Christos Bakoyiannis
National and Kapodistrian University of Athens
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Featured researches published by Christos Bakoyiannis.
Surgery Today | 2005
Theodoros Diamantis; Christos Tsigris; Andreas Kiriakopoulos; Efstathios Papalambros; John Bramis; Panagiotis O. Michail; Evangelos Felekouras; John Griniatsos; Theofhilos Rosenberg; Nikolaos Kalahanis; Athanassios Giannopoulos; Christos Bakoyiannis; Elias Bastounis
PurposeBile duct injury (BDI) represents the most serious complication of laparoscopic cholecystectomy (LC). The aim of this retrospective single-institution study was to evaluate the real incidence of BDI during laparoscopic and open cholecystectomy (OC) in a tertiary academic center in Athens, Greece.MethodsBetween January 1991 and December 2001, 3 637 patients underwent cholecystectomy in our department; as LC in 2 079 patients (LC group) and as OC in 1 558 patients (OC group). All the LCs were performed or supervised by five staff surgeons and all the OCs were performed or supervised by another five staff surgeons.ResultsThere were 13 BDIs associated with LC (0.62%) and 6 associated with OC (0.38%) (P = 0.317). There was one death associated with BDI after LC. Only two (15.4%) of the BDIs associated with LC occurred within the proposed learning curve limit of 50 LCs per individual surgeon.ConclusionLaparoscopic cholecystectomy is safe and is not associated with a higher incidence of BDI than OC. Moreover, we did not find that the learning curve for LC affected BDI occurrence.
Angiology | 2007
Efstathios Papalambros; Fragiska Sigala; Sotiris Georgopoulos; Kosmas I. Paraskevas; Ioanna Andreadou; Xaralambos Menenakos; Panagiotis Sigalas; Alexandros Papalambros; G. Vourliotakis; Athanasios Giannopoulos; Christos Bakoyiannis; Elias Bastounis
Ischemia-reperfusion injury significantly contributes to abdominal aortic aneurysm (AAA)— related mortality and morbidity; therefore, we measured oxidative stress during open AAA repair and investigated any potential associations with intraoperative or perioperative events (aortic clamping time, blood loss, and the need to transfer to the intensive care unit). Blood samples were collected at specific time points from 53 patients undergoing open AAA repair: (1) before induction of anesthesia; (2) 15, 30, 60, and 120 minutes after aortic clamping; (3) 15 and 60 minutes after clamp removal; and (4) 24 hours postoperatively. Malondialdehyde (MDA) levels were measured by a spectrophotometric method. Baseline MDA values in patients with AAA were significantly higher than in controls (P < .0001). A positive correlation was found between preoperative MDA levels and the size of AAAs (Pearson correlation = 0.578, P < .001). No difference was observed in MDA levels between ruptured and nonruptured AAAs; however, when all symptomatic patients (ruptured and elective symptomatic AAAs, n = 18) were considered, there was a significant elevation in MDA levels (P < .001). There was also a significant increase in MDA values in patients transferred postoperatively to the intensive care unit (P < .001). Finally, a positive association was found between the duration of aortic clamping with MDA values at 15 and 60 minutes after declamping, but not after 24 hours (Pearson correlation = 0.467, P < .001). MDA levels may predict the postoperative course of elective and ruptured AAAs.
Annals of Vascular Surgery | 2013
George Galyfos; Fragiska Sigala; Konstantinos Tsioufis; Christos Bakoyiannis; Emmanuel Lagoudiannakis; Andreas Manouras; George C. Zografos; Konstantinos Filis
BACKGROUND We conducted a comparison of postoperative cardiac damage, defined as cardiac troponin I (cTn-I) elevation, after carotid endarterectomy in low- and high-risk patients. METHODS The Stenting and Angioplasty with Protection in Patients at High Risk for Endarterectomy (SAPPHIRE) criteria for stratifying patients considered for carotid endarterectomy into low and high surgical risk groups were used prospectively. All patients had preoperative full cardiologic evaluations and cTn-I value assessments that were repeated on postoperative days 1, 3, and 7. Postoperative cTn-I values ranging from 0.05 to 0.5 ng/mL were classified as myocardial ischemia; values >0.5 ng/mL were classified as myocardial infarction. RESULTS Mortality was 1.2%, the stroke rate was null, and symptomatic myocardial infarction was null. Among the 56 high-risk patients, 8 had cTn-I values>0.5 ng/mL. Among the 106 low-risk patients, 10 patients had cTn-I value >0.5 ng/mL and 4 patients had cTn-I values that were >0.05 ng/mL and ≤0.5 ng/mL. All patients with increased cTn-I levels were asymptomatic. Concerning all patients, the mean preoperative cTn-I value was 0.007 ng/mL, which increased to 0.438 ng/mL on postoperative day 1 (P=0.017), 0.168 ng/mL on postoperative day 3 (P=0.06), and 0.019 ng/mL on postoperative day 7 (P=0.02). In the high-risk group, the mean preoperative cTn-I value was 0.008 ng/mL, which increased to 0.829 ng/mL on postoperative day 1, 0.270 ng/mL on postoperative day 3, and 0.030 ng/mL on postoperative day 7. In the low-risk group, the mean preoperative cTn-I value was 0.007 ng/mL, which increased to 0.198 ng/mL on postoperative day 1, 0.119 ng/mL on postoperative day 3, and 0.013 ng/mL on postoperative day 7. Patients without cardiac damage showed analogous tendencies in their troponin values. Comparison of troponin values between high- and low-risk patients on each day showed no statistical difference. Electrocardiogram alterations were seen in 20 of the 22 patients with asymptomatic troponin elevation but in none without troponin elevation. CONCLUSIONS Carotid endarterectomy is followed by an increase in cTn-I value>0.5 ng/mL in 14% of all cases, although symptomatic cardiac ischemia is very low. However, high-risk patients as defined by the SAPPHIRE criteria do not show an increased risk of cardiac damage compared to low-risk patients. Larger studies using cTn-I as a marker of postoperative cardiac damage, after carotid endarterectomy or stenting, are needed.
Cerebrovascular Diseases | 2011
Athanasios Katsargyris; Sotirios Tsiodras; Stamatios Theocharis; Konstantinos Giaginis; Ioanna Vasileiou; Christos Bakoyiannis; Sotiris Georgopoulos; Elias Bastounis; Chris Klonaris
Background: A growing body of evidence supports a role for Toll-like receptor 4 (TLR4), a primary receptor of the innate immune system, in atherosclerosis initiation and progression. Carotid atheroma macrophages (MACs) and smooth muscle cells (SMCs) express TLR4; nevertheless, correlations with epidemiological and clinical variables and especially cerebrovascular symptomatology remain unsettled. Methods: Carotid atherosclerotic plaques were obtained by standard carotid endarterectomy on 157 patients with carotid artery disease (84 asymptomatic – 73 symptomatic). TLR4 expression in MACs and SMCs of carotid atheroma was detected by immunohistochemistry techniques. TLR4 positivity, overexpression and intensity of immunostaining in MACs and SMCs were correlated with cerebrovascular symptomatology, epidemiological and clinical variables. Results: MAC TLR4 positivity was noted in 129 (82.2%) patients. Patients receiving statins had significantly lower TLR4 expression. Rates of MAC TLR4 positivity were higher among symptomatic patients (odds ratio, OR = 5.1; 95% confidence interval, CI = 1.8–14.3; p < 0.001); the association was stronger for transient ischemic attacks. TLR4 overexpression was also significantly enhanced among symptomatic patients (OR = 2.3; 95% CI = 1.02–5.03; p < 0.05). No correlations were detected between SMC TLR4 expression and cerebrovascular symptoms. In multivariate models adjusting for age, gender, body mass index, hyperlipidemia and smoking, MAC TLR4 positivity was associated with a cerebrovascular event during the last 6 months (OR = 4; 95% CI = 1.2–13.3; p = 0.02). Conclusions: Symptomatic carotid artery plaques are characterized by increased expression of TLR4 in macrophages supporting a potential role for TLR4 in the pathophysiology and clinical presentation of cerebrovascular disease. Further investigation is warranted.
Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2006
Ioannis Papaconstantinou; Michael Kontos; Evangelos Prassas; John Karavokyros; Christos Bakoyiannis; Emmanouil Pikoulis; Michael Safioleas; Athanasios Giannopoulos; Elias Bastounis; Evangelos Felekouras
The aim of this study is to describe an alternative technique, using radio frequency energy to perform pericystectomy for hepatic echinococcosis. We present 3 patients with hepatic echinococcosis who were treated with radio frequency ablation (RFA)-assisted pericystectomy. A Radionics Cooltip Radio Frequency System (Tyco, Greece, Radionics) with a single shaft 15 cm long needle electrode and a 2 cm exposure tip, was used. The needle electrode was inserted in consecutive sites into the “healthy” hepatic parenchyma close to the cyst wall, so that a tissue zone around the cystic cavity was gradually ablated. The complete ablation of a site was followed by sharp division of the parenchyma. The operation completed successfully in all patients. Minor bleeding and/or bile leakage were successfully controlled with RFA coagulation. No other hemostatic method was used. The postoperative course was uneventful. No evidence of recurrent disease, or any other cause of morbidity, has been demonstrated at follow up (2 y). RFA-assisted pericystectomy for hepatic hydatid disease in experienced hands, might be useful to perform a “sterile” resection, eradicating single or multiple cysts and preventing local recurrence, with minimal morbidity.
Frontiers in Surgery | 2017
Konstantinos Filis; George Galyfos; Fragiska Sigala; Konstantinos Tsioufis; Ioannis Tsagos; Georgios Karantzikos; Christos Bakoyiannis; George C. Zografos
Several risk factors including short or highly angulated proximal aortic neck have been associated with long-term outcomes after endovascular or open abdominal aortic aneurysm (AAA) repair. However, research data have emerged recently concerning the behavior of proximal aortic neck, and several authors have tried to evaluate this behavior after endovascular or open repair. Additionally, computed tomography angiography (CTA) remains the golden standard for detecting and observing the morphology of an AAA, both before and after treatment. Moreover, the question of whether the proximal neck’s progression independently affects postoperative morbidity and reintervention risks still remains. Therefore, this focused review aims to present all relevant data on the behavior of an AAAs neck, based on CTA imaging before and after repair, in order to produce useful conclusions for future clinical practice.
Case reports in vascular medicine | 2012
Christos Bakoyiannis; Ioannis P Anastasiou; Andreas Koutsoumpelis; Evangelos Fragiadis; Eleni Felesaki; Marina Kafeza; Sotirios E Georgopoulos; Christos Tsigris
The use of shockwave lithotripsy is currently the mainstay of treatment in renal calculosis. Several complications including vessel injuries have been implied to extracorporeal shockwave lithotripsy. We report an isolated dissection of the superior mesenteric artery in a 60-year-old male presenting with abdominal pain which occurred three days after extracorporeal shockwave lithotripsy. The patient was treated conservatively and the abdominal pain subsided 24 hours later. The patients history, the course of his disease, and the timing may suggest a correlation between the dissection and the ESWL.
Acta Chirurgica Belgica | 2006
Christos Bakoyiannis; G. Vourliotakis; S. H. Georgopoulos; Christos Klonaris; Ioanna Skrapari; E. L. Felekouras; Elias Bastounis
Abstract Objective : Abdominal aortic aneurysm (AAA) in patients with end stage renal disease (ESRD) represents a challenging therapeutic problem. This study was undertaken to analyze the surgical outcome of AAA repair in patients with ESRD and discuss the optimal peri-operative management of problems that resulted. Methods : Between January 1995 and January 2005, 11 patients with ESRD underwent abdominal aortic aneurysm repair. All patients were under chronic haemodialysis. Risk factors related to surgical morbidity were evaluated. Results : The average age was 68 years (57–84 years). Nine patients were men: 8 were hypertensive, 6 had diabetes, 4 had coronary artery disease, 3 had suffered a previous stroke, 3 had prior myocardial infarct and 8 were smokers. The duration of haemodialysis was 19 months (range 2 to 46 months). Five of the 11 patients had bilateral common iliac aneurysms in addition to the abdominal aortic aneurysm. The average diameter of infrarenal AAA was 6 cm (4.8–7.5). The mean duration of operation was 191 min. All patients underwent haemodialysis on the day before operation with an average period of 8.5 hours (6–12) and 2 to 20 hours postoperatively. The mean follow-up was 11.5 months (range 1 to 93 months). None of the patients died during the 30-day postoperative period. Two patients died from heart failure 3 and 7 months later. Conclusion : Abdominal aortic aneurysm can be repaired in patients with end stage renal disease with good results, despite the increased morbidity and mortality of this population.
Acta Chirurgica Belgica | 2006
Christos Bakoyiannis; Sotiris Georgopoulos; Nikolaos Tsekouras; Christos Klonaris; Ioanna Skrapari; Emmanouil Pikoulis; Evangelos Felekouras; A. Leppaniemi; Elias Bastounis
Abstract Introduction: The purpose of this study is to present our experience in the management of patients with abdominal aortic aneurysms (AaA) and aneurysms in both the internal iliac arteries (IIA) at the same time. Methods: Between 2000 and 2005, a series of 13 patients with AAA and also aneurysms in both the IIA, were treated in our clinic. They were all men with a mean age of 74 years. The size of the IIA aneurysms (IIAA) ranged from 2.0 to 8.0 cm (mean, 3.4 cm). All patients underwent an aneurysmatectomy of the AAA and placement of a prosthetic bifurcated aorto-biiliac or-bifemoral bypass, by a transperitoneal approach. The management of one of the two IIAA was the aneurysmatectomy and the direct revascularization of the healthy peripheral portion of the remaining IIA with the ipsilateral leg of the aorto-biiliac bypass. The other IIAA was treated with proximal ligation of its neck and aneurys-morraphy. Results: No patient died during the first 30 postoperative days. Morbidity was about 7.7% (one patient suffered from ‘trash foot’, which was treated successfully with conservative measures). Finally, the mean stay in hospital was 7 days and no patient clinically presented symptoms of pelvic or colonic ischaemia. Conclusions: Simultaneous treatment of AAA and bilateral IIA aneurysms is a technically difficult, but safe procedure, if it is performed meticulously. Revascularization of at least one internal iliac artery is strongly recommended in order to avoid dangerous complications, such as pelvic or colonic ischaemia.
European Journal of Vascular and Endovascular Surgery | 2007
Elias Bastounis; Christos Bakoyiannis; C. Cagiannos; Christos Klonaris; C. Filis; E.E. Bastouni; Sotiris Georgopoulos