Acute problems of hemodialysis access: Thrombosis, aneurysms, symptomatic high-flow fistulas, and complications related to central lines.

Hemodynamic complications frequently affect vascular access and are important causes of morbidity and mortality. We present a review of acute complications affecting vascular accesses, focusing on classical and new treatments. Acute complications in hemodialysis vascular access are often underestimated and undertreated, and can present a challenge for both vascular surgeons and anesthesiologists. Accordingly, we considered different anesthesiologic approaches to both hemorrhagic and nonhemorrhagic patients. A strict collaboration among nephrologists, surgeons, and anesthesiologists can potentially improve prevention and management of acute complications and quality of life.

A morphovolumetric analysis of aneurysm sac evolution after elective endovascular abdominal aortic repair.

OBJECTIVE: Abdominal aortic aneurysm (AAA) sac shrinkage after endovascular aortic repair (EVAR) has been regarded as positive marker of EVAR success durability. The purpose of this study was to describe the morphovolumetric changes of the AAA sac during follow-up after elective EVAR and to analyze sac shrinkage-related variables. METHODS: This is a single-center, retrospective, observational cohort study from a tertiary referral university hospital. All patients treated with EVAR between January 2013 and December 2018 were identified. Inclusion criteria were elective EVAR for AAA, preoperative computed tomography angiography within 6 months before EVAR and at least one postoperative computed tomography angiography during the follow-up, using a standardized protocol. Aneurysm sac shrinkage was defined as diameter decrease of 1 cm or more, volume shrinkage threshold was identified by a 16% decrease compared with the preoperative value. Primary outcomes were early (≤30 days) and late survival, and freedom from aneurysm-related mortality (ARM), and aortic reintervention. RESULTS: There were 149 of the 325 patients (45.8%) who met the inclusion criteria: 133 (89.3%) were male and 16 (10.7%) female. The mean age was 74 ± 7 years (range, 55-87 years); the median AAA diameter was 56 mm (interquartile range, 50.0-61.2 mm) and the median volume was 138.8 cm3 (range, 99.0-178.3 cm3). Primary technical success was achieved in 145 patients (97.3%). The in-hospital mortality rate was 1.3%. The median follow-up was 42 months (interquartile range, 22.5-58.0 months). Both AAA diameter and volume decreased (P = .001 and P = .035, respectively) compared with preoperative measurements. Diameter shrinkage was adjudicated in 27 patients (18.1%), volume shrinkage was observed in 42 patients (28.2%). A Cox regression analysis demonstrated an association between the AAA diameter shrinkage and the preoperative diameter (P = .002; hazard ratio, 1.03; 95% confidence interval [CI], 1.011-1.052). The presence of a persistent endoleak predicted the absence of volume shrinkage (P = .001; hazard ratio, 7.75; 95% CI, 2.282-26.291). The estimated freedom from ARM was 97.5 ± 1.0% (95% CI, 93-99) at 12 months, and 96 ± 2% (95% CI, 90-98) at both 36 and 60 months. Aortic reintervention during the follow-up period was necessary in 7 patients (4.7%). ARM was only observed in the group characterized by the concomitant absence of diameter and volume shrinkage. CONCLUSIONS: Volumetric analysis showed to have higher sensitivity than the simple two-dimensional measurement of the diameter to study AAA sac changes after EVAR. Although no predictor was found to be associated with AAA volume shrinkage, ARM occurred only in the group of AAAs with the absence of volume shrinkage.

Transposition of the left vertebral artery during endovascular stent-graft repair of the aortic arch.

OBJECTIVES: The aim of this study was to present our experience with the management of isolated left vertebral artery during hybrid aortic arch repairs with thoracic endovascular aortic repair completion. METHODS: This is a single-center, observational, cohort study. Between January 2007 and December 2018, 9 patients (4.5%) of 200 who underwent thoracic endovascular aortic repair were identified with isolated left vertebral artery. The isolated left vertebral artery was the dominant vertebral artery in 4 cases and entered the Circle of Willis to form the basilar artery in all cases. Isolated left vertebral artery transposition was performed in 2 patients during open ascending/arch repair before thoracic endovascular aortic repair completion. In 4 patients, isolated left vertebral artery transposition was performed concomitant with carotid-subclavian bypass during thoracic endovascular aortic repair completion ("zone 2" thoracic endovascular aortic repair). Primary outcomes were early (<30 days) and late survival, freedom from aortic-related mortality, and isolated left vertebral artery patency. RESULTS: Primary technical success was achieved in all cases. Isolated left vertebral artery-related complication occurred in 1 patient (Horner syndrome). Immediate thrombosis, vagus/recurrent laryngeal nerve palsy, lymphocele, and chylothorax were never observed. Postoperative cerebrovascular accident or spinal cord injury was not observed. Median follow-up was 15 months (range, 3-72). We did not observe aortic-related mortality during the follow-up. Aortic-related intervention was never required. Both isolated left vertebral artery and carotid-subclavian bypass are still patent in all patients with no sign of anastomotic pseudoaneurysm or stenosis. CONCLUSIONS: Although isolated left vertebral artery is not a frequent occurrence, it is not so rare. It may pose additional difficulties during hybrid aortic arch surgical repairs, but isolated left vertebral artery transposition was feasible, safe, and a durable reconstruction.

Arch and access vessel complications in penetrating aortic ulcer managed with thoracic endovascular aortic repair.

BACKGROUND: To analyze our experience and to describe access and arch-related challenges when performing thoracic endovascular aortic repair (TEVAR) for penetrating aortic ulcers (PAUs). METHODS: This is a single-center, observational, cohort study. Between October 2003 and February 2019, 48 patients with PAU were identified; 37 (77.1%) treated with TEVAR were retrospectively analyzed. Primary major outcomes were early (<30 days) and late survival, freedom from aortic-related mortality (ARM), and a composite endpoint of arch/vascular access-related complications. RESULTS: On admission, 17 (45.9%) patients were symptomatic with 4 (10.8%) presenting with rupture. In-hospital mortality was 8.1% (n=3). We observed 10 (27.0%) arch/access-related complications. There were 4 (10.8%) arch issues: 2 transient ischemic attacks and 2 retrograde acute type A dissections which required emergent open conversion for definitive repair. Access issues occurred in 6 (16.2%) patients: 3 (8.1%) required common iliac artery conduit, and 1 (2.7%) patient required iliac artery angioplasty to deliver the stent-graft. In addition, 2 (5.4%) patients developed access complications which required operative repair [femoral patch angioplasty (n=2), and femoral pseudoaneurysmectomy (n=1)]. Arch/access-related mortality rate was 5.4% (n=2) and median follow-up was 24 (range, 1-156; IQR, 3-52) months. Estimated survival was 87.1% (standard error: 0.6; 95% CI: 71.2-84.9%) at 1 year, and 63.3% (SE: 0.9; 95% CI: 44.1-79%) at 4 years. Estimated freedom from reintervention was 88.9% (SE: 0.5; 95% CI: 74.8-95.6%) at 1 year, and 84.2% (SE: 0.7; 95% CI: 67.3-93.2%) at 4 years. No arch/access-related issues developed during the follow-up period. CONCLUSIONS: Our experience confirms that vascular access and aortic arch issues are still a challenging aspect of performing TEVAR for PAUs. Our cumulative 27% rate of access/arch issues is lower than previously reported due to both technological advancements and meticulous management of both access routes and arch anatomy.

Carotid artery stenting renaissance: is it safe and effective using new materials?

Data from randomized controlled trials (RCTs) demonstrated significant differences between carotid artery stenting (CAS) and carotid endarterectomy (CEA) in terms of early neurological outcomes (from 0 to 30 days), although mid- and long-term neurological results are indistinguishable. CAS in symptomatic standard risk patients is coupled with a higher risk of any stroke, and death or any stroke at 30 days, while the rates of disabling or major stroke do not vary remarkably between treatments. Since the micro-embolization through the stent struts is the primary suspected cause of suspected early postoperative neurological complications (i.e., non-disabling stroke), surgical technology has focused on the production of a new generation of stents with a double layer of mesh to reduce the "free area" of the cells, and on new cerebral protection devices. Another major determinant of early negative outcomes is believed to be the intraluminal manipulation occurring during carotid engagement from the aortic arch, the crossing maneuvers at the level of the culprit lesion and vessel trauma during angioplasty. To address these subject matters, new embolic protection devices and innovative strategies have been developed, consequently. This review is designed to furnish the current status of CAS results, to update the ongoing RCTs comparing CAS vs. CEA outcomes, and to recapitulate the features and clinical outcomes for a new carotid stent design, the so called "mesh-stents", and new embolic protection tools.