Sencan Ozme | Hacettepe University (original) (raw)

Papers by Sencan Ozme

Research paper thumbnail of Dysrhythmia as a cause of syncope in children without neurological or cardiac morphological abnormalities

Pediatrics International, 2002

Background : Arrhythmias are among the malignant causes of syncope. This study has been undertake... more Background : Arrhythmias are among the malignant causes of syncope. This study has been undertaken to determine the relative incidence and significance of dysrhythmia in the pathogenesis of syncope among patients referred to a pediatric cardiology unit. Methods : Between March 1997 and March 1999, 105 consecutive patients (59 female, 46 male) aged 11.5 ± 3.6 years without neurologic or cardiac morphologic causes were evaluated for at least one episode of syncope. A pediatric cardiologist and a pediatric neurologist evaluated all the patients. Routine chest X‐ray, 12‐lead electrocardiogram (ECG), electroencephalography (EEG), 24‐h Holter monitoring and echocardio­graphy were carried out. When deemed necessary, further tests were undertaken for the cases of syncope which were unexplained by routine tests. Results : The cause of syncope was identified as vasovagal in 25.7% (n = 27) and related to dysrhythmia in 30.5% (n = 32). The cause was migraine‐associated syncope in two children, ...

Research paper thumbnail of Double-chambered right ventricle: experience with 52 cases

International Journal of Cardiology, 1995

The presence of anomalous muscle bundles may produce a pressure gradient between the inflow and o... more The presence of anomalous muscle bundles may produce a pressure gradient between the inflow and outflow portions of the right ventricle, thus resulting in double-chambered right ventricle bearing troublesome clinically in its diagnosis. The aim of the present study was to review the diagnostic criteria. Fifty-two patients with a double-chambered right ventricle were seen during an &year period. They ranged in age at the catheterization from 4 months to 17 years (mean 7.5 f 4.4 years). Diagnosis was confirmed in 51 patients at cardiac catheterization and in other one on operation. The majority of the patients had associated cardiac anomalies: there were 33 ventricular septal defect (63%), 21 pulmonary valve stenosis (40%), nine atria1 septal defect (17%), and four double-outlet right ventricle. The electrocardiograms revealed upright T waves alone in right precordial leads suggesting right ventricular hypertrophy in 33% of the patients. At cardiac catheterization, there was a pressure gradient of 20-160 mmHg between the right ventricular inflow and outflow portions. Forty patients have had surgery and four have undergone balloon pulmonary valvuloplasty. Surgical treatment was planned for two patients and other six had no indication for treatment.

Research paper thumbnail of Çocukluk Çağı Taşikardilerinin Tanı ve Tedavisinde Adenozinin Yeri

Turkiye Klinikleri Journal of Cardiology, 1994

Research paper thumbnail of Surgical treatment in tetralogy of Fallot diagnosed by echocardiography

International Journal of Cardiology, 1992

Surgical treatment in tetralogy of Fallot diagnosed by echocardiography. Int J Cardiol 1992;37:32... more Surgical treatment in tetralogy of Fallot diagnosed by echocardiography. Int J Cardiol 1992;37:329-335.

Research paper thumbnail of Active-fixation, steroid-eluting ventricular leads: the medium-term results in children

Anadolu kardiyoloji dergisi : AKD = the Anatolian journal of cardiology, 2005

Low threshold characteristics and mechanical stability are important features of an ideal pacing ... more Low threshold characteristics and mechanical stability are important features of an ideal pacing lead, especially for children. We report our experience and medium-term results with a steroid-eluting, active-fixation ventricular lead in children. Telectronics Accufix II DEC model 033-212 ventricular leads were implanted in 21 patients. Eighteen patients (11 male / 7 female; 10.6+/-4.0 years), who were followed for a mean period of 6.47 +/-1.13 years, were included in the study. Pacemaker mode was DDDR in three patients, and VVIR in the remaining 15 patients. Mean threshold value was 0.5 volts at implant, which increased to 0.7 volts in the first month (p>0.05). It remained stable (0.62-0.78 V) until 5.5 years (p>0.05), increased significantly at 5.5 years (0.99+/-0.63 V at 5.5 years, p<0.05) and remained significantly high after this time (p<0.05). Pacing lead impedance did not differ significantly throughout the study (p>0.05). Thirteen pulse generators reached end-o...

Research paper thumbnail of Dual chamber cardiac pacing in children: Single chamber pacing dual chamber sensing cardiac pacemaker or dual chamber pacing and sensing cardiac pacemaker?

Pediatrics International, 2002

Background : Dual chamber pacemakers (single chamber pacing dual chamber sensing cardiac pacemake... more Background : Dual chamber pacemakers (single chamber pacing dual chamber sensing cardiac pacemaker (VDD) and dual chamber pacing and sensing cardiac pacemaker (DDD)) are being used frequently in children and adolescents. The aim of this study was to verify the safety and performance of the VDD and DDD pacing systems, and to evaluate the differences between two pacing modes with regard to atrial sensing and tracking functions. Methods : In this study, we evaluated 14 patients with VDD pacing and 15 patients with DDD pacing between 1994 and 2000. In the patient group with VDD pacing, all had congenital or acquired atrioventricular (AV) block. In the patient group with DDD pacing, 11 had congenital or acquired AV block, three had sinus node dysfunction with AV conduction disturbance and one had idiopathic hypertrophic subaortic stenosis. Twentyeight devices were implanted in the subpectoral area using the transvenous route. After implantation the atrial tracking capabilities of the pacing systems were analyzed by telemetry, Holter monitoring, and treadmill exercise testing. Results : The mean age of patients in the VDD pacing group was younger. The percentage of congenital heart disease was higher in the DDD pacing group. There was no significant difference regarding fluoroscopy time during implantation and follow-up time between the two groups. During implantation, in the VDD pacing group the mean sensed atrial signal was 3.1 ± 1.3 mV and this decreased to 1.37 ± 0.68 mV ( P < 0.05) during follow-up. This pattern was also observed in DDD group (3 ± 2 mV vs 1.9 ± 1.5 mV, P < 0.05). Although the P wave measurement at implantation did not differ between the two groups, it was significantly higher in the DDD pacing group at the last control. Three patients with VDD pacing were reprogrammed to VVI or single chamber pacing and sensing, rate adaptive cardiac pacemaker because of complete loss of AV synchrony. There was no atrial sensing problem in the DDD pacing group. During the follow-up, one patient with VDD pacing developed diaphragmatic stimulation and required lead revision. In one patient with DDD pacing, venous thrombosis occurred in the right subclavian vein and was treated with thrombolytic therapy. During treadmill exercise testing, in one patient with VDD and one patient with DDD pacing temporary failure of atrial sensing occurred. At 24 h Holter monitoring, intermittent loss of atrial sensing was documented in two patients with VDD pacing. Conclusions : Dual chamber pacing in children with DDD or VDD pacemakers is a suitable method for bradycardia treatment. Atrial sensing problems may occur in VDD pacemakers. Therefore, DDD pacing mode should be preferred whenever suitable for the patient to maintain the AV synchrony.

Research paper thumbnail of Evaluation by exercise testing of children with mild and moderate valvular aortic stenosis

Pediatrics International, 2000

The aim of the present paper was to determine the factors related to sudden death in aortic steno... more The aim of the present paper was to determine the factors related to sudden death in aortic stenosis. The factors related to sudden death were investigated in 40 asymptomatic children with mild and moderate aortic stenosis by treadmill testing. The QT interval of aortic stenosis cases were significantly longer than those of healthy children with increasing heart rates during exercise. A longer QT interval of aortic stenosis cases compared to normal children during exercise is the first sign of myocardial ischemia and leads to fatal ventricular arrhythmias and sudden death. For this reason we recommend that exercise testing should be performed frequently in aortic stenosis patients and that close follow up is necessary for patients with long QT segments that can be a marker for severe arrhythmias.

Research paper thumbnail of Dual Sensor Pacemakers in Children: What is the Choice of Sensor Blending?

Pacing and Clinical Electrophysiology, 1997

Dual sensor pacemakers were developed to obtain more appropriate responses to activity. We evalua... more Dual sensor pacemakers were developed to obtain more appropriate responses to activity. We evaluated ten children with dual sensor pacemakers in different sensor blending circumstances using exercise testing to assess which ratio was optimal. Ten patients with several bradydysrhythmias (ages 6-16 years; mean 10.1 years) were included in the study. Eight patients had VVIR pacemakers (Vitatron Topaz), models and two patients had VDD pacemakers implanted via the transvenous route. All patients were in a paced rhythm (98.5% pacing). Accurate T wave sensing ranged from 81%-100%; mean 92%, median 95%. Voluntary exercise testing with a CAEP protocol was performed using a treadmill with the pacemaker in VVIR mode. Medium activity threshold with three sensor blending ratios (QT = ACT, QT &gt; ACT, and QT &lt; ACT) were done in all patients. The mean duration of exercise was not statistically different among the three sensor blending ratios. After 90 seconds of exercise, the mean pacing rate had increased by 12%, 3%, and 5%, respectively, in the three groups. At maximal exercise, the increases were 45%, 42%, and 54%. Mean HRs during exercise in each of the three ratios were not significantly different, although we found a statistically significant increase in HR during the first two stages of rest period in the QT = ACT sensor blending ratio compared to the QT &gt; ACT ratio. No difference was observed after the second stage. (1) there is no difference between the QT = ACT, QT &lt; ACT, and QT &gt; ACT sensor blending ratios; and (2) each child has to be evaluated by exercise testing to program a correct sensor blending ratio.

Research paper thumbnail of Sotalol in treatment of pediatric cardiac arrhythmias

Pediatrics International, 2001

Research paper thumbnail of Dysrhythmia as a cause of syncope in children without neurological or cardiac morphological abnormalities

Pediatrics International, 2002

Background : Arrhythmias are among the malignant causes of syncope. This study has been undertake... more Background : Arrhythmias are among the malignant causes of syncope. This study has been undertaken to determine the relative incidence and significance of dysrhythmia in the pathogenesis of syncope among patients referred to a pediatric cardiology unit. Methods : Between March 1997 and March 1999, 105 consecutive patients (59 female, 46 male) aged 11.5 ± 3.6 years without neurologic or cardiac morphologic causes were evaluated for at least one episode of syncope. A pediatric cardiologist and a pediatric neurologist evaluated all the patients. Routine chest X-ray, 12-lead electrocardiogram (ECG), electroencephalography (EEG), 24-h Holter monitoring and echocardiography were carried out. When deemed necessary, further tests were undertaken for the cases of syncope which were unexplained by routine tests. Results : The cause of syncope was identified as vasovagal in 25.7% ( n = 27) and related to dysrhythmia in 30.5% ( n = 32). The cause was migraine-associated syncope in two children, psychogenic syncope in three children and orthostatic hypotension in one patient. The cause was unknown in 36.2% ( n = 38). Conclusion : We conclude that dysrhythmia is a significant and frequent cause in children referred to pediatric cardiology units. The combination of ECG, Holter monitoring, electrophysiologic study, transtelephonic ECG and head-up tilt test can identify the underlying cause of syncope in as many as 58% of these patients that present with syncope.

Research paper thumbnail of Effectiveness and safety of intravenous amiodarone in drug-resistant tachyarrhythmias of children

Pediatrics International, 1998

B a c k g r o d Experience with pediatric use of intravenous amiodarone is limited. In this study... more B a c k g r o d Experience with pediatric use of intravenous amiodarone is limited. In this study, our experiences with intravenous amiodarone in children with acute life-threatening or chronic tachyarrhythmias are reviewed.

Research paper thumbnail of Body mass index and lipid levels in children from Ankara, Turkey versus Bogalusa, Louisiana

Preventive Medicine, 2005

Background: Turkish Heart Study demonstrated that low high density lipoprotein cholesterol levels... more Background: Turkish Heart Study demonstrated that low high density lipoprotein cholesterol levels are prevalent among Turkish adults. Methods: We compared body mass index and lipid levels of Turkish children (n = 1525, ages 10 -17) with the bi-racial community of Bogalusa Heart Study.

Research paper thumbnail of Facioscapulohumeral syndrome with cardiomyopathy

Postgraduate Medical Journal, 1990

Research paper thumbnail of Parameters of iron deficiency in children with cyanotic congenital heart disease

Pediatric Cardiology, 1996

A group of 67 children with cyanotic congenital heart disease (CCHD) were studied, and 35 were gi... more A group of 67 children with cyanotic congenital heart disease (CCHD) were studied, and 35 were given iron treatment according to a regimen that gives iron to patients with a hematocrit (Hct) below 60%. The patients were categorized as iron-deficient and ironsufficient according to their transferrin saturation and ferritin values. The pretreatment hemoglobin (Hb) and Hct values of the groups were similar. The mean Hct was nearly three times as much as the mean Hb in the ironsufficient group and more than three times as much as the Hb in the iron-deficient group. Excessive erythrocytosis in the iron-deficient group was impressive. Mean corpuscular volume (MCV) values were below 72.7 fl in all of the iron-deficient patients. After treatment the Hb, Hct, transferrin saturation, and ferritin increased significantly in both groups, with the increments greater in the iron-deficient group. Increments in the erythrocyte (RBC) count were significant in the iron-sufficient group but insignificant in the iron-deficient one. Increments of MCV in the iron-deficient group were significant but insignificant in the iron-sufficient group. Our study demonstrated that prediction of Hb, RBC count, and MCV, measurements of which are easy and inexpensive and require little blood, can suffice for the diagnosis of iron deficiency in patients with CCHD without altering systemic perfusion.

Research paper thumbnail of Head-up tilt test: A highly sensitive, specific test for children with unexplained syncope

Pediatric Cardiology, 1996

Unexplained syncope may cause diagnostic and therapeutic problems in children. The head-up tilt t... more Unexplained syncope may cause diagnostic and therapeutic problems in children. The head-up tilt test has been shown to be a useful tool for investigating unexplained syncope, especially for diagnosis of neurally mediated syncope. In this study 20 patients aged 9-18 years (12.0 ± 2.5 years) with syncope of unknown origin and 10 healthy age-matched children were evaluated by head-up tilt to 60°for 25 minutes. The test was considered positive if syncope or presyncope developed in association with hypotension, bradycardia, or both. If tilting alone did not induce symptoms (syncope or presyncope), isoproterenol infusion was administered with increasing doses (0.02-0.08 g/kg per minute). During the tilt test, symptoms were elicited in 15 (75%) of the patients with unexplained syncope but in only one (10%) of the control group (p < 0.001). The sensitivity of the test was 75% and its specificity 90%. Three patterns of response to upright tilt were observed in symptomatic patients: vasodepressor pattern with an abrupt fall in blood pressure in 67%; cardioinhibitory pattern with profound bradycardia in 6%; and mixed pattern in 27%. In patients with positive head-up tilt, there were sudden decreases in systolic blood pressure (from 130 ± 15 to 61 ± 33 mmHg) and in mean heart rate (from 147 ± 26 to 90 ± 38 beats per minute) (p < 0.001) during symptoms. Treatments with atenolol 25 mg/day has shown complete suppression of syncope in positive responders during a mean follow-up period of 18 ± 6 months. The head-up tilt test is a noninvasive, sensitive, specific diagnostic tool for evaluating children with unexplained syncope.

Research paper thumbnail of Influence of D-Net (EUROPEAN GSM-Standard) Cellular Telephones on Implanted Pacemakers in Children

Pacing and Clinical Electrophysiology, 2002

Research paper thumbnail of Comparison of Normal Sinus Rhythm and Pacing Rate in Children with Minute Ventilation Single Chamber Rate Adaptive Permanent Pacemakers

Pacing and Clinical Electrophysiology, 1998

A., ET AL.: Comparison of Normal Sinus Rhythm and Pacing Rate in Children with Minute Ventilation... more A., ET AL.: Comparison of Normal Sinus Rhythm and Pacing Rate in Children with Minute Ventilation Single Chamher Rate Adaptive Permanent Pacemakers. Bate adaptive pacemakers are used to achieve a better cardiac performance during exercise by increasing the heart rate and cardiac output. The ideal rate adaptive sensor should be able to mimic sinus node modulation under various degrees of exercise and other metabolic needs. Minute ventilation sensing has proven to be one of the most accurate sensor systems. In this study, alterations in sinus rhythm and pacing rates during daily life conditions in 11 children (median age 11 years, range 6-14 years) with minute ventilation single chamber pacemakers were investigated. Correlation of sinus rhyihm with pacing rates was assessed. ECG records were obtained from 24-hour Holter monitoring. Average rates of five consecutive P waves and pace waves were determined every half hour. The average of the two values was then used to determine hourly rates. Correlation coefficients between the sinus rhythm and pacing rates were calculated. In nine patients, pacing rates correlated well to sinus rhythm (range 0.6793-0.9558. P < 0.001 and P < 0.05), whereas in two cases correlation was not sufficient (P > 0.05). Most of the patients, in whom rate response factor (RRF) measurements during peak exercise by treadmill with chronotropic assessment exercise protocol were performed and pacemakers were programmed to these parameters, had more appropriate ventricular rates compared to spontaneous sinus rates. In these patients mean median 15). This study shows that during daily activities minute ventilation rate adaptive pacemakers can achieve pacing rates well correlated to sinus rhythm that reflects the physiological heart rate iu chiidren. (PACE 1998; 21[Pt. I]: 2100 21[Pt. I]: -2104 rate responsive pacemaker, minute ventilation, children Address for reprints: Alpay ^eliker. M.D.

Research paper thumbnail of Comparison of Mid-term Clinical Experience with Steroid-Eluting Active and Passive Fixation Ventricular Electrodes in Children

Pacing and Clinical Electrophysiology, 2000

CEVIZ, N., ET AL: Comparison of Mid-term Clinical Experience with Steroid-Eluting Active and Pass... more CEVIZ, N., ET AL: Comparison of Mid-term Clinical Experience with Steroid-Eluting Active and Passive Fixation Ventricular Electrodes in Children. Although active fixation ventricular leads seem to have advantages over passive fixation leads, this study compares the follow-up results of active and passive fixation leads in children. We evaluated the implantation and follow-up data of 41 children with active (Accufix II DEC, group 1) (n = 20) or passive (Membrane E. group 2) (n = 21) fixation, steroid-eluting ventricularleads. All but one of the patients in group 1 completed the 12-month follow-up. The mean follow-up period in group 2 was 10.4 ± 2.9 months (range 3-12 months, median 12 months). In both groups the mean pacing threshold was measured as 0.51 ± 0.09 V versus 0.48 ± 0.15 V (P > 0.05) at 0.5-ms pulse width, mean R wave amplitude as 9.9 ± 2.5 mV versus 9.4 ± 3.2 mV (P > 0.05), and mean impedance as 557 i 92 il versus 664 ± 160 (2 (P < 0.05), respectively, at implantation. After the first week of pacing, mean threshold values in group 1 were significantly lower than those of group 2 (P < 0.01 and P < 0.05, respectively). During the follow-up period, lead impedance measurements did not show a significant difference between the two groups. In one patient from group 1. the lead (by unscrewing) was removed easily because of pacemaker pocket infection. No lead dislodgement or helix deformation occurred in group 1. Nevertheless, in one patient from group 2, the lead was extracted at 4-month postimplantation because of lead displacement. We conclude that the steroid-eluting active fixation lead (Accufix II DEC) have advantages of easier implantation and lower acute and chronic stimulation thresholds compared to the passive fixation lead (Membrane E). Therefore, Accufix II DEC is superior to Membrane E, and it is a better first choice in children with an implanted single chamber ventricular pacemaker. (PACE 2000; 23:1245-1249 steroid elution, active fixation lead, passive fixation lead, children Address for reprints: Alpay Celiker, M.D., Cardiology Unit. Department

Research paper thumbnail of Comparison of Sensitivity and Specificity of Tilt Protocols with and without Isoproterenol in Children with Unexplained Syncope

Pacing and Clinical Electrophysiology, 1997

Syncope. Head-up tilt testing with or without isoproterenol is extensively used in the evaluation... more Syncope. Head-up tilt testing with or without isoproterenol is extensively used in the evaluation of patients with unexplained syncope. However, sensitivity and specificity of tilt protocols with and without isoproterenol have not been clarified in children, due to lack of age matched control subjects. This study was designed to assess and to compare the sensitivity and specificity of tilting alone and tilting in conjunction with isoproterenol. Thirty children with unexplained syncope (group I) and 15 age-matched control subjects (control group 1) underwent successive 60° head-up tilts for 10 minutes during infusions of 0.02, 0.04, and 0.06 fig/kg/min of isoproterenol, after a baseline tilt to 60°f or 25 minutes. Also, 35 children (group II) with unexplained syncope and 15 healthy control subjects (control group II) were evaluated by head-up tilt to 60° for 45 minutes without an infusion of isoproterenol.

Research paper thumbnail of Calpain-3 Deficiency Causes a Mild Muscular Dystrophy in Childhood

Neuropediatrics, 1997

Among our 20 families with LGMD2, 10 were documented to have muscle-specific calcium-activated ne... more Among our 20 families with LGMD2, 10 were documented to have muscle-specific calcium-activated neutral protease 3 (calpain-3) deficiency. Consanguinity was present in all. The current ages of the index cases were between 12 and 23 years, and there were additional nine members affected. Clinically, the patients showed mild courses; none of the cases below age 30 lost autonomy so far. The dystrophy is mainly proximal and atrophic with calf enlargement and scapular wasting in some. In three cases walking was delayed. Creatine kinase levels were at least 10 times elevated. All obligate carriers had normal creatine kinase levels. Five families shared the same 551 delA frameshift mutation. In four of these families there was the same core haplotype, whereas one was distinct suggesting an independent origin. Calpain-3 deficiency in general is a mild muscular dystrophy during childhood.

Research paper thumbnail of Dysrhythmia as a cause of syncope in children without neurological or cardiac morphological abnormalities

Pediatrics International, 2002

Background : Arrhythmias are among the malignant causes of syncope. This study has been undertake... more Background : Arrhythmias are among the malignant causes of syncope. This study has been undertaken to determine the relative incidence and significance of dysrhythmia in the pathogenesis of syncope among patients referred to a pediatric cardiology unit. Methods : Between March 1997 and March 1999, 105 consecutive patients (59 female, 46 male) aged 11.5 ± 3.6 years without neurologic or cardiac morphologic causes were evaluated for at least one episode of syncope. A pediatric cardiologist and a pediatric neurologist evaluated all the patients. Routine chest X‐ray, 12‐lead electrocardiogram (ECG), electroencephalography (EEG), 24‐h Holter monitoring and echocardio­graphy were carried out. When deemed necessary, further tests were undertaken for the cases of syncope which were unexplained by routine tests. Results : The cause of syncope was identified as vasovagal in 25.7% (n = 27) and related to dysrhythmia in 30.5% (n = 32). The cause was migraine‐associated syncope in two children, ...

Research paper thumbnail of Double-chambered right ventricle: experience with 52 cases

International Journal of Cardiology, 1995

The presence of anomalous muscle bundles may produce a pressure gradient between the inflow and o... more The presence of anomalous muscle bundles may produce a pressure gradient between the inflow and outflow portions of the right ventricle, thus resulting in double-chambered right ventricle bearing troublesome clinically in its diagnosis. The aim of the present study was to review the diagnostic criteria. Fifty-two patients with a double-chambered right ventricle were seen during an &year period. They ranged in age at the catheterization from 4 months to 17 years (mean 7.5 f 4.4 years). Diagnosis was confirmed in 51 patients at cardiac catheterization and in other one on operation. The majority of the patients had associated cardiac anomalies: there were 33 ventricular septal defect (63%), 21 pulmonary valve stenosis (40%), nine atria1 septal defect (17%), and four double-outlet right ventricle. The electrocardiograms revealed upright T waves alone in right precordial leads suggesting right ventricular hypertrophy in 33% of the patients. At cardiac catheterization, there was a pressure gradient of 20-160 mmHg between the right ventricular inflow and outflow portions. Forty patients have had surgery and four have undergone balloon pulmonary valvuloplasty. Surgical treatment was planned for two patients and other six had no indication for treatment.

Research paper thumbnail of Çocukluk Çağı Taşikardilerinin Tanı ve Tedavisinde Adenozinin Yeri

Turkiye Klinikleri Journal of Cardiology, 1994

Research paper thumbnail of Surgical treatment in tetralogy of Fallot diagnosed by echocardiography

International Journal of Cardiology, 1992

Surgical treatment in tetralogy of Fallot diagnosed by echocardiography. Int J Cardiol 1992;37:32... more Surgical treatment in tetralogy of Fallot diagnosed by echocardiography. Int J Cardiol 1992;37:329-335.

Research paper thumbnail of Active-fixation, steroid-eluting ventricular leads: the medium-term results in children

Anadolu kardiyoloji dergisi : AKD = the Anatolian journal of cardiology, 2005

Low threshold characteristics and mechanical stability are important features of an ideal pacing ... more Low threshold characteristics and mechanical stability are important features of an ideal pacing lead, especially for children. We report our experience and medium-term results with a steroid-eluting, active-fixation ventricular lead in children. Telectronics Accufix II DEC model 033-212 ventricular leads were implanted in 21 patients. Eighteen patients (11 male / 7 female; 10.6+/-4.0 years), who were followed for a mean period of 6.47 +/-1.13 years, were included in the study. Pacemaker mode was DDDR in three patients, and VVIR in the remaining 15 patients. Mean threshold value was 0.5 volts at implant, which increased to 0.7 volts in the first month (p>0.05). It remained stable (0.62-0.78 V) until 5.5 years (p>0.05), increased significantly at 5.5 years (0.99+/-0.63 V at 5.5 years, p<0.05) and remained significantly high after this time (p<0.05). Pacing lead impedance did not differ significantly throughout the study (p>0.05). Thirteen pulse generators reached end-o...

Research paper thumbnail of Dual chamber cardiac pacing in children: Single chamber pacing dual chamber sensing cardiac pacemaker or dual chamber pacing and sensing cardiac pacemaker?

Pediatrics International, 2002

Background : Dual chamber pacemakers (single chamber pacing dual chamber sensing cardiac pacemake... more Background : Dual chamber pacemakers (single chamber pacing dual chamber sensing cardiac pacemaker (VDD) and dual chamber pacing and sensing cardiac pacemaker (DDD)) are being used frequently in children and adolescents. The aim of this study was to verify the safety and performance of the VDD and DDD pacing systems, and to evaluate the differences between two pacing modes with regard to atrial sensing and tracking functions. Methods : In this study, we evaluated 14 patients with VDD pacing and 15 patients with DDD pacing between 1994 and 2000. In the patient group with VDD pacing, all had congenital or acquired atrioventricular (AV) block. In the patient group with DDD pacing, 11 had congenital or acquired AV block, three had sinus node dysfunction with AV conduction disturbance and one had idiopathic hypertrophic subaortic stenosis. Twentyeight devices were implanted in the subpectoral area using the transvenous route. After implantation the atrial tracking capabilities of the pacing systems were analyzed by telemetry, Holter monitoring, and treadmill exercise testing. Results : The mean age of patients in the VDD pacing group was younger. The percentage of congenital heart disease was higher in the DDD pacing group. There was no significant difference regarding fluoroscopy time during implantation and follow-up time between the two groups. During implantation, in the VDD pacing group the mean sensed atrial signal was 3.1 ± 1.3 mV and this decreased to 1.37 ± 0.68 mV ( P < 0.05) during follow-up. This pattern was also observed in DDD group (3 ± 2 mV vs 1.9 ± 1.5 mV, P < 0.05). Although the P wave measurement at implantation did not differ between the two groups, it was significantly higher in the DDD pacing group at the last control. Three patients with VDD pacing were reprogrammed to VVI or single chamber pacing and sensing, rate adaptive cardiac pacemaker because of complete loss of AV synchrony. There was no atrial sensing problem in the DDD pacing group. During the follow-up, one patient with VDD pacing developed diaphragmatic stimulation and required lead revision. In one patient with DDD pacing, venous thrombosis occurred in the right subclavian vein and was treated with thrombolytic therapy. During treadmill exercise testing, in one patient with VDD and one patient with DDD pacing temporary failure of atrial sensing occurred. At 24 h Holter monitoring, intermittent loss of atrial sensing was documented in two patients with VDD pacing. Conclusions : Dual chamber pacing in children with DDD or VDD pacemakers is a suitable method for bradycardia treatment. Atrial sensing problems may occur in VDD pacemakers. Therefore, DDD pacing mode should be preferred whenever suitable for the patient to maintain the AV synchrony.

Research paper thumbnail of Evaluation by exercise testing of children with mild and moderate valvular aortic stenosis

Pediatrics International, 2000

The aim of the present paper was to determine the factors related to sudden death in aortic steno... more The aim of the present paper was to determine the factors related to sudden death in aortic stenosis. The factors related to sudden death were investigated in 40 asymptomatic children with mild and moderate aortic stenosis by treadmill testing. The QT interval of aortic stenosis cases were significantly longer than those of healthy children with increasing heart rates during exercise. A longer QT interval of aortic stenosis cases compared to normal children during exercise is the first sign of myocardial ischemia and leads to fatal ventricular arrhythmias and sudden death. For this reason we recommend that exercise testing should be performed frequently in aortic stenosis patients and that close follow up is necessary for patients with long QT segments that can be a marker for severe arrhythmias.

Research paper thumbnail of Dual Sensor Pacemakers in Children: What is the Choice of Sensor Blending?

Pacing and Clinical Electrophysiology, 1997

Dual sensor pacemakers were developed to obtain more appropriate responses to activity. We evalua... more Dual sensor pacemakers were developed to obtain more appropriate responses to activity. We evaluated ten children with dual sensor pacemakers in different sensor blending circumstances using exercise testing to assess which ratio was optimal. Ten patients with several bradydysrhythmias (ages 6-16 years; mean 10.1 years) were included in the study. Eight patients had VVIR pacemakers (Vitatron Topaz), models and two patients had VDD pacemakers implanted via the transvenous route. All patients were in a paced rhythm (98.5% pacing). Accurate T wave sensing ranged from 81%-100%; mean 92%, median 95%. Voluntary exercise testing with a CAEP protocol was performed using a treadmill with the pacemaker in VVIR mode. Medium activity threshold with three sensor blending ratios (QT = ACT, QT &gt; ACT, and QT &lt; ACT) were done in all patients. The mean duration of exercise was not statistically different among the three sensor blending ratios. After 90 seconds of exercise, the mean pacing rate had increased by 12%, 3%, and 5%, respectively, in the three groups. At maximal exercise, the increases were 45%, 42%, and 54%. Mean HRs during exercise in each of the three ratios were not significantly different, although we found a statistically significant increase in HR during the first two stages of rest period in the QT = ACT sensor blending ratio compared to the QT &gt; ACT ratio. No difference was observed after the second stage. (1) there is no difference between the QT = ACT, QT &lt; ACT, and QT &gt; ACT sensor blending ratios; and (2) each child has to be evaluated by exercise testing to program a correct sensor blending ratio.

Research paper thumbnail of Sotalol in treatment of pediatric cardiac arrhythmias

Pediatrics International, 2001

Research paper thumbnail of Dysrhythmia as a cause of syncope in children without neurological or cardiac morphological abnormalities

Pediatrics International, 2002

Background : Arrhythmias are among the malignant causes of syncope. This study has been undertake... more Background : Arrhythmias are among the malignant causes of syncope. This study has been undertaken to determine the relative incidence and significance of dysrhythmia in the pathogenesis of syncope among patients referred to a pediatric cardiology unit. Methods : Between March 1997 and March 1999, 105 consecutive patients (59 female, 46 male) aged 11.5 ± 3.6 years without neurologic or cardiac morphologic causes were evaluated for at least one episode of syncope. A pediatric cardiologist and a pediatric neurologist evaluated all the patients. Routine chest X-ray, 12-lead electrocardiogram (ECG), electroencephalography (EEG), 24-h Holter monitoring and echocardiography were carried out. When deemed necessary, further tests were undertaken for the cases of syncope which were unexplained by routine tests. Results : The cause of syncope was identified as vasovagal in 25.7% ( n = 27) and related to dysrhythmia in 30.5% ( n = 32). The cause was migraine-associated syncope in two children, psychogenic syncope in three children and orthostatic hypotension in one patient. The cause was unknown in 36.2% ( n = 38). Conclusion : We conclude that dysrhythmia is a significant and frequent cause in children referred to pediatric cardiology units. The combination of ECG, Holter monitoring, electrophysiologic study, transtelephonic ECG and head-up tilt test can identify the underlying cause of syncope in as many as 58% of these patients that present with syncope.

Research paper thumbnail of Effectiveness and safety of intravenous amiodarone in drug-resistant tachyarrhythmias of children

Pediatrics International, 1998

B a c k g r o d Experience with pediatric use of intravenous amiodarone is limited. In this study... more B a c k g r o d Experience with pediatric use of intravenous amiodarone is limited. In this study, our experiences with intravenous amiodarone in children with acute life-threatening or chronic tachyarrhythmias are reviewed.

Research paper thumbnail of Body mass index and lipid levels in children from Ankara, Turkey versus Bogalusa, Louisiana

Preventive Medicine, 2005

Background: Turkish Heart Study demonstrated that low high density lipoprotein cholesterol levels... more Background: Turkish Heart Study demonstrated that low high density lipoprotein cholesterol levels are prevalent among Turkish adults. Methods: We compared body mass index and lipid levels of Turkish children (n = 1525, ages 10 -17) with the bi-racial community of Bogalusa Heart Study.

Research paper thumbnail of Facioscapulohumeral syndrome with cardiomyopathy

Postgraduate Medical Journal, 1990

Research paper thumbnail of Parameters of iron deficiency in children with cyanotic congenital heart disease

Pediatric Cardiology, 1996

A group of 67 children with cyanotic congenital heart disease (CCHD) were studied, and 35 were gi... more A group of 67 children with cyanotic congenital heart disease (CCHD) were studied, and 35 were given iron treatment according to a regimen that gives iron to patients with a hematocrit (Hct) below 60%. The patients were categorized as iron-deficient and ironsufficient according to their transferrin saturation and ferritin values. The pretreatment hemoglobin (Hb) and Hct values of the groups were similar. The mean Hct was nearly three times as much as the mean Hb in the ironsufficient group and more than three times as much as the Hb in the iron-deficient group. Excessive erythrocytosis in the iron-deficient group was impressive. Mean corpuscular volume (MCV) values were below 72.7 fl in all of the iron-deficient patients. After treatment the Hb, Hct, transferrin saturation, and ferritin increased significantly in both groups, with the increments greater in the iron-deficient group. Increments in the erythrocyte (RBC) count were significant in the iron-sufficient group but insignificant in the iron-deficient one. Increments of MCV in the iron-deficient group were significant but insignificant in the iron-sufficient group. Our study demonstrated that prediction of Hb, RBC count, and MCV, measurements of which are easy and inexpensive and require little blood, can suffice for the diagnosis of iron deficiency in patients with CCHD without altering systemic perfusion.

Research paper thumbnail of Head-up tilt test: A highly sensitive, specific test for children with unexplained syncope

Pediatric Cardiology, 1996

Unexplained syncope may cause diagnostic and therapeutic problems in children. The head-up tilt t... more Unexplained syncope may cause diagnostic and therapeutic problems in children. The head-up tilt test has been shown to be a useful tool for investigating unexplained syncope, especially for diagnosis of neurally mediated syncope. In this study 20 patients aged 9-18 years (12.0 ± 2.5 years) with syncope of unknown origin and 10 healthy age-matched children were evaluated by head-up tilt to 60°for 25 minutes. The test was considered positive if syncope or presyncope developed in association with hypotension, bradycardia, or both. If tilting alone did not induce symptoms (syncope or presyncope), isoproterenol infusion was administered with increasing doses (0.02-0.08 g/kg per minute). During the tilt test, symptoms were elicited in 15 (75%) of the patients with unexplained syncope but in only one (10%) of the control group (p < 0.001). The sensitivity of the test was 75% and its specificity 90%. Three patterns of response to upright tilt were observed in symptomatic patients: vasodepressor pattern with an abrupt fall in blood pressure in 67%; cardioinhibitory pattern with profound bradycardia in 6%; and mixed pattern in 27%. In patients with positive head-up tilt, there were sudden decreases in systolic blood pressure (from 130 ± 15 to 61 ± 33 mmHg) and in mean heart rate (from 147 ± 26 to 90 ± 38 beats per minute) (p < 0.001) during symptoms. Treatments with atenolol 25 mg/day has shown complete suppression of syncope in positive responders during a mean follow-up period of 18 ± 6 months. The head-up tilt test is a noninvasive, sensitive, specific diagnostic tool for evaluating children with unexplained syncope.

Research paper thumbnail of Influence of D-Net (EUROPEAN GSM-Standard) Cellular Telephones on Implanted Pacemakers in Children

Pacing and Clinical Electrophysiology, 2002

Research paper thumbnail of Comparison of Normal Sinus Rhythm and Pacing Rate in Children with Minute Ventilation Single Chamber Rate Adaptive Permanent Pacemakers

Pacing and Clinical Electrophysiology, 1998

A., ET AL.: Comparison of Normal Sinus Rhythm and Pacing Rate in Children with Minute Ventilation... more A., ET AL.: Comparison of Normal Sinus Rhythm and Pacing Rate in Children with Minute Ventilation Single Chamher Rate Adaptive Permanent Pacemakers. Bate adaptive pacemakers are used to achieve a better cardiac performance during exercise by increasing the heart rate and cardiac output. The ideal rate adaptive sensor should be able to mimic sinus node modulation under various degrees of exercise and other metabolic needs. Minute ventilation sensing has proven to be one of the most accurate sensor systems. In this study, alterations in sinus rhythm and pacing rates during daily life conditions in 11 children (median age 11 years, range 6-14 years) with minute ventilation single chamber pacemakers were investigated. Correlation of sinus rhyihm with pacing rates was assessed. ECG records were obtained from 24-hour Holter monitoring. Average rates of five consecutive P waves and pace waves were determined every half hour. The average of the two values was then used to determine hourly rates. Correlation coefficients between the sinus rhythm and pacing rates were calculated. In nine patients, pacing rates correlated well to sinus rhythm (range 0.6793-0.9558. P < 0.001 and P < 0.05), whereas in two cases correlation was not sufficient (P > 0.05). Most of the patients, in whom rate response factor (RRF) measurements during peak exercise by treadmill with chronotropic assessment exercise protocol were performed and pacemakers were programmed to these parameters, had more appropriate ventricular rates compared to spontaneous sinus rates. In these patients mean median 15). This study shows that during daily activities minute ventilation rate adaptive pacemakers can achieve pacing rates well correlated to sinus rhythm that reflects the physiological heart rate iu chiidren. (PACE 1998; 21[Pt. I]: 2100 21[Pt. I]: -2104 rate responsive pacemaker, minute ventilation, children Address for reprints: Alpay ^eliker. M.D.

Research paper thumbnail of Comparison of Mid-term Clinical Experience with Steroid-Eluting Active and Passive Fixation Ventricular Electrodes in Children

Pacing and Clinical Electrophysiology, 2000

CEVIZ, N., ET AL: Comparison of Mid-term Clinical Experience with Steroid-Eluting Active and Pass... more CEVIZ, N., ET AL: Comparison of Mid-term Clinical Experience with Steroid-Eluting Active and Passive Fixation Ventricular Electrodes in Children. Although active fixation ventricular leads seem to have advantages over passive fixation leads, this study compares the follow-up results of active and passive fixation leads in children. We evaluated the implantation and follow-up data of 41 children with active (Accufix II DEC, group 1) (n = 20) or passive (Membrane E. group 2) (n = 21) fixation, steroid-eluting ventricularleads. All but one of the patients in group 1 completed the 12-month follow-up. The mean follow-up period in group 2 was 10.4 ± 2.9 months (range 3-12 months, median 12 months). In both groups the mean pacing threshold was measured as 0.51 ± 0.09 V versus 0.48 ± 0.15 V (P > 0.05) at 0.5-ms pulse width, mean R wave amplitude as 9.9 ± 2.5 mV versus 9.4 ± 3.2 mV (P > 0.05), and mean impedance as 557 i 92 il versus 664 ± 160 (2 (P < 0.05), respectively, at implantation. After the first week of pacing, mean threshold values in group 1 were significantly lower than those of group 2 (P < 0.01 and P < 0.05, respectively). During the follow-up period, lead impedance measurements did not show a significant difference between the two groups. In one patient from group 1. the lead (by unscrewing) was removed easily because of pacemaker pocket infection. No lead dislodgement or helix deformation occurred in group 1. Nevertheless, in one patient from group 2, the lead was extracted at 4-month postimplantation because of lead displacement. We conclude that the steroid-eluting active fixation lead (Accufix II DEC) have advantages of easier implantation and lower acute and chronic stimulation thresholds compared to the passive fixation lead (Membrane E). Therefore, Accufix II DEC is superior to Membrane E, and it is a better first choice in children with an implanted single chamber ventricular pacemaker. (PACE 2000; 23:1245-1249 steroid elution, active fixation lead, passive fixation lead, children Address for reprints: Alpay Celiker, M.D., Cardiology Unit. Department

Research paper thumbnail of Comparison of Sensitivity and Specificity of Tilt Protocols with and without Isoproterenol in Children with Unexplained Syncope

Pacing and Clinical Electrophysiology, 1997

Syncope. Head-up tilt testing with or without isoproterenol is extensively used in the evaluation... more Syncope. Head-up tilt testing with or without isoproterenol is extensively used in the evaluation of patients with unexplained syncope. However, sensitivity and specificity of tilt protocols with and without isoproterenol have not been clarified in children, due to lack of age matched control subjects. This study was designed to assess and to compare the sensitivity and specificity of tilting alone and tilting in conjunction with isoproterenol. Thirty children with unexplained syncope (group I) and 15 age-matched control subjects (control group 1) underwent successive 60° head-up tilts for 10 minutes during infusions of 0.02, 0.04, and 0.06 fig/kg/min of isoproterenol, after a baseline tilt to 60°f or 25 minutes. Also, 35 children (group II) with unexplained syncope and 15 healthy control subjects (control group II) were evaluated by head-up tilt to 60° for 45 minutes without an infusion of isoproterenol.

Research paper thumbnail of Calpain-3 Deficiency Causes a Mild Muscular Dystrophy in Childhood

Neuropediatrics, 1997

Among our 20 families with LGMD2, 10 were documented to have muscle-specific calcium-activated ne... more Among our 20 families with LGMD2, 10 were documented to have muscle-specific calcium-activated neutral protease 3 (calpain-3) deficiency. Consanguinity was present in all. The current ages of the index cases were between 12 and 23 years, and there were additional nine members affected. Clinically, the patients showed mild courses; none of the cases below age 30 lost autonomy so far. The dystrophy is mainly proximal and atrophic with calf enlargement and scapular wasting in some. In three cases walking was delayed. Creatine kinase levels were at least 10 times elevated. All obligate carriers had normal creatine kinase levels. Five families shared the same 551 delA frameshift mutation. In four of these families there was the same core haplotype, whereas one was distinct suggesting an independent origin. Calpain-3 deficiency in general is a mild muscular dystrophy during childhood.