Biomedical subjects

Harun Evrengül

Publications and source records attributed to Harun Evrengül.

10 recordsLinked to original sources

PubMed2005

Time and frequency domain analyses of heart rate variability in patients with epilepsy.

Heart rate variability (HRV) is a useful tool for the detection of sympathetic-parasympathetic balance of autonomic nervous system in patients at risk of sudden death (SD). SD is more common in patients with epilepsy and the exact mechanisms of SD are unknown. Autonomic nervous system involvement in patients with epilepsy has rarely been studied and has shown conflicting results. Our purpose was to determine if HRV showed any changes in patients with epilepsy in comparison with normal population. A short period analysis of HRV was performed for both the frequency and time domain in 43 epilepsy patients who had generalized tonic-clonic seizures (GTCS) and who were not taking any medications and also in 43 age and sex matched controls. In the time domain analysis, patients displayed higher SDNN (standard deviation of all R-R intervals), SDANN (standard deviation of mean NN intervals in 5 min recordings) and HRV triangular index than did healthy subjects (p < 0.0001). Patients tended to display higher pNN50 (number of R-R intervals differed by > 50 ms from adjacent interval divided by the total number of all R-R intervals) and RMSSD (root-mean-square of successive differences) values than did healthy subjects, but the differences were not statistically significant (p > 0.05). In the frequency domain analysis, the spectral measures of HRV showed a reduction of high frequency (HF) values (is a marker of parasympathetic activity) and an increase of low frequency (LF) values (is a measure of sympathetic activity); as a result, the ratio between low and high frequencies (LF/HF) was significantly increased (p < 0.0001, p < 0.0001 and p < 0.001, respectively). Our data suggests an increase in the sympathetic control of the heart rate in epilepsy patients who have GTCS. This increased sympathetic activity could play a key role in the development of ventricular tachyarrhythmias in patients with epilepsy and may be related to the higher incidence of sudden death in this disorder as compared to controls.

Adult↗

PubMed2005

Angiotensin-converting enzyme polymorphism in healthy young subjects: relationship to left ventricular mass and functions.

OBJECTIVES: Angiotensin-converting enzyme (ACE) is a key enzyme in the production of angiotensin II and thus may participate in the modulation of cardiac growth. The cloning of the ACE gene has made it possible to identify a deletion (D)-insertion (I) polymorphism that appears to affect the level of serum ACE activity. The aim of the study is to analyse the ACE gene I/D polymorphisms in healthy young subjects and to evaluate its relationship to left ventricular mass and functions. METHODS: 38 women and 40 men (mean age 21.1 +/- 1.7 and 21.4 +/- 1.7 years) were studied. They underwent complete echocardiographic assessment and analysis of ACE insertion (I) and deletion (D) allele frequencies in peripheral blood by polymerase chain reaction. Thickness of interventricular septum (IVS) and posterior wall (LVPW) and left ventricular mass (LVM) and LVM index (LVMI) were measured by M-mode. Left ventricular ejection fraction (LVEF) was calculated by Simpson's method. RESULTS: There was no statistically significant difference among the DD, DI and II genotypes, concerning age, body mass index, heart rate, systolic and diastolic blood pressures.The thickness of IVS (9.5 mm), LVPW (9.0 mm), LVM (204.5 g) and LVMI (105.5 g/m2) in DD genotypes were higher than both DI (8.3 mm; 8.1 mm; 168.1 g; 90.9 g/m2) and II genotypes (8.2 mm; 7.0 mm; 141.7 g; 77.8 g/m2) in men, but not in women. LVEF among the 3 genotypes were not statistically different. CONCLUSION: Our findings suggest that left ventricular hypertrophy is partially determined by genetic disposition especially in men but not in women.

Adult↗

PubMed2005

[Do left ventricular mass, diameters and long-axis systolic function differ according to angiotensin converting enzyme genotypes?].

OBJECTIVE: Angiotensin converting enzyme (ACE) is a key enzyme in angiotensin II production which causes myocardial hypertrophy and hyperplasia. In this study we aimed to investigate the relation between ACE I/D gene polymorphism and left ventricular mass (LVM), dimensions and systolic functions calculated by mitral annular motion (MAM) in young healthy male subjects. METHODS: Complete echocardiographic examination was performed in 49 male healthy subjects (mean age 22.9+/-2.1 years) consisting of 18 ACE DD, 18 ACE DI and 13 ACE II genotypes. We calculated LVM and mass index (LVMI) by M-Mode echocardiography. The systolic MAM was recorded at 4 sites (septal, lateral, anterior, and posterior) by M-mode echocardiography and the MAM-ejection fraction (EF) was calculated from above four sites. Ejection fraction was also calculated by Simpson's method. RESULTS: There was no significant difference among the three genotypes according to age, body mass index, systolic and diastolic blood pressure and heart rate. Interventricular septum (IVS) and left ventricular posterior wall (LVPW) diastolic thickness, LVM and LVMI were found significantly different among 3 ACE genotypes. Those measurements were higher in DD genotype in comparison to the DI and II genotypes. There was no significant difference among the three genotypes according to EF-MAM and EF by Simpson's method. CONCLUSION: In young healthy male subjects having ACE DD genotype, even though LVM and LVMI were within normal limits, their measurements were found to be higher than in subjects with ACE DI and II genotypes respectively. There was no difference among the three genotypes according to left ventricular systolic functions.

Adult↗

PubMed2005

Do female patients with metabolic syndrome have masked left ventricular dysfunction?

OBJECTIVE: Metabolic syndrome (MS) is a condition, which is recognized as raising the risk of cardiovascular disease. The aim of our study is to estimate the left ventricular functions by atrioventricular plane displacement (AVPD), myocardial performance index (MPI) and conventional methods in patients with MS who were diagnosed according to NCEP (ATP III) criteria. METHODS: Fifty-three female patients with MS (mean age 53.1+/-6.9 years) and 30 healthy female subjects (mean age 52.8+/-6.3 years, p>0.05) underwent complete echocardiographic assessment. All of the subjects had no heart and pulmonary diseases. The systolic mitral AVPD was recorded at 4 sites (septal, lateral, anterior, and posterior) by M-mode echocardiography and left ventricle ejection fraction (LVEF) was calculated from the AVPD-mean (EF-AVPD). The LVEF was also established by biplane Simpson's (EF-2D) and Teichholz's methods (EF-T). Left ventricular MPI was calculated as (isovolumic contraction time + isovolumic relaxation time) / aortic ejection time by Doppler echocardiography. RESULTS: Patients with MS showed mild left ventricular diastolic dysfunction (DD) in comparison to healthy subjects. The EF-2D and EF-T in patients with MS and healthy subjects were not different significantly and were within normal limits. Patients with MS showed LV global dysfunctions compared to healthy subjects (MPI: 0.56+/-0.12 and 0.46+/-0.11 respectively, p<0.01). Both the septal, anterior, lateral and posterior part of the atrioventricular plane values and also AVPD-mean during systole were statistically lower in patients with MS (12.85+/-1.76 mm) as compared with controls (14.65+/-2.19 mm, p<0.05). The EF-AVPD in patients with MS was statistically lower (65.58+/-11.95%) as compared with healthy subjects (74.45+/-11.07%, p<0.01). CONCLUSION: Female patients with MS had both left ventricular DD and a global dysfunction with an increased MPI. The EF-2D and EF-T were not different significantly between patients and controls, but patients with MS had a relatively reduced EF-AVPD. The AVPD method may indicate a systolic dysfunction with a relatively lower AVPD-mean and relatively lower EF-AVPD. The presence of global dysfunction in patients with MS may lead to heart failure.

Case-Control Studies↗

PubMed2004

Lp(a) lipoprotein and lipids in patients with rheumatoid arthritis: serum levels and relationship to inflammation.

OBJECTIVES: Changes in lipid profiles, Lp(a) lipoprotein, and acute phase reactants are associated with early atherosclerosis in rheumatoid arthritis (RA). The associations of Lp(a) levels with atherosclerotic disorders, diabetes, RA, and renal diseases suggest that Lp(a) might be involved in autoimmune reactions. METHODS: Eighty-seven women with RA diagnosed according to American Rheumatism Association criteria (mean age 45.4+/-9.4 years) were recruited and 50 healthy women (mean age 44+/-10.7 years) included as a control group. Serum Lp(a), total cholesterol (TC), triglyceride (TG), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), and C-reactive protein levels were analyzed. RESULTS: In the RA and C groups, serum Lp(a) levels were 39.2+/-20.6 mg/dl and 14.8+/-9.7 mg/dl, respectively (P<0.001). The TC levels were 188.4+/-41.8 mg/dl and 185.3+/-19.3 mg/dl (P>0.05), TG levels were 124.5+/-50.1 mg/dl and 94.6+/-24.9 mg/dl (P<0.01), HDL-C levels were 40.0+/-7.4 mg/dl and 52.8+/-4.8 mg/dl (P<0.01), and LDL-C levels were 123.4+/-24.6 mg/dl and 113.3+/-21.1 mg/dl (P>0.05). While serum CRP levels showed a positive correlation with Lp(a), they correlated negatively with HDL-C levels (r=0.83 and P<0.0001, r=-0.49 and P<0.0001, respectively). It was meaningful that Lp(a) correlated negatively with serum HDL-C level (r=-0.36, P<0.001). CONCLUSIONS: It is suggested that higher serum Lp(a), lower HDL-C, higher TG level, and a high ratio of TC/HDL-C might show high risk of atherosclerosis. Inflammation in RA may cause changes in HDL-C and Lp(a) metabolisms.

Acute-Phase Proteins↗

PubMed2004

Bilateral diagonal earlobe crease and coronary artery disease: a significant association.

BACKGROUND: The association between the presence of diagonal earlobe crease (ELC) and coronary artery disease (CAD) still remains controversial. OBJECTIVE: The aim of this study was to evaluate the association between bilateral ELC and CAD. METHODS: 415 patients were examined for the presence or absence of bilateral ELC, angiographic evidence of CAD and coronary risk factors. The patients were divided into 2 groups according to angiographic evidence of CAD. RESULTS: Bilateral ELC was significantly and positively correlated with CAD, hypertension, age, male gender, cigarette smoking and family history of CAD. The ELC was an independent variable for CAD. The observed sensitivity, specificity, positive predictive value and negative predictive value of the bilateral ELC for the diagnosis of CAD were in the following order: 51.3, 84.8, 89.4 and 41.2%. CONCLUSION: The presence of bilateral ELC was significantly associated with CAD and coronary risk factors. The bilateral ELC was an important dermatological indicator of CAD, and it might be a useful diagnostic tool in the clinical examination of patients.

Adult↗

PubMed2004

Assessment of systolic function by atrioventricular plane displacement in patients with diastolic dysfunction.

OBJECTIVES: Early recognition and appropriate therapy of diastolic dysfunction (DD) is advisable to prevent further progression to diastolic or systolic heart failure and death. The mitral atrioventricular plane displacement (AVPD) method has been shown to be a reliable and simple technique to study left ventricular systolic function in patients, because the mitral annulus can be visualized in almost all patients even if the endocardial borders are difficult to trace. The aim of our study is to estimate the left ventricular ejection fraction by AVPD method (EFAVPD), in addition to Teicholz's short axis method (EF-T) and Simpson's biplane method (EF-2D) in patients with DD. MATERIAL AND METHODS: One hundred and two subjects were submitted to complete echocardiographic assessment, and DD was shown in 62 patients. The systolic mitral AVPD was recorded at 4 sites (septal, lateral, anterior, and posterior) using M-mode and left ventricular ejection fraction was calculated from the AVPD-mean in 62 patients with DD (mean age 55.67 +/- 5.65, 24 men and 38 women) and in 40 age-matched control subjects (mean age 54.07 +/- 6.96, 15 men and 25 women). There were no statistically significant group differences related to age, gender, heart rate or body mass index. However, in the patients with DD, presence of hypertension and/or diabetes mellitus was significantly higher than control subjects. RESULTS: The systolic functions, as assessed by conventional measures in patients with DD and healthy subjects were not stastically different, and were within normal limits. The septal, anterior, lateral and posterior part of the atrioventricular plane values and AVPD-mean during systole were statistically lower in the DD group (12.35 +/- 1.42 mm) compared with controls (15.32 +/- 1.38 mm) (p < 0.001). EFAVPD in patients with DD was statistically lower (62.97 +/- 7.85%) than healthy subjects (79.30 +/- 7.60%) (p < 0.001). Significant positive correlations between EFAVPD and EF-2D (r = 0.325, p < 0.01) and EF-T (r = 0.355, p < 0.01) and FS (r = 0.314, p < 0.01) were found. EFAVPD correlated only with velocity of mitral flow propagation (VPR) in diastolic function parameters (r = 0.374, p < 0.01). CONCLUSIONS: The AVPD method may indicate a systolic dysfunction with a relatively lower AVPD-mean and relatively lower EFAVPD in the DD group compared with controls. This indicated the presence of a statistically significant and mildly reduced left ventricular systolic function by the AVPD method in patients with DD. It might be suggested that DD might be combined with systolic dysfunction. However, isolated diastolic dysfunction is uncommon. The mitral AVPD is reproducible, widely applicable and a simple non-invasive method for the estimation of left ventricular systolic function in patients with DD.

Blood Flow Velocity↗

PubMed2003

Heart rate variability in patients with rheumatoid arthritis.

Heart rate variability (HRV) is a useful tool for the detection of sympathetic-parasympathetic balance in the autonomic nervous system. Autonomic nervous system involvement in patients with rheumatoid arthritis (RA) has rarely been studied and has shown conflicting results. Our purpose was to determine if HRV showed changes in patients with RA in comparison with the normal population. Short-term analysis of HRV was performed for time-domain frequency in 42 patients with RA and 44 matched controls. In this analysis, patients displayed lower standard deviation of the mean than healthy subjects ( P<0.0001). Patients tended to display higher pNN50 and root-mean-square of successive difference values than did healthy subjects, but these differences were not statistically significant (P >0.05). In frequency domain analysis, the spectral measures of HRV showed reduced high-frequency (HF) values and an higher low-frequency (LF) values; as a result, the ratio between low and high frequencies (LF/HF), representative of sympathovagal modulation, was significantly increased (P=0.001, P=0.012, and P=0.003, respectively). Our data suggest an increase in sympathetic control of the heart rate in patients with RA. This increased sympathetic activity could play a key role in the development of ventricular tachyarrhythmias in RA and may be related to the higher incidence of sudden death in this disorder.

Arrhythmias, Cardiac↗

PubMed2003

[Mitral valve prolapse syndrome: orthostatic hypotension and physiopathology of its clinical symptomathologies].

Although several investigations on mitral valve prolapse syndrome (MVPS) have been performed, clinical symptoms of this syndrome are not yet clarified. Atypical chest pain, palpitations, fatigue, dyspnea and anxiety are the most frequent symptoms associated with this syndrome. However, dizziness and syncope may be serious symptoms in MVPS. Dizziness and syncope are related to cardiac arrhythmias and are proposed to distinguish types, frequency of arrhythmias and relation to the symptoms. Orthostatic hypotension and tachycardia rarely occur in MVPS. The physiopathological mechanisms of these symptoms are not known clearly, but multifactorial causes are thought to be responsible including autonomic dysfunction, hyperadrenergic state, abnormalities in regulation of baroreceptors, parasympathetic derangements, decrease of intravascular volume, abnormal renin-aldosterone response to depletion of intravascular volume and abnormal release of atrial natriuretic factor.

Dizziness↗

PubMed2003

[Ischemic preconditioning].

It has been shown that repeated brief coronary occlusions increase myocardial resistance towards prolonged episodes of ischemia. This phenomenon, which renders the heart more tolerant to ischemia with subsequent limitation of infarct size, has been termed ischemic preconditioning. Ischemic preconditioning also protects the heart against postinfarction left ventricular dysfunction and ventricular arrhythmias. Ischemia induced activation of adenosine receptors, and opening of ATP-sensitive potassium channels and stress protein synthesis are thought to be the potential mechanisms of this phenomenon. The exploration of the exact mechanisms of ischemic preconditioning might improve the treatment strategies for acute myocardial infarction in the future.

Humans↗