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Yoshihiro Tanaka Tsuyoshi Yoshimuta Keiichi Kimura Kenji Iino Yudai Tamura Kenji Sakata Kenshi Hayashi Hirofumi Takemura Masakazu Yamagishi Masa-aki Kawashiri 《Journal of vascular surgery》2018,67(4):1127-1133
Objective
Spontaneous isolated visceral artery dissection (SIVAD) involving the celiac artery or superior mesenteric artery is rare, but it can be fatal. Given its rare incidence, the clinical characteristics of SIVAD are not fully understood. Therefore, the aim of this study was to investigate the clinical characteristics and prognosis of SIVAD.Methods
We retrospectively reviewed 39 consecutive patients diagnosed with SIVAD from January 2007 to December 2016. Demographic characteristics, symptoms, vital signs, blood examination results, and computed tomography findings were retrieved through medical record review.Results
The median age of the patients was 52 years; 94.9% were male, and 64.1% were symptomatic. Median follow-up duration was 11 months. Overall, hypertension (48.7%) and smoking (79.5%) were frequently observed. There were significant differences between symptomatic and asymptomatic patients in white blood cell count and creatine kinase level but not in fibrin degradation products or D-dimer level. There was a significant correlation between symptoms and length of dissection on computed tomography (P < .01). Conservative treatment was performed in 32 patients (82.1%), and only 7 patients required open surgery or intravascular intervention. Notably, the diameter of affected vessels decreased spontaneously with no rupture or symptom recurrence during follow-up, and mortality was 0% at both 30 days and 1 year.Conclusions
The utility of blood examination, especially for fibrin degradation products and D-dimer levels, for diagnosis of SIVAD is limited. A high index of suspicion is warranted in patients presenting with persistent severe abdominal pain. Conservative treatment should be considered first-line therapy in patients without any signs of bowel ischemia or rupture. 相似文献57.
Hanaa Dakour Aridi Isibor Arhuidese Melissa Scudder Thomas Reifsnyder Mahmoud B. Malas 《Journal of vascular surgery》2018,67(5):1606-1612.e4
Objective
Arteriovenous grafts (AVGs) remain reliable substitutes for permanent hemodialysis access in scenarios that preclude the placement of native arteriovenous fistulas (AVFs). The majority of AVGs are constructed of expanded polytetrafluoroethylene (ePTFE), which is relatively inexpensive and readily available, but synthetic AVGs have poor patency rates. On the other hand, biologic grafts confer an advantage by virtue of their inherent similarity to the native human vasculature. However, evidence to support the current preference of synthetic conduits over biologic grafts in clinical practice is scarce. The aim of this protocol is to propose a contemporary re-evaluation and comparison between ePTFE and bovine carotid artery (BCA) grafts.Methods
This prospective randomized controlled trial is being conducted at an academic hospital center. A total of 100 patients at least 18 years of age and undergoing AVG placement will be recruited and prospectively randomized into two parallel groups with a 1:1 allocation ratio. Patients eligible to receive AVF and those with a known allergic reaction or history of intolerance to any ePTFE or BCA component will not be included in the study. Moreover, patients with a recent active infection at the site of previous AVG placement and patients with a bleeding disorder, an active malignant disease, or a life expectancy <1 year or who refuse blood transfusion and pregnant women will be excluded. Patients will receive either BCA (experimental) or standard ePTFE grafts (control) in compliance with the National Kidney Foundation Kidney Disease Outcomes Quality Initiative guidelines for AVG creation. Primary end points include primary, primary assisted, secondary, and functional patency at 1 year and 2 years after graft placement. Secondary outcomes include complications (pseudoaneurysms, infections, and steal syndrome) and reintervention rates during the first and second postoperative years. Outcomes will be assessed and documented every 6 months.Results
Once the study is completed, analysis of the data will be performed using univariate methods, and Kaplan-Meier and multivariate Cox proportional regression analyses will be employed to evaluate and to compare outcomes between BCA and ePTFE over time.Conclusions
The creation of a functional and durable dialysis vascular access is crucial in the treatment of patients with end-stage renal disease and is a challenging quest for vascular surgeons. The proposed study compares the outcomes of synthetic and biologic AVG options in patients who are poor candidates for a native AVF. This will help derive contemporary evidence and improve the care of vascular access patients. 相似文献58.
Amir A. Ghaffarian Claire L. Griffin Larry W. Kraiss Mark R. Sarfati Benjamin S. Brooke 《Journal of vascular surgery》2018,67(2):529-535.e1
Objective
Basilic vein transposition (BVT) fistulas may be performed as either a one-stage or two-stage operation, although there is debate as to which technique is superior. This study was designed to evaluate the comparative clinical efficacy and cost-effectiveness of one-stage vs two-stage BVT.Methods
We identified all patients at a single large academic hospital who had undergone creation of either a one-stage or two-stage BVT between January 2007 and January 2015. Data evaluated included patient demographics, comorbidities, medication use, reasons for abandonment, and interventions performed to maintain patency. Costs were derived from the literature, and effectiveness was expressed in quality-adjusted life-years (QALYs). We analyzed primary and secondary functional patency outcomes as well as survival during follow-up between one-stage and two-stage BVT procedures using multivariate Cox proportional hazards models and Kaplan-Meier analysis with log-rank tests. The incremental cost-effectiveness ratio was used to determine cost savings.Results
We identified 131 patients in whom 57 (44%) one-stage BVT and 74 (56%) two-stage BVT fistulas were created among 8 different vascular surgeons during the study period that each performed both procedures. There was no significant difference in the mean age, male gender, white race, diabetes, coronary disease, or medication profile among patients undergoing one- vs two-stage BVT. After fistula transposition, the median follow-up time was 8.3 months (interquartile range, 3-21 months). Primary patency rates of one-stage BVT were 56% at 12-month follow-up, whereas primary patency rates of two-stage BVT were 72% at 12-month follow-up. Patients undergoing two-stage BVT also had significantly higher rates of secondary functional patency at 12 months (57% for one-stage BVT vs 80% for two-stage BVT) and 24 months (44% for one-stage BVT vs 73% for two-stage BVT) of follow-up (P < .001 using log-rank test). However, there was no significant difference between groups in use of interventions (58% for one-stage BVT vs 51% for two-stage BVT; P = .5) to maintain patency. These findings were confirmed in multivariate analysis, in which two-stage BVTs were associated with a significantly lower rate of failure (hazard ratio, 0.39; 95% confidence interval, 0.2-0.8; P < .05) than one-stage BVTs after controlling for confounding variables. Finally, the two-stage BVT was more cost-effective (3.74 QALYs for two-stage BVT vs 3.32 QALYs for one-stage BVT) during 5 years, with an incremental cost-effectiveness ratio of $4681 per QALY.Conclusions
Our data show that two-stage BVTs are more durable and cost-effective than one-stage procedures, with significantly higher patency and lower rates of failure among comparable risk-stratified patients. These findings suggest that additional upfront costs and resources associated with creating two-stage BVTs are justified by their long-term outcomes. 相似文献59.
Hillary B. Alberta Toshio Takayama Annalise Panthofer Richard P. Cambria Mark A. Farber William D. Jordan Jon S. Matsumura 《Journal of vascular surgery》2018,67(2):382-388
Objective
We evaluated images of patients undergoing a thoracic endovascular aortic repair procedure using two reference points as a means for differentiating stent graft migration from aortic elongation. Conventional standards define migration of a stent graft as an absolute change in the distance from the distal graft ring to a distal landmark ≥10 mm compared with a baseline measurement. Aortic elongation occurs over time in both healthy individuals and patients with aortic disease. Aortic elongation in patients with stent grafts may result in increased distal thoracic aortic lengths over time. False-positive stent graft migration would be defined when these patients meet the standard definition for migration, even if the stent has not moved in relation to the elongating aorta.Methods
This retrospective study evaluated the aortic length of 23 patients treated with the conformable GORE TAG thoracic endoprosthesis (W. L. Gore & Associates, Flagstaff, Ariz) in three clinical trials (dissection, traumatic injury, and aneurysm). Patients who met the standard definition for migration were selected. A standardized protocol was used to measure aortic centerline lengths, including the innominate artery (IA) to the most distal device ring, the IA to the celiac artery (CA), and the distal ring to the CA. Baseline lengths obtained from the first postoperative image were compared with length measurements obtained from the first interval at which they met the standard definition for migration. The conventional standards for migration using a single reference point were compared with the use of dual reference points.Results
Of the 23 patients with endograft changes, 20 were deemed to have aortic elongation rather than true migration. The remaining three patients were deemed to have migration on the basis of the IA to distal ring position compared with the IA to CA length change. The IA to CA interval length change was markedly greater in those with elongation compared with migration (23.8 ± 8.4 mm vs ?3.5 ± 5.4 mm, respectively; P < .05). The distal ring to CA interval length change was greater in patients showing elongation rather than migration (18.5 ± 6.6 mm vs ?9.8 ± 5.4 mm, respectively; P < .05). The distance between the IA and distal ring was similar for elongation and migration.Conclusions
These results highlight the dynamic changes that can occur in the aorta as a natural consequence of age. Employing two landmarks can account for these changes and proves to be an important factor, among others, in the differentiation of aortic elongation from true stent graft migration. 相似文献60.