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Featured researches published by Gudmundur Danielsson.


Vascular and Endovascular Surgery | 2002

The Influence of Obesity on Chronic Venous Disease

Gudmundur Danielsson; Bo Eklof; Andrew Grandinetti; Robert L. Kistner

The authors investigate the impact of overweight in patients with chronic venous disease and determine if the eventual effect can be explained by increased venous reflux alone. Patients with chronic venous disease who underwent duplex-ultrasound scanning at the Vascular Center, Straub Clinic and Hospital during 1999 were classified according to the clinical, etiologic, anatomic, and pathophysiologic (CEAP) system and body mass index (kg/M2) was calculated. Reflux duration was measured in seconds and peak reverse flow velocity in cm/second. Multisegment reflux score (total score) was calculated for both reflux duration and peak reverse flow velocity. The reflux pattern and body mass index were correlated to the clinical presentation. Four hundred and one lower extremities (204 right, 197 left) in 272 patients (173 female) with a mean age of 60 years (range 14-90) were investigated. The mean body mass index was 28.9 (±7.76). One hundred sixty-seven patients (61%) were overweight (body mass index 25 kg/M2 or more). There was a significant association between body mass index and the clinical severity (p < 0.001). This association persisted after adjustments for total peak reverse flow velocity and total reflux score were made (p <0.001). Overweight patients were more likely to have skin changes and ulceration (p < 0.001) than patients with a body mass index less than 25 kg/m2, despite similar values for total reflux time (p = 0.92) and total peak reverse flow velocity (p = 0.98). There was an ethnic difference, with Pacific Islanders being significantly heavier and younger compared to patients of white, Asian and Filipino ancestries. The variations in the frequency of skin changes were consistent with ethnic differences in body mass index. The correlation of body mass index with clinical severity independent of reflux measurements indicates that the effect of overweight may involve a mechanism separate from local effects on venous flow. Overweight appears to be a separate risk factor for increased severity of skin changes in patients with chronic venous disease.


Journal of Vascular Surgery | 2003

Deep axial reflux, an important contributor to skin changes or ulcer in chronic venous disease ☆

Gudmundur Danielsson; Bo Eklof; Andrew Grandinetti; Fedor Lurie; Robert L. Kistner

OBJECTIVE We undertook this cross-sectional study to investigate the distribution of venous reflux and effect of axial reflux in superficial and deep veins and to determine the clinical value of quantifying peak reverse flow velocity and reflux time in limbs with chronic venous disease. PATIENTS AND METHODS Four hundred one legs (127 with skin changes, 274 without skin changes) in 272 patients were examined with duplex ultrasound scanning, and peak reverse flow velocity and reflux time were measured. Both parameters were graded on a scale of 0 to 4. The sum of reverse flow scores was calculated from seven venous segments, three in superficial veins (great saphenous vein at saphenofemoral junction, great saphenous vein below knee, small saphenous vein) and four in deep veins (common femoral vein, femoral vein, deep femoral vein, popliteal vein). Axial reflux was defined as reflux in the great saphenous vein above and below the knee or in the femoral vein to the popliteal vein below the knee. Reflux parameters and presence or absence of axial reflux in superficial or deep veins were correlated with prevalence of skin changes or ulcer (CEAP class 4-6). RESULTS The most common anatomic presentation was incompetence in all three systems (superficial, deep, perforator; 46%) or in superficial or perforator veins (28%). Isolated reflux in one system only was rare (15%; superficial, 28 legs; deep, 14 legs; perforator, 18 legs). Deep venous incompetence was present in 244 legs (61%). If common femoral vein reflux was excluded, prevalence of deep venous incompetence was 52%. The cause, according to findings at duplex ultrasound scanning, was primary in 302 legs (75%) and secondary in 99 legs (25%). Presence of axial deep venous reflux increased significantly with prevalence of skin changes or ulcer (C4-C6; odds ratio [OR], 2.7; 95% confidence interval [CI], 1.56-4.67). Of 110 extremities with incompetent popliteal vein, 81 legs had even femoral vein reflux, with significantly more skin changes or ulcer, compared with 29 legs with popliteal reflux alone (P =.025). Legs with skin changes or ulcer had significantly higher total peak reverse flow velocity (P =.006), but the difference for total reflux time did not reach significance (P =.084) compared with legs without skin changes. In contrast, presence of axial reflux in superficial veins did not increase prevalence of skin changes (OR, 0.73; 95% CI, 0.44-1.2). Incompetent perforator veins were observed as often in patients with no skin changes (C0-C3, 215 of 274, 78%) as in patients with skin changes (C4-C6, 106 of 127, 83%; P =.25). CONCLUSION Continuous axial deep venous reflux is a major contributor to increased prevalence of skin changes or ulcer in patients with chronic venous disease compared with segmental deep venous reflux above or below the knee only. The total peak reverse flow velocity score is significantly higher in patients with skin changes or ulcer. It is questionable whether peak reverse flow velocity and reflux time can be used to quantify venous reflux; however, if they are used, peak reverse flow velocity seems to reflect venous malfunction more appropriately.


Circulation | 2016

Variations in Abdominal Aortic Aneurysm Care: A Report from the International Consortium of Vascular Registries

Adam W. Beck; Art Sedrakyan; Jialin Mao; Maarit Venermo; Rumi Faizer; Sebastian Debus; Christian-Alexander Behrendt; Salvatore T. Scali; Martin Altreuther; Marc L. Schermerhorn; B. Beiles; Zoltán Szeberin; Nikolaj Eldrup; Gudmundur Danielsson; Ian A. Thomson; Pius Wigger; Martin Björck; Jack L. Cronenwett; Kevin Mani

Background: This project by the ICVR (International Consortium of Vascular Registries), a collaboration of 11 vascular surgical quality registries, was designed to evaluate international variation in the contemporary management of abdominal aortic aneurysm (AAA) with relation to recommended treatment guidelines from the Society for Vascular Surgery and the European Society for Vascular Surgery. Methods: Registry data for open and endovascular AAA repair (EVAR) during 2010 to 2013 were collected from 11 countries. Variations in patient selection and treatment were compared across countries and across centers within countries. Results: Among 51 153 patients, 86% were treated for intact AAA (iAAA) and 14% for ruptured AAA. Women constituted 18% of the entire cohort (range, 12% in Switzerland–21% in the United States; P<0.01). Intact AAAs were repaired at diameters smaller than recommended by guidelines in 31% of men (<5.5 cm; range, 6% in Iceland–41% in Germany; P<0.01) and 12% of women with iAAA (<5 cm; range, 0% in Iceland–16% in the United States; P<0.01). Overall, use of EVAR for iAAA varied from 28% in Hungary to 79% in the United States (P<0.01) and for ruptured AAA from 5% in Denmark to 52% in the United States (P<0.01). In addition to the between-country variations, significant variations were present between centers in each country in terms of EVAR use and rate of small AAA repair. Countries that more frequently treated small AAAs tended to use EVAR more frequently (trend: correlation coefficient, 0.51; P=0.14). Octogenarians made up 23% of all patients, ranging from 12% in Hungary to 29% in Australia (P<0.01). In countries with a fee-for-service reimbursement system (Australia, Germany, Switzerland, and the United States), the proportions of small AAA (33%) and octogenarians undergoing iAAA repair (25%) were higher compared with countries with a population-based reimbursement model (small AAA repair, 16%; octogenarians, 18%; P<0.01). In general, center-level variation within countries in the management of AAA was as important as variation between countries. Conclusions: Despite homogeneous guidelines from professional societies, significant variation exists in the management of AAA, most notably for iAAA diameter at repair, use of EVAR, and the treatment of elderly patients. ICVR provides an opportunity to study treatment variation across countries and to encourage optimal practice by sharing these results.


Vascular and Endovascular Surgery | 2004

Reflux from Thigh to Calf, the Major Pathology in Chronic Venous Ulcer Disease: Surgery Indicated in the Majority of Patients

Gudmundur Danielsson; Berndt Arfvidsson; Bo Eklof; Robert L. Kistner; Elna M. Masuda; Dean T. Sato

The aim of this study was to define the underlying anatomical and pathophysiological conditions in limbs with venous ulcers in order to get information for the most appropriate treatment selection. Ninety-eight limbs (83 patients, 59 men), with active chronic venous ulcers, were analyzed retrospectively and classified according to the CEAP (clinical, etiological, anatomical, and pathophysiological) classification. Duplex-ultrasound was performed in all patients, while air-plethysmography and venography were performed selectively on potential candidates for deep venous reconstruction. Sixty-six ulcers were primary in origin and 32 were secondary. Reflux was present in all limbs except 1. Isolated reflux in 1 system (superficial = 3, deep = 4, perforator = 3) was seen in 10 legs (10%), while incompetence in all 3 systems was seen in 51 legs (52%). Superficial reflux with or without involvement of other systems was seen in 84 legs (86%), 72 legs (73%) had deep reflux with or without involvement of other systems, and incompetent perforator veins were identified in 79 limbs (81%). Axial reflux (continuous reverse flow from the groin region to below knee) was found in 77 limbs (79%). The femoral vein was the single most common deep venous segment in which either reflux or obstruction was found. Axial distribution of disease was found in the majority of cases and no patient had isolated deep venous incompetence below knee. Primary disease was the predominant etiologic cause and reflux was the main pathophysiological finding. Practically all patients were found to have 1 or more sites of reflux or obstruction that could benefit from operative treatment.


European Journal of Surgery | 2002

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

Zbigniew Zdanowski; Gudmundur Danielsson; Torbjörn Jonung; J Kaij; Else Ribbe; Ch Sahlin; Patrik Schatz; Johan Thörne; Lars Norgren

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 surgeons journey to the county hospital has any influence on the outcome is not possible to evaluate.


Phlebology | 2002

Effects of Compression Hosiery in Female Workers with a Standing Profession

C Jungbeck; Klas Peterson; Gudmundur Danielsson; Lars Norgren

Objective: To evaluate the effect of compression hosiery during standing work. Design: An open study, comparing symptoms and plethysmographic findings before and after treatment. Setting: University hospital, vascular surgery. Subjects: Forty-eight female volunteers with a standing profession. Methods: Visual analogue scale to evaluate symptoms and foot volumetry to study venous function before and after 4 weeks use of compression hosiery (20–30 mmHg). Result: All scores for symptoms were significantly reduced after treatment. Only 21% of the study subjects had minor abnormalities on foot volumetry. The expelled volume was significantly higher after work at 4 weeks than at the first measurement at inclusion, while the refilling rate was significantly lower after work at 4 weeks than at the corresponding measurement at inclusion. Conclusion: Symptomatic improvement was recorded after compression treatment. Limited effects were seen with the objective measurement, although the most important factor, the refilling rate, diminished significantly during the treatment period. Compression treatment reduces lower limb symptoms following standing work.


European Journal of Vascular and Endovascular Surgery | 2017

Editor's Choice - Carotid Stenosis Treatment: Variation in International Practice Patterns.

Maarit Venermo; Grace J. Wang; Art Sedrakyan; Jialin Mao; Nikolaj Eldrup; R. DeMartino; Kevin Mani; Martin Altreuther; B. Beiles; Gábor Menyhei; Gudmundur Danielsson; Ian A. Thomson; G. Heller; Carlo Setacci; Martin Björck; Jack L. Cronenwett

OBJECTIVES The aim was to determine current practice for the treatment of carotid stenosis among 12 countries participating in the International Consortium of Vascular Registries (ICVR). METHODS Data from the United States Vascular Quality Initiative (VQI) and the Vascunet registry collaboration (including 10 registries in Europe and Australasia) were used. Variation in treatment modality of asymptomatic versus symptomatic patients was analysed between countries and among centres within each country. RESULTS Among 58,607 procedures, octogenarians represented 18% of all patients, ranging from 8% (Hungary) to 22% (New Zealand and Australia). Women represented 36%, ranging from 29% (Switzerland) to 40% (USA). The proportion of carotid artery stenting (CAS) among asymptomatic patients ranged from 0% (Finland) to 26% (Sweden) and among symptomatic patients from 0% (Denmark) to 19% (USA). Variation among centres within countries for CAS was highest in the United States and Australia (from 0% to 80%). The overall proportion of asymptomatic patients was 48%, but varied from 0% (Denmark) to 73% (Italy). There was also substantial centre level variation within each country in the proportion of asymptomatic patients, most pronounced in Australia (0-72%), Hungary (5-55%), and the United States (0-100%). Countries with fee for service reimbursement had higher rates of treatment in asymptomatic patients than countries with population based reimbursement (OR 5.8, 95% CI 4.4-7.7). CONCLUSIONS Despite evidence about treatment options for carotid artery disease, the proportion of asymptomatic patients, treatment modality, and the proportion of women and octogenarians vary considerably among and within countries. There was a significant association of treating more asymptomatic patients in countries with fee for service reimbursement. The findings reflect the inconsistency of the existing guidelines and a need for cooperation among guideline committees all over the world.


European Journal of Vascular and Endovascular Surgery | 2015

Quality Improvement in Vascular Surgery: The Role of Comparative Audit and Vascunet

D.C. Mitchell; Maarit Venermo; Kevin Mani; Martin Björck; Thomas Troëng; Sebastian Debus; Zoltán Szeberin; A K Hansen; B. Beiles; Carlo Setacci; David Bergqvist; Gábor Menyhei; G. Heller; Gudmundur Danielsson; Ian M. Loftus; Ian A. Thomson; K Vogt; L P Jensen; Martin Altreuther; Nikolaj Eldrup; Pius Wigger; R Moreno-Carriles; T. Lees

Most nations with developed healthcare systems have a strong interest in audit, both for financial and clinical quality control. Whereas financial control has been a key political requirement for managing healthcare, the use of clinical outcome data has, until recently, taken more of a back seat. Clinical audit has a long history of describing outcomes and challenging established attitudes or practice. Responses to published audits vary. Some clinicians voice criticism of bias as a result of selective reporting, either from a few units, or because of incomplete datasets. Attitudes have gradually changed with improved understanding of the role of audit as a tool to examine and refine standards of practice. This has been accompanied by a growth in clinical audit across all branches of medicine. The turn of the century marked a shift towards more widespread clinical audit, with development of political interest in using quality to justify or contain costs. The advent of organisations such as the National Institute for Clinical Excellence (NICE) in the UK saw a growth in the use of research and audit to set standards both for outcomes and processes of care. A good example of this in vascular surgery is the NICE clinical guideline 68, which sets out clear standards for assessment, referral, and treatment of patients with TIA and minor stroke. These standards are incorporated into national audits in Europe and reporting now encompasses both outcomes and performance indicators such as timeliness of surgery and cranial nerve injury. Such reporting has driven improvement in quality of services by focussing clinicians on key components of highquality pathways of care. Vascunet was formed in 1997 as a collaboration of national registries in Europe, New Zealand, and the state of Victoria in Australia, with its first report produced in 2007. Since then, the Vascunet group have published comparative data on carotid surgery, abdominal aortic aneurysm, lower limb bypass, and popliteal artery aneurysm. One of the key features of these publications has been to describe the variation in clinical practice across neighbouring countries, notable examples being rates of surgery for asymptomatic stenosis and rates of lower limb bypass for intermittent claudication. Variation in outcomes is also reported at a national level. The value of such reporting was demonstrated by the 2008 Vascunet report. This demonstrated outlying mortality


Vascular Medicine | 2003

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

Gudmundur Danielsson; Lars Norgren; Lennart Truedsson; Annica Andreasson; Peter Danielsson; Anna Nilsson; P. Swartbol

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.


European Journal of Vascular and Endovascular Surgery | 2018

International Consortium of Vascular Registries Consensus Recommendations for Peripheral Revascularisation Registry Data Collection

Christian-Alexander Behrendt; Daniel J. Bertges; Nikolaj Eldrup; Adam W. Beck; Kevin Mani; Maarit Venermo; Zoltán Szeberin; Gábor Menyhei; Ian A. Thomson; Georg Heller; Pius Wigger; Gudmundur Danielsson; Giuseppe Galzerano; Cristina Lopez; Martin Altreuther; Birgitta Sigvant; Henrik Christian Rieß; Art Sedrakyan; B. Beiles; Martin Björck; Jonathan R. Boyle; E. Sebastian Debus; Jack L. Cronenwett

OBJECTIVE/BACKGROUND To achieve consensus on the minimum core data set for evaluation of peripheral arterial revascularisation outcomes and enable collaboration among international registries. METHODS A modified Delphi approach was used to achieve consensus among international vascular surgeons and registry members of the International Consortium of Vascular Registries (ICVR). Variables, including definitions, from registries covering open and endovascular surgery, representing 14 countries in ICVR, were collected and analysed to define a minimum core data set and to develop an optimum data set for registries. Up to three different levels of variable specification were suggested to allow inclusion of registries with simpler versus more complex data capture, while still allowing for data aggregation based on harmonised core definitions. RESULTS Among 31 invited experts, 25 completed five Delphi rounds via internet exchange and face to face discussions. In total, 187 different items from the various registry data forms were identified for potential inclusion in the recommended data set. Ultimately, 79 items were recommended for inclusion in minimum core data sets, including 65 items in the level 1 data set, and an additional 14 items in the more specific level 2 and 3 recommended data sets. Data elements were broadly divided into (i) patient characteristics; (ii) comorbidities; (iii) current medications; (iv) lesion treated; (v) procedure; (vi) bypass; (vii) endarterectomy (viii) catheter based intervention; (ix) complications; and (x) follow up. CONCLUSION A modified Delphi study allowed 25 international vascular registry experts to achieve a consensus recommendation for a minimum core data set and an optimum data set for peripheral arterial revascularisation registries. Continued global harmonisation of registry infrastructure and definition of items will overcome limitations related to single country investigations and enhance the development of real world evidence.

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Martin Björck

Uppsala University Hospital

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