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Öğe Decreased platelet activation and endothelial dysfunction after percutaneous mitral balloon valvuloplasty(Elsevier Ireland Ltd, 2003) Yetkin, E; Erbay, AR; Turhan, H; Ileri, M; Ayaz, S; Atak, R; Senen, KObjective: This study was conducted to assess the changes in platelet activation and endothelial dysfunction in patients with mitral stenosis (MS) and sinus rhythm (SR) following percutaneous mitral balloon valvuloplasty (PMBV). Background: Systemic thromboembolism is a serious complication in patients with valvular heart disease, and its incidence is highest in those with mitral stenosis. A hypercoagulable state has also been reported in patients with mitral stenosis and sinus rhythm. A recent study has shown that patients with previous PMBV had a lower incidence of thromboembolism. Methods and results: The study was conducted in 21 patients (two men, 19 women, mean age=34+/-6 years) with mitral stenosis and sinus rhythm (SR) who underwent percutaneous mitral balloon valvuloplasty and 17 healthy control subjects (two men, 15 women, mean age=33+/-6 years). Biochemical markers of platelet activity (beta thromboglobulin, BTG, and soluble P-selectin, sPsel) and endothelial dysfunction (von Willebrand Factor, vWF) were measured in both control subjects' and patients' serum samples taken immediately before PMBV and 24 h after PMBV procedure. All patients underwent successful PMBV Significant improvement of mitral valve area, pulmonary artery pressure, mean mitral gradients, and left atrial diameter were achieved in all patients after PMBV Compared with control subjects, patients with MS had higher plasma levels of BTG (66+/-26 ng/ml vs. 14+/-6 ng/ml, P<0.001), vWF (177+/-67 units/dl vs. 99+/-37 units/dl, P<0.0001), sPsel (226+/-74 ng/ml vs. 155+/-66 ng/ml, P<0.001). There was a significant reduction of plasma levels of BTG (66 +/- 26 ng/ml vs. 48 +/- 20 ng/ml, P=0.002), vWF (177 +/- 67 units/dl vs. 134 +/- 60 units/dl, P=0.001) and P-selectin (226 +/- 74 ng/ml vs. 173 +/- 71 ng/ml, P=0.008,) 24 h after PMBV Conclusion: We have shown that patients with severe MS and SR have increased platelet activation and endothelial dysfunction compared with control subjects and PMBV results in decreased platelet activity and improvement of endothelial injury. (c) 2003 Elsevier Ireland Ltd. All rights reserved.Öğe Elevated level of plasma homocysteine in patients with slow coronary flow(Elsevier Ireland Ltd, 2005) Erbay, AR; Turhan, H; Yasar, AS; Ayaz, S; Sahin, O; Senen, K; Sasmaz, HBack-ground: Elevated plasma levels of homocysteine are currently considered a major, independent risk factor for cardiovascular diseases. Recently, several investigators have Suggested that even mild elevation in plasma homocysteine level can severely disturb vascular endothelial function and subsequently impair coronary blood flow. Accordingly, we investigated plasma homocysteine level in patients with slow coronary flow. Method: Study population included 53 patients with angiographically proven normal coronary arteries and slow coronary flow in all three coronary vessels (group I, 21 females, 32 males, mean age=48 +/- 9 years), and 50 subjects with angiographically proven normal coronary arteries without associated slow coronary flow (group II, 22 females, 28 males, mean age=50 +/- 8 years). Coronary flow rates of all patients and control subjects were documented by Thrombolysis In Myocardial Infarction frame count (TIMI frame count). All patients in group I had TIMI frame counts greater than two standard deviations above those of control subjects (group II) and, therefore, were accepted as exhibiting slow coronary flow. The mean TIMI frame Count for each patient and control subject was calculated by adding the TIMI frame counts for each major epicardial coronary artery and then dividing the obtained value into 3. Plasma homocysteine level was measured in all patients and control subjects using commercially available homocysteine kits. Results: There was no statistically significant difference between two groups in respect to age, gender, hypertension, diabetes mellitus, hyperlipidemia and cigarette smoking (p > 0.05). Plasma homocysteine level of patients with slow coronary flow were found to be significantly higher than those of control subjects (15.5 +/- 5.7 vs. 8.7 +/- 4.2 mu M/l, respectively, p < 0.001). Moreover, we found a significant positive correlation between plasma homocysteine level and mean TIMI frame count (r=0.660, p < 0.001). Conclusion: We have shown that patients with slow coronary flow have raised level of plasma homocysteme compared to control subjects with normal coronary flow. This data suggests that elevated level of plasma homocysteine may play a role in the pathogenesis of slow coronary flow. (c) 2004 Elsevier Ireland Ltd. All rights reserved.Öğe Increased plasma soluble adhesion molecules; ICAM-1, VCAM-1, and E-selectin levels in patients with slow coronary flow(Elsevier Ireland Ltd, 2006) Turhan, H; Saydam, GS; Erbay, AR; Ayaz, S; Yasar, AS; Aksoy, Y; Basar, NBackground: Inflammation has been reported to be a major contributing factor to many cardiovascular events. In the present study, we aimed to evaluate plasma soluble adhesion molecules; intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and E-selectin as possible indicators of endothelial activation or inflammation in patients with slow coronary flow. Method: Study population included 17 patients with angiographically proven normal coronary arteries and slow coronary flow in all three coronary vessels (group I, 11 male, 6 female, mean age=48 +/- 9 years), and 20 subjects with angiographically proven normal coronary arteries without associated slow coronary flow (group II, 11 male, 9 female, mean age=50 +/- 8 years). Coronary flow rates of all patients and control subjects were documented by Thrombolysis In Myocardial Infarction frame count (TIMI frame count). All patients in group I had TIMI frame counts greater than two standard deviation above those of control subjects (group 11) and, therefore, were accepted as exhibiting slow coronary flow. Serum levels of ICAM-1, VCAM-1, and E-selectin were measured in all patients and control subjects using commercially available ELISA kits. Results: Serum ICAM-1, VCAM-1, and E-selectin levels of patients with slow coronary flow were found to be significantly higher than those of control subjects with normal coronary flow (ICAM-1: 545 +/- 198 ng/ml vs. 242 +/- 113 ng/ml respectively, p < 0.001, VCAM-1: 2040 +/- 634 ng/ml vs. 918 +/- 336 ng/ml respectively, p < 0.001, E-selectin: 67 +/- 9 ng/ml vs. 52 +/- 8 ng/ml respectively, p < 0.001). Average TIMI frame count was detected to be significantly correlated with plasma soluble ICAM-1 (r=0.550, p < 0.001), VCAM-1 (r=0.569, p < 0.001) and E-selectin (r = 0.443, p = 0.006). Conclusion: Increased levels of soluble adhesion molecules in patients with slow coronary flow may be an indicator of endothelial activation and inflammation and are likely to be in the causal pathway leading to slow coronary flow. (c) 2005 Elsevier Ireland Ltd. All rights reserved.Öğe Increased systemic and regional coagulation activity in patients with mitral stenosis and sinus rhythm(Westminster Publ Inc, 2003) Atak, R; Yetkin, E; Yetkin, O; Ayaz, S; Ileri, M; Senen, K; Turhan, HA hypercoagulable state has been reported in patients with mitral stenosis (MS) and sinus rhythm (SR). However it has been suggested that the coagulation activity may be increased only within the left atrium in MS, with normal peripheral blood levels. The aim of the present study was to assess regional left atrial and systemic coagulation activities by measuring PF1+2 in patients with severe mitral stenosis and sinus rhythm, normal blood clotting times, and no left atrial thrombus. The study was conducted in 25 consecutive patients with moderate-to-severe MS and sinus rhythm who underwent percutaneous balloon mitral valvuloplasty. Transesophageal echocardiography was performed before the valvuloplasty procedure in all patients to exclude the presence of left atrial thrombus and left atrial spontaneous echo contrast (LASEC). There were no statistically significant differences between LASEC-positive and LASEC-negative patients with respect to age, gender, fibrinogen levels, prothrombin time, mitral valve area, mean mitral gradient, pulmonary artery pressure (in all p > 0.05). Regional (left atrial) PF1+2 levels of both LASEC-positive and LASEC-negative patients were significantly elevated when compared to control subjects (p < 0.01). Statistically significant elevated systemic level of PF1+2 was observed only in LASEC-positive patients when compared to control subjects (p < 0.01, p > 0.05, respectively). In conclusion patients with severe mitral stenosis and SR have increased regional coagulation activity in both LASEC-negative and LASEC-positive groups. Although this increased regional coagulation activity has been reflected in peripheral blood of LASEC-positive patients, it has not been reflected in peripheral blood of LASEC-negative patients.Öğe Predictors of left ventricular thrombus formation in patients with dilated cardiomyopathy: role of activated protein C resistance(Lippincott Williams & Wilkins, 2004) Erbay, AR; Turhan, H; Senen, K; Yetkin, F; Ayaz, S; Kara, F; Buyukasik, NSObjectives The aim of this study was to investigate the association between left ventricular thrombus formation and natural anticoagulant systems including the protein C, protein S and antithrombin in patients with dilated cardiomyopathy. Materials and methods Sixty patients with dilated cardiomyopathy who met the inclusion criteria were included in the study. Patients were divided into two groups: group I consisted of 22 patients with left ventricular thrombus and group II consisted of 38 patients without left ventricular thrombus. Our main inclusion criteria were ejection fraction less than or equal to 35% and left ventricular end-diastolic diameter greater than or equal to 6.0 cm. These two groups were compared for clinical and hematologic parameters (activated protein C resistance, protein S and antithrombin). Results There were no statistically significant differences between patients with or without left ventricular thrombi with respect to left ventricular end-diastolic and end-systolic dimensions, ejection fraction, fractional shortening and left atrial diameter. There were no statistically significant differences between patients with and without left ventricular thrombus with respect to platelet count (252 +/- 64/mm(3) x 10(3) compared with 260 +/- 74/mm(3) x 10(3) respectively, P=0.68), prothrombin time (12.94 +/- 1.9s compared with 12.86 +/- 1.3 s respectively, P=0.82), activated partial thromboplastin time (32 +/- 5 compared with 30 +/- 4 s respectively, P= 0.32) and fibrinogen levels (36 +/- 9 mg/dl compared with 34 +/- 8 mg/dl respectively, P=0.41). None of the patients had protein S and antithrombin deficiency. Activated protein C resistance was found in 12 patients (12 out of 22, 54%) in group I and four patients (four out of 38, 9.5%) in group II (P < 0.01). It was also shown to be an independent predictor of left ventricular thrombus (P < 0.05). Conclusion Activated protein C resistance is found to be an independent predictor of left ventricular thrombus in patients with dilated cardiomyopathy who have ejection fractions less then 35% and left ventricular end-diastolic dimensions > 6.0 cm.