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951.

Objective

The objective of this study was to describe the polar orientation of renal chimney grafts within the proximal seal zone and to determine whether graft orientation is associated with early type IA endoleak or renal graft compression after chimney endovascular aneurysm repair (ch-EVAR).

Methods

Patients who underwent ch-EVAR with at least one renal chimney graft from 2009 to 2015 were included in this analysis. Centerline three-dimensional reconstructions were used to analyze postoperative computed tomography scans. The 12-o'clock polar position was set at the takeoff of the superior mesenteric artery. Relative polar positions of chimney grafts were recorded at the level of the renal artery ostium, at the mid-seal zone, and at the proximal edge of the graft fabric. Early type IA endoleaks were defined as evidence of a perigraft flow channel within the proximal seal zone.

Results

There were 62 consecutive patients who underwent ch-EVAR (35 double renal, 27 single renal) for juxtarenal abdominal aortic aneurysms with a mean follow-up of 31.2 months; 18 (29%) early type IA “gutter” endoleaks were identified. During follow-up, the majority of these (n = 13; 72%) resolved without intervention, whereas two patients required reintervention (3.3%). Estimated renal graft patency was 88.9% at 60 months. Left renal chimney grafts were most commonly at the 3-o'clock position (51.1%) at the ostium, traversing posteriorly to the 5- to 7-o'clock positions (55.5%) at the fabric edge. Right renal chimney grafts started most commonly at the 9-o'clock position (n = 17; 33.3%) and tended to traverse both anteriorly (11 to 1 o'clock; 39.2%) and posteriorly (5 to 7 o'clock; 29.4%) at the fabric edge. In the polar plane, the majority of renal chimney grafts (n = 83; 85.6%) traversed <90 degrees before reaching the proximal fabric edge. Grafts that traversed >90 degrees were independently associated with early type IA endoleaks (odds ratio, 11.5; 95% confidence interval, 2.1-64.8) even after controlling for other device and anatomic variables. Polar orientation of the chimney grafts was not associated with graft kinking or compression (P = .38) or occlusion (P = .10). Takeoff angle of the renal arteries was the most significant predictor of chimney graft orientation. Caudally directed arteries (takeoff angle >30 degrees) were less likely to have implanted chimney grafts that traversed >90 degrees in polar angle (odds ratio, 0.09; 95% confidence interval, 0.01-0.55).

Conclusions

Renal chimney grafts vary considerably in both starting position and their polar trajectory within the proximal seal zone. Grafts that traverse >90 degrees in polar angle within the seal zone may be at increased risk of early type IA endoleaks and require more frequent imaging surveillance. Caudally directed renal arteries result in a more favorable polar geometry (eg, cranial-caudal orientation) with respect to endoleak risk and thus are more ideal candidates for parallel graft strategies.  相似文献   
952.

Objective

The objective of this study was to summarize the literature regarding the effects of renin-angiotensin system blockade (RASB) using angiotensin-converting enzyme inhibitors (ACEis) or angiotensin receptor blockers (ARBs) on human abdominal aortic aneurysm (AAA) growth, rupture, and perioperative mortality.

Methods

We conducted a systematic review in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Our review protocol was registered at the International Prospective Register of Systematic Reviews (CRD42016054082). We searched the Cochrane Central Register of Controlled Trials database, MEDLINE, and Embase from inception to 2017 for studies examining the effects of ACEi or ARB treatment on AAA growth, rupture, or perioperative mortality. Review, abstraction, and quality assessment were conducted in duplicate, and a third author resolved discrepancies. We assessed study quality using the Cochrane and Newcastle-Ottawa scales. We used random-effects models to calculate pooled mean differences and odds ratios (ORs) with 95% confidence intervals (CIs). Heterogeneity was quantified using the I2 statistic.

Results

Our search yielded 525 articles. One randomized and seven observational studies involving 35,448 patients were included. Inter-rater agreement was excellent (κ = 0.78), and risk of bias was low to moderate. All studies investigated ACEis, three studies investigated ARBs, and two studies included a composite RASB group consisting of ACEi or ARB users. Five studies assessed AAA growth, two assessed rupture rate, and one reported 30-day mortality after elective open repair. There was no difference in AAA growth rate between RASB and control (mean difference, 0.03 mm/y; 95% CI, ?0.40 to 0.46; P = .88; I2 = 60%). No protective effect of RASB (OR, 0.92; 95% CI, 0.72, 1.16; P = .47; I2 = 90%) was demonstrated for AAA rupture. Finally, RASB increased 30-day mortality in patients undergoing elective open AAA repair (OR, 5; 95% CI, 1.4, 27) according to a single well-adjusted study.

Conclusions

RASB does not appear to affect AAA growth and rupture rate but increases elective perioperative mortality. The small number of heterogeneous, retrospective studies and limited long-term follow-up preclude a definitive dismissal of RASB as pharmacotherapy for AAA. Prospective, long-term data are needed to clarify the effect of RASB on AAA growth, rupture, and perioperative mortality.  相似文献   
953.

Objective

Chronic lower extremity ischemia in pediatric patients is uncommon. The intent of this study was to better define the arterial reconstructive options and their long-term durability in preadolescent and adolescent children having clinically relevant arterial occlusions affecting the lower extremity.

Methods

The medical records of 33 consecutive pediatric patients who underwent lower extremity revascularization for chronic ischemia at the University of Michigan from 1974 to 2016 were reviewed. Patients were categorized by age, clinical manifestation, surgical intervention undertaken, and outcomes.

Results

Operative treatments involved 26 preadolescent children (mean age, 6.1 years; range, 3-9 years) and 7 adolescent children (mean age, 13.9 years; range, 10-17 years). Occlusions were due to earlier injury related to catheter (14), cannula (2), or both catheter and cannula (14); penetrating trauma (2); and vasculitis (1). Preoperative manifestations included symptomatic extremity ischemia (25), growth retardation manifested by documented limb length discrepancies (21), and scoliosis (5). Primary arterial reconstructions were delayed after the precipitating vascular event an average of 5.3 and 11.2 years in the preadolescent and adolescent children, respectively. Primary procedures involved revascularizations of 36 extremities (in preadolescents and adolescents) including autologous vein (26/5), polyethylene terephthalate (Dacron; 1/0), and expanded polytetrafluoroethylene (0/3) bypasses and vein patch angioplasty (0/1). Vein grafts traversing the abdominal cavity (15) were wrapped with a synthetic mesh. Excluding one early graft occlusion, there were no major early postoperative complications after the primary procedures. Secondary operations followed 31% of the primary operations, being performed an average of 8.8 and 6.7 years later (in 8 preadolescent and 3 adolescent children, respectively) for late graft occlusions (6), graft stenoses (3), aneurysmal vein grafts (2), and anastomotic pseudoaneurysm (1). The unassisted primary graft patency rate was 69%, and the assisted secondary graft patency rate was 94%. Symptomatic ischemia resolved in all but two children. Mean postoperative ankle-brachial indices improved to 1.08 from 0.76 preoperatively. Among children having postoperative documentation of limb lengths, the limb length discrepancies became less (11), were unchanged (1), or progressed (3). Follow-up averaged 8.0 years. There was no operative mortality in this experience.

Conclusions

Primary lower extremity arterial reconstructions in children with chronic lower extremity ischemia can be successfully undertaken with excellent results. Nevertheless, the potential for late primary graft failures, evident in nearly a third of this experience, mandates careful long-term follow-up and may necessitate secondary interventions to maintain satisfactory outcomes.  相似文献   
954.
Endovascular intervention has become the mainstay for treatment of most patients suffering from peripheral vascular disease. We describe a patient with a known nickel allergy who underwent placement of a stainless steel stent for aortoiliac occlusive disease. Despite our attempt to avoid a nickel-containing stent, the patient developed a diffuse rash consistent with a nickel or metal allergy. A review of stainless steel metallurgy revealed that nickel, cobalt, and titanium are frequently used to provide anticorrosive properties to stainless steel. The clinical significance of the use of nickel-alloy stents in the setting of patients with a nickel allergy is discussed.  相似文献   
955.

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   
956.

Objective

The objective of this study was to conduct a prospective clinical trial evaluating the technical feasibility and short-term clinical outcome of the blind pushing technique for placement of pretrimmed peripherally inserted central catheters (PICCs) through brachial vein access.

Methods

Patients requiring PICC placement at any of the three participating institutions were prospectively enrolled between January and December 2016. The review boards of all participating institutions approved this study, and informed consent was obtained from all patients. PICC placement was performed using the blind pushing technique and primary brachial vein access. The following data were collected from unified case report forms: access vein, obstacles during PICC advancement, procedure time, and postprocedural complications.

Results

During the 12-month study period, 1380 PICCs were placed in 1043 patients. Of these, 1092 PICCs placed in 837 patients were enrolled, with 834 PICCs (76%) and 258 PICCs (34%) placed through brachial vein and nonbrachial vein access, respectively. In both arms, obstacles were most commonly noted in the subclavian veins (n = 220) and axillary veins (n = 94). Successful puncture of the access vein was achieved at first try in 1028 PICCs (94%). The technical success rate was 99%, with 1055 PICCs (97%) placed within 120 seconds of procedure time and 1088 PICCs (99%) having the tip located at the ideal position. Follow-up Doppler ultrasound detected catheter-associated upper extremity deep venous thrombosis (UEDVT) for 18 PICCs in 16 patients and late symptomatic UEDVT for 16 PICCs in 16 patients (3.1%). Catheter-associated UEDVT was noted for 28 PICCs (82%) and 6 PICCs (18%) placed through brachial vein and nonbrachial vein access, respectively. The incidence of obstacles and the procedure time (<120 seconds) differed significantly between brachial vein and nonbrachial vein access (P = .001). There was no statistically significant difference between brachial vein and nonbrachial vein access in the incidence of UEDVT (odds ratio, 0.68; 95% confidence interval, 0.59-3.52; P = .22).

Conclusions

The placement of pretrimmed PICCs by the blind pushing technique and primary brachial vein access is technically feasible and may represent an alternative to the conventional PICC placement technique, having low incidences of UEDVT and other complications, with no significant difference in outcomes between brachial vein and nonbrachial vein access.  相似文献   
957.

Objective

The aim of the study was to provide, by means of computational fluid dynamics, a comparative analysis after carotid endarterectomy (CEA) between patch graft (PG) and primary closure (PC) techniques performed in real carotid geometries to identify disturbed flow conditions potentially involved in the development of restenosis.

Methods

Eight carotid geometries in seven asymptomatic patients who underwent CEA were analyzed. In six cases (A-F), CEA was performed using PG closure; in two cases (G and H), PC was performed. Three-dimensional carotid geometries, derived from postoperative magnetic resonance angiography, were reconstructed, and a computational fluid dynamics analysis was performed. A virtual scenario with PC closure was designed in patients in whom PG was originally inserted and vice versa. This allowed us to compare for each patient hemodynamic effects in the PG and PC scenarios in terms of oscillatory shear index (OSI) and relative residence time (RRT), considered indicators of disturbed flow.

Results

For the six original PG cases, the mean averaged-in-space OSI was 0.07 ± 0.01 for PG and 0.03 ± 0.02 for virtual-PC (difference, 0.04 ± 0.01; P = .0016). The mean of the percentage of area (%A) with OSI >0.2 resulted in 10.08% ± 3.38% for PG and 3.80% ± 3.22% for virtual-PC (difference, 6.28 ± 1.91; P = .008). For the same cases, the mean of the averaged-in-space RRT resulted in 5.48 ± 3.40 1/Pa for PG and 2.62 ± 1.12 1/Pa for virtual-PC (difference, 2.87 ± 1.46; P = .097). The mean of %A RRT >4.0 1/Pa resulted in 26.53% ± 12.98% for PG and 9.95% ± 6.53% for virtual-PC (difference, 16.58 ± 5.93; P = .025). For the two original PC cases, the averaged-in-space OSIs were 0.02 and 0.04 for PC and 0.03 and 0.02 for virtual-PG; the %A OSIs >0.2 were 0.9% and 7.6% for PC and 3.0% and 2.2% for virtual-PG; the averaged-in-space RRTs were 1.8 and 2.0 1/Pa for PC and 2.9 and 1.9 1/Pa for virtual-PG; the %A RRTs >4.0 1/Pa were 6.8% and 9.8% for PC and 9.4% and 6.2% for virtual-PG. These results revealed generally higher disturbed flows in the PG configurations with respect to the PC ones.

Conclusions

OSI and RRT values were generally higher in PG cases with respect to PC, especially for high carotids or when the arteriotomy is mainly at the bulb region. Thus, an elective use of patch should be considered to prevent disturbed flows.  相似文献   
958.

Objective

Since thoracic endovascular aortic repair (TEVAR) received U.S. Food and Drug Administration approval for the treatment of descending thoracic aneurysms in March 2005, excellent 30-day and midterm outcomes have been described. However, data on long-term outcomes are lacking with Medicare data suggesting that TEVAR has worse late survival compared with open descending repair. As such, the purpose of this study was to examine the long-term outcomes for on-label use of TEVAR for repair of descending thoracic aneurysms.

Methods

Of 579 patients undergoing TEVAR between March 2005 and April 2016 at a single referral center for aortic surgery, 192 (33.2%) were performed for a descending thoracic aneurysm indication in accordance with the device instructions for use, including 106 fusiform (55.2%), 80 saccular (41.7%), and 6 with both saccular and fusiform (3.1%) aneurysms. All aneurysms were located distal to the left subclavian artery and proximal to the celiac axis, and hybrid procedures including arch or visceral debranching were excluded with the exception of left carotid-subclavian artery bypass. Aortic dissection and intramural hematoma as indications for TEVAR were also excluded. Primary 30-day and in-hospital outcomes included mortality, stroke, need for new permanent dialysis, and permanent paraparesis or paraplegia. Primary long-term outcomes included survival and rate of reintervention secondary to endoleak. The Kaplan-Meier method was used to estimate long-term overall and aorta-specific survivals.

Results

The mean age was 71.1 ± 10.4 years. All aneurysms in this series were degenerative in nature and no patients with a connective tissue disorder were included. The mean aortic diameter was 5.9 ± 1.5 cm at time of intervention. Rates of 30-day and in-hospital mortality, stroke, permanent dialysis, and permanent paraparesis and paraplegia were 4.7%, 2.1%, 0.5%, and 0.5%, respectively. At a mean follow-up of 69 ± 44 months (range, 3-141 months), there were 68 late deaths (35.4%), two of which were due to aortic rupture. Overall and aorta-specific survivals at 141 months (11.8 years) were 45.7% and 96.2%, respectively. Endovascular reintervention was required in 14 patients (7.3%) owing to type I (n = 10), type II (n = 2), and type III (n = 2) endoleak, all of which subsequently resolved. No patient required open reintervention for any cause.

Conclusions

Long-term (12-year) aorta-specific survival after on-label endovascular repair of degenerative descending thoracic aneurysms in nonsyndromic patients is excellent (96%) with sustained protection from rupture, and a low rate of reintervention owing to endoleak (7%). Endovascular repair should be considered the treatment of choice for this pathology.  相似文献   
959.

Objective

The objective of this study was to investigate adherence to practice guidelines for antiplatelet and statin use after postoperative myocardial infarction (POMI) and its effect on late mortality following vascular surgery in a multicenter registry.

Methods

Antiplatelet and statin use was examined in 1749 vascular surgery procedures with POMI within the Vascular Quality Initiative (VQI) from 2005 to 2015. Our primary aim was to assess cardiac medication (CM) use at discharge, defined as (1) single antiplatelet therapy (SAPT; aspirin or P2Y12 inhibitor) or dual antiplatelet therapy (DAPT; aspirin and P2Y12 inhibitor) and (2) statin therapy. Long-term mortality in patients with POMI was analyzed on the basis of discharge CM. A proportional hazards model was developed to control for factors associated with mortality. Regional differences in CM use at discharge after POMI were compared.

Results

Overall discharge CM use after POMI included aspirin (81%), P2Y12 inhibitor (38%), statin therapy (76%), and combined antiplatelet and statin (74%). At discharge, 26% of patients were not receiving combined antiplatelet and statin therapy. SAPT (50%) was more common than DAPT (35%; P < .001). Patients with POMI undergoing carotid endarterectomy were more likely to be discharged on CM (80%) compared with patients undergoing infrainguinal bypass (78%), suprainguinal bypass (72%), endovascular aneurysm repair (71%), and open abdominal aortic aneurysm repair (59%; P < .001). Patients receiving SAPT or DAPT plus statin therapy had improved survival (79%) compared with those receiving noncombination or no therapy (69%) with mean follow-up of 5.5 years and 4.9 years, respectively (log-rank, P = .001). After adjustment for covariates including preoperative medications, treatment with SAPT or DAPT plus statin at discharge was associated with lower late mortality compared with noncombination or no therapy (hazard ratio, 0.72; 95% confidence interval, 0.56-0.93; P = .01). Regional variation in CM at discharge following POMI was also observed with a range of 33% to 100% (P = .05).

Conclusions

Within the VQI, regional and procedure-specific variation exists in CM regimen after POMI following vascular surgery. Absence of combined antiplatelet and statin therapy at discharge after POMI was associated with higher late mortality and represents an area for quality improvement in the care of these patients.  相似文献   
960.

Background

Endovascular aneurysm repair of aortoiliac or iliac aneurysms is often performed with stent graft coverage of the origin of the hypogastric artery (HA) to ensure adequate distal seal. It is considered common practice to perform adjunctive coiling of the HA to prevent a type II endoleak. Our objective was to question the necessity of pre-emptive coiling by comparing the outcomes of HA coverage with and without prior coil embolization.

Methods

Data from the Endurant Stent Graft Natural Selection Global Postmarket Registry (ENGAGE), which prospectively enrolled 1263 endovascular aneurysm repair patients between March 2009 and April 2011 from multiple centers worldwide, were used for this study. We identified patients in whom the Endurant stent graft (Medtronic Vascular, Santa Rosa, Calif) covered one or both HAs and grouped them into cases in which prior HA embolization—coils or plugs—was performed (CE) and cases in which HA embolization was not performed (NE). The occurrence of covered HA-related endoleak and secondary interventions were compared between groups.

Results

In 197 patients, 225 HAs were covered. Ninety-one HAs were covered after coil embolization (CE group), and 134 HAs were covered without prior coil embolization (NE group). Both groups were similar at baseline and had comparable length of follow-up to last image (665.2 ± 321.7 days for CE patients; 641.6 ± 327.6 days for NE patients; P = .464). Importantly, both groups showed equivalent iliac morphology concerning common iliac artery proximal, mid, and distal dimensions and tortuosity, making them suitable for comparative analysis. During follow-up, HA-related endoleaks were sparse and occurred equally often in both groups (CE 5.5% vs NE 3.0%; P = .346). Secondary intervention to resolve an HA-related endoleak was performed twice in the CE group and three times in the NE group. Late non-HA-related endoleaks occurred more often in the CE group compared with the NE group, (25.0% vs 15.0%; P = .080). Secondary interventions for other reasons than HA-related endoleaks occurred in 7.5% of NE cases and 15.4% of CE cases (P = .057), mostly for occlusions in the ipsilateral iliac limb. During follow-up, 19 NE patients and 9 CE patients died, which is not significantly different (P = .225), and no deaths were related directly or indirectly to HA coverage. Also, no reports of gluteal necrosis and bowel ischemia were made.

Conclusions

This study shows that HA coverage with the Endurant endograft without prior coil embolization does not increase the incidence of endoleak or related secondary interventions. These findings together with the already available evidence suggest that omission of coil embolization may be a more resource-effective strategy whenever HA coverage is required.  相似文献   
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