Cengiz Köksal

Attenuation of Ischemia/Reperfusion Injury by N-Acetylcysteine in a Rat Hind Limb Model

BACKGROUND Ischemia/reperfusion is a complex set of events with severe pathologic consequences. Reperfusion initiates both the local and systemic damage in part through rapid oxygen generation. N-acetylcysteine (NAC) is a scavenger of free radical species, inhibits neutrophil accumulation, acts as a vasodilator and also improves microcirculation. In present study, we examined the protective effect of NAC in a rat hind limb ischemia/ reperfusion model. Dimethyl-sulfoxide (DMSO), a well-known antioxidant was also tested for comparison. MATERIALS AND METHODS Ischemia was induced for 4 h by vascular clamping and followed by 1 h of reperfusion. Muscle injury was evaluated in 3 groups as a saline group (control), DMSO group, and NAC group. Plasma levels of creatine kinase, lactate dehydrogenase, thiobarbituric acid reactive substances (TBARS), and blood HCO(3), as well as muscle tissue TBARS, were measured at the end of reperfusion. Muscle tissue samples were taken for histological evaluation. RESULTS DMSO and NAC group showed significant amelioration of plasma CPK (P < 0.05, P < 0.05), plasma TBARS (P < 0.05, P < 0.05), and muscle tissue TBARS (P < 0.05, P < 0.05) compared with the control group. Similarly, neutrophil infiltration in DMSO and NAC groups were significantly less prominent than the control group (P < 0.01, P < 0.01). CONCLUSIONS These results show that NAC improved effectively ischemia reperfusion injury in a rat hind limb model.

Surgical treatment of Buerger's disease.

We aimed to evaluate the characteristics of 198 new patients with Buergers disease treated surgically in the last decade. We also compared these results with our former series reported in 1993. The records of patients with Buergers disease who were enrolled in an ongoing investigational protocol between 1991 and 2001 were reviewed. Sympathectomy was carried out in 161 patients and revascularization in 19 patients. The cumulative secondary patency rate was 57.9% for bypass grafts at a mean follow-up of 5.4 years. Clinical outcome following sympathectomy was considered improved in 52.3% of patients, stable in 27.8%, and worse in 19.8%. Seven major and 36 minor amputations were performed, with a limb salvage rate of 95.6%. The aggressiveness of the disease has increased compared with previous series, parallel to the expansion of cigarette consumption. Bypass surgery should be considered for patients with severe ischemia who have target vessels. Sympathectomy still has a role to improve distal flow.

Abdominal aortic aneurysm or aortic occlusive disease: role of trace element imbalance.

The nature of the relationship between atheromatous disease and degenerative aneurysm is yet to be defined. The purpose of this study was to compare tissue Fe, Cu, Zn, and thiobarbituric acid reactive substances (TBARS) levels (as a marker of lipid peroxidation) in the abdominal aorta in relation to the development of aneurysmal and occlusive disease in the infrarenal aorta. This was a prospective clinical study in an institutional referral center, in hospitalized patients. Eighty male patients who underwent surgery for abdominal aortic aneurysm (AAA) or aortic occlusive disease (AOD) were included in the study. Age, risk factors and comorbid conditions were recorded, including diabetes mellitus, hypertension, coronary artery disease, smoking, and chronic obstructive pulmonary disease. Aortic wall biopsies were collected at operation from the anterolateral section of the infrarenal aorta. Tissue Fe, Cu, Zn, and TBARS levels were determined. The mean age of the AAA group was 66.2 (56—75) years and of the AOD group 57.8 (47—72) years (p <0.001). There was a higher prevalence of hypertension in AAA patients compared to AOD patients (62.5%, 35% respectively; p <0.05). The comparison of tissue Zn levels showed no significant difference. Tissue levels of Fe, Cu, and TBARS were found to be higher in the AAA group, compared with the AOD group (p<0.001 for each). These results suggest that higher oxidative stress as a result of higher Fe and Cu levels in the AAA, compared with AOD, may be one of the contributing factors in aneurysmal formation as a result of promoted wall erosion.

The effects of clopidogrel and calcium dobesilate on intimal hyperplasia following vascular injury.

Abstract Background: Neo-intimal hyperplasia is one of the most common causes of failure of arterial patency following cardiovascular interventions. It has been proposed that clopidogrel and calcium dobesilate may play an important role in the amelioration of intimal hyperplasia. The aim of this study is to examine the effect of these agents on inti-mal hyperplasia occurring after experimental balloon catheter injury. Material and Methods: Twenty-four male New Zealand rabbits were divided into three groups. Endothelial injury was caused by introducing a 2.5 χ 20 mm balloon angioplasty catheter into the left iliac artery. After the procedure, clopidogrel (25 mg/kg/day/orally) or calcium dobesilate (100 mg/kg/day/orally) were given for 2 weeks. Eight rabbits were given a placebo and served as controls. The contralateral non-injured iliac arteries of the control group were considered as normal iliac artery samples. Iliac artery specimens were examined planimetrically and the intima/media ratio was obtained for each vessel. Results: In the control group, the intima/media ratio was still significantly higher (p < 0.05) than the contralateral normal artery 14 days after the balloon catheter injury. In the clopidogrel and calcium dobesilate groups, this ratio had significantly decreased when compared with the control group (p < 0.05). No significant difference was found when the clopidogrel and calcium dobesilate groups were compared. Conclusion: The anti-agregant agent clopidogrel, and the venous endothelial regulator calcium dobesilate, ameliorate intimal hyperplasia after experimentally induced vascular injury in rabbit iliac arteries.

The Altered Hemorheologic Parameters in Thromboangiitis Obliterans: A New Insight

The hemorheologic abnormalities were studied in patients suffering from thromboangiitis obliterans (TAO) and compared findings with those of patients suffering from critical limb ischemia because of peripheral atherosclerotic obstructive disease (PAOD) and the healthy subjects. This prospective study included 20 patients with TAO, 20 patients with PAOD, and 20 healthy subjects. Hematocrit, plasma fibrinogen, red blood cell rigidity, and blood and plasma viscosity were determined in all groups. Hematocrit values of the TAO group were significantly higher than those of the PAOD group and the control group (p<0.001 and p<0.001, respectively). BV at a shear rate of 6.00 sec-1 was higher in TAO than the PAOD and control (p<0.01 and p<0.05, respectively). BV at a shear rate of 225 sec-1 was higher in the TAO and PAOD than the control (p<0.001 and p<0.001, respectively) and also PAOD values were higher than the TAO (p<0.05). RBC rigidity was higher in the TAO and PAOD than the control (p<0.001 and p<0.05, respectively) and these values were higher in PAOD than the TAO (p<0.05). These results show the impairment in hemorheologic parameters in TAO may provide a new insight into the treatment of patients with TAO in the active period of the disease.

The Role of Polytetrafluoroethylene Graft Material in Buerger's Disease

The early and long-term results of polytetrafluoroethylene (PTFE) grafts in different anatomical locations were evaluated in 14 patients with Buergers disease (thromboangiitis obliterans). During a 10-year period, 2160 patients with peripheral vascular disease were treated and, in 258, the diagnosis of Buergers disease was made. Fourteen of these 258 patients underwent revascularization with PTFE grafts. In a follow-up period, up to 8 years patency rates were as follows: aorto/ilofemoral bypass 80%, femoropopliteal bypass 40%, femorocrural bypass 50% with a cumulative patency rate of 57.1%, and limb salvage rate of 88.9%. Because of the diverse nature and small number of the operations, the numerical results are not amenable to statistical analysis, but 88.9% limb salvage rate is satisfying in Buergers disease. To the best of our knowledge, this is the first report on the use of PTFE grafts in Buergers disease and it validates limb salvage even below the inguinal ligament.

Intravenous iloprost for treatment of critical limb ischemia in patients unsuitable for revascularization

Introduction Whether medical therapy alone may reduce the amputation rates in patients with chronic limb ischemia and who are unsuitable for revascularization is a controversial topic. In this study, we aimed to investigate the effects of 1 week infusion of iloprost in the treatment of patients with chronic limb ischemia. Materials and methods Twenty-seven consecutive patients were included in the study. There were 23 men (85.2%) and 4 women (14.8%) with a mean age of 68.93 ± 14.84 years. Patients were considered eligible if they were unsuitable for surgical and endovascular revascularization. Follow-up was made on 10th day and 6th month and included ankle brachial index and clinical assessment. Results Minor side effects occurred in four patients (16.0%), but the treatment was continued. In-hospital mortality occurred in one patient (4.0%). Another two patients died and four patients received amputation until follow-up (overall mortality 11.1%). There was significant increase in mean ankle-brachial index values between 1st day and 10th day (p < 0.001), between 1st day and 6th month (p < 0.001), and between 10th day and 6th month (p < 0.001). Conclusion One-week treatment with iloprost may provide both long lasting symptomatic benefit and may improve hemodynamic parameters, which were shown to predict future amputation.

Quality of Life After Open Surgical

Objective This study aims to compare open surgical and endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms in terms of their effects on quality of life, using Short Form-36 (SF-36). Methods A total of 133 consecutive patients who underwent EVAR or open surgical repair for infra-renal abdominal aorta aneurysm between January 2009 and June 2014 were included in the study. Twenty-six (19.5%) patients died during follow-up and were excluded from the analysis. Overall, 107 patients, 39 (36.4%) in the open repair group, and 68 (63.6%) in the EVAR group, completed all follow-up visits and study assessments. Quality of life assessments using SF-36 were performed before surgery and at post-operative months 1, 6, and 12. Results The mean duration of follow-up was 29.55±19.95 months. At one month, both physical and mental domains of the quality of life assessments favored EVAR, while the two surgical approaches did not differ significantly at or after six months postoperatively. Conclusion Despite anatomical advantages and acceptable mid-phase mortality in patients with high- or medium-risk for open surgery, EVAR did not exhibit a quality of life superiority over open surgery in terms of physical function and patient comfort at or after postoperative six months.

Comparison of Early Outcomes with Three Approaches for Combined Coronary Revascularization and Carotid Endarterectomy

Objective This study aims to compare three different surgical approaches for combined coronary and carotid artery stenosis as a single stage procedure and to assess effect of operative strategy on mortality and neurological complications. Methods This retrospective study involves 136 patients who had synchronous coronary artery revascularization and carotid endarterectomy in our institution, between January 2002 and December 2012. Patients were divided into 3 groups according to the surgical technique used. Group I included 70 patients who had carotid endarterectomy, followed by coronary revascularization with on-pump technique, group II included 29 patients who had carotid endarterectomy, followed by coronary revascularization with off-pump technique, group III included 37 patients who had coronary revascularization with on-pump technique followed by carotid endarterectomy under aortic cross-clamp and systemic hypothermia (22-27ºC). Postoperative outcomes were evaluated. Results Overall early mortality and stroke rate was 5.1% for both. There were 3 (4.3%) deaths in group I, 2 (6.9%) deaths in group II and 2 (5.4%) deaths in group III. Stroke was observed in 5 (7.1%) patients in group I and 2 (6.9%) in group II. Stroke was not observed in group III. No statistically significant difference was observed for mortality and stroke rates among the groups. Conclusion We identified no significant difference in mortality or neurologic complications among three approaches for synchronous surgery for coronary and carotid disease. Therefore it is impossible to conclude that a single principle might be adapted into standard practice. Patient specific risk factors and clinical conditions might be important in determining the surgical tecnnique.