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Dive into the research topics where Dursun Çayan Akkoyun is active.

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Featured researches published by Dursun Çayan Akkoyun.


The Anatolian journal of cardiology | 2014

Heart rate recovery may predict the presence of coronary artery disease

Aydın Akyüz; Seref Alpsoy; Dursun Çayan Akkoyun; Hasan Değirmenci; Niyazi Güler

OBJECTIVE We investigated whether post-exercise first minute abnormal heart rate recovery (HRR1) helps to predict the presence and severity of CAD, because of some confounding data. METHODS A cross-sectional, retrospective study was performed. Two hundred individuals were included. Gensini scores and the number of coronary artery involvements were used to evaluate the severity of CAD. Students t-test, Mann-Whitney U test and chi-square test were used for the analysis continuous and categorical data. Spearmans correlation analysis was used to determine whether there is correlation between Gensini scoring and HRR1. Univariate and multivariate logistic regression were used to determine predictors for abnormal HRR1. ROC curve analysis was performed to detect the best sensitivity and specificity value of HRR1 in predicting CAD presence. RESULTS Seventy subjects (35%) did not have CAD, and CAD was present in 130 patients (65%). HRR1 ≤21 beats with ROC analysis was determined to be the best cut off point. After adjustment between the two groups in terms of age, gender, diabetes, hypertension, dyslipidemia or smoking (all p>0.05), there was relationship CAD presence and abnormal HRR1 (OR=2.1, 95% CI: 1.1-3.9, p=0.02), but not between CAD severity and HRR1 (r=-0.13, p=0.112). The sensitivity, specificity, and the positive and negative predictive values of abnormal HRR1 ≤21 beats at first minute for predicting CAD presence were 76.1%, 41.3% (AUC=0.588, CI 95%: 0.517-0,657, p=0.039), 70.7% and 48.3%, respectively. CONCLUSION In the study abnormal HRR1 predicted the presence of CAD, but not the severity of it.


Angiology | 2016

Effect of CPAP on New Endothelial Dysfunction Marker, Endocan, in People With Obstructive Sleep Apnea

Nejat Altintas; Levent Cem Mutlu; Dursun Çayan Akkoyun; Murat Aydin; Bulent Bilir; Ahsen Yilmaz; Atul Malhotra

Obstructive sleep apnea (OSA) is associated with increased cardiovascular (CV) morbidity and mortality. Endocan is a surrogate endothelial dysfunction marker that may be associated with CV risk factors. In this study, we tested whether serum endocan is a biomarker for OSA. Serum endocan levels were measured at baseline in 40 patients with OSA and 40 healthy controls and after 3 months of continuous positive airway pressure (CPAP) treatment in the patients with OSA. All participants were evaluated by full polysomnography. Flow-mediated dilatation (FMD) and carotid intima media thickness (cIMT) were measured in all participants. Endocan levels were significantly higher in patients with OSA than in healthy controls. After adjusting confounders, endocan was a good predictor of OSA. Endocan levels correlated with OSA severity (measured by the apnea–hypopnea index [AHI]). After 3 months of CPAP treatment, endocan levels significantly decreased. Endocan levels were significantly and independently correlated with cIMT and FMD after multiple adjustments. The cIMT and FMD also had significant and independent correlation with AHI. Endocan might be a useful marker for the predisposition of patients with OSA to premature vascular disease.


Angiology | 2014

Association Between Serum Fetuin-A levels, Carotid Artery Stiffness, and Intima–Media Thickness in Patients With Normotensive Obstructive Sleep Apnea Syndrome

Aydın Akyüz; Mustafa Oran; Seref Alpsoy; Levent Cem Mutlu; Dursun Çayan Akkoyun; Savas Guzel; Recep Alp

Increased carotid intima–media thickness (cIMT) and stiffness, reflecting subclinical atherosclerosis, are associated with obstructive sleep apnea syndrome (OSAS). The relationship between serum fetuin-A, which inhibits ectopic calcification, and atherosclerosis is unclear. Therefore, we investigated the association between serum fetuin-A levels and carotid artery stiffness and cIMT in patients with normotensive OSAS (n = 50) and non-OSAS controls (n = 38). Compared with controls, there were lower fetuin-A levels (59.4 ± 6.5 vs 68.2 ± 5.8 ng/mL, P = .029), higher mean cIMT (0.73 ± 0.2 vs 0.63 ± 0.3 mm, P < .001), and greater stiffness (β) index (7.45 ± 0.9 vs 5.2 ± 0.7, P = .001) in the OSAS group. The cIMT and stiffness (β) index were inversely correlated with fetuin-A levels (r = −.324, P = .033; r = −.466, P < .001, respectively) and positively correlated with apnea hypopnea index (r = .498, P < .001; r = .422, P = .001, respectively) in the OSAS group. Decreased serum fetuin-A levels were associated with subclinical carotid atherosclerosis in patients with normotensive OSAS.


Angiology | 2015

Atrial Fibrillation Is Associated With Increased Mean Platelet Volume and Apnea Hypopnea Index in Patients With Obstructive Sleep Apnea.

Aydın Akyüz; Dursun Çayan Akkoyun; Hasan Değirmenci; Recep Alp

This study investigated whether there is a relationship between atrial fibrillation (AF), mean platelet volume (MPV), and apnea hypopnea index (AHI) in patients who have obstructive sleep apnea syndrome (OSAS). We enrolled patients who had OSAS with either AF or normal sinus rhythm (NSR). We divided 90 patients (aged 50-80 years) into 2 groups: group 1 consisted of 40 patients with OSAS having AF and group 2 of 50 patients with OSAS having NSR. Mean platelet volume was higher in patients with AF than in those with NSR (9.8 ± 0.6 vs 8.4 ± 0.6 fL; P < .001). The MPV and AHI were substantial variables associated with AF (odds ratio [OR] = 2.41; 95% confidence interval [CI], 1.36-5.26; P < .004 and OR = 1.91; 95% CI, 1.26-3.32; P = .02). Elevated MPV value of ≥9.4 fL is associated with AF (70% sensitivity and 63% specificity). More research is needed to establish the clinical relevance of this association.


Angiology | 2016

Rosuvastatin Decreases Mean Platelet Volume in Patients With Diabetes Mellitus

Aydın Akyüz; Dursun Çayan Akkoyun; Hasan Değirmenci; Mustafa Oran

Statins have multiple effects (also known as pleiotropic effects) on inflammation, plaque stabilization, endothelial function, and hemostasis. We evaluated the effects of rosuvastatin on mean platelet volume (MPV)—a marker for platelet activity—in patients with diabetes mellitus (DM) on rosuvastatin medication. Patients (n = 178) who were to be prescribed high-intensity rosuvastatin were retrospectively enrolled according to their medical records. Baseline and 6-month biochemical tests, automated blood count, cell-volume analysis, and their cardiovascular risk factors were recorded. Rosuvastatin significantly reduced the MPV and the lipid parameters including total cholesterol, triglyceride, and low-density lipoprotein cholesterol (LDL-C). However, there was no correlation between MPV and LDL-C before (r = −.66; P = .383) and after (r = −.112; P = .135) rosuvastatin treatment or between ΔMPV and ΔLDL-C after 40 mg rosuvastatin daily therapy (r = −.155; P = .073). Rosuvastatin significantly decreases the MPV as well as cholesterol levels. The antiplatelet activation properties of high-dose rosuvastatin treatment in patients with DM are not lipid dependent.


Cardiology Journal | 2014

Serum fetuin-A levels are associated with carotid intima–media thickness in patients with normotensive chronic obstructive pulmonary disease

Seref Alpsoy; Aydın Akyüz; Levent Cem Mutlu; Mustafa Oran; Dursun Çayan Akkoyun; Hasan Değirmenci; Savas Guze

BACKGROUND There are contradictory reports about the relationship between fetuin-A and atherosclerotic process. Coronary artery disease is the most important cause of mortality in patients with chronic obstructive pulmonary disease (COPD). We aimed to investigate the association of serum fetuin-A level with mean carotid intima-media thickness (cIMT) and ankle-brachial index (ABI) in COPD. METHODS We evaluated the association of serum fetuin-A level, mean cIMT and ABI in normotensive subjects with COPD (n = 65) and with non-COPD (n = 50). RESULTS Fetuin-A level was significantly lower (63.5 ± 19.8 ng/mL, 72.9 ± 16.2 ng/mL, p = 0.035) and C-reactive protein level higher (4 [1-10] vs. 3 [1-12] mg/dL, p = 0.034) in COPD patients than the control group. Compared to controls, fetuin-A level was significantly lower (63.5 ± 19.8 ng/mL, 72.9 ± 16.2 ng/mL, p = 0.035) and mean cIMT higher (0.69 [0.50-0.98] vs. 0.62 [0.44-0.98] mm, p = 0.034, respectively) in the COPD group. There was a significant negative correlation between mean cIMT and fetuin-A levels (r = -0.320, p = 0.032). Age (b ± SE: 0.002 ± 0.001, p = 0.008) and fetuin-A (b ± SE: -0.002 ± 0.001, p = 0.035) were decisive for the mean cIMT. CONCLUSIONS There are increased cIMT values, decreased fetuin-A levels, but unchanged ABI values in patients with normotensive COPD. Age and fetuin-A were predictors for cIMT, while fetuin-A was negatively correlated with cIMT.


Türk Kardiyoloji Derneği arşivi : Türk Kardiyoloji Derneğinin yayın organıdır | 2015

Relationship between red cell distribution width and contrast-induced nephropathy in patients who underwent primary percutaneous coronary intervention.

Dursun Çayan Akkoyun; Aydın Akyüz; Ömer Kurt; Bulent Bilir; Şeref Alpsoy; Niyazi Güler

OBJECTIVE This study evaluated the relationship between contrast-induced nephropathy (CIN) and red cell distribution width (RDW) in patients who underwent primary percutaneous coronary intervention (PCI). METHODS A total of 359 patients with ST elevation myocardial infarction (STEMI) who had undergone primary PCI were included in the study. An increase of 25% in serum creatinine value after 48 h, or an increase of >0.5 mg/dL in the basal value was defined as CIN. RESULTS Of the patients included in the study, 49 (13.8%) developed CIN. Compared to the CIN-negative group, CIN-positive patients had increased RDW values (16.9 ± 2.00 and 14.8 ± 2.14 respectively, p<0.001). The latter were also older patients, and had increased age rates of diabetes mellitus, baseline creatinine, ∆-creatinine and amount of contrast media were higher and left ventricular ejection fraction and baseline glomerular filtration rate (GFR) were lower in the CIN-positive group than in the CIN-negative group. A statistically weak correlation was found between RDW and change in creatinine levels (∆-creatinine) (r=0.250, p=0.002). Diabetes mellitus (odds ratio [OR]: 3.252, 95% CI=1.184-8.951, p=0.022), high RDW (OR: 1.716, 95% CI=1.363-2.157, p<0.001), baseline low GFR (OR: 0.941, 95% CI=0.925-0.971, p<0.001), ∆-creatinine (OR: 1.197, 95% CI=1.061-2.986, p=0.006) and increased amount of contrast media (OR: 1.187, 95% CI=1.048-3.02, p=0.001) used were observed as independent predictors of CIN. CONCLUSION The study found diabetes mellitus, high RDW, basal low GFR, ∆-creatinine and increased contrast amount used to be the independent predictors of CIN in STEMI patients who underwent PCI.


Korean Circulation Journal | 2013

Spontaneous coronary artery dissection and woven coronary artery: three cases and a review of the literature.

Aydın Akyüz; Seref Alpsoy; Dursun Çayan Akkoyun

Spontaneous coronary artery dissection (SCAD) and woven coronary artery anomaly (WCAA) are relatively rare. A few of the previously reported woven coronary artery cases have involved in a single coronary artery. We present an unusual woven case involving all coronary arteries and two patient with SCAD. We have also reviewed the literature related to these disease, as they resemble one another.


Cardiology Research and Practice | 2014

Mean Platelet Volume in Patients with Obstructive Sleep Apnea and Its Relationship with Simpler Heart Rate Derivatives

Aydın Akyüz; Dursun Çayan Akkoyun; Mustafa Oran; Hasan Değirmenci; Recep Alp

Some studies show increased mean platelet volume (MPV) in obstructive sleep apnea (OSA). The aim of this study was to evaluate MPV in OSA patients without cardiovascular risk factors and the possible association of heart rate derivatives with MPV. A total of 82 patients (aged 30–70 years) were divided into 2 groups according to the presence of either OSA or non-OSA as the control group. The OSA group consisted of 52 patients and the control group consisted of 30 subjects. Neither group was significantly different in terms of MPV values as well as heart rate (HR) derivatives such as minimum HR, maximum HR, the difference between maximum HR and minimum HR, mean HR, and heart rate performance index (HRPI) [(HR max. − HR min.)/HR mean] (P > 0.05 for all variables). In multivariate analysis, platelet count and percentages of recording time spent at arterial oxygen saturation < 90% significant variables are associated with MPV (β ± SE: −0.004 ± 0.002, 95% CI, −0.008 to −0.001; P = 0.034) and (β ± SE: 2.93 ± 1.93, 95% CI, 0.167 to 5.69; P = 0.038). Consequently, our findings predominantly suggest that there is a casual and reciprocal interaction between MPV and autonomic activation.


Korean Circulation Journal | 2013

Maximal Exercise-Corrected QT as a Predictor of Coronary Artery Disease: Comparison of Simpler Heart Rate Corrections

Aydın Akyüz; Seref Alpsoy; Dursun Çayan Akkoyun; Hasan Değirmenci; Niyazi Güler

Background and Objectives The relationship between QT prolongation and myocardial ischemia is widely known. Due to the limited value of ST depression, we aimed to evaluate, by using four simpler heart rate corrections (Bazett, Framingham, Fridericia and Hodges), the value of maximal exercise-QTc prolongation in the diagnosis of coronary artery disease (CAD) presence and severity. Subjects and Methods We enrolled 234 subjects (mean age 57.3±9 years, 143 men) who had undergone exercise testing and coronary angiography due to a suspicion of CAD in the study. Evaluating CAD severity with Gensini scoring, the CAD group (n=122) and controls with non-CAD were compared in terms of corrected QT duration at maximal exercise. Results Age, gender, hypertension, dyslipidemia, smoking, exercise duration, resting, and peak heart rate were similar between the two groups (all p>0.05). The CAD group had higher raw QT values than the controls {268 (169-438) vs. 240 (168-348), p<0.001}. Although Framingham QTc of ≥350 ms and Fridericia QTc of ≥340 ms were seen to be useful for the diagnosis of CAD, there was no additive diagnostic value of exercise QTc in addition to ST depression. Maximal exercise-QTc Bazett (r=0.163, p=0.01), Framingham (r=0.239, p=0.001), and Fridericia (r=0.206, p=0.001) equations were weakly positively correlated with Gensini scoring. Conclusion The patients with CAD have longer QTc intervals at peak heart rates during exercise. This finding provides insufficient evidence to support routine incorporation of QTc at peak heart rates into exercise test interpretation.

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