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Bunyamin Yavuz

Publications and source records attributed to Bunyamin Yavuz.

11 recordsLinked to original sources
PubMed2006

Increased myocardial vulnerability and autonomic nervous system imbalance in obstructive sleep apnea syndrome.

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is characterized by the repeated episodes of upper airway obstruction during sleep, leading to significant hypoxia. Noninvasive evaluation of autonomic nervous system (ANS) and myocardial vulnerability may help determination of OSAS patients who are under high risk of malignant cardiac arrhythmias. The aim of this study was to show the effects of OSAS on predictors of arrhythmias by the evaluation of heart rate turbulence (HRT), heart rate variability (HRV) and QT dynamicity reflecting the ANS balance and myocardial vulnerability. METHODS: After polysomnographic study, 80 patients with OSAS and 55 age matched OSAS (-) subjects were included in the study. Twenty-four-hour Holter monitoring was performed in all subjects. HRT, HRV and QT dynamicity parameters were calculated. RESULTS: Turbulence slope was significantly decreased in OSAS patients whereas turbulence onset was increased (P<0.001). QT/RR slopes were significantly increased for QT end and QT apex (P<0.001). In HRV analysis, autonomic balance changed in favor of sympathetic system at night in OSAS patients. Furthermore, HRT and QT dynamicity parameters are found to be correlated with Apnea-Hypopnea Index (AHI). CONCLUSION: OSAS is associated with a significant worsening in HRV, HRT, and QT dynamicity parameters. Our results may indicate that HRV and QT dynamicity parameters can be useful noninvasive methods that may detect autonomic nervous system activity and ventricular vulnerability in OSAS.

Aged↗
PubMed2006

Novel cardiovascular risk factors and cardiac event predictors in female inactive systemic lupus erythematosus patients.

Systemic lupus erythematosus (SLE) is associated with severe and premature cardiovascular disease, which cannot be explained by traditional risk factors alone. This study aims to investigate novel cardiovascular risk factors and cardiac event predictors in inactive SLE female patients who do not have any major cardiovascular risk factors. Twenty-five inactive (SLE disease activity index score <4) SLE female patients and 22 healthy control women were studied. SLE patients with a history of diabetes mellitus, hypertension, hyperlipidemia, smoking, or coronary artery disease (CAD) were excluded. Venous blood samples were analyzed for lipid subfractions and novel cardiovascular risk factors such as lipoprotein (a), homocysteine, fibrinogen, high-sensitivity C-reactive protein (hs-CRP), and serum amyloid A (SAA) levels. Endothelial dysfunction was assessed by flow-mediated dilatation (FMD) from the brachial artery at baseline and during reactive hyperemia. SLE patients and controls were similar in terms of age (40+/-10 years vs 38+/-10 years, p = NS). No significant difference was found between the groups regarding family history of premature CAD, blood pressure, body mass index, lipoprotein (a), homocysteine, fibrinogen, SAA, apoprotein A-1 and B levels. Compared with the controls, SLE patients had higher levels of hs-CRP [median (range): 1.82 (0.02-0.98) vs 0.68 (0.02-0.35), p=0.04]. FMD was lower in SLE patients than controls (7.1+/-2.1 vs 11.4+/-1.2%, p<0.001). Increased levels of hs-CRP and decreased FMD were found in inactive SLE patients. Increased hs-CRP levels may reflect ongoing low-grade inflammation that could be a cause of impaired FMD in SLE patients. These findings suggest that SLE patients without traditional major cardiovascular risk factors may have increased risk of cardiovascular disease and future cardiac events.

Adult↗
PubMed2006

QT dispersion increases in patients with systemic lupus erythematosus.

Although autopsy studies have documented that heart is affected in most of systemic lupus erythematosus (SLE) patients, clinical manifestations occur in less than 10%. QT dispersion, a new parameter that can be used to assess homogeneity of cardiac repolarization and autonomic function, has not been studied in SLE patients. The aim of our study was to evaluate the QT dispersion (QTd) in SLE patients without overt cardiac involvement. Eighty-three patients with a diagnosis of SLE (mean age 41+/-13) and age- and sex-matched 77 healthy control subjects (mean age 43+/-10) were enrolled in the study. All subjects had their complete history taken, laboratory examination, and transthoracic echocardiography (ECG). Patients with cardiac disease, hypertension, diabetes, or taking medications that may effect QTd or any ECG abnormalities were excluded. Resting 12-lead ECG were recorded for measurement of QTd. None of the patients and control subjects had overt cardiac involvement. The mean SLE duration was 86.5+/-15.4 months. QT dispersion was significantly greater in SLE patients than incontrol subjects (55.2+/-24.7 vs 20.7+/-5.3 ms, respectively; p<0.001). There was no correlation between QTd and duration of SLE, SLEDAI-K score, corticosteroid usage, and presence of anti SS-A antibody. QT dispersion is significantly increased in SLE patients without overt cardiac involvement. Our result suggests that prolonged QT dispersion can be a useful noninvasive and simple method for early detection of cardiac involvement in SLE patients.

Adult↗
PubMed2006

Coronary artery bypass grafting is associated with a significant worsening of QT dynamicity and heart rate variability.

BACKGROUND: Imbalance in autonomic nervous system and impaired myocardial repolarization has been shown to increase the risk for arrhythmias in patients with coronary artery disease. This study evaluated the effects of coronary artery bypass grafting (CABG) on heart rate variability and QT interval dynamicity in subjects with coronary artery disease undergoing elective CABG surgery. METHODS: The study group consisted of 68 consecutive patients (mean age +/-SD: 61 +/- 9 years) with coronary artery disease who underwent elective CABG. Twenty-four-hour Holter monitoring was performed 2-5 days before cardiac surgery and was repeated 10 days after CABG. ELATEC holter software was used to calculate heart rate variability and QT dynamicity parameters. All subjects had a complete history, laboratory examination and transthoracic echocardiography. RESULTS: All patients had beta-blocking agent medication pre- and postoperatively. Standard deviation of all NN intervals for a selected time period, square root of the mean of the sum of the squares of differences between adjacent RR intervals, the proportion of differences in successive NN intervals greater than 50 ms, normalized low-frequency power, and normalized high-frequency power were significantly decreased after CABG surgery, whereas low-frequency/high-frequency ratio was significantly increased after CABG. QT/RR slopes over 24 h were significantly increased after CABG surgery for QT end and QT apex (QTapex/RR: 0.16 +/- 0.13 vs. 0.28 +/- 0.19, p < 0.001; QTend/RR: 0.18 +/- 0.13 vs. 0.36 +/- 0.23, p < 0.001). CONCLUSION: This prospective study showed for the first time that CABG was associated with a significant worsening of heart rate variability and QT dynamicity parameters in the postoperative period.

Adrenergic beta-Antagonists↗
PubMed2006

Left and right ventricular function is impaired in Behçet's disease.

OBJECTIVES: Subclinical cardiac involvement may occur in patients with Behçet's disease (BD). The purpose of our study was to assess the noninvasive parameters of biventricular function derived from Doppler tissue imaging (DTI) of the tricuspid and mitral annular motion in BD. METHODS: Twenty-one patients with BD and 20 control subjects were enrolled in this study. All subjects were selected to exclude those with cardiovascular risk factors. Standard echocardiography and pulsed DTI were obtained in every patient. RESULTS: Peak systolic (13.71 +/- 2.09 vs 20.01 +/- 1.57, P < 0.001), peak early diastolic (11.26 +/- 2.52 vs 15.35 +/- 2.06, P < 0.001) tricuspid annular velocities were significantly lower in patients than controls. Peak systolic (8.68 +/- 1.4 vs 12.25 +/- 1.7, P < 0.001), peak early diastolic (7.89 +/- 1.07 vs 9.94 +/- 1.12, P < 0.001), and peak end diastolic (8.30 +/- 1.32 vs 9.23 +/- 0.91, P = 0.013) lateral mitral annular velocities were significantly lower in patients than controls. CONCLUSIONS: We demonstrated that myocardial velocities, were affected in patients with BD. Therefore, we conclude that right and left ventricular function is impaired in patients with BD.

Adult↗
PubMed2006

QT dispersion increases with aging.

BACKGROUND: Age-related changes in cardiovascular system are well-known. Arrhythmias in elderly patients constitute most of the urgencies, consultations, or hospitalizations. QT dispersion (QTd) is a simple noninvasive arrhythmogenic marker to demonstrate the electrical instability of the heart. The aim of this study was to investigate how QTd changes with increasing age by calculating the QTd in the elderly and younger subjects. METHODS: One hundred and forty-six consecutive subjects (62 males and 84 females; age range: 18-82 years) were enrolled in the study. Sixty-seven of the subjects were 65 years and over (mean age, 70 +/- 4), 79 were younger than 65 (mean age, 37 +/- 11). A 12-lead ECG was recorded. The longest and the shortest QT intervals were measured manually on these ECG recordings. QTd was calculated from the formula, QTd = QTmax - QTmin. RESULTS: Demographic features were similar between the two groups. QTd of the elderly group was found to be significantly higher than the younger group (35.6 +/- 15.6 in elderly, 24.2 +/- 12.4 in younger group, P < 0.001). A positive relationship was found between QTd and age (r = 0.415, P < 0.001). QTd was greater in female than in male (31.9 +/- 16.7 ms vs 26.0 +/- 11.3 ms, respectively, P = 0.018). CONCLUSIONS: Our study shows that QTd increases with advancing age. We think that long-term follow-up of these patients would be useful to show if there is any relationship between the clinical outcomes and the increase in QTd.

Adolescent↗
PubMed2006

Simvastatin treatment improves endothelial function and increases fibrinolysis in patients with hypercholestrolemia.

OBJECTIVES: Statins reduce cardiovascular events by cholesterol-lowering as well as nonlipid-related actions. Thrombin activatable fibrinolysis inhibitor (TAFI) is a recently identified independent risk factor of thrombosis. Endothelial dysfunction is also a strong predictor of cardiovascular events. The aim of this study was to assess the effects of simvastatin treatment on circulating TAFI concentrations and endothelial function in patients with hypercholesterolemia. METHODS: Thirty-five patients (19 female, mean age 48 +/- 7 years) with hyperlipidemia were recruited into the study. Simvastatin was administered, 40 mg daily, for eight weeks to all subjects. Study subjects did not receive any medication except for lipid-lowering therapy during the follow-up period. Endothelial function was evaluated by flow-mediated dilation (FMD) from the brachial artery of the patients. Plasma lipid parameters, TAFI levels and endothelial function were measured before and after simvastatin treatment. RESULTS: Treatment with simvastatin showed a significant decrement in plasma total cholesterol, LDL cholesterol and triglyceride levels (p<0.05). Plasma TAFI levels were also significantly decreased after simvastatin treatment [median 17.0 (range 0.4-93.7) mcg/mL versus median 6.9 (range 0.8-63.0) mcg/mL, p<0.001]. Mean FMD was measured 7.7 +/- 2.5% at baseline and significantly improved after treatment (13.0 +/- 1.4%) (p=0.001). CONCLUSION: Our findings of decreased TAFI levels may reflect the beneficial effect of simvastatin treatment on fibrinolysis, and improved endothelial function may suggest the improved future cardiovascular events in hyperlipidemic patients.

Anticholesteremic Agents↗
PubMed2006

Heart-type, fatty-acid binding protein can be a diagnostic marker in acute coronary syndromes.

OBJECTIVES: Chest pain is one of the most common complaints among patients admitted to emergency departments. Cardiac troponins, CK-MB and myoglobin, which are used routinely in the diagnosis of acute coronary syndrome (ACS), are not elevated in the initial hours of ACS--precluding their usefulness in the early diagnosis. The aim of this study is to determine the efficacy of H-FABP compared to myoglobin and CK-MB in the early diagnosis of ACS. METHODS: Sixty-seven patients with ACS were enrolled in the study. An initial blood sample was obtained for CK-MB, cTnT, myoglobin and H-FABP. At the fourth, eighth, and 12th hours, repeat ECGs and cardiac enzyme samples were obtained. H-FABP test was repeated at the fourth hour. RESULTS: H-FABP has sensitivity equal to that of CK-MB and superior to that of myoglobin (97.6%, 96.7%, 85.4%, respectively) on the first hour. This trend extends to the fourth hour of myocardial injury as well. H-FABP was more specific than CK-MB, myoglobin and troponin T at the first hour (38.5%, 34.6%, 34.6%, 23.1%, respectively), whereas its specificity at the fourth hour was equal to those of CK-MB and troponin T and exceeded that of myoglobin. CONCLUSIONS: It can be suggested that in patients with an initial diagnosis of ACS and within 20 hours from symptom onset, H-FABP levels may be measured. For this purpose, point-of-care H-FABP test may be utilized, which has the advantage of bedside testing and rapid test results.

Acute Disease↗
PubMed2006

Plasma osteopontin levels are elevated in non-ST-segment elevation acute coronary syndromes.

BACKGROUND: The regions of ruptured atherosclerotic plaques have numerous macrophages. Osteopontin that modulates macrophage function has been shown in atherosclerotic plaques. We aimed to study the plasma levels of osteopontin in patients with unstable angina or non-ST-seg ment elevation myocardial infarction (NSTEMI) and the rela tionship between osteopontin and the extent of the coronary artery disease (CAD). METHODS: We studied 65 patients with unstable angina or NSTEMI, 25 patients with stable angina and 18 patients as the control group. The extent of coronary artery stenosis was determined by the number of vessels with >50% stenosis. Plasma osteopontin concentrations were measured from the blood samples that were drawn immediately after admission to the emergency department in unstable angina/NSTEMI patients and before the coronary angiograph in the stable angina and control groups. RESULTS: The plasma osteopontin concentration was (495 118 ng/ml) significantly higher in the patients with unstable angina/NSTEMI compared to the stable angina group (319 106 ng/ml) and control group (125+/-54 ng/ml) (p=0.0001 The plasma osteopontin levels were lower in the patients with stable angina pectoris who had one-vessel disease compared to those with two-vessel disease (p=0.01). How ever, in the unstable angina/NSTEMI group, the plasma osteopontin levels were statistically not different among the patients with one-vessel, and two-vessel and three-vessel disease (p=NS). There was no correlation between the plasma osteopontin levels and the extent of coronary stenosis. CONCLUSIONS: The plasma osteopontin levels are elevatedin patients with unstable angina/NSTEMI, but there appears to be no correlation with the extent of CAD. These results ma suggest that osteopontin may have a role in the pathobiology of ACS.

Aged↗