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L Norgren

Publications and source records attributed to L Norgren.

At least 37 records · Page 2Linked to original sources
PubMed2003

Peripheral arterial disease. Contrast-enhanced 3D MR angiography of the lower leg and foot compared with conventional angiography.

PURPOSE: To determine whether contrast-enhanced 3D MR angiography (CE MRA) could replace digital subtraction angiography (DSA) for the evaluation of atherosclerotic peripheral vascular disease of the lower leg and foot. MATERIAL AND METHODS: Thirty-five patients with symptoms of atherosclerotic disease of the leg were examined prospectively with CE MRA of the foot and the lower legs as well as with DSA from the aorta to the pedal arches. The MRA technique was focused on optimal imaging of the arteries of the foot. RESULTS: The agreement between CE MRA and DSA for grading of stenosis was moderate to good (weighted kappa-values 0.48-0.80). The sensitivity of CE MRA for detection of significant stenosis (> or = 50%) was 92% and the specificity was 64% with DSA as gold standard. CONCLUSION: CE MRA is a fairly accurate method for the demonstration of atherosclerotic disease below the knee including the pedal arches. It can replace DSA for the assessment of distal arteries in patients with impaired renal function. However, image quality and resolution still needs to be improved before CE MRA can become the method of choice in all patients.

Aged↗
PubMed2003

Costs in follow-up of endovascularly repaired abdominal aortic aneurysms. Magnetic resonance imaging with MR angiography versus EUROSTAR protocols.

AIM: Endovascular repair of abdominal aortic aneurysms (AAA) necessitates a long-term follow-up. These patients are often old and renal insufficiency is not unusual. Cost-effectiveness needs to be addressed in evaluating methods of follow-up. The aim of this study was to compare costs of 5 years follow-up with magnetic resonance imaging with contrast enhanced three-dimensional magnetic resonance angiography (MRI/MRA) with follow-up using CT with DSA, or CTA. We also assessed the impact of contrast media induced (CMI) nephropathy on follow-up costs. METHODS: We have implemented Swedish costs of CT with DSA, and CTA on the reported follow-up examinations from the EUROSTAR progress report 2000. The costs of follow-up with CT with DSA, or CTA were compared to a follow-up protocol with MRI/MRA. A cost analysis including a risk analysis of CMI nephropathy was made between MRI/MRA and CT with DSA, or CTA. RESULTS: Excluding the risk of CMI nephropathy, the 5 years follow-up cost in Euro ( ) with MRI/MRA ( 5715) is substantially higher than CT with DSA ( 3 095) or CTA ( 3573). The cost analysis favours MRI/MRA if the risk of CMI nephropathy from CT with DSA, or CTA is more than 5%. CONCLUSION: MRI/MRA can be cost-effective for follow-up of endovascularly repaired AAA depending on the risk of CMI nephropathy for CT with DSA, and CTA. MRI/MRA should be the method of choice for patients with pre-existing renal insufficiency.

Aged↗
PubMed2003

Global venous function correlates better than duplex derived reflux to clinical class in the evaluation of chronic venous disease.

AIM: To compare the symptoms and signs of patients with chronic venous disease with the objective results of duplex ultrasound and plethysmography (foot volumetry). METHODS: One hundred and one patients with symptomatic chronic venous disease were investigated with duplex ultrasound and foot volumetry. Patients were classified according to the CEAP classification and the symptoms of pain, heaviness, tiredness, ankle swelling and night cramps were graded. The severity of the disease was judged objectively by the reflux time (sum of reflux time at 6 levels) and the venous function was measured globally with expelled volume (ml) and refilling rate (Q) (ml/100 mlxmin) after exercise, and expelled volume related to foot volume (EVrel), (ml/100 ml). The ratio Q/EVrel)was calculated. Correlation was calculated between clinical class, symptoms and objective parameters. RESULTS: The correlation analyses showed a clear constant relationship between the CEAP clinical classification and the foot volumetry measures (Q/EVrel), r=0.48; p<0.01) There was no such relationship between clinical class and the sum of duplex calculated reflux time (r=-0.05), or between foot volumetry and reflux time. There was no correlation between the clinical class and the total score of symptoms (r=0.044). CONCLUSION: The clinical class of CEAP classification correlates significantly with foot volumetry parameters. There is no correlation between clinical class and reflux time. The severity of the venous disorder and subsequently the need for treatment is more accurately judged by foot volumetry as a global measure. Clinical classification has a realistic meaning concerning the functional evaluation of venous disease.

Adult↗
PubMed2003

A clinical approach to the management of a patient with suspected renovascular disease who presents with leg ischemia.

Atherosclerotic renal artery stenosis (ARAS) may cause hypertension, progressive renal failure, and recurrent pulmonary edema. It typically occurs in high risk patients with coexistent vascular disease elsewhere. Most patients with ARAS are likely to die from coronary heart disease or stroke before end-stage renal failure occurs. Recent controlled trials have shown that most patients undergoing angioplasty to treat renovascular hypertension still need antihypertensive agents 6 or 12 months after the procedure. Nevertheless, the number of antihypertensive agents required to control blood pressure adequately is lower following angioplasty than for medication alone. Trials assessing the value of revascularization for preserving renal function or preventing clinical events are only in the early recruitment phase. Revascularization should be undertaken in patients with ARAS and resistant hypertension or heart failure, and probably in those with rapidly deteriorating renal function or with an increase in plasma creatinine levels during angiotensin-converting enzyme inhibition. With or without revascularization, medical therapy using antihypertensive, hypolipidemic and antiplatelet agents is necessary in almost all cases.

Humans↗
PubMed2003

Patient preferences for follow-up methods after endovascular repair of abdominal aortic aneurysms.

AIM: A fundamental and influential difference between open and endovascular repair of abdominal aortic aneurysms is the central role of imaging after endovascular repair. Willingness of the patient to return for further imaging is an important factor in choosing the method for follow-up. This study was undertaken to assess the subjective experiences of patients undergoing magnetic resonance imaging with contrast enhanced MR angiography, computed tomography and angiography (DSA) after endovascular repair of abdominal aortic aneurysms. METHODS: In a prospective study, 24 consecutive patients after endovascular repair of abdominal aortic aneurysms were invited to answer a questionnaire to qualitatively investigate the patient preferences for the follow-up methods, magnetic resonance imaging with contrast enhanced MR angiography, computed tomography and DSA. Nineteen patients (79%) answered. The questionnaire was constructed according to the principles and methods in nursing research and was developed as closed-ended multiple-choice questions with 4 alternatives, from most favorable to least favorable. The items of the questionnaire were based on interviews with radiographers in charge of each modality and concerned the most common patient experiences. RESULTS: The overall patient experience of magnetic resonance imaging with contrast enhanced MR angiography was more unpleasant than computed tomography. CONCLUSION: The overall patient experience showed no differences between magnetic resonance imaging with contrast enhanced MR angiography and DSA, or between computed tomography and DSA.

Aged↗
PubMed2002

A randomised controlled trial of micronised purified flavonoid fraction vs placebo in patients with chronic venous disease.

OBJECTIVE: to evaluate the efficacy of a micronised purified flavonoid fraction (MPFF) in the treatment of chronic venous disease (CVD). DESIGN: prospective double blind, randomised, control study. PATIENTS AND METHODS: one hundred and one patients with symptomatic CVD were randomly allocated to treatment for 60 days with either MPFF (51 patients) or placebo (50 patients) 500 mg twice daily. There were 28 men and 73 women, aged 22-65 years (mean age 48 years). No difference regarding age, gender, clinical class or duration of symptoms was recorded between the treatment and placebo groups. A global score for evaluation of symptoms was used. Patients were investigated with plethysmography (foot-volumetry) and duplex-ultrasonography before and after the treatment period. For statistical comparison Cochran-Mantel-Haenszel test, two-sided Student t-test and covariance analysis were used and p<0.05 was regarded significant. RESULTS: improvement of the global score of symptoms was reported by 21 patients in the MPFF group and by 16 in the placebo group (N.S.). For the whole groups, no significant differences were recorded before and after treatment regarding foot-volumetric or ultrasonographic parameters. On the other hand, in patients with edema (20 in the MPFF group, 23 in the placebo group) ultrasonographic reflux time was significantly reduced for those in the treatment group (p=0.03). This finding did not correlate to clinical symptoms. CONCLUSION: in this study, MPFF did not change the symptoms of CVD, except night cramps. A secondary finding was reduced reflux times in patients with oedema, although no ultrasonographic or foot-volumetric parameters changed significantly for the whole group. The role of MPFF in treatment of patients with CVD needs to be further analysed in a large population.

Adult↗
PubMed2002

Outcome of treatment of ruptured abdominal aortic aneurysms depending on the type of hospital.

OBJECTIVE: To compare the outcome of patients operated on acutely for ruptured abdominal aortic aneurysms (AAA) or otherwise symptomatic aortic aneurysms in a university hospital and in two county hospitals by the same group of vascular surgeons. DESIGN: Retrospective study. SETTING: 1 university and 2 county hospitals, Sweden. SUBJECTS: 108 patients operated on urgently for AAA, 81 at the university hospital, and 27 at the county hospitals between January 1992 and December 1998. INTERVENTION: Repair of the AAA. MAIN OUTCOME MEASURES: Morbidity and mortality. RESULTS: 21 of the 81 patients having urgent repair of an AAA at the university hospital (26%) had been transferred from the county hospitals. Thirteen patients were not operated on, 7 because of their poor general condition and great age (median 84 years), 3 who refused operation, and 3 in whom the diagnosis was incorrect. During the same time period a further 27 haemodynamically unstable patients were operated on by the same vascular surgeons at the county hospitals. The on-table mortality for patients with ruptured AAA and shock was 5/43 (12%) at the university hospital and 4/27 (15%) at the county hospitals. The corresponding in-hospital rates were 11/43 (26%) and 11/27 (41%). Mortality was significantly higher if the operation was delayed by more than 45 minutes. The incidence of postoperative complications was the same in both hospitals. CONCLUSION: If a patient with a ruptured AAA and shock is admitted to the county hospital and operated on by a specialist vascular surgeon the outcome is fully acceptable. The difference seems to be related to the postoperative period. To what extent the delay caused by the surgeon's journey to the county hospital has any influence on the outcome is not possible to evaluate.

Adult↗
PubMed2001

Regional tissue metabolism during open or endovascular abdominal aortic aneurysm surgery.

OBJECTIVE: to investigate differences in regional tissue metabolism between open and endovascular aneurysm repair utilising a microdialysis technique. MATERIALS: eight patients receiving endovascular stent grafts (STENT) and six patients undergoing open aortic surgery (OPEN) for abdominal aortic aneurysms were studied prospectively but non-randomised. METHOD: microdialysis catheters placed subcutaneously in the pectoral and calf region, respectively. RESULTS: microdialysate glucose levels increased in the OPEN group on the day of surgery. Microdialysate lactate levels increased transiently in the leg in the STENT group. In the OPEN group lactate increased in the leg after aortic cross-clamping. Glycerol decreased in the pectoral region in the STENT group after surgery, but remained elevated in the OPEN group. CONCLUSION: we found indications that the metabolic impact of the two aortic procedures differ. This may be of clinical importance when selecting patients for either open aortic surgery or endovascular stentgrafting.

Adipose Tissue↗
PubMed2001

Percutaneous transluminal angioplasty of crural arteries: diabetes and other factors influencing outcome.

OBJECTIVE: to evaluate the efficacy of percutaneous transluminal angioplasty (PTA) of the crural arteries. PATIENTS AND METHODS: a retrospective review of patients treated with PTA of at least one crural artery during an 8-year period (1990--1997). RESULTS: one hundred and fifty-five legs in 140 consecutive patients (mean age 74 years, range 38--91 years) were treated. In 76% a more proximal lesion was also treated. After 1 year, results were significantly better in non-diabetics (improvement rate of 66% vs 32%p <0.05). The outcome for patients with a combination of diabetes, heart disease and renal disease was significantly worse compared to all other patients with an improvement rate of only 9% after 1 year. Patients alive and not amputated at 1 year were significantly more common (p <0.05) among non-diabetics (90%), compared to diabetics (66%). The 1-year mortality for the whole group was 15%, significantly higher for diabetic patients (p =0.04). CONCLUSION: PTA of crural arteries produces reasonably good results in non-diabetic patients. Diabetic patients were doing worse than non-diabetics after a year, though 1-month results were not significantly different. Patients with diabetes, heart disease and renal disease make a high-risk group that has a significantly worse outcome.

Adult↗
PubMed2001

The inflammatory response and its consequence for the clinical outcome following aortic aneurysm repair.

OBJECTIVE: to review published studies on the outcome of the inflammatory response after abdominal aortic aneurysm (AAA) repair. METHODS: a literature search on PubMed was performed. All studies that determined the inflammatory response (cytokine release) after AAA repair were included. The results of the studies and differences between open and endoluminal repair were compared and evaluated. RESULTS: seventeen studies were identified. In most studies the investigated cytokines were TNF-alpha and IL-6. Determination of IL-1 beta, IL-8, TNFsr1 and TNFsr2 were less often performed. TNF-alpha may reflect, but not strictly predict, the clinical outcome in patients with ruptured AAA. IL-6 levels correlate well with the surgical trauma per se. Variations in recorded cytokine release during endovascular AAA repair may depend on the times of blood sampling. CONCLUSION: both open and endovascular AAA repair provoke a cytokine response. This response is greater during open repair than during endovascular aortic aneurysm exclusion.

Aortic Aneurysm, Abdominal↗
PubMed2001

Spinal cord metabolism during thoracic aortic cross-clamping in pigs with special reference to the effect of allopurinol.

OBJECTIVE: investigate the metabolic response of the spinal cord and the effect of allopurinol following cross clamping of the descending thoracic aorta in a porcine model. DESIGN: experimental animal study. MATERIALS: twelve domestic swine. Six pigs were pre-treated with allopurinol, while six pigs served as controls. METHODS: measurement of extracellular concentrations of glucose, pyruvate, lactate, glycerol and glutamate using microdialysis in the lumbar spinal cord. Measurement of lumbar spinal blood flow using laser Doppler technique. RESULTS: for all animals there was a significant decrease in concentrations of glucose and pyruvate together with a significant increase in the lactate-pyruvate ratio during aortic cross clamping. There was also a significant increase in glycerol concentrations 60 min after cross clamping, and a significant decrease in glutamate concentrations after 50 min. No differences in concentrations of glucose, pyruvate, lactate and glutamate or the glutamate-pyruvate ratio were observed between animals used as controls and those treated with allopurinol. The laser Doppler flux decreased to 40% of pre cross-clamp level, returning to normal values at declamping. CONCLUSION: the changes in energy-related metabolites reflect a considerable ischaemia in the spinal cord tissue but there was no convincing effect of allopurinol on the lumbar spinal cord metabolism during thoracic aortic cross clamping in this model.

Allopurinol↗
PubMed2000

[Varices and venous insufficiency--therapeutic philosophy prior the 2000's].

Varicose veins represent everything from a cosmetic problem to a risk of venous leg ulcers. Predicting the risk of complications has been difficult, not least due to less than satisfactory diagnostic procedures. Recent investigations have pointed out some important new concepts: Superficial venous incompetence may give rise to an ulcer, and such an ulcer may be prevented by varicose vein surgery. Recanalization and stenting may be useful in treating chronic iliac and caval venous occlusions; however, long-term outcome is yet to be established. Venous diameter can be reduced, thus effecting valve competence. To what extent this result is long-lasting is not known. Neither has the method been attempted on deep veins. Clinical diagnosis is never sufficient in cases of suspected chronic venous incompetence. The minimum requirement is the use of a hand-held Doppler. Frequently, a more detailed ultrasonographic analysis is required, and for a global assessment of venous function, plethysmographic techniques are useful. Primary health care may contribute effectively to the care of venous leg ulcers.

Humans↗
PubMed2000

[Vascular surgery after the year of 2000--challenges for the future].

Vascular surgery is in a dynamic phase of rapid development. Particularly endovascular procedures have revolutionized the care of vascular patients. Around 35-40% of all interventions in Sweden are endovascular. In all aspects of vascular surgery (arterial, venous, endovascular, biomaterials) there is a great need for more basic knowledge. The organization of vascular units must be centered around the vascular patient. Specialists need to collaborate in the care of each patient. It is proposed that the care of vascular patients should be organized in Vascular Departments.

Biocompatible Materials↗
PubMed2000

MR evaluation ex vivo and in vivo of a covered stent-graft for abdominal aortic aneurysms: ferromagnetism, heating, artifacts, and velocity mapping.

Magnetic resonance imaging (MRI) safety was evaluated at 1.5 T in a covered nickel titanium stent-graft (Vanguard) used for endovascular treatment of abdominal aortic aneurysms (AAAs). Imaging artifacts were assessed on MRI with contrast-enhanced (CE) three-dimensional (3D) MR angiography (MRA) and spiral computed tomography (CT) in 10 patients as well as ex vivo. Velocity mapping was performed in the suprarenal aorta and femoral arteries in 14 patients before and after stent-graft placement. For comparison it was also performed in six healthy volunteers. No ferromagnetism or heating was detected. Metal artifacts caused minimal image distortion on MRI/MRA. The artifacts disturbed image evaluation on CT at the graft bifurcation and graft limb junction. No significant differences in mean flow were found in patients before and after stent-graft placement. Our study indicates that MRI at 1.5 T may be performed safely in patients with the (Vanguard) stent-graft. MRI/MRA provides diagnostic image information. Velocity mapping is not included in our routine protocol.

Aortic Aneurysm, Abdominal↗
PubMed2000

Microdialysis of the spinal cord during thoracic aortic cross-clamping in a porcine model.

OBJECTIVE: Utilising microdialysis to measure the changes of glucose, lactate, pyruvate and glutamate levels in the spinal cord after cross-clamping of the thoracic aorta in an established porcine model to monitor the degree of ischaemia. DESIGN: Experimental study with a porcine model. SETTING: University Hospital, Trondheim. SUBJECTS: Six pigs. MAIN OUTCOME MEASURE: Lactate, pyruvate and glutamate concentrations in the microdialysis perfusate from the spinal cord. RESULTS: A significant increase of the lactate-pyruvate ratio during the last 30 min of the 1 h clamping period, with a maximum increase of 169% from the basal value the last 10 min before declamping. No evident change in this ratio between the clamping and the reperfusion period. No significant change in glutamate levels during clamping or reperfusion period. CONCLUSION: Microdialysis reflects the ischaemic state of the spinal cord during cross-clamping of the thoracic aorta in pigs, and is well suited to study each phenomena.

Animals↗
PubMed2000

Intraoperative contamination of synthetic vascular grafts. Effect of glove change before graft implantation. A prospective randomised study.

OBJECTIVES: to investigate the incidence of intraoperative graft contamination, bacterial species and the influence of change of surgeon's gloves on contamination. DESIGN: a prospective randomised study. MATERIALS AND METHODS: forty patients had implantation of synthetic vascular grafts. All patients received intraoperative cloxacillin (2.0 g) or clindamycin (0.6 g) intravenously. The procedures were randomised to two groups: Group 1 - surgeons changed the gloves before the first contact with the vascular prosthesis and Group 2 - operation without glove change. The growth of all bacterial species from graft segments and from the gloves was recorded. The susceptibility to antibiotics was tested. RESULTS: the number of contaminated grafts was similar in the two groups. Growth of bacteria was recorded from 92.5% (37/40) of the graft segments and 33% (51/156) of glove imprints. Of the cultured species, 75% and 47%, respectively, were identified as coagulase-negative staphylococci (CNS). Twenty-eight per cent of CNS were resistant to cloxacillin, 15% to clindamycin, and 10% to cloxacillin and clindamycin. In all, 25% of the CNS strains were resistant to the prophylactic antibiotic used. In 50% of cases, the antibiogram of the CNS strain recovered from gloves agreed with that of the strain harvested from the graft. CONCLUSIONS: a high incidence of graft contamination was found which was not reduced by changing gloves. However, changing gloves did seem to reduce the number of bacterial species.

Aged↗
PubMed2000

Response of inflammatory markers to balloon angioplasty in peripheral arterial occlusive disease.

OBJECTIVES: To study the inflammatory response to balloon angioplasty (PTA). DESIGN: Prospective study. MATERIALS: Blood samples were drawn for cytokine analysis from 10 patients undergoing PTA before, after 60 min and 6 h after the balloon inflation. Adhesion molecules were analysed in 14 patients undergoing PTA and in seven patients undergoing angiography only. Arterial samples were taken in eight patients, before PTA, immediately after and 15 min later. Venous samples were taken in six patients and in the group undergoing angiography only. The sampling was before, 60, 90 and 120 min after the procedure. As controls served 15 patients with no signs of peripheral arterial disease. METHODS: Cytokines (IL-6, TNF-alpha) were analysed using ELISA. Adhesion molecule expression on WBC was measured by flow cytometry. RESULTS: A significant increase of IL-6 in the sample taken 6 h after the last balloon inflation was seen in five patients. TNF-alpha was raised only in one patient. The group of patients with peripheral arterial occlusive disease (PAOD) expressed pre-interventionally a higher level of adhesion molecules on WBC compared to the controls. The expression of adhesion molecules (CD11b/CD18) was significantly decreased after PTA. CONCLUSION: Only a very limited cytokine response is caused by PTA reflecting the small surgical trauma. PTA results in a downregulation of detectable CD11b/CD18 expression on WBC in the circulation, which may reflect removal of activated cells through adhesion and extravasation.

Aged↗