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Dive into the research topics where Christos D. Karkos is active.

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Featured researches published by Christos D. Karkos.


Laryngoscope | 2009

Lemierre's syndrome: A systematic review.

Peter D. Karkos; Sheetal Asrani; Christos D. Karkos; Samuel C. Leong; Evangelia G. Theochari; Thalia D. Alexopoulou; Assimakis D. Assimakopoulos

Lemierres syndrome is characterized by a history of recent oropharyngeal infection, clinical or radiological evidence of internal jugular vein thrombosis, and isolation of anaerobic pathogens, mainly Fusobacterium necrophorum. It was once called the forgotten disease because of its rarity, but it may not be that uncommon after all. This review aims to provide physicians with an update on the etiology, management, and prognosis of Lemierres syndrome.


Experimental and Clinical Endocrinology & Diabetes | 2009

Visfatin (Nampt) and Ghrelin as Novel Markers of Carotid Atherosclerosis in Patients with Type 2 Diabetes

Nikolaos P.E. Kadoglou; N. Sailer; A. Moumtzouoglou; Alkistis Kapelouzou; H. Tsanikidis; I. Vitta; Christos D. Karkos; P. E. Karayannacos; T. Gerasimidis; Christos D. Liapis

OBJECTIVE Visfatin (nampt) and ghrelin are the most recently identified adipocytokines, but their role in atherosclerosis is poorly clarified. In our study we investigated their association with advanced carotid atherosclerosis and carotid intima-media thickness (CIMT) in patients with type 2 diabetes mellitus (T2DM). METHODS 122 patients (50 males) with T2DM, aged 55-70 were enrolled. Sixty-four age- and sex-matched healthy individuals served as controls (group A). CIMT was assayed in all participants by ultrasound. Among diabetic patients, 47 appeared with carotid plaques (group B), while 75 without plaques (group C). Anthropometric parameters, blood pressure, glycemic and lipid profile, high-sensitivity CRP (hsCRP), insulin resistance (HOMA-IR), fibrinogen, nampt and ghrelin were measured. RESULTS Diabetic patients had a higher mean-CIMT, increased body-mass index, worse lipid profile, elevated blood pressure and higher levels of white blood cells count, nampt and hsCRP with respect to controls (p<0.01). Among diabetic patients, groups B and C were comparable in anthropometric, glycemic and lipid parameters. Serum nampt was significantly higher in group B rather than in groups A and C (p<0.05). On the other hand, ghrelin levels were considerably lower only in diabetic patients with carotid atherosclerosis compared with healthy individuals. In univariate analysis, mean-CIMT correlated with age (r=0.312; p=0.003), nampt (r=0.341; p<0.001) and ghrelin (r=-0.421; p=0.002) and the latter associations remained significant in multiple regression analysis. CONCLUSIONS High nampt and low ghrelin serum levels are significantly associated with advanced carotid atherosclerosis in patients with T2DM. Moreover these adipocytokines are independently associated with CIMT, implicating their role as novel atherosclerotic biomarkers and providing another important link between adiposity and atherosclerosis.


Archives of Surgery | 2009

Mortality After Endovascular Repair of Ruptured Abdominal Aortic Aneurysms A Systematic Review and Meta-analysis

Christos D. Karkos; Denis W. Harkin; Andry Giannakou; Thomas S. Gerassimidis

OBJECTIVE To document mortality after endovascular repair of ruptured abdominal aortic aneurysms (RAAAs). DATA SOURCES MEDLINE and EMBASE databases. STUDY SELECTION Articles that reported data on mortality after endovascular repair of RAAAs were identified. Only patients with true ruptures were included. Additionally, information on mortality after concurrent open repair was sought. DATA EXTRACTION One of the authors reviewed all of the studies and extracted appropriate data. A total of 43 articles were identified, 14 of which were excluded. DATA SYNTHESIS Twenty-nine articles with 897 patients who underwent endovascular repair met the inclusion criteria. Of the patients with available information, 86% were men; 29% had been operated on under local anesthesia; 28% were hemodynamically unstable; 17% required intra-aortic balloon occlusion; 48% received bifurcated stent grafts; 6% had endovascular procedures converted to open repair intraoperatively; and 5.5% developed abdominal compartment syndrome. In-hospital and/or 30-day mortality ranged between 0% and 54% in different series, whereas the pooled mortality after endovascular repair was 24.5% (95% confidence interval [CI], 19.8%-29.4%). In 19 studies reporting results of both endovascular and concurrent open repair from the same unit, the pooled mortality after open repair was 44.4% (95% CI, 40.0%-48.8%), and the pooled overall mortality for RAAA undergoing endovascular or open repair was 35% (95% CI, 30%-41%). CONCLUSIONS Endovascular repair of RAAAs is associated with acceptable mortality rates. Additional studies will be required to verify these promising results and precisely define the role of endovascular treatment as an additional therapeutic option for RAAAs.


Journal of Vascular Surgery | 2014

A systematic review and meta-analysis of abdominal compartment syndrome after endovascular repair of ruptured abdominal aortic aneurysms

Christos D. Karkos; Georgios Menexes; Nikolaos Patelis; Thomas E. Kalogirou; Ioakeim T. Giagtzidis; Denis Harkin

OBJECTIVE Limited data exist regarding the development of abdominal compartment syndrome (ACS) after endovascular repair of ruptured abdominal aortic aneurysms (RAAAs). We aimed to record the incidence, management, and outcome of this complication. METHODS A systematic review and meta-analysis of the English language literature was undertaken through June 2012. Articles reporting data on outcome after endovascular repair of RAAAs were identified, and information regarding ACS was sought. RESULTS Included were 39 eligible studies reporting 1134 patients. The pooled perioperative mortality was 21% (95% confidence interval [CI], 18%-24%). A total of 109 cases of ACS were recorded. There was significant within-study heterogeneity (Cochran Q = 94.1; P < .0001), and the pooled ACS rate was 8% (95% CI, 5.6%-10.8%). Only six studies accurately defined ACS, and four focused specifically on ACS. When the meta-analysis was repeated after including only studies with a definition and those focusing on ACS, the pooled rate increased to 17% (95% CI, 10%-26%) and 21% (95% CI, 13%-30%), respectively. A random-effects meta-regression analysis investigating the effect of ACS and other risk factors on mortality revealed a significant linear correlation between hemodynamic instability and death (r = 0.303) and a nonlinear (second degree polynomial) association between bifurcated endograft approach and death (R(2) = 0.348; P = .0027). However, no statistically significant association could be found between ACS and death. A further meta-regression analysis failed to identify any statistically significant predictors of ACS. Treatment included open decompression in 86 patients, percutaneous drainage in 18 (catheter only in five, combined with tissue plasminogen activator infusion in 13), and conservative measures in five. Data on outcome of ACS were only available for 76 patients; 35 of these died, for a mortality rate of 47%. CONCLUSIONS The pooled ACS rate was calculated at 8%, but this figure may be >20% with improved awareness and vigilant monitoring. Although no statistically significant association could be found between ACS and death, almost half the patients who developed ACS after endovascular repair of RAAAs were likely to die.


Journal of Vascular Surgery | 2008

Usefulness of the Hardman index in predicting outcome after endovascular repair of ruptured abdominal aortic aneurysms

Christos D. Karkos; Dimitrios Karamanos; Konstantinos O. Papazoglou; Alexandros S. Kantas; Evangelia G. Theochari; Apostolos Kamparoudis; Thomas S. Gerassimidis

OBJECTIVES The Hardman index, which has five variables, has been recommended as a predictor of outcome after open repair of ruptured abdominal aortic aneurysms (RAAAs). It has been reported that the presence of three or more variables is uniformly fatal. The aim of this study was to test the same model in an independent series of RAAA patients undergoing endovascular repair. METHODS A consecutive series of 41 patients undergoing endovascular repair for RAAA during an 8-year period was analyzed retrospectively. Thirty-day mortality and patient variables, including the five Hardman risk factors of age >76 years, serum creatinine >190 micromol/L, hemoglobin <9 g/dL, loss of consciousness, and electrocardiographic (ECG) evidence of ischemia, were recorded. The Hardman index and a revised version of the index with four variables (without ECG ischemia) were calculated and related to clinical outcome. RESULTS Operative mortality was 41% (17 of 41). On univariate analysis, only age >76 years (P = .01) and the use of local anesthesia (P < .0001) were statistically significant. Loss of consciousness (P = .05) showed a trend toward a higher mortality, albeit not statistically significant. On multivariate analysis, the use of local anesthesia was the only significant predictor of survival (odds ratio [OR], 0.03; 95% confidence interval [CI], 0.003-0.25, P = .001). Again, loss of consciousness showed an association with a higher chance of dying but did not achieve statistical significance (OR, 6.30; 95% CI, 0.93-42.51, P = .059). The original and revised versions of the Hardman index were both significantly associated with death (P = .02 and P = .001, chi(2) test for trend). The cumulative effect of 0, 1, 2, and >/=3 risk factors on mortality was 0%, 27%, 36%, and 71% for the original index, and 12.5%, 21%, 60%, and 78% for the revised version, respectively. Four and two patients with a score of >/=3 in each version of the index survived endovascular repair. CONCLUSIONS The Hardman index, with or without incorporating ECG ischemia, seems to be a simple and useful predictive tool in patients undergoing endovascular repair of RAAA, with the mortality rate increasing along with the Hardman score. However, the index cannot be used to accurately identify patients with no chance of survival after endovascular repair.


Vascular and Endovascular Surgery | 2009

Cerebral Hyperperfusion After Carotid Stenting: A Transcranial Doppler and SPECT Study

Giorgos S. Sfyroeras; Christos D. Karkos; Georgios Arsos; Charalampos Liasidis; Athanassios S. Dimitriadis; Konstantinos O. Papazoglou; Thomas S. Gerassimidis

Aim: To document the incidence of symptomatic cerebral hyperperfusion after carotid stenting and to determine possible predisposing factors. Methods: A prospective study of 29 consecutive patients undergoing carotid stenting. All patients underwent 1) brain computed tomography scan and magnetic resonance imaging, 2) transcranial Doppler including assessment of cerebrovascular reactivity of the ipsilateral middle cerebral artery and 3) 99m hexamethyl-propyleneamine oxime brain single photon emission computed tomography, before and after the procedure. Results: A total of 5 patients developed adverse neurological events, 4 of them transient. Cerebral hyperperfusion was documented in two of these (6.9%). Both had exhausted cerebrovascular reactivity in the preoperative transcranial Doppler examination. No consistent pattern of interhemispheric asymmetry in brain perfusion was found in these patients. Conclusions: Symptomatic cerebral hyperperfusion is not uncommon after carotid stenting. There seems to be a link between exhausted cerebrovascular reactivity of the ipsilateral middle cerebral artery and increased risk of cerebral hyperperfusion.


Journal of Endovascular Therapy | 2006

Interhemispheric asymmetry in brain perfusion before and after carotid stenting: a 99mTc-HMPAO SPECT study.

Giorgos S. Sfyroeras; Georgios Arsos; Christos D. Karkos; Charalampos Liasidis; Charalampos Spyridis; Dimitrios Boundas; Athanasios Dimitriadis; Thomas S. Gerassimidis

Purpose: To assess the effect of unilateral carotid angioplasty and stenting (CAS) on cerebral perfusion asymmetry in patients with severe extracranial carotid stenosis by means of technetium Tc 99m hexamethyl-propyleneamine oxime brain single photon emission computed tomography (99mTc-HMPAO SPECT). Methods: Twenty-nine consecutive patients (22 men; median age 68 years, range 58–80; 13 symptomatic) undergoing unilateral CAS were included in the study. Brain perfusion was assessed by 99mTc-HMPAO brain SPECT prior to the procedure and postoperatively at 8 hours and at 2 to 4 months. The asymmetry index (AI), a measure of the interhemispheric asymmetry in perfusion, was calculated as [(counts in “healthy” hemisphere—counts in hemisphere with carotid stenosis)/counts in “healthy” hemisphere]x100. Results: The preoperative AI demonstrated a wide variation (mean −0.5%±8.4%, range −19.5% to 14.1%). There was no significant correlation between the degree of carotid stenosis and preoperative AI. The mean preoperative AI in the asymptomatic patients was lower than in the symptomatic group [-4.0%±8.5% (range −19.5% to 8.2%) versus 3.8%±6.4% (range −5.2% to 14.1%), p=0.01], suggesting reduced perfusion of the ipsilateral cerebral hemisphere compared to the contralateral side in symptomatic patients. AI variation did not improve after CAS; there was no difference in AI among the 3 SPECT studies (p=0.75). Preoperative AI correlated significantly with late AI (r=0.74, p<0.0001); however, there was no statistically significant correlation between immediate postoperative AI and either preoperative (r=0.24, p=0.217) or late (r=0.24, p=0.249) AI. Conclusion: Asymmetry in cerebral perfusion in patients with severe extracranial carotid atherosclerosis does not correlate with the degree of carotid stenosis. Symptomatic patients demonstrate compromised perfusion of the ipsilateral hemisphere compared to asymptomatic patients. As judged by 99mTc-HMPAO SPECT scanning, cerebral perfusion patterns do not significantly change after CAS.


Vascular and Endovascular Surgery | 2004

Erectile dysfunction after open versus angioplasty aortoiliac procedures: a questionnaire survey.

Christos D. Karkos; Angela Wood; Iain Bruce; Petros D. Karkos; Mohamed Baguneid; Mark E. Lambert

Erectile dysfunction (ED) is a common complication after aortoiliac surgery. The aims of this study were to determine the incidence of ED in patients with aortoiliac occlusive disease or aneurysm and evaluate the effect of revascularization by means of open surgery or iliac angioplasty/stenting upon erectile function by using the new International Index of Erectile Function (IIEF) questionnaire. All male patients who had previously undergone open aortoiliac reconstruction or iliac angioplasty/stenting and who were alive at the time of this study were first contacted by telephone. Those who agreed to take part in the study were sent anonymous IIEF questionnaires. Patients were asked to recall their sexual function before and 3 months after the procedure. ED was defined as IIEF score of <11. After telephone interview, a total of 116 patients agreed to take part in the study. The response rate was 61%. Two patients, one in each group, had ED preoperatively. The preoperative IIEF scores were no different in surgery and angioplasty/stenting groups (p=0.3). Overall, 46/63 patients reported worsening erectile function postoperatively. In the surgery group (n=37), 32 patients reported deterioration of their sexual function, 3 no change, and 2 improvement, while in the angioplasty/stenting group (n=26), 14 patients had deterioration, 11 no change, and 1 improvement. In both groups, the IIEF score decreased significantly postintervention; however, the deterioration was much more pronounced after open surgery (p<0.001). Of the 61 patients with “normal” erectile function (IIEF= 11), 10 patients (28%) developed ED following surgery, but none after angioplasty/ stenting (p=0.003). As judged by the IIEF, a significant proportion of patients undergoing open and endovascular procedures experience worsening sexual function.


Interactive Cardiovascular and Thoracic Surgery | 2013

Can an accessory renal artery be safely covered during endovascular aortic aneurysm repair

George A. Antoniou; Christos D. Karkos; Stavros A. Antoniou; George S. Georgiadis

A best evidence topic was constructed according to a structured protocol. The question addressed was whether coverage of an accessory renal artery (ARA) in patients undergoing endovascular aortic aneurysm repair (EVAR) is associated with increased risk of renal impairment. Altogether, 106 papers were located using the reported searches, of which 5 represented the best evidence to answer the question. The authors, journal, date and country of publication, study type, patient group studied, relevant outcomes parameters and results of these papers are tabulated. Our best evidence analysis included 116 patients who had one or more ARA excluded during EVAR. Segmental renal infarction occurred in varying numbers of patients (ranging from 0 to 84%). The authors consistently demonstrate that loss of renal mass is not associated with functional renal impairment, expressed by various outcome parameters such as serum creatinine, glomerular filtration rate (GFR), renal failure requiring dialysis and worsening hypertension. Comparisons of groups of patient with covered or preserved ARAs by one of the selected studies showed no difference in any of these renal outcome parameters, apart from a significantly higher renal infarct volume in the former group (P < 0.001). Subgroup analysis of patients with pre-existing renal dysfunction (GFR < 60 ml/h/m(2)) showed no difference in GFR change when comparing covered with uncovered ARA patient cohorts. No type II endoleak related to the covered ARA was reported in any of these studies. In conclusion, current evidence supports the safety of coverage of ARAs located in the proximal fixation zone to achieve seal in EVAR.


American Journal of Emergency Medicine | 2010

Axillary artery transection after recurrent anterior shoulder dislocation.

Christos D. Karkos; Dimitrios Karamanos; Konstantinos O. Papazoglou; D. Papadimitriou; Neophytos Zambas; Ioannis N. Gerogiannis; Thomas S. Gerassimidis

Axillary artery transection after recurrent anterior shoulder dislocation is extremely rare. We present 2 such patients. The first, a 62-year-old man, presented with acute ischemia and a large hematoma in the axilla and chest wall. The second, a 63-year-old man, had a pseudoaneurysm and palpable peripheral pulses. Both underwent urgent computed tomography, which confirmed the clinical diagnosis, and the patients were taken to the operating room. In the first patient, intraoperative angiogram through both the brachial and the femoral route showed complete disruption of the axillary artery rendering an endovascular approach not possible. Proximal balloon occlusion was then undertaken through the femoral artery, controlling the bleeding and allowing easier dissection of the ruptured segment. Revascularization was performed with an interposition polytetrafluoroethylene (PTFE) bypass restoring normal blood supply to the upper extremity. The second patient had a Viabhan (W.L. Gore, Flagstaff, Ariz) stent-graft implanted through the brachial artery with an excellent clinical and angiographic result. As expected, both patients had significant neurologic morbidity due to associated brachial plexus palsy. Ruptured axillary artery after shoulder dislocation is very uncommon. Endovascular repair and hybrid procedures combining open and endovascular techniques can offer reliable solutions to these challenging problems.

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Konstantinos O. Papazoglou

Aristotle University of Thessaloniki

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Thomas S. Gerassimidis

Aristotle University of Thessaloniki

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Ioakeim T. Giagtzidis

Aristotle University of Thessaloniki

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Dimitrios Karamanos

Aristotle University of Thessaloniki

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Thomas E. Kalogirou

Aristotle University of Thessaloniki

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D. Papadimitriou

Aristotle University of Thessaloniki

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Neophytos Zambas

Aristotle University of Thessaloniki

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Filippos P. Demiropoulos

Aristotle University of Thessaloniki

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Apostolos Kamparoudis

Aristotle University of Thessaloniki

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Ioannis Pliatsios

Aristotle University of Thessaloniki

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