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Background: Iodinated contrast during endovascular aneurysm repair (EVAR) is used with caution in patients with chronic kidney disease. Contrast-enhanced ultrasound (CEUS) imaging using nonnephrotoxic sulphur hexafluoride microbubble contrast is a novel imaging modality that accurately identifies and characterizes endoleaks during EVAR follow-up. We report our initial experience of using three-dimensional (3D) CEUS imaging intraoperatively as completion imaging after endograft deployment. Our aim was to compare intraoperative 3D CEUS against uniplanar angiography in the detection of endoleak, stent deformity, and renal artery perfusion during EVAR., Methods: The study enrolled 20 patients undergoing elective conventional infrarenal EVAR, after which a completion angiogram was performed and the presence of endoleak, renal artery perfusion, or device deformity were recorded. With the patient still under anesthetic, a vascular scientist blinded to angiographic findings performed 3D CEUS and reported on the same parameters., Results: Three endoleaks, one type I and two type II, were detected on uniplanar angiography and 13 endoleaks, 11 type II and two type I, were found using 3D CEUS imaging. Of note, one of these type I endoleaks was not seen on angiography, and this patient underwent balloon moulding of the neck with resolution of the endoleak on repeat imaging. Of the 11 type II endoleaks seen with 3D CEUS imaging, the inflow vessel was identified in nine cases. No graft deformity or limb kinking was seen in any patient. Both renal arteries could be visualized in 10 patients, whereas the target renal artery was seen in 11 patients. In the remaining patients, the renal arteries could not be visualized, mainly due to intra-abdominal gas or patient body habitus., Conclusions: 3D CEUS imaging detected endoleaks not seen on uniplanar digital subtraction angiography, including a clinically important type I endoleak, and was also more sensitive than 2D CEUS imaging for the detection of the source of endoleak. This technology has the potential to supplement or replace digital subtraction angiography for completion imaging to reduce the use of x-ray contrast. Intraoperative 3D CEUS has been applied to allow safe EVAR with ultralow or no iodinated contrast usage in selected cases, without compromising completion imaging., (Copyright © 2014 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Background: Varicose veins are common and increasingly are being treated by less invasive endoscopic methods such as foam sclerotherapy. Patent foramen ovale (PFO) is also common, present in approximately one-quarter of adults. PFO allows bubbles introduced by foam sclerotherapy to cross into the general circulation, potentially causing cerebral artery gas embolization with unevaluated consequences., Methods: Men and women aged 18 to 60 years with symptomatic varicose veins (CEAP C(3-5)) responded to an advertisement to recruit volunteers for a study on endovenous microfoam ablation (EMA). Participants' veins were screened by duplex ultrasound imaging, and those with isolated great saphenous vein (GSV) incompetence were tested for right-to-left (R-L) vascular shunt using transcranial Doppler (TCD) of the middle cerebral artery to detect the presence of bubble emboli after an injection of an agitated saline, blood, and air mixture as a contrast at rest and with the Valsalva maneuver., Results: Of 221 participants tested for R-L shunt, 85 (38.5%) were positive at rest (95% confidence interval [CI], 32.5-45.2) and 114 (51.8%) were positive after the Valsalva maneuver (95% CI, 45.4-58.5). A total 130 patients (58.8%) were positive for R-L shunt at rest or after Valsalva (95% CI, 52.5%-65.1%). This is significantly higher than the reported 26% prevalence of PFO in the general population (95% CI, 24.4-30.1)., Conclusions: The prevalence of R-L shunt in patients with GSV incompetence CEAP C(3-5) in this study was higher than expected in the general population. TCD does not differentiate between intracardiac shunts and intrapulmonary shunts, so this observation needs further investigation. This link between R-L shunt and varicose veins is novel and, whether etiologic or functional, may improve the understanding of both conditions. The findings have importance in the treatment of varicose veins with foam sclerotherapy and EMA., (Copyright 2010 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Objective: The objective of this study was to report current transfusion requirements and outcomes in patients undergoing elective aortic surgery with autologous transfusion., Methods: This was a retrospective review of transfusion practice in infrarenal aortic surgery in a tertiary vascular unit with a longstanding interest in autologous transfusion. One hundred and ten consecutive patients underwent infrarenal aortic surgery with a combination of acute normovolemic hemodilution (ANH) and intraoperative cell salvage (ICS). All patients underwent hemodilution to a target hemoglobin concentration of 11 g/dL and underwent ICS with a centrifugal device., Results: Median blood loss was 1140 mL (interquartile range [IQR], 683 to 1609 mL) in 78 aneurysm repairs and 775 mL (IQR, 400 to 1225 mL) in 32 aortobifemoral bypasses for occlusive disease (P =.02), resulting in a median salvaged red cell volume of 403 mL (IQR, 256 to 563 mL) for aneurysm repairs and 250 mL (IQR, 200 to 290 mL) in bypass surgery (P =.001). Thirty-six patients (33%) needed transfusion of stored blood, for a total of 115 units, with just four patients needing more than five units. The mortality rate was 8% (9/110). With multivariate analysis, low hemoglobin level (P =.006) and low platelet count (P =.023) were associated with stored blood transfusion., Conclusion: Blood loss is too small to justify ICS in surgery for occlusive disease; ANH alone may be a suitable strategy. With appropriate experience, the combination of ANH and ICS may render crossmatching unnecessary, even in aortic aneurysm surgery.

Purpose: The degree of ischemia during intermittent claudication is difficult to quantify. We evaluated calf muscle ischemia during exercise in patients with claudication with near infrared spectroscopy., Methods: A Critikon Cerebral Redox Model 2001 (Johnson & Johnson Medical, Newport, Gwent, United Kingdom) was used to measure calf muscle deoxygenated hemoglobin (HHb), oxygenated hemoglobin (O(2)Hb), and total hemoglobin levels and oxygenation index (HbD; HbD = O(2)Hb - HHb) in 16 patients with claudication and in 14 control subjects before, during, and after walking on a treadmill for 1 minute (submaximal exercise). These measures were repeated after a second maximal exercise in patients with claudication and after 7 minutes walking in control subjects. Near-infrared spectroscopy readings during maximal exercise were then compared with a model of total ischemia induced with tourniquet in 16 young control subjects., Results: Total hemoglobin level changed little during exercise in both patients with claudication and control subjects. HHb levels rose, and O(2)Hb level and HbD falls were more pronounced in patients with claudication than in control subjects after submaximal and maximal exercise. During maximal exercise, HbD fell markedly by a median (interquartile range) of 210.5 micromol/cm (108.2 to 337.0 micromol/cm) in patients with claudication compared with 66.0 micromol/cm (44.0 to 101.0 micromol/cm) in elderly control subjects and 41.0 micromol/cm (36.0 to 65.0 micromol/cm) in young control subjects (P <.001). This fall also was greater than the HbD fall induced with tourniquet ischemia at 90.8 micromol/cm (57.6 to 126.2 micromol/cm; P =.006)., Conclusion: Hemoglobin desaturation in exercising calf muscle is profound in patients with claudication, considerably greater even than that induced with three minutes of tourniquet occlusion. Further studies are necessary to investigate the relationship between the inflammatory response and near-infrared spectroscopy during exercise in patients with claudication.

Purpose: In the presence of carotid occlusion, the external carotid artery (ECA) becomes an important source of cerebral blood flow, especially if the circle of Willis is incomplete. The contribution of the ECA to hemispheric blood flow in patients with severe ipsilateral carotid stenosis has never been previously investigated., Methods: One hundred eight patients were monitored during sequential cross-clamping of the external (ECA) and then ipsilateral internal carotid artery (ICA) during carotid endarterectomy using transcranial Doppler sonography (TCD) (Neuroguard CDS, Los Angeles, Calif), to measure middle cerebral artery blood flow velocity, and near-infrared spectroscopy, to measure regional cerebral oxygen saturation (CsO(2)) (Invos 3100A; Somanetics, Troy, Mich)., Results: On the ipsilateral ECA cross-clamp, the median fall in CsO(2) was 3% (interquartile range, 1%-4%; P <.0001). On addition of the ICA cross-clamp there was a further fall of 3% and a total fall of 6% (3%-9%; P <.0001). The median percentage fall in middle cerebral artery blood flow velocity on ECA clamping was 12% (4%-24%; P <.0001); on ICA clamping it was 48% (25%-74%; P <.0001). Falls in TCD on ECA clamping were greater with increasing severity of ipsilateral ICA stenosis. The correlation between CsO(2) and TCD on external clamping, although less strong than that on internal clamping, was statistically significant r = 0.32; P =.01; Spearman rank correlation)., Conclusions: The falls in TCD and CsO(2) were of a similar order of magnitude and must therefore reflect a fall in cerebral perfusion. The ipsilateral ECA contributes significantly to intracranial blood flow and oxygen saturation in severe carotid stenosis.

Purpose: The purpose of this study was to assess the outcome after the shortening and reimplantation of tortuous internal carotid arteries to prevent kinking after endarterectomy., Methods: Through a review of prospective records, we studied patients who underwent carotid endarterectomy (CEA) (n = 233) between 1993 and 1996 who had symptomatic stenosis of the internal carotid artery (ICA) of more than 70%. An elongated proximal ICA was excised, and the ICA was reimplanted into the bifurcation in 30 (13%) patients, with additional patch angioplasty in 5 patients. Of the remaining 203 patients, 50 (21%) had Dacron patch angioplasty, and the rest had conventional CEA with simple closure., Results: In the reimplanted group, one patient had a minor stroke with complete recovery on discharge. Three patients (10%) had neck hematomas requiring reexploration, but in none of these was the bleeding from the artery. At mean follow-up of 15 months, 93% of the arteries were widely patent. Significant stenosis secondary to neointimal hyperplasia was detected in only two patients, for a restenosis rate of 6.7%, which is in line with other published reports. In the control group, 8 (3.9%) patients had perioperative transient ischemic attacks, 5 (2.5%) had strokes, and 13 (6.4%) had hematomas requiring evacuation. At follow-up, 14 (6.9%) of the arteries had restenosed., Conclusion: In carotid surgery, reconstructive techniques must be tailored to operative findings. Excision of a tortuous elongated proximal ICA with reimplantation is not associated with additional mortality or morbidity rates over those of conventional CEA alone and has the advantage of removing disease at the bifurcation. This procedure was carried out in 13% of our patients and should be a procedure with which the vascular surgeon is familiar.