Athanasios D. Giannoukas
RMIT University
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Journal of Vascular Surgery | 1994
Nicos Labropoulos; Miguel Leon; Andrew N. Nicolaides; Athanasios D. Giannoukas; N. Volteas; Philip Chan
PURPOSE The aim of this study was to assess the distribution and extent of valvular incompetence in patients with reflux confined to the superficial venous system and correlate the extent of such reflux with clinical symptoms and signs. METHODS Two hundred fifty-five limbs of 217 patients with superficial venous insufficiency and normal perforating and deep veins were examined with color-flow duplex imaging. One hundred twenty-three limbs (48.2%) of 102 patients had reflux confined to the long saphenous system, 83 limbs (32.6%) of 72 patients had reflux confined to the the short saphenous system, and 49 limbs (19.2%) of 43 patients had reflux in both long and short saphenous systems. RESULTS In the long saphenous system the commonest pattern of reflux was that which extended throughout the length of long saphenous vein (LSV) (47%). Ache, swelling, and skin changes were common in the presence of below knee reflux irrespective whether the thigh segment was involved. Ulceration (8%) was found only in limbs with reflux extending throughout the length of LSV. In the short saphenous system the most common pattern of reflux extended throughout the length of short saphenous vein (SSV) (57%) without involvement of Giacomini or gastrocnemial veins. Ache and swelling were present in 62% and 72% of the limbs, but this incidence was not related to the extent of reflux. Swelling, skin changes, and ulceration occurred only when the whole of the SSV was involved. In the limbs with reflux in both the long and short saphenous systems, the most common pattern of reflux extended throughout the length of both systems (45%). In these limbs the incidence of swelling was 80%. The incidence of skin changes went from 44% when the below-knee segment of the LSV was involved to 73% when reflux occurred throughout the LSV and SSV. Ulceration (14%) was found only in the latter situation. Variable patterns of saphenogastrocnemial termination were seen. In 57.8% of the limbs SSV joined the popliteal vein just above the popliteal crease, whereas the SSV terminated in the thigh in 26.6%. CONCLUSIONS We conclude that ache, ankle edema, and skin changes in limbs with reflux confined to the superficial venous system are predominantly associated with reflux in the below-knee veins. Ulceration is found only when the whole of the LSV is involved (8%) or when reflux is extensive in both LSV and SSV (14%).
Journal of Vascular Surgery | 1997
Nicos Labropoulos; Athanasios D. Giannoukas; Kostas Delis; M. Ashraf Mansour; Steven S. Kang; Andrew N. Nicolaides; John S.P. Lumley; William H. Baker
PURPOSE This study was designed to identify the origin of lower limb primary venous reflux in asymptomatic young individuals and to compare patterns of reflux with age-matched subjects with prominent or clinically apparent varicose veins. METHODS Forty age- and sex-matched subjects with no symptoms (age, 15 to 35 years; 80 limbs; group A), 20 subjects (age, 19 to 32 years; 40 limbs) with prominent but nonvaricose veins (n = 26 limbs; group B), and 50 patients (age, 17 to 34 years; 100 limbs) with varicose veins (n = 64; group C) were examined with color flow duplex imaging. All proximal veins (above popliteal skin crease), superficial, perforator, and deep, in the lower limb were examined in the standing position, and all the distal veins in the sitting position. Patients who had a documented episode of superficial or deep vein thrombosis, previous venous surgery, or injection sclerotherapy were excluded from the study. RESULTS The prevalence of reflux in group A was 14% (11 of 80), in group B 77% (31 of 40), and in group C 87% (87 of 100). In more than 80% of limbs in the three groups, reflux was confined to the superficial veins alone. Deep venous reflux or combined patterns of reflux were uncommon even in group C. Reflux was detected in all segments of the saphenous veins and their tributaries. In the 125 limbs that had superficial venous incompetence, the below-knee segment of the greater saphenous vein was the most common site of reflux (85, 68%), followed by the above-knee segment of greater saphenous vein (69, 55%) and the saphenofemoral junction (41, 32%). Nonsaphenous reflux was rare (3, 2.4%). Reflux in the lesser saphenous vein (21, 17%) was seen in all groups, whereas involvement of both greater and lesser saphenous veins (8, 6.4%) was seen in group C alone. The incidence of multisegmental reflux was significantly higher in group C (61 of 64, 95%) than in group A (two of 11, 18%) or group B (14 of 26, 54%). The prevalence of distal reflux was comparable in all groups. CONCLUSIONS Primary venous reflux can occur in any superficial or deep vein of the lower limbs. The below-knee veins are often involved in asymptomatic individuals and in those who have prominent or varicose veins. These data suggest that reflux appears to be a local or multifocal process in addition to or separate from a retrograde process.
Journal of Vascular Surgery | 2009
G.A. Antoniou; Stylianos Koutsias; Stavros A. Antoniou; Andreas Georgiakakis; Miltos K. Lazarides; Athanasios D. Giannoukas
BACKGROUND Aortoenteric fistula (AEF) is a critical clinical condition, which may present with gastrointestinal hemorrhage, with or without signs of sepsis. Conventional open surgical repair is associated with high morbidity and mortality. Endovascular stent graft repair has been attempted, but recurrent infection remains of major concern. We conducted a systematic review to assess potential factors associated with poor outcome after endovascular treatment. METHODS The English literature was searched using the MEDLINE electronic database up to April 2008. All studies reporting on the primary management of primary or secondary AEF with endovascular stent graft repair were considered. RESULTS Data were extracted from 33 reports that included 41 patients and were entered in the final analysis. Persistent/recurrent/new infection or recurrent hemorrhage developed in 44% of the patients, after a mean follow-up period of 13 months (range, 0.13-36). Secondary, as compared to primary, AEF had an almost threefold increased risk of persistent/recurrent infection. Evidence of sepsis preoperatively was found to be a factor indicating unfavorable outcome (P < .05). Persistent/recurrent/new infection after treatment was associated with worse 30-day and overall survival compared with those who did not develop sepsis (P < .05). CONCLUSION Endovascular stent graft repair of AEF was associated with a high incidence of infection or recurrent bleeding postoperatively. Evidence of sepsis preoperatively was indicating poor outcome.
European Journal of Vascular and Endovascular Surgery | 2009
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 | 1995
Nicos Labropoulos; Athanasios D. Giannoukas; Andrew N. Nicolaides; Ganesh Ramaswami; Miguel Leon; Paul E. Burke
PURPOSE This study was conducted to investigate the distribution of reflux in the veins adjacent to or within the venous ulcer (local) and to correlate it with the pattern of disease of the axial veins (all veins away from the ulcer area) of the affected limb. METHODS Forty-three ulcers in 34 legs of 33 patients were examined with color-flow duplex imaging. The veins in the area of the ulcer were scanned with a sterile technique. RESULTS In 17 legs (50%) there was documented past deep venous thrombosis. All of the 34 limbs had reflux in the superficial or deep axial veins either alone or in combination. Fifteen of these limbs (44%) also had perforating vein incompetence, but none had perforator incompetence alone. Six ulcers showed no evidence of reflux in the local veins when scanned through the ulcer bed despite the presence of reflux in the axial veins of the limb. In 13 limbs with 17 ulcers, either the superficial axial veins alone or the deep axial veins alone were affected (with or without associated perforator incompetence). Examination of the local veins associated with these 17 ulcers revealed a similar pattern of reflux to that seen in the axial veins in 13 cases, with the remaining 4 ulcers showing no local venous abnormality. The pattern of reflux was less predictable at the local ulcer level in limbs where both superficial and deep venous incompetence coexisted in the axial veins. Only 7 of the 26 ulcers (27%) in these limbs had similar evidence of combined superficial and deep reflux in the local ulcer veins, whereas 10 ulcers (39%) were associated with local reflux in the superficial or deep veins alone. CONCLUSIONS These data show that 86% (37/43) of the ulcers has some degree of reflux in the local area, the pattern of which may differ from the axial vein disease. Treatment of the local hemodynamic abnormalities may be an important factor in the healing of the ulcers and in the prevention of their recurrence.
Journal of Vascular Surgery | 2012
George S. Sfyroeras; Nikolaos Roussas; Vassileios Saleptsis; Christos Argyriou; Athanasios D. Giannoukas
OBJECTIVE Periodontitis is a very common human infection. There is evidence that periodontitis is associated with cerebrovascular disease (CVD) and stroke. The aim of this study is to examine the relationship between periodontal disease and CVD in observational studies. METHODS An electronic search of the English literature using PubMed was conducted. A meta-analysis of the studies reporting on the risk of stroke in patients with periodontitis was performed. RESULTS Six prospective and seven retrospective studies met the inclusion criteria. Patients with both hemorrhagic and ischemic cerebrovascular events, fatal and nonfatal, were included. Definition of periodontitis was taken directly from included studies. Most studies have been adjusted for common cardiovascular risk factors. Separate statistical analysis was performed for prospective and retrospective studies. Overall adjusted risk of stroke in subjects with periodontitis was 1.47 times higher than in subjects without (95% confidence interval, 1.13-1.92;P = .0035) in prospective and 2.63 times (95% confidence interval, 1.59-4.33;P = .0002) in retrospective studies. The application of the trim and fill algorithm does not change the initial significant inference. CONCLUSIONS There is evidence that periodontitis is associated with increased risk of stroke. However, the results of this meta-analysis should be interpreted with caution because of the heterogeneity of the studies as well as the differences in periodontitis definition.
Microvascular Research | 2010
Aristotle G. Koutsiaris; Sophia V. Tachmitzi; Periklis Papavasileiou; Nick Batis; Maria G. Kotoula; Athanasios D. Giannoukas; Tsironi E
Axial red blood cell velocity pulse was quantified throughout its period by high speed video microcinematography in the human eye. In 30 conjunctival precapillary arterioles (6 to 12 microm in diameter) from 15 healthy humans, axial velocities ranged from 0.4 (the minimum of all the end diastolic values) to 5.84 mm/s (the maximum of all the peak systolic values). With the velocity pulse properly quantified, two parameters can be estimated: (1) the average velocity of the pulse during a cardiac cycle AVV (average velocity value) and (2) the magnitude of the pulsation using Pourcelots resistive index RI. These parameters are important for the estimation of other hemodynamic parameters such as the average volume flow and the average shear stress. The results of this study revealed that the AVV in the human precapillary arterioles ranged between 0.52 and 3.26 mm/s with a mean value for all microvessels of 1.66 mm/s+/-0.11(SE). The RI ranged between 35.5% and 81.8% with a mean value of 53.1%+/-2.2. Quantitative information was obtained for the first time on the velocity pulse characteristics just before the human capillary bed.
Journal of Endovascular Therapy | 2009
G.A. Antoniou; Stylianos Koutsias; Christos Karathanos; Giorgos S. Sfyroeras; Georgios Vretzakis; Athanasios D. Giannoukas
Purpose: To evaluate the outcomes of endovascular stent-graft repair of major abdominal arteriovenous fistulas. Methods: The English literature was systematically searched using the MEDLINE electronic database up to January 2009. All reports on endovascular stent-graft repair of major abdominal arteriovenous fistula were considered. Our experience of abdominal arteriovenous fistula was involved in the data analysis. The primary outcome measures were technical success and perioperative, 30-day, and overall mortality. Results: Data for the final analysis were extracted from 21 papers reporting on 22 patients and from the medical records of a patient treated at our institution. The most common causal associations of these fistulae were the presence of an aortoiliac aneurysm and previous endovascular aneurysm repair, accounting for 56% and 13% of all associations, respectively. The technical success rate was 96% (22/23). No perioperative or 30-day mortality was noticed during a mean follow-up of 9 months. The most common procedure-related complication was type II endoleak, which was found in 22% (5/23) of the patients. This event was either self limiting or required minimal percutaneous intervention. Conclusion: Endovascular stent-graft repair of major abdominal arteriovenous fistula is a safe and effective treatment option, with good short- and midterm results. However, no long-term data exist, and larger series are required to draw solid conclusions regarding the outcomes of this method.
Journal of Cardiothoracic Surgery | 2010
George Vretzakis; Athina Kleitsaki; Konstantinos Stamoulis; Metaxia Bareka; Stavroula Georgopoulou; Menelaos Karanikolas; Athanasios D. Giannoukas
BackgroundCardiac surgery is a major consumer of blood products, and hemodilution increases transfusion requirements during cardiac surgery under CPB. As intraoperative parenteral fluids contribute to hemodilution, we evaluated the hypothesis that intraoperative fluid restriction reduces packed red-cell (PRC) use, especially in transfusion-prone adults undergoing elective cardiac surgery.Methods192 patients were randomly assigned to restrictive (group A, 100 pts), or liberal (group B, 92 pts) intraoperative intravenous fluid administration. All operations were conducted by the same team (same surgeon and perfusionist). After anesthesia induction, intravenous fluids were turned off in Group A (fluid restriction) patients, who only received fluids if directed by protocol. In contrast, intravenous fluid administration was unrestricted in group B. Transfusion decisions were made by the attending anesthesiologist, based on identical transfusion guidelines for both groups.Results137 of 192 patients received 289 PRC units in total. Age, sex, weight, height, BMI, BSA, LVEF, CPB duration and surgery duration did not differ between groups. Fluid balance was less positive in Group A. Fewer group A patients (62/100) required transfusion compared to group B (75/92, p < 0.04). Group A patients received fewer PRC units (113) compared to group B (176; p < 0.0001). Intraoperatively, the number of transfused units and transfused patients was lower in group A (31 u in 19 pts vs. 111 u in 62 pts; p < 0.001). Transfusions in ICU did not differ significantly between groups. Transfused patients had higher age, lower weight, height, BSA and preoperative hematocrit, but no difference in BMI or discharge hematocrit. Group B (p < 0.005) and female gender (p < 0.001) were associated with higher transfusion probability. Logistic regression identified group and preoperative hematocrit as significant predictors of transfusion.ConclusionsOur data suggest that fluid restriction reduces intraoperative PRC transfusions without significantly increasing postoperative transfusions in cardiac surgery; this effect is more pronounced in transfusion-prone patients.Trial registrationNCT00600704, at the United States National Institutes of Health.
Angiology | 2010
Kosmas I. Paraskevas; Ioannis Kotsikoris; Sotirios A. Koupidis; Athanasios D. Giannoukas; Dimitri P. Mikhailidis
Signorelli et al in this issue of Angiology screened almost 3500 asymptomatic individuals (mean age 61.3 + 9.7 years) using the ankle brachial index (ABI) to detect unrecognized peripheral arterial disease (PAD). An ABI 0.9 was considered diagnostic. A total of 80 (2.3%) participants had unrecognized PAD. Of interest, among those individuals with unrecognized PAD, 5% (n 1⁄4 4) also had >75% asymptomatic carotid artery stenosis, whereas 12.5% (n 1⁄4 8) had an ejection fraction 30% asymptomatic carotid artery stenosis. In multivariate analysis, an ABI 50% stenosis, whereas 2.7% had an occluded internal carotid artery. An ABI 3-fold increased risk for >50% carotid stenosis compared with individuals with an ABI >0.9 (odds ratio [OR], 3.37; 95% CI, 1.04-10.93; P 1⁄4 .033). An ABI <0.9 in patients with asymptomatic PAD is not only a marker of generalized atherosclerosis but also a predictor of perioperative myocardial damage, should these patients undergo vascular surgery for an unrelated condition. The ABI was recorded in 627 consecutive patients undergoing carotid endarterectomy or abdominal aortic aneurysm repair. In multivariate analysis, an asymptomatic ABI <0.9 was associated with a 2.4-fold increased risk of perioperative myocardial damage (OR, 2.4; 95% CI, 1.4-4.2). Besides the ABI, several other markers/tests may reflect the presence of PAD. Examples include C-reactive protein (CRP) and functional photoplethysmograph technology using a noninvasive automated device. Both have the advantage that, unlike the ABI, they are less operator-dependent. Future studies should evaluate the prognostic significance of these variables in patients with PAD as well as their ability to identify unrecognized PAD. The identification of subclinical PAD holds implications for the timely initiation of preventive measures, namely smoking cessation, weight reduction, adoption of exercise, blood pressure and diabetes mellitus control, management of dyslipidemia, and antiplatelet treatment. Patients with PAD need to be closely monitored. The early diagnosis of PAD and the initiation of conservative measures is associated not only with a reduction in disease progression but also with several additional beneficial actions. For example, PAD is associated with the metabolic syndrome which requires treatment in its own right. Besides the management of dyslipidemia, routine statin treatment in patients with PAD is associated with an improvement in claudication, increased walking distance, and