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

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Featured researches published by George S. Georgiadis.


Journal of Vascular Surgery | 2013

A meta-analysis of outcomes of endovascular abdominal aortic aneurysm repair in patients with hostile and friendly neck anatomy

George A. Antoniou; George S. Georgiadis; Stavros A. Antoniou; Ganesh Kuhan; David Murray

BACKGROUND An increasing number of abdominal aortic aneurysms with unfavorable proximal neck anatomy are treated with standard endograft devices. Skepticism exists with regard to the safety and efficacy of this practice. METHODS A systematic review of the literature was undertaken to identify all studies comparing the outcomes of endovascular aneurysm repair (EVAR) in patients with hostile and friendly infrarenal neck anatomy. Hostile neck conditions were defined as conditions that were not consistent with the instructions for use of the endograft devices employed in the selected studies. Outcome data were pooled, and combined overall effect sizes were calculated using fixed or random effects models. RESULTS Seven observational studies reporting on 1559 patients (hostile anatomy group, 714 patients; friendly anatomy group, 845 patients) were included. Patients with hostile anatomy required an increased number of adjunctive procedures to achieve proximal seal compared with patients with friendly anatomy (odds ratio [OR], 3.050; 95% confidence interval [CI], 1.884-4.938). Although patients with unfavorable neck anatomy had an increased risk of developing 30-day morbidity (OR, 2.278; 95% CI, 1.025-5.063), no significant differences in the incidence of type I endoleak and reintervention rates within 30 days of treatment between the two groups were identified (OR, 2.467 and 1.082; 95% CI, 0.562-10.823 and 0.096-12.186). Patients with hostile anatomy had a fourfold increased risk of developing type I endoleak (OR, 4.563; 95% CI, 1.430-14.558) and a ninefold increased risk of aneurysm-related mortality within 1 year of treatment (OR, 9.378; 95% CI, 1.595-55.137). CONCLUSIONS Insufficient high-level evidence for or against performing standard EVAR in patients with hostile neck anatomy exists. Our analysis suggests EVAR should be cautiously used in patients with anatomic neck constraints.


European Journal of Vascular and Endovascular Surgery | 2009

Lower-extremity Arteriovenous Access for Haemodialysis: A Systematic Review

G.A. Antoniou; Miltos K. Lazarides; George S. Georgiadis; Sfyroeras Gs; Evagelos S. Nikolopoulos; Athanasios D. Giannoukas

BACKGROUND The lower extremity is increasingly used as an access site in end-stage renal disease patients. However, reports present conflicting results, creating confusion regarding the feasibility and outcomes. Our objective is to review the available literature and analyse the patency rates and complications of various types of lower-extremity arteriovenous access. METHODS An Internet-based literature search was performed using MEDLINE to identify all published reports on lower-extremity vascular access. The analysis involved studies comprising at least 10 arteriovenous accesses with both inflow and outflow vessels in the lower extremity, and reporting on patency rates and access-related complications. The weighted mean patency rates were calculated, and the chi-square (chi(2)) test was used to evaluate the differences in the complication rates in the subgroups of patients identified. RESULTS Three main types of lower-extremity vascular access were identified: the upper thigh prosthetic, the mid-thigh prosthetic and the femoral vein transposition arteriovenous access. There are limited data on saphenous vein loop grafts, which report poor results. The weighted mean primary patency rates at 12 months were 48%, 43% and 83%, respectively. The weighted mean secondary patency rates at 12 months were 69%, 67% and 93%, respectively. Access loss as a result of infection was more common in upper thigh and mid-thigh grafts than femoral vein transposition arteriovenous access (18.40%, 18.33% vs. 1.61%; P<0.05). Ischaemic complications rates were higher in autologous than prosthetic arteriovenous access (20.97% vs. 7.18%, P<0.05). CONCLUSIONS Lower-extremity vascular access has acceptable results in terms of patency, with femoral vein transposition having better patency rates than femoral grafts. Autologous access is associated with less infective complications, however, at the expense of increased ischaemic complications rates. Further research with randomised trials is required to assess the outcomes of lower-extremity vascular access.


Journal of Vascular Surgery | 2013

Endovascular repair for ruptured abdominal aortic aneurysm confers an early survival benefit over open repair

George A. Antoniou; George S. Georgiadis; Stavros A. Antoniou; Polyvios Pavlidis; Dimitrios Maras; George S. Sfyroeras; Efstratios Georgakarakos; Miltos K. Lazarides

BACKGROUND Despite the intuitive advantages of endovascular repair (EVAR) of ruptured abdominal aortic aneurysms (AAAs), uncertainty remains about the optimal management in the absence of convincing high-quality evidence. Our objective was to undertake a comprehensive literature review and perform a meta-analysis of outcome data of treatment modalities for ruptured AAAs. METHODS Systematic searches were conducted of electronic information sources to identify studies comparing perioperative outcomes of EVAR and open repair for AAA rupture. Summary estimates of odds ratios (ORs) or standardized mean difference and 95% confidence intervals (CIs) were obtained with a random-effects model. Meta-regression models were formed to explore potential heterogeneity as a result of changes in practice over time. RESULTS We selected 41 studies for analysis. The entire meta-analysis population comprised 59,941 patients (8201 EVAR patients and 51,740 open repair patients). EVAR was associated with a significantly lower incidence of in-hospital mortality (OR, 0.56; 95% CI, 0.50-0.64; P < .01; meta-analysis of risk-adjusted observational studies and randomized controlled trials: OR, 0.58; 95% CI, 0.46-0.73; P < .01). EVAR patients had a significantly decreased risk of developing respiratory complications (OR, 0.59; 95% CI, 0.49-0.69; P < .01) and acute renal failure (OR, 0.65; 95% CI, 0.55-0.78; P < .01) and a trend toward a reduced incidence of cardiac complications (OR, -0.02; 95% CI, -0.03 to 0.00; P = .05) and mesenteric ischemia (OR, 0.66; 95% CI, 0.44-1.00; P = .05). Patients treated with EVAR had significantly less requirements of intraoperative blood transfusion (standardized mean difference, -0.88; 95% CI, -1.06 to -0.70; P < .01). Random-effects meta-regression revealed no statistical evidence for an association between death and year of publication (P = .19). CONCLUSIONS Our analysis provides evidence to motivate the adoption of an EVAR-first policy in a nonelective setting and the establishment of standardized protocols for the management ruptured AAAs.


Journal of Vascular Surgery | 2013

A meta-analysis of endovascular versus surgical reconstruction of femoropopliteal arterial disease.

George A. Antoniou; Nicholas Chalmers; George S. Georgiadis; Miltos K. Lazarides; Stavros A. Antoniou; Ferdinand Serracino-Inglott; J. Vincent Smyth; David Murray

BACKGROUND Controversy exists as to the relative merits of surgical and endovascular treatment of femoropoliteal arterial disease. METHODS A systematic review of the literature was undertaken to identify studies comparing open surgical and percutaneous transluminal methods for the treatment of femoropopliteal arterial disease. Outcome data were pooled and combined overall effect sizes were calculated using fixed or random effects models. RESULTS Four randomized controlled trials and six observational studies reporting on a total of 2817 patients (1387 open, 1430 endovascular) were included. Endovascular treatment was accompanied by lower 30-day morbidity (odds ratio [OR], 2.93; 95% confidence interval [CI], 1.34-6.41) and higher technical failure (OR, 0.10; 95% CI, 0.05-0.22) than bypass surgery, whereas no differences in 30-day mortality between the two groups were identified (OR, 0.92; 95% CI, 0.55-1.51). Higher primary patency in the surgical treatment arm was found at 1 (OR, 2.42; 95% CI, 1.37-4.28), 2 (OR, 2.03; 95% CI, 1.20-3.45), and 3 (OR, 1.48; 95% CI, 1.12-1.97) years of intervention. Progression to amputation was found to occur more commonly in the endovascular group at the end of the second (OR, 0.60; 95% CI, 0.42-0.86) and third (OR, 0.55; 95% CI, 0.39-0.77) year of intervention. Higher amputation-free and overall survival rates were found in the bypass group at 4 years (OR, 1.31; 95% CI, 1.07-1.61 and OR, 1.29; 95% CI, 1.04-1.61, respectively). CONCLUSIONS High-level evidence demonstrating the superiority of one method over the other is lacking. An endovascular-first approach may be advisable in patients with significant comorbidity, whereas for fit patients with a longer-term perspective a bypass procedure may be offered as a first-line interventional treatment.


Journal of Vascular Surgery | 2011

Early results of the Endurant endograft system in patients with friendly and hostile infrarenal abdominal aortic aneurysm anatomy

George S. Georgiadis; George Trellopoulos; George A. Antoniou; Konstantinos Gallis; Evagelos S. Nikolopoulos; Konstantinos C. Kapoulas; Xanthi Pitta; Miltos K. Lazarides

OBJECTIVE To evaluate and compare the outcome after endovascular abdominal aortic aneurysm repair (EVAR) with the newly released Endurant endograft system in patients with different aortoiliac anatomic characteristics. METHODS We conducted a prospective observational study assigning patients with infrarenal abdominal aortic aneurysm (AAA) treated with the Endurant endoprosthesis from February 2009 to March 2010. Two groups were studied, according to the presence of a friendly (group I [GI] = 43) or hostile (group II [GII] = 34) infrarenal aortoiliac anatomy. Hostile profile was defined as any (or combination) of the following measurements: 5 mm ≤ proximal neck length (Lpr) ≤ 12 mm, 60° < proximal neck angle (A°pr) ≤ 90° and 60° < any iliac axis angle (A°iliac) ≤ 90°. Primary end points included technical and clinical success, freedom from early or late secondary interventions, any type of endoleak, and aneurysm-related death. All outcome measures were calculated using the Kaplan-Meier method and the log rank test was applied for comparisons between the groups. RESULTS The mean comorbid severity scoring was higher in GII (P = .018). The mean follow-up period in GI and GII was 12.9 ± 3.9 months (± SD, range: 6.4-19.8) and 12.4 ± 4 months (range: 4.2-19.6), respectively. Two unplanned conversions to aortouniiliac configurations were required in GI. The technical success rate in GI and GII was 95.4% and 100%, respectively. The requirement for intentional occlusion of the internal iliac artery, the requirement for cross-limb technique, the necessity of troubleshooting techniques, the procedure and radiation times, the frequency of postimplantation syndrome, and mean hospital stay were significantly higher in GII (P = .028, P = .013, P = .005, P = .037, P < .001, P = .032, P = .021, respectively). Two patients of GI died in the early postoperative period (one aneurysm but not device-related death), whereas no deaths in GII were recorded, yielding an overall 30-day mortality rate of 2.3%. No type I/III endoleaks were recorded up to the end of the study. Freedom from any type of endoleak, early or late secondary interventions, and aneurysm-related death at 12 months were found in 93.2%, 87.1%, and 93.3% of GI patients; respective values for GII were 86% (P = .21), 93.4% (P = .066), and 93.4%. The clinical success rate was 82.1% and 100% at 12 months for GI and GII, respectively. CONCLUSIONS Early (12 months) results suggest similar clinical performance of the Endurant stent graft system in endovascular treatment of AAAs with friendly and hostile anatomies, however, demonstrating more intra- and perioperative adversities for the last group. Larger prospective studies or even randomized trials comparing different new generation graft models are required to evaluate the comparable long-term results and possible expansion of EVAR indications for this specific endograft in adverse anatomies.


The International Journal of Lower Extremity Wounds | 2006

Diagnostic Criteria and Treatment of Buerger’s Disease: A Review

Miltos K. Lazarides; George S. Georgiadis; Theophanis T. Papas; Evagelos S. Nikolopoulos

Buerger’s disease is an inflammatory occlusive disorder affecting the small and medium-size arteries and veins of young, predominately male, smokers. The disorder has been identified as an autoimmune response triggered when nicotine is present. Tobacco abuse is the major contributing risk factor; however, smoking seems to be a synergistic factor rather than the cause of the disease. The traditional diagnosis of Buerger’s disease is based on 5 criteria (smoking history, onset before the age of 50 years, infrapopliteal arterial occlusive disease, either upper limb involvement or phlebitis migrans, and absence of atherosclerotic risk factors other than smoking). As there is no specific diagnostic test and an absence of positive serologic markers, confident clinical diagnosis should be made only when all these 5 criteria have been fulfilled although not universally accepted. The angiographic findings in Buerger’s disease (“corkscrew,” “spider legs,” or “tree roots”) are helpful but not pathognomonic. A wide spectrum of medical or surgical therapeutic options have been proposed; however, total abstinence from tobacco use remains the only means of stopping the disease progression. The initial management of patients with Buerger’s disease should be conservative. Because several arteries may be unaffected, claudicants should be encouraged to walk, whereas patients with “critical” ischemia should be admitted for bed rest in the hospital. Bypass grafting is seldom an option, as the location of the lesions distally leaves little to bypass because of lack of target vessels. A literature review revealed only a few series reporting vascular reconstruction (mainly femorodistal bypasses) in Buerger’s disease. Bypass patency rates were suboptimal; however, the corresponding limb salvage rates were satisfactory. A possible explanation is that patent grafts, even over a short period of time, are sufficient to allow healing of ulcers in patients with Buerger’s disease.


Journal of Endovascular Therapy | 2015

Late Rupture of Abdominal Aortic Aneurysm After Previous Endovascular Repair: A Systematic Review and Meta-analysis.

George A. Antoniou; George S. Georgiadis; Stavros A. Antoniou; Simon Neequaye; John A. Brennan; Francesco Torella; S. Rao Vallabhaneni

Purpose: To report a systematic literature review of late rupture of abdominal aortic aneurysm (AAA) after endovascular aneurysm repair (EVAR) and the results of a pooled analysis of causes, treatment, and outcomes. Methods: Electronic information sources and bibliographic reference lists were interrogated using a combination of free text and controlled vocabulary searches; 11 articles were ultimately identified that fulfilled the inclusion criteria. The articles reported a total of 190 patients who were included in the qualitative and quantitative synthesis. Mortality within 30 days or during the admission with aneurysm rupture was a primary endpoint; major perioperative morbidity was a secondary endpoint. A meta-analysis was performed for 30-day/in-hospital mortality using the random effects model. Results: A total of 152 ruptures occurred after 16,974 EVAR procedures reported by 8 of the case series, giving an incidence of 0.9% [95% confidence interval (CI) 0.77 to 1.05]. The mean time to rupture was 37 months. Twenty-nine percent (95% CI 20 to 39) of the patients had at least one previous secondary endovascular intervention following the initial EVAR, and 37% (95% CI 30 to 45) were not compliant with surveillance. Type I and III endoleaks were the predominant causes of rupture. Open surgical treatment was undertaken in 61% (95% CI 53 to 68) of the patients who underwent treatment. The pooled estimate for perioperative mortality was 32% (95% CI 24 to 41). A significantly lower mortality was found with endovascular treatment than open surgical management (p=0.027). Conclusion: Graft-related endoleaks appear to be the predominant causes of late aneurysm rupture. Quality of and compliance with post-EVAR surveillance are important factors in late rupture; a large proportion of late ruptures are amenable to endovascular treatment.


Perspectives in Vascular Surgery and Endovascular Therapy | 2012

Epidermal Growth Factor in the Treatment of Diabetic Foot Ulcers An Update

Elisavet K. Tiaka; Nikolaos Papanas; Anastassios C. Manolakis; George S. Georgiadis

Management of diabetic foot ulcers remains a rather challenging task. Epidermal growth factor (EGF) plays a central role in wound healing. It acts on epithelial cells and fibroblasts promoting restoration of damaged epithelium. However, its bioavailability is impaired in chronic diabetic foot ulcers. Current evidence suggests that application of human recombinant EGF in addition to standard treatment is able to achieve both partial and complete healing and to prevent foot amputations. Its efficacy has been tested at various concentrations and by various administration routes (topical application and intralesional injection). Intralesional injection has better availability on the deep wound layers, but pain at the injection site is a common complaint. Generally, adverse events have been minor to mild. Finally, numerous issues need to be further clarified before widespread use of EGF becomes possible in everyday practice. Such issues include optimal dosage and administration route, characteristics of the ulcers most likely to heal (severity and ischemic/neuropathic or both), and cost-effectiveness.


Journal of Endovascular Therapy | 2011

A meta-analysis of outcome after percutaneous endovascular aortic aneurysm repair using different size sheaths or endograft delivery systems

George S. Georgiadis; George A. Antoniou; Miltos Papaioakim; Efstratios Georgakarakos; George Trellopoulos; Nikolaos Papanas; Miltos K. Lazarides

Purpose To determine via a meta-analysis if the success rates for percutaneous EVAR using the “preclose” technique with suture-mediated vascular closure devices (SMCDs) are higher for smaller sheaths [≤18-F outer diameter (OD)] than for larger sheaths (≥20-F). Methods All English-language studies on percutaneous EVAR outcomes related to sheath sizes published between 1999 and August 30, 2010, were searched using MEDLINE and SCOPUS. Randomized trials, retrospective or prospective observational studies, and original articles (including a review) were included. The search identified 32 relevant full-text studies; data on percutaneous EVAR outcomes per sheath size category (≤18-F and ≥20-F OD) were included in the final meta-analysis of data from 17 studies (1 randomized controlled trial and 8 retrospective and 8 prospective cohort observational studies). The final analysis included 1440 patients and 2447 femoral access sites. Primary success was defined as closure of a common femoral artery arteriotomy without the need for any adjunctive surgical or endovascular procedure. Results Pooled data revealed that success rates were significantly better when percutaneous EVAR was performed with ≤18-F sheaths than with ≥20-F sheaths (odds ratio 1.78, 95% confidence interval 1.24 to 2.54, p=0.002). This benefit, although not significant, was more pronounced when multiple rather than single pre-applied SMCDs were deployed (odds ratio 2.16 vs. 1.64, respectively; p=0.353). Conclusion When considering primary success, it appears that larger-bore femoral access sheaths (≥20-F) introduced for percutaneous EVAR after pre-application of SMCDs are predictors of primary failure and the need for conversion to a femoral cutdown. More advanced large-bore SMCDs are required to further reduce the necessity for conversion. Planned use of multiple SMCDs might be more beneficial when ≤18-F sheaths are required.


JAMA Surgery | 2013

Meta-analysis and Meta-Regression Analysis of Outcomes of Carotid Endarterectomy and Stenting in the Elderly

George A. Antoniou; George S. Georgiadis; Efstratios Georgakarakos; Stavros A. Antoniou; Nikos Bessias; John Vincent Smyth; David Murray; Miltos K. Lazarides

IMPORTANCE Uncertainty exists about the influence of advanced age on the outcomes of carotid revascularization. OBJECTIVE To undertake a comprehensive review of the literature and conduct an analysis of the outcomes of carotid interventions in the elderly. DESIGN AND SETTING A systematic literature review was conducted to identify articles comparing early outcomes of carotid endarterectomy (CEA) or carotid stenting (CAS) in elderly and young patients. MAIN OUTCOMES AND MEASURES Combined overall effect sizes were calculated using fixed or random effects models. Meta-regression models were formed to explore potential heterogeneity as a result of changes in practice over time. RESULTS Our analysis comprised 44 studies reporting data on 512,685 CEA and 75,201 CAS procedures. Carotid stenting was associated with increased incidence of stroke in elderly patients compared with their young counterparts (odds ratio [OR], 1.56; 95% CI, 1.40-1.75), whereas CEA had equivalent cerebrovascular outcomes in old and young age groups (OR, 0.94; 95% CI, 0.88-0.99). Carotid stenting had similar peri-interventional mortality risks in old and young patients (OR, 0.86; 95% CI, 0.72-1.03), whereas CEA was associated with heightened mortality in elderly patients (OR, 1.62; 95% CI, 1.47-1.77). The incidence of myocardial infarction was increased in patients of advanced age in both CEA and CAS (OR, 1.64; 95% CI, 1.57-1.72 and OR, 1.30; 95% CI, 1.16-1.45, respectively). Meta-regression analyses revealed a significant effect of publication date on peri-interventional stroke (P = .003) and mortality (P < .001) in CAS. CONCLUSIONS AND RELEVANCE Age should be considered when planning a carotid intervention. Carotid stenting has an increased risk of adverse cerebrovascular events in elderly patients but mortality equivalent to younger patients. Carotid endarterectomy is associated with similar neurologic outcomes in elderly and young patients, at the expense of increased mortality.

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Miltos K. Lazarides

Democritus University of Thrace

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Efstratios Georgakarakos

Democritus University of Thrace

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George A. Antoniou

Pennine Acute Hospitals NHS Trust

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Christos Argyriou

Democritus University of Thrace

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Nikolaos Schoretsanitis

Democritus University of Thrace

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Evagelos S. Nikolopoulos

Democritus University of Thrace

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Nikolaos Papanas

Democritus University of Thrace

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Konstantinos C. Kapoulas

Democritus University of Thrace

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David Murray

Central Manchester University Hospitals NHS Foundation Trust

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