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Öğe The effect of isolated left bundle branch block on the myocardial velocities and myocardial performance index(WILEY, 2008) Duzenli, Mehmet Akif; Ozdemir, Kurtulus; Soylu, Ahmet; Aygul, Nazif; Yazici, Mehmet; Tokac, MehmetObjectives: This study was planned in order to investigate the effect of left bundle branch block (LBBB) on myocardial velocities obtained by tissue Doppler echocardiography (TDE) and myocardial performance index (MPI). Methods: Subjects with LBBB (n = 61) and age-matched healthy subjects (n = 60) were enrolled in the study. Left ventricular (LV) ejection fraction (EF), mitral inflow velocities (E-wave and A-wave), isovolumetric contraction and relaxation time (ICT and IRT), ejection time (ET), and flow propagation velocity (Vp) were measured by conventional echocardiography. Systolic velocity (Sm), early and late diastolic velocities (Em and Am) and time intervals were measured by TDE. MPI was calculated by the formula (ICT + IRT)/ET. Results: LVEF and mitral E/A ratio were similar in both groups. Vp was lower in the LBBB group than in the control group, whereas the E/Em and the E/Vp ratio was higher. LV Sm and Em/Am ratio were lower in LBBB group. Right ventricular Sm and Em/Am ratio were similar in both groups. LV mean and RV MPI were significantly increased in LBBB group. Conclusion: These findings obtained by TDE show that isolated LBBB impairs the ventricular functions. Both of the LV and RV dysfunctions shown by the new parameters may contribute to increased morbidity and mortality in cases with isolated LBBB.Öğe The Effect of Nondipping Blood Pressure Patterns on Cardiac Structural Changes and Left Ventricular Diastolic Functions in Normotensives(WILEY, 2009) Soylu, Ahmet; Duzenli, Mehmet Akif; Yazici, Mehmet; Ozdemir, Kurtulus; Tokac, Mehmet; Gok, HasanBackground: Cardiac structural changes have been reported to be more prominent in nondipper normotensives than the dipper ones. But the influence of nondipping status on cardiac diastolic functions of normotensives has not been studied yet. In this study, we investigated the effect of nondipping status on both cardiac structural changes and left ventricular (LV) diastolic functions in normotensives. Methods: We performed ambulatory blood pressure (BP) monitoring (ABPM) and echocardiography in 62 normotensive subjects with the following criteria: (1) office BP < 140/90 mmHg; (2) average 24-hour ambulatory BP < 130/80 mmHg. Results: In the evaluation by tissue Doppler imaging (TDI), the early diastolic myocardial peak velocity (Em) and Em/late diastolic myocardial peak velocity (Am) ratio (Em/Am ratio) were lower in nondippers than those in dippers (P = 0.009 and P < 0.001, respectively). Isovolumic relaxation time (IRT) and myocardial performance index (MPI) were higher in nondippers than those in dippers (P = 0.036 and P = 0.026, respectively). Nondipping status, independent of other factors, was observed to cause both a decrease in the Em and Em/Am ratio and an increase in IRT. However, its effect on IRT was not statistically significant (coefficient = -0.27, P = 0.027; coefficient = -0.37, P = 0.002; coefficient = 0.20, P = 0.082, respectively). Conclusions: Nondipping of nocturnal BP seems to be a determinant of cardiac remodeling and LV diastolic dysfunction (LVDD) and may result in a cardiovascular (CV) risk independent of the increase in LV mass (LVM) in normotensives. (ECHOCARDIOGRAPHY, Volume 26, April 2009).Öğe Effects of Lipokit (R) Centrifugation on Morphology and Resident Cells of Adipose Tissue(SOC CHILENA ANATOMIA, 2013) Duman, Selcuk; Aktan, Tahsin Murad; Cuce, Gokhan; Cihantimur, Bulent; Tokac, Mehmet; Akbulut, HabipThe aim of adipose tissue engineering is creating autologus vascularized fat tissue to be used for practical soft tissue reconstruction in human clinic. Unfortunately, in practice, long-term results of fat transplantation are often untrustworthy and unreliable, to overcome this problem different many lipoinjection techniques developed in the last 20 years. Centrifuge is a fundamental step in the preparation of adipose tissue. We focused on some cell markers especially MSCs markers and histological structural properties after with lipokit centrifugation and without lipokit centrifugation of adipose tissue obtained by liposuction by this new technique. Adipose tissue was taken by liposuction and separates to two portions. One of them is centrifugated by Lipokit machine (C+) has a micro filter and the other is not (C-). After centrifugation smear slides and paraffin sections were prepared from these tissues. These slides were stained with H&E and Toluidine Blue. Paraffin sections were immunohistochemically stained with CD34, von Willebrand Factor, CD73, CD90 and CD105. Smear preparations showed a continuous three dimensional plasma membrane appearance of adipocytes. C+ and C-showed expression of CD34, von Willebrand Factor, CD73, CD90, CD105. C+ seems to have more free cells expressing than C-. While passing the filter of Lipokit, large adipocytes and connective tissue parts disintegrate and thus increases the surface area of lipoaspirate. Lipokit (R) machine release the group cells which are necessary for angiogenesis and they become more freely to construct angiogenesis.Öğe Effects of menopause on the myocardial velocities and myocardial performance index(JAPANESE CIRCULATION SOC, 2007) Duzenli, Mehmet Akif; Ozdemir, Kurtulus; Sokmen, Abdullah; Soylu, Ahmet; Aygul, Nazif; Gezginc, Kazim; Tokac, MehmetBackground Although menopause is known to increase cardiovascular risk and mortality, the effect of menopause on cardiac functions has not been investigated in detail. This study investigates the effect of menopause on cardiac functions by tissue Doppler echocardiography (TDE) and myocardial performance index (MPI). Methods and Results A total of 72 postmenopausal and 71 age-matched premenopausal women were enrolled in the study. After conventional echocardiographic parameters were measured, TDE recordings were obtained at the septal, lateral, anterior and inferior side of the mitral annulus, and tricuspid lateral annulus. Systolic velocity (Sm), early and late diastolic velocities (Em and Am) and time intervals were measured and MPI was calculated. A sequentially symptom-limited exercise stress test was performed. Although left ventricular (LV) ejection fraction and end-diastolic and end-systolic diameter were similar in both groups, LV septum and posterior wall thickness were higher in postmenopausal women. Mitral early inflow velocity and mitral early inflow velocity:mitral late inflow velocity ratio were significantly lower in postmenopausal women compared to premenopausal women. LV Sm, and LV and right ventricular (RV) Em:Am ratios were lower in postmenopausal women. MPI calculated by TDE was significantly increased in postmenopausal women. In addition, exercise duration and metabolic equivalent values were significantly lower in postmenopausal women than in premenopausal women. Conclusions Menopause negatively affects MPI and myocardial velocities, both of which provide more quantitative data about myocardial functions. These findings indicate that the hormonal changes in menopause impair LV systolic and diastolic functions and RV diastolic function.Öğe Glutathione S-transferase M1 and T1 genotypes and myocardial infarction(SPRINGER, 2013) Cora, Tulin; Tokac, Mehmet; Acar, Hasan; Soylu, Ahmet; Inan, ZiyaMyocardial infarction (MI), which is the most important manifestation of coronary artery disease, is the leading cause of morbidity and mortality in the world. Glutathione S transferases (GSTs) are enzymes responsible for the metabolism of numerous xenobiotics and are known to be polymorphic in humans. We investigated the association between the GSTM1 and GSTT1 gene polymorphisms and MI. The study consists of 296 healthy controls and 324 consecutive patients who had undergone coronary angiography for suspicion of coronary artery disease and with a past history of myocardial infarction. DNA was extracted from whole blood of patient and control. GSTM1 and GSTT1 gene polymorphisms were examined using multiplex PCR. We found that the null GSTM1 was associated with protective effect on MI, although this increase was not significant for GSTM1 (p < 0.054). However, GSTT1 genotype was associated with an increase in the risk of developing MI. In addition to after adjusting other all coronary risk factors, the interactive effect of GSTT1 null genotype remained statistically significant (p < 0.001) for MI disease but GSTM1 null genotype was not statistically significant. Patients, who smoke having the null genotypes of GSTM1, were at a higher risk for developing MI (p < 0.001, OR = 0.41, 95 % CI = 0.240-0.207). There was an effect of interaction of GSTM1 null genotype and smoking on MI development between patient and control groups (p < 0.001). Our results showed that individuals with the null genotypes for GSTM1 had protective effect, while GSTT1 was at a higher risk for MI disease. In addition, there was additional effects of smoking when smoking and non-smoking groups were compared.Öğe Impact on Diabetes Mellitus on the Epicardial Coronary Flow Velocity Assessed by the Thrombolysis in Myocardial Infarction Frame Count(SAGE PUBLICATIONS INC, 2009) Soylu, Ahmet; Ozdemir, Kurtulus; Duzenli, Mehmet Akif; Yazici, Mehmet; Tokac, MehmetThe aim of this study is to evaluate the effect of type 2 diabetes mellitus on epicardial coronary flow velocity assessed by the thrombolysis in myocardial infarction frame count. The thrombolysis in myocardial infarction Frame count was measured in 272 coronary arteries from 101 patients with type 2 diabetes mellitus and in 271 coronary arteries from 104 age- and gender-matched patients without type 2 diabetes mellitus referred for coronary angiography. The thrombolysis in myocardial infarction frame count was measured only in normal arteries or in arteries Without significant lesion. By both univariate and multivariate analysis, the thrombolysis in myocardial infarction frame count was not related with either type 2 diabetes mellitus or the duration and glycated hemoglobin levels in the patients with type 2 diabetes mellitus. The thrombolysis in myocardial infarction Frame Count Was significantly associated with body surface area, heart rate, and proximal coronary artery diameter. Type 2 diabetes mellitus did not affect epicardial coronary flow velocity assessed by the thrombolysis in myocardial infarction frame count.Öğe Influence of menstrual cycle on cardiac performance(ELSEVIER IRELAND LTD, 2007) Zengin, Kadriye; Tokac, Mehmet; Duzenli, Mehmet Akif; Soylu, Ahmet; Aygul, Nazif; Ozdemir, KurtulusObjectives: The purpose of this study was to investigate the relationship between endogen sex hormone levels and myocardial performance in two different phases of menstrual cycle. Background: The relationships between cardiac performance and sex hormone levels in menstrual cycle have not yet been clearly identified. Methods: Twenty-seven women at the age of 19-42 years (mean 24.11 +/- 6.02) with regular menstrual cycles (28-31 days) were enrolled in this study. Cardiac performance was evaluated by tissue Doppler imaging (TDI) derived myocardial performance index (MPI) in the menstrual and the luteal phases of the menstrual cycle. Results: Left ventricular MPI were statistically significant between the menstrual phase and luteal phase of the menstrual cycle (Inferior 0.53 +/not superset of 0.10 versus 0.44 +/not superset of 0.09, P < 0.001; Anterior 0.54 +/not superset of 0.13 versus 0.45 +/not superset of 0.10, P < 0.008; Lateral 0.50 +/not superset of 0.09 versus 0.44 +/not superset of 0.12, P < 0.03; Septum 0.54 +/not superset of 0.07 versus 0.46 +/not superset of 0.10, P < 0.005; Global 0.52 +/not superset of 0.06 versus 0.44 +/not superset of 0.09, P < 0.001). Right ventricle MPI between the two periods was also significantly different (0.49 +/not superset of 0.10 versus 0.42 +/not superset of 0.10, P < 0.01). There was a moderate correlation between estrogen levels and global NIPI (r=0.46, P=0.001), but no correlation was found between progesterone levels and global MPI (r = 0.22, P = NS). Conclusion: We firstly demonstrated that endogen estrogen or progesterone improved the combined systolic and diastolic function in both left and right ventricle during luteal phases of menstrual cycle. Considering the previous studies and our results, estrogen may be responsible for this improvement. (c) 2007 Elsevier Ireland Ltd. All rights reserved.Öğe Platelet glycoprotein Ib alpha gene polymorphism and massive or submassive pulmonary embolism(SPRINGER, 2009) Soylu, Ahmet; Tokac, Mehmet; Cora, Tuelin; Duzenli, Mehmet Akif; Acar, HasanObjective The -5T/C polymorphism in the Kozak sequence of glycoprotein Ib alpha, a component of the platelet glycoprotein Ib-IX-V receptor complex, is associated with an increase in this receptor density on the surface of the platelet. This study was designed to investigate the effect of platelet glycoprotein Ib alpha Kozak polymorphism on the clinical presentation of the patients with acute pulmonary embolism. Methods Forty-two patients with pulmonary embolism were genotyped for Kozak polymorphism of the glycoprotein Ib alpha by polymerase chain reaction/restriction fragment length polymorphism. Results Carriers of the -5T/C polymorphism of glycoprotein Ib alpha were significantly over-represented in the patient group with clinically massive or submassive pulmonary embolism (odds ratio 5.5, 95% confidence interval 1.4 to 22.2, P = 0.023). Also the association between this polymorphism and massive or submassive pulmonary embolism still existed even after being adjusted for conventional risk factors. Conclusion The -5T/C polymorphism in the Kozak sequence of glycoprotein Ib alpha may present as a risk factor for clinical manifestation of pulmonary embolism in which clot burden plays an important role.Öğe Relation Between Abnormalities in Circadian Blood Pressure Rhythm and Target Organ Damage in Normotensives(JAPANESE CIRCULATION SOC, 2009) Soylu, Ahmet; Yazici, Mehmet; Duzenli, Mehmet Akif; Tokac, Mehmet; Ozdemir, Kurtulus; Gok, HasanBackground: To determine the individual effect of abnormalities in blood pressure (BP) circadian rhythm (non-dipping status (NDS), increased morning BP (MBP) or increased MBP surge (MBPS)) on target organ damage (TOD) and which of these is more closely related to TOD in normotensives. Methods and Results: The 24-h ambulatory BP monitoring (ABPM) and echocardiography were performed and urinary albumin excretion (UAE) was measured in 47 dipper (28 women, mean age 45.8 +/- 9.3) and 32 non-dipper (25 women, mean age 49.1 +/- 8.3 years) normotensive subjects. The left ventricular mass index (LVMI) was higher in non-dipper group (103.8 +/- 24.1 vs 91.6 +/- 23.5 g/m(2), 12, P=0.03). UAE in non-dipper group was higher, but the difference between the two was not statistically significant (18.9 [10.3, 28.9] vs 14.1 [7.5, 23.8], P=0.11). In multivariate analysis, both LVMI and UAE were affected by NDS and MBP independent of other confounding variables (for LVMI; Coefficient=0.27, P=0.01 and Coeffcient=0.37, P=0.001, respectively, and for UAE; Coefficient=0.27, P=0.02 and Coefficient =0.28, P=0.01, respectively). Conclusions: It may be Postulated that increased night and MBP are the factors that cause TOD, and it seems reasonable to attempt to restore normal diurnal rhythm of the BP even in normotensive Subjects. (Circ J 2009; 73: 899-904)Öğe SPECIAL ATTENTION FOR ELDERLY WOMEN: ATYPICAL LEFT VENTRICULAR APICAL BALLOONING SYNDROME INDUCED BY DOBUTAMINE STRESS TEST: A CASE REPORT(WILEY-BLACKWELL PUBLISHING, INC, 2009) Sonmez, Osman; Duman, Cetin; Duzenli, Mehmet Akif; Tokac, Mehmet[Abstract not Available]Öğe Usefulness of Coronary Angiography for Assessing Left Ventricular Systolic Function(ACTA CARDIOLOGICA, 2001) Özdemir, Kurtuluş; Altunkeser, Bülent Behlül; Sökmen, Gülizar; Şahingeri, Mustafa; Tokac, Mehmet; Telli, Hasan H.; Gök, HasanObjective - In previous echocardiographic studies, a correlation between ejection fraction of the left ventricle and change in the movement of the mitral annular ring was found. In the light of these studies, we planned to investigate the relationship between systolic shortening (SS) and percent of systolic shortening (PSS), calculated from the long axis frame in coronary angiography and left ventricular systolic function. Methods and results - One hundred and thirty-eight patients (40 men and 98 women; mean age 58 +/- 10 years) who had been referred for coronary angiography and left ventriculography were included in the study. Ejection fraction (EF) was calculated from left ventriculography obtained from 30 degrees right anterior oblique projection. Distance from the lower border of the ostium of the left coronary artery to the most apical border of the left anterior descending (LAD) artery was measured at end-systole (ES) and end-diastole (ED) using coronary angiography obtained from the same projection. SS as ED-ES and PSS as SS/ED were calculated. Correlation of SS and PSS with EF was calculated (EF = 13.7 + 4.8 x SS, r = 0.91, p < 0.001 and EF = 14.2 + 6.5 x PSS, r = 0.90, p < 0.01). SS < 7 mm (criterion A) and PSS < 6% (criterion B) suggested that left ventricle EF was less than 50%, with a sensitivity, specificity and diagnostic accuracy of 83%, 100%, 95%; 95%, 86% and 88%, respectively. Conclusion - SS and PSS highly significantly correlate with left ventricular EF Therefore, left ventriculography could be omitted in selected patients undergoing coronary angiography if it is not necessary to define the anatomic structure of the left ventricle.
