Venous morphology predicts class of chronic venous insufficiency.
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OBJECTIVES: this study aimed to determine specific morphological differences in long saphenous veins from patients with various grades of chronic venous insufficiency. DESIGN: comparable veins from a control group were compared with patients with either primary varicose veins or those with associated skin changes including venous ulcers. MATERIALS: below-knee segments of saphenous vein were examined from a total of 64 patients. METHODS: veins were examined for elastic-tissue disruption and endothelial-cell changes and comparisons made between clinical groups. RESULTS: elastic-tissue disruption, as measured by fragmentation of the elastic lamina and the percentage of the intimal-medial boundary containing elastin, increased with increasing severity of venous disease. Moreover, endothelial cells became more densely packed, as measured by endothelial cell and endothelial-cell nuclei density, with increasing severity of disease. Other measures such as the density of multinucleated "giant" endothelial cells and the number of nuclei per "giant" cell did not correlate with venous disease, however. CONCLUSIONS: this study demonstrates that several morphological characteristics of superficial saphenous veins correlate with severity of venous disease. In particular, the alterations to the structure of elastic tissue within these veins appears indicative of the progressive nature of chronic venous insufficiency. (+info)
Reference values for vertebral artery flow volume by duplex sonography in young and elderly adults.
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BACKGROUND AND PURPOSE: Vertebrobasilar ischemia has been attributed to a reduction of net vertebral artery flow volume, the product of mean flow velocity and the cross-sectional area of the vessel. It can be determined by duplex sonography. There are no reference values for vertebral artery flow volume in an age group representative of patients with cerebrovascular disease. METHODS: We examined 50 nonvascular neurological patients (age 55.8+/-14.0 years). Flow velocities and vessel diameters were recorded in the intertransverse (V2) segments bilaterally, and the flow volume was calculated according to the following equations: (1) Q1=time-averaged mean velocity times area and (2) Q2=(time-averaged maximum velocity/2)times area. RESULTS: Flow velocities and vessel diameters tended to be lower on the right side, resulting in a lower flow volume. Flow volumes (according to Equation 1) were 77.2+/-29.8 mL/min on the right side, 105.3+/-46.4 mL/min on the left side, and 182.0+/-56.0 mL/min net. Side-to-side differences were not significant. Flow volumes calculated with the 2 equations did not differ significantly. An age dependence could not be shown, but vessel diameters and net vertebral artery flow volumes were significantly lower in women than in men. The normal range for net vertebral artery flow volume defined by the 5th to 95th percentiles is between 102.4 and 301.0 mL/min. This wide range is due to the high interindividual variability of the parameters. CONCLUSIONS: On the basis of the reference values presented here, the association of decreased vertebral artery flow volume and vertebrobasilar ischemia should be reevaluated. Additional areas for investigation include the quantification of collateral flow in the vertebral arteries in carotid artery occlusive disease and their contribution to overall cerebral blood flow volume. (+info)
Accelerated carotid artery disease after high-dose head and neck radiotherapy: is there a role for routine carotid duplex surveillance?
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PURPOSE: High-dose external radiotherapy used in the treatment of head and neck carcinoma has been implicated as a risk factor for accelerated atherosclerotic disease of the carotid arteries. However, how radiotherapy affects atherosclerotic disease is controversial, and little data exist to demonstrate a strong relationship between radiotherapy and progressive carotid disease. METHODS: We performed a retrospective chart review of 69 patients (all men) who underwent duplex ultrasound scanning examinations for carotid disease between 1993 and 1998. Twenty-three patients had received high-dose radiotherapy for the treatment of head and neck carcinoma within the past 12 years (group 1; mean age, 67.8 years), and 46 patients were randomly selected as age-matched control subjects (group 2; mean age, 68.3 years). The mean radiation dose was 6060 +/- 182 rads, and the average interval between radiotherapy and ultrasound scanning was 6. 5 +/- 1.8 years. There was no significant difference between the two groups in the presence of these comorbidities: diabetes mellitus, coronary artery disease, hypertension, tobacco use, hypercholesterolemia, peripheral vascular disease, or stroke. Similarly, there was no difference in the indications for the duplex scanning studies. RESULTS: Five of the 23 patients in group 1 (21. 7%) were found to have advanced carotid disease (70% to 99% stenosis); four patients were symptomatic, three patients went on to endarterectomy, and one patient was awaiting surgery. Two of the 46 patients in the control group (4%) had advanced carotid disease. One patient was symptomatic, and both patients underwent endarterectomy. A significant difference in the prevalence of advanced disease between the two groups was noted (P =.037). Sixteen patients who survived irradiation underwent a second duplex scanning study and had evidence of progressive disease with significant increases in peak systolic velocities. CONCLUSION: High-dose radiotherapy to the head and neck region may be a significant risk factor for accelerated carotid atherosclerotic disease. Routine carotid duplex surveillance may be warranted in this high-risk patient population. (+info)
Association of endotoxemia with carotid atherosclerosis and cardiovascular disease: prospective results from the Bruneck Study.
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OBJECTIVES: Focus of the current study was on the significance of bacterial endotoxin, which shows a variety of pro-atherogenic properties and may occur at high concentration in the circulation of infected subjects. BACKGROUND: The possibility of an infectious risk factor in atherogenesis and cardiovascular disease has stimulated research interest, but the nature of such process remains obscure. METHODS: We measured plasma endotoxin levels (LAL assay) in a random population of 516 men and women 50 to 79 years old at the 1990 baseline evaluation (Bruneck Study). End points of this prospective survey were incident (early) atherosclerosis in the carotid arteries as assessed with high-resolution Duplex ultrasound (five-year follow-up rate, 98%) and incident cardiovascular disease (follow-up rate, 100%). RESULTS: Median endotoxin concentration amounted to 14.3 pg/ml (range, 6.0 to 209.2 pg/ml). Subjects with levels beyond 50 pg/ml (90th percentile) faced a threefold risk of incident atherosclerosis (odds ratio [95% confidence interval] 2.9 [1.4-6.3]; p < 0.01). The risk associated with high endotoxin was most pronounced in subjects with chronic infections and in current and ex-smokers. Notably, smokers with low endotoxin levels and nonsmokers did not differ in their atherosclerosis risk, whereas smokers with high levels almost invariably developed new lesions. All findings emerged as independent of vascular risk factors. Similar results were obtained for incident cardiovascular disease. CONCLUSIONS: The current study yields first epidemiologic evidence that endotoxemia constitutes a strong risk factor of early atherogenesis in subjects with chronic or recurrent bacterial infections and a link in the association between cigarette smoking and atherosclerotic disease. (+info)
Serial pulsatility index measurements in renal grafts before, during, and after episodes of urinary obstruction.
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The usefulness of pulsatility index determinations for the diagnosis of obstructive collecting system dilatation was investigated in 10 renal transplant patients whose grafts developed urinary obstruction from different causes. For this purpose we compared pulsatility index values obtained (1) before the ultrasonographic detection of obstruction or baseline study, (2) 1 day before surgical repair, and (3) within 2 weeks after surgery. In 7 of 10 obstructed grafts, the pulsatility index values were increased only mildly to moderately preoperatively. In the remaining three grafts, a mild decrease in pulsatility index was observed in spite of severe collecting system dilatation. Changes in pulsatility index were not statistically significant. Impedance measurements appeared not to be useful for diagnosing obstructive collecting system dilatation. (+info)
Does a completely accomplished duplex-based surveillance prevent vein-graft failure?
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OBJECTIVES: to assess the benefits of duplex-based vein-graft surveillance over clinical surveillance with distal pressure measurements. DESIGN: prospective randomised comparative trial. MATERIAL AND METHODS: three hundred and forty-four patients with 362 consecutive infrainguinal vein bypasses were prospectively randomised to a follow-up regime with or without duplex scanning (ABI group and DD group) at 1, 3, 6, 9, and 12 months postoperatively. RESULTS: one hundred and eighty-three grafts were enrolled to the ABI group and 179 to the DD group. The primary assisted patency, secondary patency and limb salvage rates were 67%, 74%, 85% for the ABI group and 67%, 73%, 81% for the DD group. Ninety grafts in the ABI group and 57 in the DD group had surveillance that completely adhered to the protocol. The outcome was also similar for these groups at one year (77%, 87%, 94% and 77%, 83%, 93% respectively), although grafts were revised more frequently in the DD group. CONCLUSIONS: intensive surveillance with duplex scanning did not improve the results of any outcome criteria examined. To demonstrate any potential benefit of duplex scanning for vein-graft surveillance a multicentre study with a large number of patients to ensure sufficient power is needed. (+info)
Color duplex measurement of cerebral blood flow volume in healthy adults.
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BACKGROUND AND PURPOSE: Global cerebral blood flow (CBF) is an important yet largely unknown quantity in the treatment of neurological intensive care patients. Color duplex sonography of the extracranial cerebral arteries can be used to measure global CBF volume directly at the bedside. To establish reference data on global CBF volume and to test the influence of sex and age on this parameter, a prospective study was performed in a group of 78 healthy adults aged 20 to 85 years (39 women, 39 men; mean age, 52+/-19 years in either sex). METHODS: The common, external, and internal carotid arteries and the vertebral arteries were examined with the use of a 7.0-MHz transducer of a computed sonography system. Angle-corrected time-averaged flow velocity and the diameter of the vessel were measured. Intravascular flow volumes were calculated as the product of angle-corrected time-averaged flow velocity and the cross-sectional area of the circular vessel. CBF volume was determined as the sum of flow volumes in the internal carotid and vertebral arteries of both sides. RESULTS: From 20 to 85 years of age, CBF volume decreased significantly (P+info)
Macrovascular disease and systemic sclerosis.
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OBJECTIVE: To determine if macrovascular disease is more prevalent in systemic sclerosis (SSc) compared with unaffected subjects. METHODS: 54 patients with SSc (both limited and diffuse disease) and 43 unaffected control subjects of similar age and sex were recruited. All subjects underwent a basic screen for conventional atherosclerotic disease risk factors. All had non-invasive vascular assessments-that is, carotid duplex scanning and measurement of ankle brachial blood pressure index-to identify the presence of asymptomatic peripheral vascular disease. RESULTS: 33 of 52 (64%) patients had carotid artery disease compared with only 15 of 42 (35%) controls (p=0.007). Eleven (21%) of these patients had moderate disease compared with only two (5%) controls (NS). Nine of 53 (17%) SSc patients had evidence of peripheral arterial disease compared with no controls. This result was also statistically significant (p=0.003). There were no significant differences in the basic risk factor profile, which included cigarette smoking, systolic and diastolic blood pressure, cholesterol, trigyceride and glucose concentrations. CONCLUSION: Macrovascular disease is more common in SSc. Screening of these patients may allow identification of "at risk" patients at an early stage and allow the study of treatments to attenuate the high rate of cardiovascular mortality in these patients. (+info)