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Background: When hemodialysis arteriovenous accesses fail, autogenous options are often limited. Non-autogenous conduit choices include bovine carotid artery xenografts (BCAG) and expanded polytetrafluoroethylene (PTFE), yet their comparative effectiveness in hemodialysis access revision remains largely unknown. Methods: A cohort study was performed from a prospectively collected institutional database from August 2010 to July 2021. All patients undergoing an arteriovenous access revision with either BCAG or PTFE were followed for up to 3 years from their index access revision. Revision was defined as graft placement to address a specific problem of an existing arteriovenous access while maintaining one or more of the key components of the original access (e.g. inflow, outflow, and cannulation zone). Outcomes were measured starting at the date of the index revision procedure. The primary outcome was loss of secondary patency at 3 years. Secondary outcomes included loss of post-intervention primary patency, rates of recurrent interventions, and 30-day complications. Pooled logistic regression was used to estimate inverse probability weighted marginal structural models for the time-to-event outcomes of interest. Results: A total of 159 patients were included in the study, and 58% received access revision with BCAG. Common indications for revision included worn out cannulation zones (32%), thrombosis (18%), outflow augmentation (16%), and inflow augmentation (13%). Estimated risk of secondary patency loss at 3 years was lower in the BCAG group (8.6%, 3.9–15.1) compared to the PTFE group (24.8%, 12.4–38.7). Patients receiving BCAG experienced a 60% decreased relative risk of secondary patency loss at 3 years (risk ratio 0.40, 0.14–0.86). Recurrent interventions occurred at similar rates in the BCAG and PTFE groups, with 1.86 (1.31–2.43) and 1.60 (1.07–2.14) interventions at 1 year, respectively (hazard ratio 1.22, 0.74–1.96). Conclusions: Under the conditions of this contemporary cohort study, use of BCAG in upper extremity hemodialysis access revision decreased access abandonment when compared to PTFE.

The restenosis rates of 5% to 15% have been reported after carotid endarterectomy (CEA). We undertook this investigation to determine whether the routine practice of carotid artery patch closure and intraoperative completion duplex ultrasonography would result in lower rates of carotid restenosis after CEA. All consecutive carotid endarterectomies performed between 2000 and 2004 at a single institution were reviewed retrospectively. Patients underwent CEA using a longitudinal arteriotomy, followed by routine patching and intraoperative completion duplex ultrasonography. Only patients with at least one postoperative duplex scan performed at a minimum of 180 days after CEA were included. During the 5-year study period, 407 consecutive carotid endarterectomies were performed, with a combined 30-day stroke and mortality rate of 2.5%; 217 patients (53%) had one or more duplex ultrasound examinations performed at least 180 days after CEA. The mean follow-up duration was 692 days. Of the patients who underwent intraoperative intervention based on the results of the completion duplex study, none experienced restenosis, stroke, or death. CEA that is performed with routine patching and intraoperative duplex completion ultrasonography is a safe, durable operation with restenosis rates below those commonly reported.

Mycotic aneurysm formation in a visceral artery carries a significant risk of mortality and morbidity. The authors present a case of a symptomatic superior mesenteric artery aneurysm secondary to a septic embolus in a patient who had undergone aortic valve replacement. The patient initially presented with evidence of acute intestinal ischemia from a presumed embolic source. Although an extensive bowel resection was performed, an adequate search for the embolus was not carried out. Prompt diagnosis and removal of suspected septic emboli must be performed to avoid the formation of delayed mycotic aneurysms.

The optimal approach to revascularization for chronic mesenteric ischemia has not been firmly established during the past three decades. The present study was undertaken to evaluate the safety and results of primary mesenteric revascularization for chronic mesenteric ischemia by transaortic endarterectomy. A descriptive retrospective analysis of 14 patients who underwent trap-door transaortic endarterectomy for primary mesenteric revascularization was performed. Clinical presentations of the patients included abdominal pain (n = 13) and weight loss (n = 7). All patients underwent preoperative aortography and subsequent elective reconstruction. Demographic features, perioperative, and long-term outcomes were analyzed. The study population consisted of 12 females and two males with a mean age of 67 years. The mean operative duration was 3 hours with an ischemic time of 33 minutes. The initial success rate of mesenteric revascularization was 93%. One early graft failure was salvaged with urgent embolectomy without bowel resection. There was no hospital mortality, but the overall postoperative morbidity rate was 50% (n = 7). Thirteen patients (93%) were discharged within 2 weeks. Late recurrent ischemia and intestinal infarction developed in one patient, requiring emergency bowel resection. Sustained relief of symptoms was achieved in 13 of 14 patients (93%). The overall survival rates were 85% ± 10.0% and 77% ± 11.7% at 1 and 3 years, respectively. Transaortic endarterectomy is a safe and effective technique for elective primary mesenteric revascularization for patients with chronic mesenteric ischemia. This approach allows simultaneous revascularization of multiple visceral arteries and achieves durable relief of symptoms.

Endoluminal repair of an infrarenal saccular aortic aneurysm was undertaken with a modular endovascular stent graft in a 74-year-old man. After deployment of the main body and right iliac limb of the graft, an attempt was made to gain guide wire access to the open short left limb of the graft for placement of the left iliac prosthesis. Attempts to gain access to the left limb graft from the left femoral artery area were unsuccessful. Since we were unable to pass the wire into the iliac system or snare it from below, can nulation from the left brachial artery was attempted. This resulted in the guide wire coiling up within the aneurysm. Eventual conversion to an open procedure confirmed that the short open left limb of the modular graft had deployed such that the opening was completely impacted against the inferior wall of the saccular aneurysm, preventing successful passage of a guide wire. The distance from the aortic neck to the base of the aneurysm is generally not considered an important parameter whe...

Population-based studies have revealed differences in the preva lence of lower extremity arterial occlusive disease between males and females. Recent studies have begun to unravel the etiology of these gender-based differ ences. Nonetheless, the morbidity of lower extremity arterial disease may be severe and is similar for both genders. Recent studies, however, have revealed gender based bias in treatment patterns for arterial disease of the lower extrem ities. This review addresses the impact of gender on the prevalence, morbidity, and management of lower extremity atherosclerosis. A critical review of the surgical literature reveals that surgical management of infrainguinal occlusive disease offers females patients the same benefits and limitations as for male patients.

The authors used an on-line, real-time, continuous blood gas monitor in 5 patients undergoing elective suprarenal aortic reconstruction. They retrospectively analyzed data to evaluate its utility in acid-base management and in detection of dynamic changes in oxygenation. Seven sets of data were analyzed since 1 patient underwent two additional periods of aortic crossclamping. A similar group of 7 patients undergoing elective suprarenal aortic surgery without continuous blood gas monitoring was analyzed and served as a control group. There was a highly significant mean decrease in partial pressure of oxygen (P02) of 158 mm Hg (P = 0.0060) with unclamping. In 1 patient the P02 dropped from 218 to 63 mm Hg within sixty seconds of unclamping, and this required immediate reinstitution of two-lung ventilation. Continuous availability of pH permitted accurate therapy with bicarbonate infusion during clamping. As a result there was no significant change in pH between preclamp and immediately after unclamping (P = 0.97). In the control group the pH decreased from a mean of 7.38 to a mean of 7.24 (P = 0.0005) between preclamp and after unclamping. In summary, dynamic changes in oxygenation and pH are observed during suprarenal aortic surgery. Continuous blood gas monitoring provided data resulting in improved management of acid-base status and early detection of significant decreases in oxygenation.

We conducted a nation-wide study of the relationship of myopia with height, weight and body-mass index in order to confirm observations that myopic persons are taller than non-myopes. From a review of the data of 106,926, consecutive male military recruits aged 17 to 19 years, we found that myopia is associated neither with higher stature nor with greater weight. Persons with severe myopia were slightly shorter (172.8 +/- 7.1 cm) and weighed less (62.6 +/- 11.0 kg) than those with mild myopia (173.3 +/- 6.9 cm and 63.8 +/- 10.5 kg respectively), while the non-myopes were taller (173.7 +/- 6.7 cm) and heavier (63.9 +/- 10.2 kg) than the myopes (p = 0.0001). The mean body-mass index was only slightly smaller among the myopes (21.1 +/- 3.1 kg/m2) than among the non-myopes (21.2 +/- 2.9 kg/m2, p = 0.0001).

Objective: In pursuing a policy of selective greater saphenous vein (GSV) preservation in the treatment of varicose veins we hypothesized that limbs with isolated tributary disease (TD) would be ideal candidates for GSV preservation. Design: Prospective blinded series. Setting: University teaching hospital. Patients: Fifty-nine symptomatic legs in 45 consecutive patients presenting with varicose veins. Interventions: Patients were evaluated by physical examination, quantitative photoplethysmography (QPG) and colour flow duplex examination. Main outcome measure: Colour flow duplex as the standard of comparison. Results: Of the limbs studied, 29% had isolated TD. The sensitivity of physical examination for GSV incompetence was 43%, but specificity was 100%. QPG yielded a similar sensitivity of 24% and specificity of 100%. Conclusions: Twenty-nine per cent of limbs were optimal candidates for sparing of the GSV with excision of branch varicosities alone. Duplex examination was necessary only when the GSV was clinically normal, and QPG was not helpful.

A 35-year-old previously well man presented with rightupper extremity digital ischemia and ulceration. Baselineblood work, including a screen for connective tissues dis-eases, was normal. A 12-lead EKG and a transthoracicechocardiogram with bubble study were also normal.Non-invasive magnetic resonance (MR) angiographydemonstrated unilateral arterial insufficiency of the righthand (Panel A-1: left hand; Panel A-2: right hand). Inva-sive angiography confirmed abnormal right hand arterialsupply with obliteration of digital arteries (Panel B-1),while the left hand was normal (not shown). An apparentstenosis (arrows) was observed in the proximal rightradial artery with the arm in the neutral position(Panel B-2), which worsened with pronation with con-comitant flow reduction (Panel B-3). Persistent contraststaining was seen in the post-stenotic region, consistentwith very low flow and a possible propensity for throm-bosis. Intravascular ultrasound (IVUS) of the apparentstenosis was performed, which demonstrated externalcompression rather than a luminal stenosis (not shown).Vascular ultrasound confirmed decreased flow with pro-nation and an aberrant brachioradialis tendon (T) thattracked over the radial artery (R) and caused compres-sion (not shown). This finding was confirmed at surgery(Panel C-1: initial anatomy), and corrected by moving theradial artery course over the tendon (Panel C-2: postoper-ative anatomy). Distal embolism was the presumedmechanism of digital ischemia, and the patient ’s ulcershealed postoperatively.Arterial entrapment more commonly occurs in thelower extremity with entrapment of the popliteal arteryby surrounding musculotendinous structures, but alsomay occur in the upper extremities as this case demon-strates. Radial artery entrapment has been reported pre-viously as a rare complication of an orthopedic injurysuch as posterior dislocation of the elbow

The authors studied the pathophysiology of hyperfusion syndrome with diffusion-weighted and perfusion-weighted magnetic resonance imaging. They identified vasogenic or cytotoxic edema by diffusion-weighted imaging, assessed cerebral artery mean flow velocities by transcranial Doppler, and assessed the relative nterhemispher c difference of cerebral blood flow by perfusion-weighted imaging. No patient presented with pathologic diffusion-weighted imaging hyperintensitities, 2 patients exhibited an MRI pattern of reversible vasogenic edema. Mean flow velocities in the middle cerebral artery were not abnormally increased. They concluded that hyperfusion syndrome can occur in the presence of moderate relative hyperfusion of the ipsilateral hemisphere and that mean fiow velocities may not accurately reflect relative interhemispheric differences.