The right external iliac artery, occluded and atrophied, had a 1 to 2 mm diameter. INTERVENTION: Surgery was commenced with the selection of a Zenith endovascular graft (Cook Medical) with an extended body length. Two Gore Viabahn VBX balloon expandable endoprosthesis (VBX; W.L. Gore & Associate) were delivered from the right axilla as the contralateral leg. OUTCOMES: CT scan on the 2nd day after surgery revealed no endoleaks. LESSONS: While the long-term results remain uncertain, this method may serve as an option for EVAR in patients with unilateral external iliac artery occlusion.

Successful treatment of giant abdominal aortic aneurysm with chronic contained rupture diagnosed at the onset of acute retrograde type A aortic dissection: A case report.

INTRODUCTION: It is rare for two critical diseases, namely a giant abdominal aortic aneurysm (AAA) and acute type A aortic dissection (TAAD), to be detected simultaneously, and in such instances, management is extremely difficult. PRESENTATION OF CASE: A 64-year-old man who presented to our hospital with a chief complaint of sudden back pain and vomiting was diagnosed with acute retrograde TAAD and a giant AAA with chronic contained rupture (CCR) via computed tomography. We initially managed the acute TAAD conservatively and subsequently performed laparotomy for the AAA 3 months later. During open surgery, we performed vascular reconstruction using a tailor-made tapering graft. DISCUSSION: Emergency surgery is recommended for AAA with CCR or retrograde TAAD with a patent false lumen, and the prognosis of conservative treatments for these cases is currently unknown. However, concurrent surgery for this condition is extremely invasive. Fortunately, the patient in this case survived the acute phase, and laparotomy for the AAA could be safely performed during the chronic phase of the TAAD. CONCLUSION: We successfully treated a giant AAA with CCR by selecting the appropriate surgical timing and method. In cases of combined CCR of a giant AAA and retrograde TAAD, conservative management may be attempted to convert the acute dissection to a chronic one, thereby allowing elective repair of the AAA.

Ventricular fibrillation during carotid endarterectomy and bailout stenting: a case report.

BACKGROUND: Carotid artery manipulation is not a special technique but reports of intraoperative ventricular fibrillation are rare. The risk of fatal arrhythmias may be hidden behind routine surgical techniques and anesthetic management. We focused on QT prolongation and QT dispersion. CASE PRESENTATION: A 77-year-old man underwent carotid endarterectomy and bailout stenting. Although there were no obvious preoperative risk factors for intraoperative ventricular tachyarrhythmia, ventricular fibrillation (VF) had occurred during a maneuver of the carotid artery under hypercapnia. QTc was prolonged from 317 ms before surgery to 458 ms before the onset of VF. QTc dispersion between leads II and III was also increased to 50 ms. Hypomagnesemia was noted after resuscitation by electrical defibrillation, adrenaline, and noradrenaline. CONCLUSIONS: We considered that the combination of multiple risk factors led to the development of ventricular fibrillation. It should be noted that carotid artery manipulation has the potential to cause arrhythmias.

A Radiation-Crosslinked Gelatin Hydrogel That Promotes Tissue Incorporation of an Expanded Polytetrafluoroethylene Vascular Graft in Rats.

A prosthetic vascular graft that induces perigraft tissue incorporation may effectively prevent serious sequelae such as seroma formation and infection. Radiation-crosslinked gelatin hydrogel (RXgel) mimics the chemical and physical properties of the in vivo extracellular matrix and may facilitate wound healing by promoting tissue organization. Fibroblasts cultured on RXgel actively migrated into the gel for up to 7 days. RXgels of three different degrees of hardness (Rx[10], soft; Rx[15], middle; Rx[20], hard) were prepared, and small disc-like samples of RXgels were implanted into rats. In vitro and in vivo results indicated that Rx[10] was too soft to coat vascular grafts. Thus, expanded polytetrafluoroethylene (ePTFE) vascular grafts coated with RXgel were developed using Rx[15] and Rx[20] gels, and ring-shaped slices of the graft were implanted into rats. Alpha-smooth muscle actin (αSMA) and type III collagen (Col-III) levels were detected by immunohistochemistry. Immunohistochemical staining for αSMA and Col-III demonstrated that RXgel-coated vascular grafts induced more granulation tissue than non-coated grafts on days 14 and 28 after implantation. RXgel-coated ePTFE vascular grafts may provide a solution for patients by reducing poor perigraft tissue incorporation.

Carotid Stump Pressure and Contralateral Internal Carotid Stenosis Ratio During Carotid Endarterectomies: 1D-0D Hemodynamic Simulation of Cerebral Perfusion.

Objective: We selectively place carotid shunting when ipsilateral mean stump pressure is less than 40 mmHg during carotid endarterectomy (CEA). This study aimed to assess the validity of our selective shunting criterion by 1D-0D hemodynamic simulation technology. Materials and Methods: We retrospectively reviewed 88 patients (95 cases) of CEA and divided them into two groups based on the degree of contralateral internal carotid artery (ICA) stenosis ratio, which was determined as severe when the peak systolic velocity ratio of the ICA to the common carotid artery was ≥4 by carotid duplex ultrasonography. Patients with severe stenosis or occlusion in contralateral ICA were classified as hypoperfusion group, and those without such contralateral ICA obstruction were classified as control group. Results: Perioperatively, the mean carotid stump pressures were 33 mmHg in hypoperfusion group and 46 mmHg in the control group (P=0.006). We simulated changes in carotid stump pressure according to the changes in the contralateral ICA stenosis ratio. 1D-0D simulation indicated a sharp decline in carotid stump pressure when the contralateral stenosis ratio was >50%, while peripheral pressure of the middle cerebral arteries declined sharply at a ≥70% contralateral stenosis ratio. At this ratio, the direction of the ipsilateral cerebral arterial flow became inverted, the carotid stump pressure became dependent on the basilar artery circulation, and the ipsilateral middle cerebral artery became hypoperfused. Conclusion: Our clinical and computer-simulated results confirmed the validation of our carotid shunting criterion and suggested that contralateral ICA stenosis ratio over 70% is a safe indication of selective shunting during CEA.

A comparison of subjective clinical and objective judgement of abdominal aortic aneurysm morphology.

BACKGROUND: We compared the subjective, clinical judgement of "saccular" morphology with the objective judgement of mechanical structural analysis. METHODS: Using structural analysis with the finite element method, we previously created a simple model of abdominal aortic aneurysm (AAA) that visualized the distribution of the maximum principal stress (MPS) in the aortic wall and identified the area of prominent stress. AAA "saccular" morphology was determined according to the area showing MPS>0.03 MPa. AAAs with low aspect ratio (horizontally long AAA sac) and small fillet radius were defined as "saccular." Twelve vascular surgeons were recruited. First, they judged the AAA as saccular or fusiform with 3-dimensional images at their clinical impression (subjective "eyeball" judgement). Second, they applied the deformable figure tools on the simple AAA-shaped sagittal view in the application model for 30 AAA cases. From the data of the tools applied, the mechanical structural analysis was performed semi-automatically and the morphology was judged with the objective "simple application." RESULTS: The structural analysis revealed that only one case was judged as saccular by 11 out of 12 surgeons and the other 29 AAAs were judged as fusiform by two-thirds or more of the surgeons. In contrast, 5 cases were subjectively judged as saccular by eight and more of the surgeons. CONCLUSIONS: The clinical judgement of AAA saccular morphology by the vascular surgeons was different from the judgement derived from the mechanical structural analysis using the application model. The saccular morphology may be theoretically rare in AAAs.

High aneurysm wall enhancement values are associated with late sac shrinkage after endovascular repair of abdominal aortic aneurysms.

ABSTRACT: To analyze the correlation between aneurysm wall enhancement (AWE) values and early and late sac shrinkage after endovascular aneurysm repair (EVAR).We retrospectively analyzed 28 patients who underwent EVAR for abdominal aortic aneurysms (AAA) using a bifurcated main body stent graft. The value of AWE in the slice of the maximum AAA diameter was measured using a volumetric analysis of computed tomography images. Sac measurements before EVAR and more than 10 months after EVAR were compared, and the maximum sac shrinkage rate was calculated.The AWE value immediately after (4 to 7 days) EVAR correlated positively with the sac shrinkage rate (R2 = 0.0139). The AWE value at 6 months after EVAR was also strongly correlated with the sac shrinkage rate (R2 = 0.4982).Higher AWE values at 6 months after EVAR were strongly associated with the sac volume shrinkage rate. High AWE values may be a predictive factor for sac shrinkage and may aid in the selection of the appropriate clinical strategy after EVAR.

A case of endovascular therapy for treating idiopathic arterial deteriorations of unknown etiology.

INTRODUCTION: Peripheral artery pseudoaneurysm as a consequence of arterial deterioration is relatively rare in young populations, who typically lack an atherosclerotic background. Such pseudoaneurysms are known to pose a risk of rupture, which is correlated with high mortality and morbidity rates. Pseudoaneurysms are more prone to rupture than true aneurysms are, as their vessel walls tear more easily. We present the case of a 50-year-old patient who had multiple arterial deteriorations. CASE PRESENTATION: The patient experienced backache, and computed tomography revealed a tear of the right renal artery, and a pseudoaneurysm of the left internal iliac artery. He had a history of graft replacement for the right superficial artery pseudoaneurysm, which had been occluded. Although various tests were performed for differential diagnosis, the etiology was unidentified. Considering the suspected vascular fragility and failure of previous direct intervention, these 2 lesions were treated by placing endografts simultaneously. DISCUSSION: We investigated various diseases causing vascular fragility in the reported case, such as vascular Behçet disease, vascular Ehlers-Danlos syndrome, fibromuscular dysplasia, and segmental arterial mediolysis. However, these were all excluded and the etiology remains unclear. Progress in endovascular techniques enables the use of minimally invasive treatment in patients with vascular fragility. CONCLUSION: When vascular fragility may exist, endovascular treatment is a desirable option, as it can be performed repetitively and is less invasive.

Development of a Web Application That Evaluates Suture Performance in Off-the-Job Training.

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.

Egg-shell like Calcification as a Protective Factor for Splenic Artery Aneurysm Dilatation.

BACKGROUND: The purpose of this study was to evaluate the factors associated with asymptomatic splenic artery aneurysm (SAA) dilatation. METHODS: Among patients with SAA admitted to our department from 2001 to 2018, 70 lesions in 59 patients were selected and analyzed retrospectively. There were no cases of rupture or pregnancy in the follow-up period. We defined egg-shell appearance as SAA with >75% calcification of the outer shell. We measured the dilatation rate (mm/year) and evaluated the comorbidity and anatomical factors using univariate and multiple linear regression models. Post-hoc multiple linear regression models were fitted to evaluate the possible interactions. RESULTS: The mean age was 61.4 years (range 35-85 years), and the initial aneurysm diameter was 15.1 mm (range 3-47 mm). The mean dilatation rate was 0.26 mm/year (range 0-3.2 mm/year) during the follow-up period (average 4.6 years). Univariate analysis revealed that, portal hypertension (PHT) (P = 0.0003), egg-shell appearance (P = 0.007), and aneurysm diameter > 20 mm (P = 0.05) were significantly associated with the dilatation rate. Multivariate analysis revealed that egg-shell appearance was found to be an independent inverse risk factor of dilatation rate (P = 0.006). The multivariate analysis, including interaction terms, revealed a stronger effect of PHT and diameter >20 mm in cases with no egg-shell appearance (P = 0.08 and P = 0.05 for interactions, respectively). CONCLUSIONS: The egg-shell appearance of SAA was an independent inverse risk factor affecting the SAA dilatation rate. The dilatation rates in the case of PHT and diameter >20 mm were restricted in the presence of the egg-shell appearance.

Effect of drug-coated balloons in treatment of stenosis of the femoral artery and vein bypass graft not responding to plain old balloon angioplasty: a case report.

BACKGROUND: The use of drug-coated balloons (DCBs) with anti-proliferative agents in treating femoropopliteal lesions was approved in Japan in 2017. A better limb salvage rate or amputation-free rate of DCBs relative to plain old balloon angioplasty (POBA) has been reported; however, there is little evidence of the direct effect on intimal hyperplasia (IH). CASE PRESENTATION: A 70-year-old man with chronic limb-threatening ischemia and foot gangrene had undergone bypass surgery from the left common femoral artery to the dorsalis pedis artery 2 years earlier. We evaluated the bypass graft using ultrasonography and found stenosis around the proximal anastomotic site, presumably due to IH. POBA was performed every 3 months due to the repeated re-stenosis of the lesion. Since using the DCB, no restenosis has been detected to date (10 months). CONCLUSION: DCB might be an effective tool for treating re-stenosis due to IH or vein grafts that do not respond to POBA.

Phlegmasia cerulea dolens as an initial manifestation of a fistula between a ruptured iliac artery aneurysm and the iliac vein.

Phlegmasia cerulea dolens (PCD) is caused by obstruction of limb venous return that may result in venous gangrene and limb loss. We present a case of a fistula between a ruptured right common iliac artery aneurysm and the left common iliac vein (ilioiliac arteriovenous fistula [AVF]), which initially manifested as left PCD and acute renal failure. Resection of the aneurysm and repair of the AVF immediately improved the PCD and acute renal failure. We should be aware that an iliac AVF might present as PCD and should keep this in mind.

Original Homebuilt Off-the-Job Training System for Vascular Surgeons: System Analysis and Assessment.

Objective: We assessed the effectiveness and appropriateness of our original off-the-job training (Off JT) system using data acquired from recruited medical students and doctors. Materials and Methods: We presented our original homebuilt Off JT system, which is simple and inexpensive. In our unique system, we performed anastomosis at the bottom of a plastic pot, which mimics the actual open surgical procedure at a deep site. There were four evaluation points: (A) operating time, (B) performance of anastomosis by semi-automatically analyzing the image with the coefficient of variation (standard deviation/length) of the "bite" and the "pitch," (C) scoring of the total surgical skill evaluated by the trainers according to the Operative Performance Rating System (OPRS), and (D) the relationship of these three factors (A, B, and C). Results: The procedural time and coefficient of variation of the bite and pitch decreased and the OPRS score increased after training. There was a strong correlation between procedural time, anastomotic performance, and OPRS score. Conclusion: The effectiveness of our original homebuilt system was shown by reduced procedural time, improved anastomotic quality, and increased OPRS score.

Theoretical mechanism of temporary renal function improvement after abdominal aortic aneurysm surgery: Applications for clinical imaging and laboratory data.

We evaluated the effects of changes in blood flow due to abdominal aortic aneurysm (AAA) surgery by using a simple zero-dimension model and applied theoretical values to clinical data.The zero-dimension electronic circuit model and diagram of blood flow distribution were created by setting the resistance of the aorta, bilateral iliac arteries, renal arteries, and aneurysm. Resistance of the aneurysm and resistance of the aorta before surgery were compared with that of the aorta after surgery. We set the radius length of each anatomical parameter to calculate theoretical values.Renal flow increased 13.4% after surgery. Next, we analyzed contrast-enhanced computed tomography data of 59 patients who underwent AAA surgery. A total of 19 patients were treated with a Y graft and 7 patients were treated with a straight graft during open surgery. However, 33 patients were treated with a bifurcated stent graft. A significant linear relationship between the increased estimated glomerular filtration rate (eGFR) ratio and the decreased aneurysm ratio was found only for the straight graft group.Using a circuit model, renal blood flow theoretically increased after AAA surgery. Clinically, there was a correlation between volume regression and eGFR improvement only in the limited AAA group.

Acute aortic occlusion in a patient with chronic paralysis due to spinal cord injury: a case report.

Patients with spinal cord injury experience changes in the cardiovascular system and a high morbidity associated with peripheral artery disease. We report a case of acute aortic occlusion in a patient with chronic paralysis due to spinal cord injury. A 65-year-old man with chronic paralysis due to spinal cord injury developed mottling of the right extremity. Because of the complete tetraplegia, the patient had no subjective symptoms. Computed tomography revealed occlusion of the infrarenal abdominal aorta. An emergency thromboembolectomy established adequate blood flow, and the postoperative course was uneventful. The loss of muscle mass might be an advantage in avoiding ischemia reperfusion syndrome. Early detection of acute aortic occlusion and immediate reperfusion are primarily important, but patients with chronic paralysis present a risk of delay in detection, diagnosis, and treatment of acute aortic occlusion because of motor or sensory deficits. Although rare, it is necessary to consider acute aortic occlusion in the case of acute limb ischemia in patients with chronic paralysis due to spinal cord injury.

Long-Term Results of Treatment for Critical Limb Ischemia.

From 2001 to 2012, arterial reconstruction was performed in 306 out of 497 limbs (62%) with critical limb ischemia. The reasons for non-vascularization include high operative risk (36%), extended necrosis or infection (20%), and technical issues (15%). Cumulative patency and limb salvage in collagen disease were significantly worse compared to arteriosclerosis obliterans. Cumulative limb salvage, amputation free survival (AFS), and major adverse limb event and perioperative death (MALE + POD) in patients with end-stage renal disease (ESRD) were significantly worse compared to patients without ESRD, but not significant with regards to graft patency. Our finding suggests that aggressive arterial reconstruction provides satisfactory long-term results in critical limb ischemia so long as case selection for revascularization is properly made. (This article is a translation of J Jpn Coll Angiol 2014; 54: 5-11.).

Development of an Image-Based Modeling System to Investigate Evolutional Geometric Changes of a Stent Graft in an Abdominal Aortic Aneurysm.

BACKGROUND: Quantification of geometric changes of the stent graft (SG) in abdominal aortic aneurysm has been required for follow up of endovascular aneurysm repair (EVAR). The aim was to develop an image-based modeling system (V-Modeler) to investigate these changes over time. METHODS AND RESULTS: V-Modeler was applied to investigate the migration of the SG. Three sets of computed tomography images were taken at 3 different times: (1) 5 days after the implantation; (2) 7 months later when the unilateral leg migrated upward; and (3) 10 months later when the limb had migrated into the common iliac aneurysm resulting in a type 1b endoleak. A spline function was used to represent the center lines of the SG to track its evolutional geometric changes in a three-dimensional manner. The characteristics of vascular geometry, as well as the SG geometry using geometric parameters such as length, curvature, torsion, angle of tangent vector (ATV), and migrated length, was evaluated. It was observed that the strong peak of the curvature in the distal area appeared, and a conversion of the torsion disappeared chronologically. CONCLUSIONS: The V-Modeler was developed, which not only can extract vascular geometry but also can identify geometric parameter, such as curvature, torsion, and ATV, to predict adverse events following EVAR.

Biomechanical analysis of an aortic aneurysm model and its clinical application to thoracic aortic aneurysms for defining "saccular" aneurysms.

BACKGROUND: We aimed to develop a simple structural model of aortic aneurysms using computer-assisted drafting (CAD) in order to create a basis of definition for saccular aortic aneurysms. METHODS AND RESULTS: We constructed a simple aortic aneurysm model with 2 components: a tube similar to an aorta and an ellipse analogous to a bulging aneurysm. Three parameters, including the vertical and horizontal diameters of the ellipse and the fillet radius, were altered in the model. Using structural analysis with the finite element method, we visualized the distribution of the maximum principal stress (MPS) in the aortic wall and identified the area(s) of prominent stress. We then selected patients with thoracic aortic aneurysms in whom the aneurysm expansion rates were followed up and applied the theoretical results to the raw imaging data. The maximum MPS drastically increased at areas where the aspect ratio (vertical/horizontal) was <1, indicating that "horizontally long" hypothetical ellipses should be defined as "saccular" aneurysms. The aneurysm expansion rate for the patients with thoracic aneurysms conforming to these parameters was significantly high. Further, "vertically long" ellipses with a small fillet might be candidates for saccular aneurysms; however, the clinical data did not support this. CONCLUSIONS: Based on the biomechanical analysis of a simple aneurysm model and the clinical data of the thoracic aortic aneurysms, we defined "horizontally long" aortic aneurysms with an aspect ratio of <1 as "saccular" aneurysms.