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Lars Norgren

Publications and source records attributed to Lars Norgren.

15 recordsLinked to original sources
PubMed2006

Fascia suturing of large access sites after endovascular treatment of aortic aneurysms and dissections.

PURPOSE: To evaluate a technique for closure of a femoral artery access in which the cribriform fascia covering the common femoral artery is sutured. METHODS: A consecutive series of 127 patients (103 men; median age 74 years, range 45- 89) underwent endovascular aortic aneurysm repair between August 2001 and September 2004. Twelve patients underwent a secondary intervention for a total of 139 procedures in the group. Sixty-one (43.9%) of the 139 operations were acute. Among the 257 femoral arteries used for access, a fascia suturing technique was performed in 131 (51.0%). Data were collected for analysis of access site complications, bleeding, thrombosis, pseudoaneurysm, and stenosis. A subgroup of 72 patients had ankle-brachial indexes (ABI) recorded; another subgroup of 50 patients were also investigated by duplex ultrasonography. RESULTS: Complications occurred in 18 (13.7%) of the 131 sutured cases. The majority (n = 16) arose within 24 hours: 8 cases of perioperative bleeding or thrombosis required open surgery and 8 cases were reoperated within 24 hours for bleeding (n = 4), thrombosis (n = 3), and 1 intimal dissection. The acute failure rate was 12.2%. Two patients had late complications: 1 case of neuralgia and 1 pseudoaneurysm that required acute surgery 28 months postoperatively. The ABI did not change significantly from pre- to postoperatively in the 72 patients examined. Five patients with stenoses did not have a reduction in ABI. In the 66 sites examined with ultrasound in 50 patients, 3 minor pseudoaneurysms were detected. CONCLUSION: The fascia suturing technique for closure of a femoral artery access during endovascular repair of aortic diseases is feasible, even in acute situations. Failures can be managed easily. Late complications requiring additional procedures are rare.

Aged↗
PubMed2005

Lipopolysaccharide-induced cytokine and chemokine expression in human carotid lesions.

The release of cytokines and chemokines from activated immune-competent cells plays a crucial role in determining the pathology of the atherogenic progress. We investigated the effect of bacterial lipopolysaccharide (LPS) on cytokine/chemokine expression in carotid lesions and normal renal arteries. The lesions or renal arteries were incubated for 6 h at 37 degrees C in serum-free media treated with or without LPS. After LPS treatment, increased protein levels of IL-1beta, IL-6, IL-8, IL-10, TNF-alpha and MCP-1 were observed in the culture medium from the lesions measured with cytometric bead array. We were able to detect the induction of IL-1beta, IL-6, IL-8, IL-10, TNF-alpha and MCP-1 mRNA in the lesions after stimulation with LPS using real-time PCR. In renal arteries, LPS also induces mRNA expression of all chemokines and cytokines investigated with the exception of IL-6. However, LPS induces significantly higher levels of TNF-alpha, IL-1beta and IL-10 mRNA in lesions compared to renal arteries. The results suggest that infectious agents are capable of enhancing the production of cytokines/chemokines in an already ongoing inflammatory process such as in atherosclerosis, and that low levels of circulating LPS may affect the levels of pro-inflammatory cytokines much more in atherosclerotic vessels than in normal vessels and may contribute to the development of the atherosclerotic lesion.

Carotid Arteries↗
PubMed2005

Endovascular treatment of ruptured abdominal aortic aneurysms: a shift of the paradigm?

PURPOSE: To compare endovascular aneurysm repair (EVAR) of ruptured abdominal aortic aneurysms (rAAA) to the results with open surgery. METHODS: Between May 2001 and January 2004, 50 patients were diagnosed with rAAA. Fifteen (30%) patients (14 men; median age 73 years, range 58-85) underwent EVAR, while 26 (52%) patients (23 men; median age 75 years, range 60-84) had open surgery. Nine (18%) patients (5 men; median age 86 years, range 77-91) were not operated upon. Circulatory shock was defined as systolic blood pressure<80 mmHg. Mortality was defined as death within 30 days after operation; in cases where hospital stay exceeded 30 days, in-hospital mortality was registered. Five risk factors (age>76 years, loss of consciousness, hemoglobin<90 g/L, creatinine>190 micromol/L, and electrocardiographic ischemia) were analyzed. RESULTS: In the EVAR group, 93% (14/15) of the aneurysms were excluded from the bloodstream; there were 2 (13%) conversions: 1 intraoperatively for stent-graft migration and another owing to dissection prior to hospital discharge. Mortality after open surgery was 46% (12/26) versus 13% (2/15) in the EVAR group (p>0.05). Univariate analysis without considering variables other than mortality resulted in OR 5.4 (95% CI 0.9 to 58; p=0.07). Considering risk factors and shock, multivariate analysis resulted in OR 6.5 (95% CI 0.8 to 96; p=0.08). In the EVAR group, 60% (9/15) had complications; in the group with open surgery, the complication rate was 85% (22/26; p=0.13). CONCLUSIONS: It is possible to treat rAAA with EVAR. Hypotensive patients can, at least initially, be operated under local anesthesia to stabilize blood pressure utilizing a percutaneously inserted occlusion balloon. There was a trend in our study for reduced mortality and morbidity with EVAR, but further studies are required to conclude whether EVAR significantly increases survival and reduces complications.

Aged↗
PubMed2004

The chemokine and scavenger receptor CXCL16/SR-PSOX is expressed in human vascular smooth muscle cells and is induced by interferon gamma.

Atherosclerosis is an inflammatory disease that is characterised by the involvement of chemokines that are important for the recruitment of leukocytes and scavenger receptors that mediate foam cell formation. Several cytokines are involved in the regulation of chemokines and scavenger receptors in atherosclerosis. CXCL16 is a chemokine and scavenger receptor and found in macrophages in human atherosclerotic lesions. Using double-labelled immunohistochemistry, we identified that smooth muscle cells in human lesions express CXCL16. We then analysed the effects of IFN-gamma, TNF-alpha, IL-12, IL-15, IL-18, and LPS on CXCL16 expression in cultured aortic smooth muscle cells. IFN-gamma was the most potent CXCL16 inducer and increased mRNA, soluble form, membrane form, and total cellular levels of CXCL16. The IFN-gamma induction of CXCL16 was also associated with increased uptake of oxLDL into these cells. Taken together, smooth muscle cells express CXCL16 in atherosclerotic lesions, which may play a role in the attraction of T cells to atherosclerotic lesions and contribute to the cellular internalisation of modified LDL.

Arteriosclerosis↗
PubMed2004

Intraperitoneal cytokine response after major surgery: higher postoperative intraperitoneal versus systemic cytokine levels suggest the gastrointestinal tract as the major source of the postoperative inflammatory reaction.

BACKGROUND: Cytokine response is an important factor in the development of shock and organ failure. The aim of this study was to investigate intraperitoneal (peritoneal) and venous (systemic) postoperative cytokine release after major surgery. METHODS: Major abdominal surgery was performed in 19 patients. Preoperative systemic measurements and postoperative systemic and peritoneal measurements of C-reactive protein (CRP) and the cytokines tumor necrosis factor-alpha (TNF-alpha), interleukin (IL-6), and IL-10 were performed. RESULTS: Significantly higher TNF-alpha, IL-6, and IL-10 peritoneal values were recorded compared with systemic values, whereas peritoneal CRP was significantly decreased. CRP increased significantly over time, whereas postoperative values of IL-6, IL-10, and peritoneal TNF-alpha decreased. Systemic TNF-alpha was constant over time, but values after emergent abdominal surgery showed a more extensive response. An additional effect of surgery and emergent abdominal disease was seen in increased TNF-alpha and IL-10 levels. CONCLUSIONS: Compared with systemic cytokines, peritoneal cytokines respond extensively after major surgery, indicating that measurement of peritoneal cytokines is a more sensible method to determine postoperative inflammatory reaction. A normal postoperative course is characterized by decreasing levels of peritoneal cytokines.

Adult↗
PubMed2004

Can low molecular weight heparin replace unfractionated heparin during peripheral arterial reconstruction? An open label prospective randomized controlled trial.

OBJECTIVE: This study was undertaken to evaluate the effect of low molecular weight heparin (LMWH) compared with unfractionated heparin (UFH) on the rate of occlusion and bleeding during peripheral vascular surgery. METHODS: The study was an open label, prospective, randomized trial, carried out by 20 Swedish surgical and vascular surgical departments that report to the Swedish Vascular Registry (SWEDVASC). Study subjects included patients undergoing peripheral vascular procedures, except carotid surgery. Of the 849 patients included, 817 were followed up to 30 days. LMWH (40 mg of enoxaparin) or UFH (5000 IU heparin) was given intravenously immediately before clamping. The same formulation in diluted form was used for vascular rinsing. Main outcome measures included patent reconstruction at day 1, perioperative blood loss, and the percentage of patients requiring protamin. Further, 30-day data for mortality, repeat operation, and recurrent occlusion are reported. RESULTS: The mortality rate at 30 days was 2.7%, with no difference between groups. The patency rate at 1 day was 91.2% to 98.4%, depending on diagnosis and type of reconstruction. No difference was recorded between study groups (0.6 < P < 1.0). At 30 days the patency rate was 83.1% to 100% (0.2 < P <.9). Median blood loss was 350 mL (interquartile range [IQR], 200-800 mL) in the LMWH group and 425 mL (IQR, 200-900 mL) in the UFH group (P =.02). Protamin was given to significantly fewer patients in the LMWH group (P =.001). LMWH was comparable to UFH during peripheral vascular reconstruction in terms of 1-day and 30-day graft patency, operative blood loss, and hemorrhagic complications. Protamine was required less often after LMWH. In this randomized trial LMWH was as effective as UFH in preventing thrombosis without excess bleeding or hemorrhagic complications.

Aged↗
PubMed2003

Venous function after restoring valve competence of the great saphenous vein.

PURPOSE: To measure changes in venous function after elimination of great saphenous vein reflux using endovenously-applied heat with a specially designed catheter. METHODS: In a prospective clinical study, 13 patients (8 women; mean age 39 years, range 25-59) with symptomatic chronic venous insufficiency were treated for reflux at the saphenofemoral junction. A radiofrequency catheter (Restore) with expandable electrodes that shrinks the vein by controlled constriction of subendothelial collagen was used to restore valve competence. Extirpation of local varicosities was performed simultaneously. Main outcome was change in venous function as measured by plethysmography (foot volumetry) and change in diameter and reflux time at the saphenofemoral junction after 6 and 12 months. RESULTS: Reflux in the greater saphenous vein was eliminated or reduced to below 0.5 seconds in all patients. The venous function was significantly improved after 6 months' follow-up, with decreased refilling rate/expelled volume related to foot volume (p=0.019). The patients were clinically improved, although only 7 (54%) were entirely free from reflux. Three (21%) patients had thrombus in the vein the day after the treatment, 2 at the treatment site and 1 at the entry site of the introducer. After 1 year, the patients are still satisfied with the results, although venous function is no longer significantly improved compared to baseline. CONCLUSIONS: It is possible to safely restore valvular competence by means of internally shrinking the vein diameter. The venous function is improved, although the vein has a tendency to increase in width with time; limited reflux reappears, with deterioration of venous function.

Adult↗
PubMed2003

Flavonoid treatment in patients with healed venous ulcer: flow cytometry analysis suggests increased CD11b expression on neutrophil granulocytes in the circulation.

The objective was to determine the activation of white blood cells (WBCs) and endothelial cells in patients with healed venous ulcer and the influence of the standing position and of treatment with flavonoids. Ten patients with a healed venous ulcer were treated with flavonoid substance (90% diosmin), 1000 mg three times daily for 30 days. Blood samples were taken from arm and dorsal foot veins before and after standing for 30 minutes. Blood sampling was performed before treatment, after three days, one month and three months. The activation of WBCs was determined by measuring adhesion molecule CD11b and CD18 expression on the surface of granulocytes and monocytes. In addition, interleukin 6 (IL-6), IL-8, soluble E-selectin (sE-selectin), sL-selectin and sICAM-1 levels in serum were quantified. The results showed that standing did not influence any of the measured parameters significantly. Expression of CD11b adhesion molecules on granulocytes was significantly up-regulated (p = 0.044) after treatment with flavonoids for one month, but this increase was not significant (p = 0.056) two months after the treatment period compared with the baseline level. The expression of CD18 remained unchanged. Baseline expression of CD11b or CD18 on monocytes did not change significantly during the study period. Neither was any significant change observed in the levels of IL-6, IL-8 or the soluble adhesion molecules. It was concluded that flavonoid treatment for 30 days increased the expression of CD11b adhesion molecules on circulating granulocytes. No general effect on the inflammatory process could be observed as assessed by levels of cytokines and soluble adhesion molecules. Possible explanations for these findings could be that a decreased number of primed granulocytes leave the circulation due to a changed WBC/endothelial cell interaction or that flavonoids have a direct effect on granulocytes. Further studies are needed to clarify the mode of action of flavonoids in chronic venous disease.

Adult↗
PubMed2002

Significance of endoleaks after endovascular repair of abdominal aortic aneurysms: The EUROSTAR experience.

OBJECTIVE: The purpose of this study was to assess the incidence, risk factors, and consequences of endoleaks after endovascular repair of abdominal aortic aneurysm. METHODS: Data on 2463 patients were collected from 87 European centers and recorded in a central database. Preoperative data were compared for patients with collateral retrograde perfusion (type II) endoleak (group A), patients with device-related (type I and III) endoleaks (group B), and patients in whom no endoleak was detected (group C). Only endoleaks observed after the first postoperative month of follow-up were taken into consideration. Regression analysis was performed to investigate statistical relationships between the occurrence and type of endoleak and preoperative patient and morphologic characteristics, operative details, type of device, and experience of the operating team. In addition, postoperative changes in aneurysmal morphology, the need for secondary interventions, conversions to open repair, aneurysmal rupture, and mortality during follow-up were compared between these study groups. RESULTS: Patients in group A had a higher prevalence of a patent inferior mesenteric artery compared with patients without endoleak. Patients in group B were treated more frequently than patients in group C by an operating team with experience of less than 30 procedures. The mean follow-up period was 15.4 months. Secondary interventions were needed in 13% of the patients. Rupture of the aneurysm during follow-up occurred in 0.52% (1/191) in group A, 3.37% (10/297) in group B, and 0.25% (5/1975) in group C. Life table analysis comparing the three study groups demonstrated a significantly higher rate of rupture in group B than in group C (P =.002). The incidence of conversion to open repair during follow-up was higher in group B than in the other two study groups (P <.01). Death was related to the aneurysm or to endovascular repair of the aneurysm in 7% of patients. Secondary outcome success, defined as absence of rupture and conversion, was significantly higher in group A and C compared with that in group B (P =.006 and P =.0001, respectively). CONCLUSIONS: The presence of device-related endoleaks correlated with a higher risk of aneurysmal rupture and conversion compared with patients without type I or III endoleaks. Type II endoleak was not associated more often with these events. Consequently, intervention in type II endoleak should only be performed in case of increase of aneurysm size.

Adult↗
PubMed2002

Intraoperative angioscopy may improve the outcome of in situ saphenous vein bypass grafting: a prospective study.

OBJECTIVE: To find out whether intraoperative angioscopic assistance has any effect on graft outcome in patients with critical leg ischemia. MATERIAL AND METHODS: One hundred one patients requiring a below-knee bypass were assigned to undergo in situ saphenous vein bypass with or without intraoperative angioscopic assistance; otherwise treated similarly including preoperative duplex vein mapping, intraoperative graft flow measurements, and angiography. Data on operative details, morbidity, hospital stay, and graft patency were collected prospectively and compared. All patients were followed up for 12 months. RESULTS: The group that underwent angioscopy (A) and the control group (B) were similar in all respects, except for the number of patients enrolled in the groups (32 and 69, respectively). Angioscopy revealed incompletely destructed valves in 34 patients (range, 0 to 5; mean 1), undiagnosed vein branches in 111 patients (mean 4.3), and partly occluding thrombus in 5 patients. The number of postoperative arteriovenous fistulas with signs of failing graft and a need for angiographic or surgical reintervention were significantly higher in group B (P <.0001). The 1-year primary patency rate was significantly better in group A (P <.01), but the primary assisted and secondary patency rates did not differ between the groups. CONCLUSIONS: Angioscopic assistance has an impact on primary graft patency, minimizes the risk for graft failure and thus reduces the need for reintervention by allowing identification of persistent saphenous vein branches, incomplete valve destruction, and partly occluding graft thrombus without adding extra operative time.

Aged↗
PubMed2002

Salvage of an acutely ruptured thoracic aortic aneurysm during CPR.

PURPOSE: To report the successful endovascular treatment of a ruptured thoracic aortic aneurysm during cardiopulmonary resuscitation. CASE REPORT: A 72-year-old woman with a type B aortic dissection treated conservatively for 8 years was referred for rupture of a 16-cm aneurysm of the descending thoracic aorta. During transfer to the operating room, the patient suffered cardiac arrest; cardiopulmonary resuscitation (CPR) was initiated. A few minutes later during CPR, the surgical procedure began with a cutdown of the right femoral artery and insertion of a guidewire and an aortic occlusion balloon, which was inflated at the origin of the left subclavian artery (LSA). Blood pressure was immediately measurable. By only partially deflating the occluding balloon, a thoracic stent-graft was advanced above it and deployed at the origin of the LSA while rapidly deflating and retracting the occluding balloon. Three stent-grafts were required to cover 27 cm of the descending aorta. The patient was partly ventilator dependent for 3 months due to a massive pleural hematoma that was not evacuated. At the 10-month follow-up, the patient is fully recovered without any sign of respiratory dysfunction or any other sequela. CT scans reveal that the massive hematoma is almost completely resolved. CONCLUSIONS: This case illustrates that optimal collaboration between anesthesiologists, interventional radiologists, and vascular surgeons with appropriate resources can significantly expand the possibilities of emergent treatment in the face of aortic rupture.

Acute Disease↗
PubMedDate not supplied

[Endovascular treatment possible in ruptured abdominal aortic aneurysm].

Since 1996 we have performed endovascular treatment (EVAR, endovascular aortic aneurysm repair) for elective abdominal aortic aneurysms (AAA) and since 2001 also for ruptured AAA (rAAA). All patients who were treated for rAAA during the period May 2001-January 2004 were retrospectively studied. Mortality was defined as 30-day mortality or hospital mortality when the hospital stay exceeded 30 days. 50 patients had rAAA, nine of them were not operated upon. 26 patients had open surgery, 15 had EVAR. Five risk predictors according to Hardman (age >76 years, loss of consciousness, Hb 90 g/l, creatinine level >0.19 mmol/l and electrocardiographic ischemia) as well as shock (BP <80 mm Hg) were registered. The mortality among the patients after open surgery was 46% and after EVAR 13%. By considering risk factors and shock a multivariate analysis resulted in OR = 6.5 (95% CI: 0.8-96; p = 0.079), supporting that any selection of the material had not influenced the result. We conclude that it is possible to treat rAAA with EVAR. Hypotensive patients can, at least initially, be operated under local anaesthesia with stabilization of blood pressure utilizing a percutaneously inserted occlusion balloon. Further studies are required to conclude whether EVAR significantly increases survival and reduces complications.

Aged↗