Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where George S. Sfyroeras is active.

Publication


Featured researches published by George S. Sfyroeras.


Journal of Vascular Surgery | 2013

The impact of endograft type on inflammatory response after endovascular treatment of abdominal aortic aneurysm

Konstantinos G. Moulakakis; Maria Alepaki; George S. Sfyroeras; Constantine N. Antonopoulos; Triantafillos G. Giannakopoulos; John Kakisis; Petros Karakitsos; Christos D. Liapis

OBJECTIVEnTo evaluate the impact of endograft type on the inflammatory response after elective endovascular repair of abdominal aortic aneurysms.nnnMETHODSnFrom January 2011 to November 2011, we included 100 consecutive patients who underwent elective abdominal aortic aneurysm endovascular repair. Thirteen patients were excluded from the analysis: four with cancer, three with autoimmune disease, two because of recent infection, two who were receiving long-term anti-inflammatory medication, and two because of recent surgery. Temperature, white blood cell count, platelet count, and serum concentrations of cytokines (interleukin [IL]-6, IL-8, and IL-10) were measured preoperatively, 24 hours postoperatively, and 48 hours postoperatively. The study sample was divided into four groups with respect to the type of endograft used: group A, n = 28 (Anaconda; Sulzer Vascutek, Bad Soden, Germany); group B, n = 26 (Zenith; Cook Inc, Bloomington, Ind); group C, n = 23 (Excluder; W. L. Gore and Assoc, Flagstaff, Ariz); and group D, n = 10 (Endurant; Medtronic, Minneapolis, Minn). Endograft configurations included bifurcated grafts only.nnnRESULTSnEpidemiologic characteristics, atherosclerotic risk factors, type of anesthesia, mean blood loss during surgery, and baseline serum levels of cytokines did not differ among the four groups. Mean elevated temperature was more pronounced postoperatively in group A. Serum levels of IL-6 and IL-10 were significantly higher 24 hours and 48 hours postoperatively compared with preoperative levels in all groups. Patients in group C showed the smallest increase in levels of serum IL-6 and IL-10 at 24 hours and 48 hours postoperatively. Mean difference in cytokine levels after aneurysm exclusion was greater for group A vs group C (P < .01) compared with group A vs B (P < .05). No differences in the mortality and morbidity rates were observed among the four groups.nnnCONCLUSIONSnEndograft type appears to influence the inflammatory response after endovascular aortic repair. The postimplantation syndrome was apparent during the first 24 hours and decreased afterward. Anaconda and Zenith endografts induced a more intense inflammatory response. A milder inflammatory activation was observed in patients with an Excluder endograft. The postimplantation syndrome was not associated with perioperative adverse clinical events showing a benign course. The possible long-term sequelae of postimplantation syndrome require further investigation.


Thrombosis Research | 2014

The role of soluble P selectin in the diagnosis of venous thromboembolism

Constantine N. Antonopoulos; George S. Sfyroeras; John Kakisis; Konstantinos G. Moulakakis; Christos D. Liapis

INTRODUCTIONnSoluble P selectin (sPsel), a member of the selectin family of cell adhesion receptors, has been proposed as a key molecule in hemostasis and thrombosis mediating platelet rolling, generating procoagulant microparticles and enhancing fibrin deposition. The aim of this study was to examine the role of sPsel in the diagnosis of venous thromboembolism (VTE).nnnMATERIALS AND METHODSnWe performed a systematic review and we used meta-analysis to synthesize data from published studies reporting sPsel levels in patients with i) VTE (deep venous thrombosis; DVT or DVT and pulmonary embolism; PE) and ii) DVT only. Pooled Odds Ratios (ORs) with 95% Confidence Intervals (CIs) were appropriately calculated among patients and controls. Diagnostic performance of sPsel was tested with pooled sensitivity, specificity, Diagnostic Odds Ratio (DOR) and summary receiver operator characteristic (SROC) curve.nnnRESULTSnEleven studies, comprising of 586 VTE patients and 1,843 controls were deemed eligible. The sPsel was significantly increased after VTE (OR=2.89, 95%CI=2.31-3.61, p<0.001), or DVT only (OR=2.64, 95%CI=1.95-3.56, p<0.001). Subgroup analysis evidenced that sPsel was also increased after VTE when evaluating only studies with patients that had no prior medical history (OR=2.88, 95%CI=1.98-4.19, p<0.001). Exclusion of studies including patients with solid organ tumor, HIV or lupus anticoagulants positive patients did not alter findings. Pooled sensitivity and specificity of sPsel was 0.57 (95%CI=0.30-082, p<0.001) and 0.73 (95%CI=0.51-0.90, p<0.001), respectively and DOR was 4.31 (95%CI=2.22-8.37, p<0.01). SROC curve yielded in significant accuracy of sPsel performance (AUC=0.74, p=0.05).nnnCONCLUSIONSnThe sPsel was significantly elevated in patients with DVT, both uncomplicated and complicated with PE and presented with high levels of diagnostic performance. sPsel is a plasma biomarker that may help in the diagnosis of VTE.


Annals of Vascular Surgery | 2015

Bibliometric analysis of factors predicting increased citations in the vascular and endovascular literature.

George A. Antoniou; Stavros A. Antoniou; Efstratios Georgakarakos; George S. Sfyroeras; George S. Georgiadis

BACKGROUNDnDissemination of research findings in the scientific community is reflected by the citation count. Our objective was to investigate the relative citation impact of vascular research studies and identify potential predictors of increased citation rates.nnnMETHODSnArticles published in leading journals of vascular and general surgery (Journal of Vascular Surgery, European Journal of Vascular and Endovascular Surgery, Journal of Endovascular Therapy, Annals of Vascular Surgery and Annals of Surgery, British Journal of Surgery, Journal of the American College of Surgeons, and JAMA Surgery) during a 4-month period were identified through electronic databases. Variables potentially associated with increased citation rates, including subject, design, title characteristics, article length, bibliographic references, authorship, geographic distribution, interdisciplinary collaboration, article access, and funding, were assessed in univariate and multiple linear regression models through December 2012.nnnRESULTSnA total of 226 articles with a total number of 4,605 citations were identified. Univariate analysis revealed that endovascular-related studies, study design, studies reporting design in the title, long articles, and studies with high number of references were associated with higher citation rates. On multivariate analysis, 3 variables were found to independently predict the number of citations: study subject (endovascular-related studies; regression coefficient [95% confidence interval], 0.474 [0.240-0.708]; P < 0.001); study design (randomized controlled trial; regression coefficient [95% confidence interval], 0.575 [0.145-1.005]; P = 0.009); and article length (number of pages; regression coefficient [95% confidence interval], 0.069 [0.016-0.123]; P = 0.011).nnnCONCLUSIONSnAuthors involved in vascular research may enhance the impact of their work by embarking on research strategies of high methodologic quality and pursuing work related with new technologies and evolving endovascular therapies.


Annals of Vascular Surgery | 2015

The Impact of Carotid Artery Stenting on Cognitive Function in Patients with Extracranial Carotid Artery Stenosis

Constantine N. Antonopoulos; John Kakisis; George S. Sfyroeras; Konstantinos G. Moulakakis; Aristides Kallinis; Triantafillos G. Giannakopoulos; Christos D. Liapis

BACKGROUNDnThe effect of carotid artery stenting (CAS) on cognitive function in patients with extracranial carotid artery stenosis is equivocal. The aim of this study was to examine the impact of CAS on various domains of cognitive function.nnnMETHODSnWe performed a meta-analysis of the studies evaluating various domains of cognitive function before and after CAS, namely, (1) global cognition using Mini-Mental State Examination (MMSE) and Rey Auditory Verbal Learning Test (RAVLT), (2) executive function using Trail Making Test (TMT) A or Color Trails Test (CTT) A and TMT B or CTT B, (3) language ability using Boston Naming Test (BNT), (4) memory, (5) attention/psychomotor speed, and (6) functional ability, using various cognitive tests. Pooled weighted mean differences (WMDs) and standardized mean differences (SMDs) with 95% confidence intervals (95% CIs) were appropriately calculated using fixed or random effects models after assessing between-study heterogeneity. Meta-regression analysis was performed with number of patients per study; mean age (years); follow-up (months); proportion of men; proportion of patients with hypertension, diabetes mellitus, hyperlipidemia, smoking, and coronary artery disease; proportion of symptomatic patients; and degree of ipsilateral and degree of contralateral carotid stenosis as covariates.nnnRESULTSnSixteen studies were eligible, including a total of 626 CAS patients. A statistically significant improvement of global cognition was detected with MMSE (WMD = 0.67, 95% CI = 0.29-1.05, P < 0.001; follow-up = 5.6 months), but not with RAVLT (SMD = 0.45, 95% CI = -0.03 to 0.93, P = 0.07; follow-up = 2.4 months). Significant improvement of memory (SMD = 0.33, 95% CI = 0.11-0.55, P < 0.01; follow-up = 4.1 months) and attention/psychomotor speed (SMD = 0.21, 95% CI = 0.04-0.39, P = 0.02; follow-up = 4 months) was also detected. No statistically significant effect on executive function (TMT A/CTT A and TMT B/CTT B; SMD = 0.08, 95% CI = -0.10 to 0.26, P = 0.39; follow-up = 3.9 months and SMD = -0.02, 95% CI = -0.20 to 0.16, P = 0.82, respectively; follow-up = 3.9 months), language ability (BNT; SMD = 0.24, 95% CI = -0.05 to 0.54, P = 0.10; follow-up = 4 months), and functional ability (SMD = -0.05, 95% CI = -0.25 to 0.15, P = 0.63; follow-up = 3.8 months) was observed. No significant effects of the examined covariates were demonstrated in the meta-regression analyses.nnnCONCLUSIONSnCAS may be associated with improvement in global cognition, memory, and attention/psychomotor speed. There was no positive effect on executive function, language, and functional ability, but CAS was not associated with a decline in any area of cognitive function. Future studies in larger groups of patients are probably needed to fully investigate the long-term effect of CAS on cognition in patients with carotid artery stenosis.


Journal of Endovascular Therapy | 2015

Inflammatory Response and Renal Function Following Endovascular Repair of the Descending Thoracic Aorta

Konstantinos G. Moulakakis; George S. Sfyroeras; Anastasios Papapetrou; Constantine N. Antonopoulos; G. Mantas; John Kakisis; Maria Alepaki; Spyridon N. Mylonas; Petros Karakitsos; Christos D. Liapis

Purpose: To evaluate inflammatory response and renal function after thoracic endovascular aortic repair (TEVAR) of lesions in the descending thoracic aorta. Methods: Thirty-two consecutive patients treated with TEVAR from January 2010 to August 2013 were enrolled in this prospective study. Two were excluded owing to dissecting thoracic aortic aneurysm (TAA) extending into the renal arteries with renal failure in one and a saccular TAA in which a multilayer flow-modulating stent was implanted in the other. This left 30 patients (28 men; mean age 68.8±5.9 years) with 28 TAAs, an aortic dissection, and an aortic ulcer for the analysis. Temperature and serum levels of white blood cells (WBCs), C-reactive protein (CRP), interleukin-10 (IL-10), IL-6, IL-8, tumor necrosis factor-alpha (TNF-α), creatinine, urea, and cystatin C were measured preoperatively and at 24 and 48 hours postoperatively. Results: Statistically significant increases in temperature and serum levels of WBCs, CRP, IL-10, and IL-6 were observed 24 and 48 hours postoperatively compared to baseline (all p<0.05). The number of endografts and the coverage of the celiac or subclavian artery did not affect the magnitude of the inflammatory response. No significant differences were observed concerning serum levels of IL-8, TNF-α, creatinine, or cystatin C from baseline to 24 or 48 hours postoperatively. Conclusion: Endograft implantation in the thoracic aorta may propagate an inflammatory response during the early postoperative period. No clinical adverse events related to the increased inflammatory response were observed. Renal function does not seem to be deteriorated after TEVAR in the descending thoracic aorta.


Journal of Vascular Surgery | 2017

A network meta-analysis of randomized controlled trials comparing treatment modalities for de novo superficial femoral artery occlusive lesions

Constantine N. Antonopoulos; Spyridon N. Mylonas; Konstantinos G. Moulakakis; Theodoros N. Sergentanis; George S. Sfyroeras; Andreas M. Lazaris; John Kakisis; Spyros N. Vasdekis

Background: Treatment of superficial femoral artery (SFA) lesions remains challenging. We conducted a network meta‐analysis of randomized controlled trials aiming to explore the efficacy of treatment modalities for SFA “de novo” lesions. Methods: Eleven treatments for SFA occlusive disease were recognized. We used primary patency and binary restenosis at 12‐month follow‐up as proxies of efficacy for the treatment of SFA lesions. Results: A total of 33 studies (66 study arms; 4659 patients) were deemed eligible. In terms of primary patency, odds ratios (ORs) with 95% confidence intervals (CIs) were statistically significantly higher in drug‐eluting stent (DES; OR, 10.05; 95% CI, 3.22‐31.39), femoropopliteal bypass surgery (BPS; OR, 7.15; 95% CI, 2.27‐22.51), covered stent (CS; OR, 3.56; 95% CI, 1.33‐9.53), and nitinol stent (NS; OR, 2.83; 95% CI, 1.42‐5.51) compared with balloon angioplasty (BA). The rank order from higher to lower primary patency in the multidimensional scaling was DES, BPS, NS, CS, drug‐coated balloon, percutaneous transluminal angioplasty with brachytherapy, stainless steel stent, cryoplasty (CR), and BA. Combination therapy of NS with CR and drug‐coated balloon were the two most effective treatments, followed by NS, CS, percutaneous transluminal angioplasty with brachytherapy, cutting balloon, stainless steel stent, BA, and CR in terms of multidimensional scaling values for binary restenosis. Conclusions: DES has shown encouraging results in terms of primary patency for SFA lesions, whereas BPS still maintains its role as a principal intervention. On the contrary, BA and CR appear to be less effective treatment options.


Vascular | 2014

Epidemiology of concomitant injuries in traumatic thoracic aortic rupture: A meta-analysis

Constantine N. Antonopoulos; George S. Sfyroeras; Aristides Kallinis; John Kakisis; Christos D. Liapis; Eleni Petridou

Traumatic thoracic aortic rupture is a highly lethal injury. For those who arrive alive at the hospital, it is of utmost importance to quickly evaluate concomitant injuries and prioritize therapeutic interventions. We aimed to review the frequency of concomitant injuries in patients with thoracic aortic rupture, according to anatomic location and type of injury. A systematic literature search of six medical databases led to the identification of 90 publications; 27 categories of thoracic aortic rupture concomitant injuries were thereafter created. The respective pooled proportions and 95% confidence intervals were calculated and ranked in order of frequency. Among the 7258 patients studied, orthopedic fractures were the most frequent thoracic aortic rupture concomitant injury, amounting to a high pooled proportion of almost 70%, followed by thoracic injury in ∼50% and abdominal injury in over 40%. Pooled proportion for any type of head injury was also high (37%) pointing to the multiple-injury type of lesions among thoracic aortic rupture victims. Thoracic aortic rupture is a devastating injury, but rarely occurs as a sole traumatic entity. The recognition of concomitant thoracic, abdominal, head injuries and fractures after thoracic aortic rupture is of paramount importance. Future studies should focus on the impact of these injuries upon survival, morbidity and disability of multiple-injured thoracic aortic rupture patients.


Annals of Vascular Surgery | 2014

Association between Carotid Artery Occlusion and Ultrasonographic Plaque Type

Constantine N. Antonopoulos; George S. Sfyroeras; Konstantinos G. Moulakakis; Triantafillos G. Giannakopoulos; Ioannis Vassilopoulos; Anastasios Papapetrou; John Kakisis; Christos D. Liapis

BACKGROUNDnInternal carotid artery (ICA) occlusion is associated with acute stroke and carries significant morbidity and mortality. The aim of this study was to examine whether ultrasonographic carotid plaque type may be associated with ICA occlusion.nnnMETHODSnTwo hundred eleven patients (85% men, mean age 66.0±9.5 years, 28.9% asymptomatic) with ICA occlusion were included in this case-control study. Ultrasonographic Gray-Weale plaque type (I-IV, echolucent to echogenic) characterization was obtained in both the occluded and the contralateral ICA. Univariate and conditional logistic regression analyses with 1:1 pair matching per artery were undertaken. Each contralateral carotid artery with stenosis was treated as control to the ipsilateral-occluded ICA of the same patient.nnnRESULTSnA total of 261 ICAs (61.9%) were recorded with type I-II plaque, of which 165 (63.2%) were among the occluded and 96 (36.8%) were among the contralateral ICAs with stenosis (P<0.001). Mean contralateral ICA stenosis was 58.2%±20.4%. Regression analysis showed that carotid plaque type I-II was significantly associated with carotid artery occlusion compared with plaque type III-IV (crude odds ratio [OR]=4.29, 95% confidence intervals [CI]=2.81-6.57%, P<0.001, adjusted OR=5.60, 95% CI=3.23-9.70, P<0.001). Previous neurological events did not seem to be significantly associated with plaque echolucency (OR=0.62, 95% CI=0.29-1.35, P=0.23).nnnCONCLUSIONSnA significant association between echolucent plaque and ICA occlusion was observed. This observational hypothesis may prompt for further investigation of the causal mechanism between carotid plaque type and ICA occlusion by larger cohort studies.


Journal of Vascular Surgery | 2017

Safety and efficacy of polyurethane vascular grafts for early hemodialysis access

John Kakisis; Constantine N. Antonopoulos; G. Mantas; Evaggelos Alexiou; Konstantina Katseni; George S. Sfyroeras; Konstantinos G. Moulakakis; G. Geroulakos

Background: Arteriovenous grafts made of polyurethane (PU) have the advantage of early cannulation obviating the placement of a central vein catheter in patients with an acute need for long‐term hemodialysis. The aim of the present study was to evaluate the safety, efficacy and complication rate of PU vascular grafts for dialysis access in patients in whom early cannulation was performed. Methods: Between January 2007 and December 2015, 125 straight brachial‐axillary grafts were placed in patients with an acute thrombosis of a previous arteriovenous access. Sixty‐four were PU and 61 were polytetrafluoroethylene (PTFE) grafts. Patency and complications rates were compared between the two groups. Results: The median interval from implantation to cannulation was 1 day in the PU group vs 28 days in the PTFE group. Cumulative infection rate at 5 years was 13% and 8% in the PU and the PTFE groups, respectively (P = .6). None of the patients in the PU group developed a pseudoaneurysm necessitating intervention, compared with one patient in the PTFE group. Primary and secondary patency rates did not differ significantly between the two groups. The cumulative median primary patency was 23 months in the PU group vs 26 months in the PTFE group. Median secondary patency was 42 vs 33 months, respectively. Diabetes mellitus was the only factor adversely affecting graft patency in both groups. Conclusions: PU grafts offer the advantage of early cannulation with infection, pseudoaneurysm formation and patency rates similar to those of the PTFE grafts.


EFORT Open Reviews | 2018

Current concepts for the evaluation and management of diabetic foot ulcers

Andreas F. Mavrogenis; Panayiotis D. Megaloikonomos; Thekla Antoniadou; Vasilios G. Igoumenou; Georgios N. Panagopoulos; Leonidas Dimopoulos; Konstantinos G. Moulakakis; George S. Sfyroeras; Andreas C. Lazaris

The lifetime risk for diabetic patients to develop a diabetic foot ulcer (DFU) is 25%. In these patients, the risk of amputation is increased and the outcome deteriorates. More than 50% of non-traumatic lower-extremity amputations are related to DFU infections and 85% of all lower-extremity amputations in patients with diabetes are preceded by an ulcer; up to 70% of diabetic patients with a DFU-related amputation die within five years of their amputation. Optimal management of patients with DFUs must include clinical awareness, adequate blood glucose control, periodic foot inspection, custom therapeutic footwear, off-loading in high-risk patients, local wound care, diagnosis and control of osteomyelitis and ischaemia. Cite this article: EFORT Open Rev 2018;3:513-525. DOI: 10.1302/2058-5241.3.180010

Collaboration


Dive into the George S. Sfyroeras's collaboration.

Top Co-Authors

Avatar

Konstantinos G. Moulakakis

National and Kapodistrian University of Athens

View shared research outputs
Top Co-Authors

Avatar

John Kakisis

National and Kapodistrian University of Athens

View shared research outputs
Top Co-Authors

Avatar

Constantine N. Antonopoulos

National and Kapodistrian University of Athens

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Anastasios Papapetrou

National and Kapodistrian University of Athens

View shared research outputs
Top Co-Authors

Avatar

G. Geroulakos

National and Kapodistrian University of Athens

View shared research outputs
Top Co-Authors

Avatar

Maria Alepaki

National and Kapodistrian University of Athens

View shared research outputs
Top Co-Authors

Avatar

Petros Karakitsos

National and Kapodistrian University of Athens

View shared research outputs
Top Co-Authors

Avatar

Triantafillos G. Giannakopoulos

National and Kapodistrian University of Athens

View shared research outputs
Top Co-Authors

Avatar

Andreas M. Lazaris

National and Kapodistrian University of Athens

View shared research outputs
Researchain Logo
Decentralizing Knowledge