The sonographic features of lymph node venous networks and flow patterns in patients with primary chronic venous disease.

BACKGROUND: Our study aims to enhance the understanding of lymph node venous networks (LNVNs) by summarising their anatomical, sonographic features, and reflux patterns. METHOD: We examined 241 legs from 141 patients with primary chronic venous disease (CVD) using duplex ultrasound. RESULTS: The findings indicated variations in the shape, size, vascularity, and echogenicity of LNVN. The superficial inguinal lymph node with reflux appeared slightly larger, exhibiting higher velocities in the hilar artery. Regarding connections, venous flow within LNVN was predominantly drained through the saphenofemoral junction (SFJ), anterior accessory great saphenous vein (AAGSV), and great saphenous vein (GSV). A significant number of LNVNs were observed to be associated with anterolateral thigh tributaries. The study also identified valve cusps within LNVN. CONCLUSION: This study revealed a 12% prevalence of primary LNVN. Understanding the anatomical and haemodynamic features of LNVN informs treatment strategies and potentially helps prevent the recurrence of varicose veins.

A snapshot of venous ultrasound examinations in Australia and New Zealand: Implications for diagnosis and management of chronic venous disease interventions.

Objective: Chronic venous disease is a common vascular condition, affecting up to 60% of the population worldwide. In Australia and New Zealand, chronic venous insufficiency ultrasound examinations are primarily performed by sonographers. This research aimed to explore how ultrasound examinations are being performed, providing insights into current practices and recommendations for quality improvement. Method: A questionnaire was distributed to capture demographics, practices of ultrasound, examination techniques, the use of nomenclature and experience of the respondents. Results: The analysis of 97 responses showed a heterogeneity in the clinical application of ultrasound. Most sonographers performed less than two scans per day within 30-45 minutes. Deep venous incompetence was routinely excluded by all respondents. The majority used standing, sitting and reverse Trendelenburg position except for a few using supine position. Manual augmentation was the preferred provocation manoeuvre. Anatomical variations at the junctional level were not adequately evaluated. Although Giacomini's vein was assessed by 80%, 57% of those did not evaluate paradoxical reflux. Seventy-five per cent routinely assessed non-saphenous reflux; however, over 50% were unfamiliar with lymph node venous networks. A significant number of out-dated venous terms were still being used. A low participation rate in continuing professional development was identified, which might be attributable to limited education and training programs. Conclusion: The study is a multi-faceted exploration that identified a need for standardized diagnostic and reporting guidelines. Our results could explain discrepancies in diagnostic findings and inconsistencies in the use of medical terminology, with implications for clinical decision making and assessment of surgical outcome.

Juxta-anastomotic stenting with aggressive angioplasty will salvage the native radiocephalic fistula for dialysis.

OBJECTIVE: This study describes our technique of aggressive angioplasty with juxta-anastomotic stenting (JXAS) in the autogenous arteriovenous fistula and reviews our outcomes with this technique in its mature form. METHODS: We developed a JXAS technique during the last 7 years. Since 2006, we have placed 135 JXASs. The study period reviews 68 consecutive JXASs placed from 2008 to 2012 using the mature technique. We retrospectively analyzed the prospectively collected data. Thirty-three fistulas received JXAS for failure to mature, and 35 were mature but inadequately dialyzing fistulas (problem fistulas). The JXAS technique involves (1) treating the JXA segment as a unit, (2) aggressive angioplasty with rupture of stenoses, and (3) placement of an uncovered nitinol stent. RESULTS: Technical success was 97%. Of the fistulas that had failed to mature, 75% were brought to maturity by 6 months and 88% by 12 months. Adequate dialysis was achieved in all 35 problem fistulas immediately postoperatively. Assisted fistula patency was 90% at 2 years and 80% at 4 years. CONCLUSIONS: JXAS is an effective technique for maturing and maintaining the wrist radiocephalic arteriovenous fistula.

Current optimal assessment and management of carotid and vertebral spontaneous and traumatic dissection.

Dissection of the internal carotid or vertebral artery has been recognized as a cause of stroke in young patients. It is disproportionate in its representation as a cause of stroke in this age group. Intimal tears, intramural hematomas, and dissection aneurysms may be the result of trauma or may occur spontaneously. Spontaneous dissection may be the result of inherent arterial weakness or in association with other predisposing factors. Clinical diagnosis is often difficult, but increased awareness and a range of modern investigations such as computerized tomography or magnetic resonance imaging may aid in diagnosis. Management options include antiplatelet therapy, anticoagulation, thrombolysis, and surgical or endovascular procedures. Prognosis is variable, and dissection may be asymptomatic but may lead to profound neurological deficit and death.

Peripheral arterial aneurysms: open or endovascular surgery?

Peripheral arterial aneurysms are uncommon; for some aneurysm types, data are limited to case reports and small case series. There is no Level A evidence in most cases to determine the choice between open or endovascular intervention. The evolution of endovascular technology has vastly improved the armamentarium available to the vascular surgeon and interventionalists in the management of these rare and unusual aneurysms. The choice of operative approach will ultimately be determined on an individual basis, dependent on the patient risk factors, and aneurysm anatomy. After consideration, some aneurysms (femoral, subclavian, carotid and ECAA) fare better with an open first approach; renal, splenic and some visceral artery aneurysms do better with an endovascular first approach. In our practice PAAs are treated with an endovascular first approach. For these rare conditions, both open and endovascular therapy will continue to work in harmony to enhance and extend the capabilities of modern surgical management.

The role of stenting the superior vena cava syndrome in patients with malignant disease.

Superior vena cava (SVC) obstruction occurs in patients with intrathoracic malignancies. Clinical symptoms can be distressing but presentation is insidious. We investigated the outcome of endovascular management for patients with SVC syndrome. We retrospectively reviewed the case histories of 17 patients (9 men) from January 2003 to June 2009. All patients had malignant disease. There were 24 interventions (2 patients with 2 interventions and 2 patients with 3 interventions). All had SVC stenosis over 90%. All patients were treated with intrathoracic angioplasty and stenting. All procedures were technically successful, and all patients had insertion of 10 to 18 mm diameter stents with symptom resolution in 16 patients. There were 2 occlusions at 1 and 6 weeks and 2 patients with restenosis (3 and 7 months). Endovascular intervention is technically feasible for SVC occlusion, relieves symptoms, and is a useful palliation measure.

Use of inferior vena cava filters in a tertiary referral centre in Australia.

INTRODUCTION: To investigate the use of inferior vena cava (IVC) filters in a tertiary referral centre, looking at indication, types of filters and, with temporary/optional filters, removal rates. METHODS: Data was collected from a prospective database of all IVC filters inserted from January 2003 to January 2007. Patients' records and radiological imaging were all reviewed. RESULTS: 66 patients (40 males) had IVC filters inserted during the study period. The median age of the male patients was 57.5 (21-79) years, and females 56 (24-81). There were 49 (74.2%) temporary/optional filters and 17 (25.8%) permanent filters. The most common indication for filter was a contraindication to anticoagulation for both permanent (64.7%) and temporary/optional filters (77.6%). In the temporary/optional filter group, 38 of 49 (77.6%) patients had documented venous thromboembolism, while in the permanent filter group, this was 14 of 17 (82.4%). Of the optional filters, 22 of 49 (45.8%) have been removed. CONCLUSION: More than half (54.2%) of temporary/optional filters were not removed and with potential for long-term complications. A protocol has now being instituted for vascular surgeons to authorize the insertion of filters and to then be responsible for ensuring their removal.

Homocysteine activates platelets in vitro.

The mechanism of thrombogenicity in hyperhomocysteinemia remains controversial. The authors investigated the association between elevated plasma homocysteine levels, platelet function, and blood coagulation. Blood was collected from healthy subjects and patients with critical limb ischemia. Basal platelet counts and platelet aggregation as well as flow cytometry were performed to assess spontaneous- and agonist-induced platelet aggregation as well as P-selectin and Glycoprotein IIb/IIIa expression at different homocysteine concentrations. Thromboelastography was performed, and platelet shape change was assessed, using a channelyzer, by measuring median platelet volume. Lactate dehydrogenase was measured, to indirectly assess red blood cell membrane integrity, after homocysteine exposure. The study results suggest that platelet activation and hypercoagulability occur after exposure to homocysteine, especially in patients with critical limb ischemia. Homocysteine concentrations of approximately 50 micromol/L appear to be the level at which these changes occur in vitro, and this effect on platelets appears to be indirect.

Platelet activation in bypass surgery for critical limb ischemia.

Platelet activation contributes to graft occlusion after bypass surgery. This study investigated platelet activation status before, during, and after bypass. Blood was taken preoperatively from patients undergoing femoro-popliteal bypass and at incision, after dissection, after ischemia, after reperfusion, 24 hours after surgery, and almost 2 years after bypass (and given aspirin or warfarin). Platelet aggregation was measured using a turbidimetric method and platelet activation with flow cytometry. Statistical analysis was performed using Mann-Whitney U and Wilcoxon's tests. Resting platelet activation was similar between controls and patients undergoing bypass. Platelet activation decreased at incision but remained highly reactive. Platelet aggregation increased after dissection and the ischemic phase but significantly decreased after reperfusion. Platelet aggregation and activation were increased at 24 hours and subsequently after bypass. Platelets in critical limb ischemia exist in the primed state and become activated by minimum stimuli. Increased platelet activation occurs after bypass grafting for critical limb ischemia despite adjunctive therapy.

All patients benefit equally from a supervised exercise program for claudication.

This study assessed the effect of gender, diabetic status, statin use, smoking, hypertension, cardiac status, and use of cilostazol on the outcome of a supervised exercise program for patients with claudication. Patient risk factors were prospectively recorded in a group of patients who had completed 1 year on a supervised exercise program. In 165 claudicant patients, maximum walking distance increased (P < .0001) from 67 meters (range, 17-196) to 122 meters (range, 43-409). Quality of life as measured by the Medical Outcome Study Short Form 36 increased (P < .0001) from a median of 78 (range, 55-110) to 99 (range, 71-154). The improvements in claudication distance, maximal walking distance, and quality of life after the exercise program were not dependent on any of the measured patient factors. Patients referred to exercise programs for claudication are a heterogenous group. Despite this, they benefit equally from such a program.

A pilot study showing an association between platelet hyperactivity and the severity of peripheral arterial disease.

Peripheral arterial disease (PAD) is a chronic fibroproliferative inflammatory condition associated with progressive vascular stenosis. We set out to determine the relationship between spontaneous stirring-induced platelet aggregation in whole blood and the severity of lower-limb PAD, represented by the ankle-brachial pressure index (ABPI). ABPI was determined pre- and post-exercise in 31 subjects (20 men and 11 women) with established PAD. Platelets counts were determined in EDTA blood (total count) and in citrated whole blood after stirring in the absence of added ADP (spontaneous aggregation) and in the presence of added ADP (ADP-induced) for 3 min at 37 degrees C. Aggregation was calculated as a percentage of the total platelet count. Spontaneous platelet aggregation showed an inverse correlation with pre-exercise ABPI (r = -0.32; P < 0.05) and ADP-induced aggregation correlated inversely with post-exercise ABPI (r = -0.34; P < 0.05). These results indicate that platelet hyperactivity is associated with increasing severity of PAD. Increased platelet aggregation may result in thromboembolic events in the affected limb.

Factors and forces influencing stent-graft migration after endovascular aortic aneurysm repair.

PURPOSE: To assess and validate the clinical features predisposing to stent-graft migration and to calculate the distal displacement forces exerted at the proximal fixation site following endovascular aortic aneurysm repair (EVAR). METHODS: Demographic, anatomical, and graft-related features from 2862 patients were analyzed in a regression model to identify variables associated with stent-graft migration, which was defined as device movement >5 mm or considered significant by the investigator. Using the principles of continuity and momentum, a mathematical model of blood flow was created. The pulse pressure, proximal aortic and distal iliac diameters, and the degree of iliac angulation were varied in the calculations, and the distal displacement force exerted at the proximal fixation site was calculated. RESULTS: Ninety-nine patients developed stent-graft migration, which was clinically relevant in 85 (3.0%). Hypertension (p=0.015), smoking (p=0.009), maximal aortic diameter (p=0.004), and distal transverse aortic diameter (p=0.03) correlated with migration in the univariate analysis, but iliac angulation did not quite achieve significance (p=0.06). On multivariate analysis, current smoking, hypertension, distal transverse aortic diameter, maximum common iliac diameter, and increasing proximal graft size were significantly associated with stent-graft migration. The mathematical model calculated the distal displacement force exerted on the proximal fixation site of the stent-graft and validated the clinical findings. The ratio of graft-diameter change from proximal aorta to distal iliac influenced the greatest increase in the displacement force. CONCLUSIONS: The mathematical model validated hypertension, aneurysm morphology, and endograft size as clinical factors significantly associated with stent-graft migration. These findings may have important implications for the choice and design of future stent-grafts.