Ahmet Altinbas

Mobile phone-induced myocardial oxidative stress: protection by a novel antioxidant agent caffeic acid phenethyl ester.

Electromagnetic radiation (EMR) or radiofrequency fields of cellular mobile phones may affect biological systems by increasing free radicals, which appear mainly to enhance lipid peroxidation, and by changing the antioxidant defense systems of human tissues, thus leading to oxidative stress. Mobile phones are used in close proximity to the heart, therefore 900 MHz EMR emitting mobile phones may be absorbed by the heart. Caffeic acid phenethyl ester (CAPE), one of the major components of honeybee propolis, was recently found to be a potent free radical scavenger and antioxidant, and is used in folk medicine. The aim of this study was to examine 900 MHz mobile phone-induced oxidative stress that promotes production of reactive oxygen species (ROS) and the role of CAPE on myocardial tissue against possible oxidative damage in rats. Thirty rats were used in the study. Animals were randomly grouped as follows: sham-operated control group (N: 10) and experimental groups: (a) group II: 900 MHz EMR exposed group (N: 10); and (b) group III: 900 MHz EMR exposed+CAPE-treated group (N: 10). A 900 MHz EMR radiation was applied to groups II and III 30 min/day, for 10 days using an experimental exposure device. Malondialdehyde (MDA, an index of lipid peroxidation), and nitric oxide (NO, a marker of oxidative stress) were used as markers of oxidative stress-induced heart impairment. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status. In the EMR exposed group, while tissue MDA and NO levels increased, SOD, CAT and GSH-Px activities were reduced. CAPE treatment in group III reversed these effects. In this study, the increased levels of MDA and NO and the decreased levels of myocardial SOD, CAT and GSH-Px activities demonstrate the role of oxidative mechanisms in 900 MHz mobile phone-induced heart tissue damage, and CAPE, via its free radical scavenging and antioxidant properties, ameliorates oxidative heart injury. These results show that CAPE exhibits a protective effect on mobile phone-induced and free radical mediated oxidative heart impairment in rats.

Statin Use before By-Pass Surgery Decreases the Incidence and Shortens the Duration of Postoperative Atrial Fibrillation

Backround: The aim of the present observational study is to search the incidence of postoperative atrial fibrillation (AF) in patients with or without preoperative statin treatment. Methods andResults: The population consisted of 362 consecutive patients (267 on and 95 not on statin). Diabetes mellitus was more frequent in statin group (p = 0.03). Other demographic and procedural variables were similar in the both groups (All p > 0.05). Postoperative AF was less frequent and its duration was shorter in statin group compared to non-statin group (p = 0.03 and 0.0001, respectively). The Kaplan-Meier analysis showed the protective effect of statins against the risk of developing AF (p = 0.01). Conclusion: Statin treatment before the by-pass surgery decreases the incidence and shortens the duration of postoperative AF.

A comparison of P-wave duration and dispersion in patients with short-term and long-term atrial fibrillation

This study compared P-wave duration and dispersion (PD) in patients with short-term (<or=48 hours) and long-term (>48 hours) atrial fibrillation (AF) after cardioversion. We studied 96 consecutive patients with short-term (group A; n:51, age: 61 +/- 11 years) and long-term AF (group B; n:45, age: 64 +/- 10 years). P-wave measurements were calculated from 12-lead electrocardiogram. There was no difference related to clinical characteristics. Left atrial dimension was significantly higher in group B (P =.003). P maximum (124 +/- 12 vs. 113 +/- 11 ms, P =.001) and PD (57 +/- 8 vs. 49 +/- 9 ms, P =.001) were also significantly longer in group B compared with group A, but P minimum did not. In univariate analysis, PD were related to AF duration (P =.002) and left atrial size (P =.02). This relation remained in multivariate analysis (P =.01, P =.02, respectively). P maximum >112 ms and PD >47 ms had accuracy values of 74% and 83% respectively for separating group B. Our results suggest that P wave duration and dispersion is prolonged in patients with long-term AF compared to short-term AF.

Mean platelet volume is associated with insulin resistance in non-obese, non-diabetic patients with coronary artery disease

BACKGROUND AND PURPOSE Mean platelet volume (MPV), an indicator of platelet activation, has been shown to be elevated in patients with coronary artery disease (CAD) in some studies. Insulin resistance contributes to increased platelet activation and it is one of the risk factors for CAD. The aim of this study was to assess the relationship between insulin resistance and MPV in non-obese, non-diabetic patients with CAD. METHODS AND SUBJECTS Seventy-seven non-obese, non-diabetic CAD patients were divided into two groups, insulin resistant and insulin sensitive according to the homeostasis model assessment insulin resistance index (HOMA-IR). The insulin-resistant group was composed of 45 patients (30 males/15 females; mean age 59.8±11.1 years). The insulin-sensitive group was composed of 32 patients (17 males/15 females; mean age 58.9±12.2 years). RESULTS Insulin and HOMA-IR values were significantly higher in insulin-resistant CAD patients than in insulin-sensitive CAD patients. The MPV values were significantly higher in insulin-resistant CAD patients than in insulin-sensitive CAD patients (8.6±1.0 fl vs. 8.0±0.7 fl; respectively, p=0.01). The MPV was poorly correlated with HOMA-IR (r=0.30, p=0.054) and insulin (r=0.22, p=0.053). CONCLUSIONS We have shown that MPV was significantly elevated in insulin-resistant non-obese, non-diabetic CAD patients when compared to insulin-sensitive non-obese, non-diabetic CAD patients.

Elevated carbohydrate antigen 125 levels in hypertrophic cardiomyopathy patients with heart failure

Carbohydrate antigen 125 (CA 125), known as a tumor marker for ovarian cancer, has been reported to increase and relate to severity in heart failure patients with systolic dysfunction. Hypertrophic cardiomyopathy (HCM) has a wide clinical spectrum that often includes heart failure symptoms. The aim of this study was to evaluate the role of CA 125 in HCM patients, its relation to severity of symptoms, and degree of diastolic dysfunction. CA 125 blood levels were determined in 32 HCM patients (21 male; age 51.3 ± 18.4 years) and in 30 healthy volunteers (19 male; age 49.6 ± 16.1 years). Echocardiographic examinations were performed in all patients. The results were grouped according to clinical status (New York Heart Association class) of the patients. The mean serum level of CA 125 was 14.6 ± 23.8 U/ml in the study group and 7.6 ± 4.8 U/ml in the control group. There was no significant difference between the groups (P = 0.12). CA 125 levels increased as the New York Heart Association functional class increased (class I/II: 6.2 ± 2.4 U/ml; class III: 30.6 ± 36.4 U/ml; P < 0.001). The mean CA 125 level in functional class III patients (30.6 ± 36.4 U/ml) was significantly higher than that of the control group (7.6 ± 4.8 U/ml) (P < 0.001) and the functional class I/II group (6.2 ± 2.4 U/ml) (P < 0.001). There was a significant difference over all three diastolic dysfunction groups with respect to CA 125 levels (4.9 ± 1.3 U/ml in impaired relaxation group, 11.8 ± 6.9 U/ml in pseudonormal group, and 52.6 ± 45.6 U/ml in restrictive filling group; P < 0.0001). Serum CA 125 is related to the clinical severity of HCM. Whether CA 125 has a specific biological role in HCM requires further investigation.

Efficacy of propafenone for maintaining sinus rhythm in patients with recent onset or persistent atrial fibrillation after conversion: a randomized, placebo-controlled study.

Objective — The aim of this study was to investigate the efficacy and safety of propafenone in the prevention of atrial fibrillation (AF) relapse after restoration of sinus rhythm. Methods — This study consisted of 110 consecutive patients with recent onset and persistent AF. After restoration of sinus rhythm, patients were randomized to propafenone (n: 58, age: 60 ± 12 years) or placebo (n: 52, age: 62 ± 10 years).There were 11 withdrawals (7 in the propafenone and 4 in the placebo group) during follow-up. Follow-up evalutations were conducted at the first, 3rd and then at an interval of three months during 15 months. The clinical characteristics in both groups were comparable.The AF relapse was analysed by the Kaplan-Meier method. Results — At 15-month follow-up, AF relapsed in 20 (39%) and 31 (65%) patients in the propafenone and placebo groups, respectively (p = 0.015). In subgroup analysis, AF recurrence was significantly lower in the propafenone group than in the placebo group only in the recent onset AF patients with spontaneous conversion (21% vs. 61%, p = 0.01). However, the AF relapse rates were similar in patients with persistent AF and with recent AF who converted to sinus rhythm pharmacologically or electrically in the propafenone and placebo groups. Four patients on propafenone and one on placebo had adverse effects necessitating discontinuation of the drug (p = 0.36). Conclusion — At 15 months, propafenone seems to be superior to placebo for maintaining sinus rhythm in patients with recent onset or peristent AF. This superiority originates mainly from patients with recent onset AF in whom sinus rhythm occurred spontaneously. Its adverse effects are similar to placebo. (Acta Cardiol 2004; 59(3): 255-261)

The association between previous statin use and development of atrial fibrillation in patients presenting with acute coronary syndrome

AIMS To examine the association between statin use and the development of atrial fibrillation (AF) in patients presenting with acute coronary syndrome (ACS). METHODS From a total of 1000 patients presenting with ACS 241 were on and 759 were not on statin. An AF episode was accepted as endpoint. RESULTS The incidence of AF was less frequent in statin group compared to non-statin group (5% vs 10%, respectively, p=0.01). Independent predictors of AF were left atrial diameter, use of statin, age, hypertension, previous AF and use of angiotensin converting enzyme inhibitors or angiotensin receptor blockers. CONCLUSIONS In ACS patients, statin treatment was associated with lower incidence of AF.

Use of tissue Doppler echocardiography in early detection of left ventricular systolic dysfunction in patients with mitral regurgitation

Objective: Left ventricular ejection fraction (EF) and left ventricular (LV) end-systolic diameter measurements are the most widely accepted and utilized methods to demonstrate LV dysfunction in patients with mitral regurgitation (MR). However, these parameters still have many drawbacks in predicting early LV dysfunction. This study investigates the clinical usefulness of tissue Doppler echocardiography technique in detecting early disturbance of myocardial contractility in asymptomatic patients with chronic, severe MR and normal LV ejection fraction values. Methods and Results: Regional systolic peak velocities of mitral annular motion during the ejection phase of systole (SW2) were obtained at the mitral annuli of the ventricular septal, lateral, anteroseptal, posterior, anterior and inferior wall sites in the long axis in 31 asymptomatic patients with severe MR (with a regurgitant volume of more than 50 ml) and with EFs more than 60%. The patients were grouped according to their dP/dt values (more or less than 1300 mm Hg/s) estimated non-invasively by using continuous Doppler wave of MR SW2 measurements of Group I were higher than Group II in all of the analyzed segments. The difference was statistically significant for all of the segments. SW2 values of the whole study group was moderately correlated with dP/dt measurements in all of the analyzed segments other than the interventricular septum. Conclusion: SW2 measurements in the long axis, which are considered to be relatively independent from afterload conditions may be helpful in early detection (while EF is still in normal range) of LV systolic dysfunction during the follow-up of patients with chronic MR.

A giant aneurysm of the circumflex coronary artery with fistulous connection to the coronary sinus: a case report.

Non-atherosclerotic coronary artery aneurysms are rare and most of them remain asymptomatic. We report a case who has a giant circumflex coronary artery aneurysm with fistulisation into the coronary sinus. The patient presents with dyspnea and palpitation due to atrial fibrillation with rapid ventricular response. The diagnostic contributions of echocardiography, coronary angiography are discussed. The hemodynamic effects of this anomaly are reviewed.

Recurrent acute stent thrombosis associated with protein C and S deficiencies

Protein C and protein S deficiencies may uncommonly be responsible for coronary arterial thrombosis. We report a young woman with recurrent acute stent thrombosis due to the deficiency of protein C and S. After coronary stenting, stent thrombosis occurred two times despite aggressive antiplatelet therapy, including aspirin, clopidogrel and glycoprotein IIb/IIIa inhibitor. This report suggests that the deficiency of protein C and S should be born in mind in a young patient with recurrent thrombotic events, and that anticoagulants in addition to antiplatelet agents considered in the presence of their deficiency.