Alpay Çeliker

Double-chambered right ventricle: experience with 52 cases

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 8-year period. They ranged in age at the catheterization from 4 months to 17 years (mean 7.5 +/- 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 atrial 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.

Comparison of acute hemodynamic effects of aerosolized and intravenous iloprost in secondary pulmonary hypertension in children with congenital heart disease

Both aerosolized and intravenous infusion of iloprost caused a significant decrease in mean pulmonary artery pressure and pulmonary vascular resistance. Although intravenous infusion caused a large decrease in mean systemic arterial pressure, this was only slightly affected by aerosolized iloprost. Aerosolized iloprost caused a significant decrease in the pulmonary-to-systemic vascular resistance ratio; however, intravenous infusion did not cause a prominent decrease in this ratio.

Transcatheter closure of patent ductus arteriosus with Nit-Occlud coils

The detachable coils have been successfully used for transcatheter occlusion of small‐ to moderate‐sized patent ductus arteriosus (PDA). We report our experience regarding the use of the Nit‐Occlud coils (NOCs) for transcatheter PDA and major aortopulmonary collateral (MAPCA) occlusion. Single NOCs were used to close PDA in 26 patients, and one small and two large MAPCAs in two patients. Mean age and weight of the patients were 7.7 ± 5.4 years and 20.6 ± 11.6 kg. Mean minimum duct diameter was 2.8 ± 0.8 mm; ampulla, 8.7 ± 2.4 mm; and PDA length, 9.3 ± 4.4 mm. Mean pulmonary artery pressure ranged from 9 to 51 mm Hg and pulmonary/systemic flow ratio from 1.1 to 5.8. Ductal shape was conical in 24 patients. Route of approach was venous in 23 and arterial in 3. Successful coil implantation was achieved in 24/26 (92.3%). Mean procedure and fluoroscopy time were 67.2 ± 22.1 and 14.9 ± 6.5 min. The three MAPCAs were also successfully occluded using NOC Medium and Flex. Postimplantation angiograms revealed no leak in 3, a trace or small leak in 17, and a medium leak in 4 patients. Mean follow‐up was 7 ± 5 months. Complete occlusion was achieved in 17/24 (71%) at 24 hr, 19/24 (79%) by 1 month, 13/15 (87%) by 3 months, 14/15 (93%) by 6 months, and 10/11 (90%) by 12 months postprocedure. Hemolysis, late embolization, duct recanalization, and flow disturbances were not observed. Transcatheter occlusion of moderate‐sized PDAs and MAPCAs using NOCs seems to offer a safe, simple, and controlled method in pediatric patients. Catheter Cardiovasc Interv 2005

Heart rate variability in diabetic children: Sensitivity of the time- and frequency-domain methods

SummaryHeart rate variability (HRV) is a noninvasive index of the neural activity of the heart. Although also influenced by the sympathetic activity of the heart, HRV is essentially determined by the vagal stimulation of the heart. Several HRV abnormalities have been described in adults with diabetes mellitus. However, there are few data on HRV in children with diabetes mellitus. In the present study, HRV was assessed in seven healthy children, 10 diabetic children with good glycemic control and 11 diabetic children with poor glycemic control. All had normal standard cardiac autonomic function tests, obtained from 24-h Holter tapes. HRV was measured by calculating six time-domain (mean R-R interval (RR), standard deviation of the R-R interval [SDRR], standard deviation of the mean of 288 R-R intervals [SDANN], the mean of the 288 standard deviations computed for each 5-min period [SD], percentage of differences of adjacent R-R intervals of >50 msec for the entire 24 h [pNN50], and the root mean square of successive differences [rMSSD]) and four frequency-domain (low frequency [LF], high frequency [HF], total heart rate power spectra, and LF/HF ratio) indexes. SD, pNN50, rMSSD, LF, HF and total heart rate power spectra were markedly and significantly reduced in diabetic children with poor metabolic control. The 24-h variation of low- and high-frequency components of heart rate power spectra of the latter children had a differet shape. Thus, diabetic children with poor metabolic control (elevated HbA1c and B2M levels) have a low HRV compared to those diabetic children with good control and healthy chidren. These results can be interpreted as evidence of cardiac autonomic neuropathy in diabetic children with asymptomatic diabetic autonomic neuropathy.

Thoracic sequels after thoracotomies in children with congenital cardiac disease

The standard surgical approach for closed heart procedures in small infants and children is to use a posterolateral thoracotomy incision, which results in the division of the latissimus dorsi and serratus anterior muscles. The aim of our study was to determine the frequency and type of musculoskeletal deformities in children undergoing surgery with this approach for congenital cardiac disease. We included 49 children, 28 boys and 21 girls, in the study. Their mean age was 10.2 +/- 4.8 years, the mean age at the time of surgery was 3.8 +/- 4.0 years, and they were evaluated at an average of 6 years after the thoracotomy. Of the patients, 94% had various musculoskeletal deformities. Scoliosis was observed in 15 patients (31%) but only in two patients did the curves exceed 25 degrees. Of these patients, three-fifths had aortic coarctation. Elevation of the shoulder was seen in 61%, winged scapula in 77%; while 14% had asymmetry of the thoracic wall due to the atrophy of the serratus anterior muscle. Deformity of the thoracic cage was observed in 18%; and 63% had asymmetry of the nipples. Thus, we found that musculoskeletal deformities are frequent after thoracotomies in children with congenital cardiac disease. Patients who have undergone such procedures for cardiac or noncardiac surgery should be followed until their skeletal maturation is complete. Techniques sparing the serratus anterior and latissimus dorsi muscles should be preferred. These adverse effects of thoracotomy may be another reason for using interventional procedures in these cases.

HEAD-UP TILT TEST : A HIGHLY SENSITIVE, SPECIFIC TEST FOR CHILDREN WITH UNEXPLAINED SYNCOPE

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 μg/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.

Clinical experiences of patients with catecholaminergic polymorphic ventricular tachycardia.

Catecholaminergic polymorphic ventricular tachycardia is a rare entity that can occur in children without cardiac disease and with a normal QT interval. It may cause syncope, convulsions, and sudden death during physical activity or emotional distress. We report the clinical features, treatment, and follow-up of 16 children with this diagnosis, emphasizing the potentially fatal nature of the disease.The mean age of patients at the onset of symptoms and at the time of diagnosis was 7.8 plus or minus 2.5 years, and 10.6 plus or minus 3.5 years, respectively. Syncope was the main complaint in 11, and 7 were treated as erroneously as having epilepsy. Diagnosis was confirmed by exercise and/or infusion of isoproterenol. Once the diagnosis was made, we started propranolol in all patients, and added verapamil if ventricular tachycardia was still inducible on a treadmill exercise test. An intracardiac defibrillator was implanted in 4 patients. Of the 16 patients, 4 died suddenly, giving a rate of mortality of 25%. In 2 of those dying suddenly, there was evidence of poor compliance to the recommended treatment. Another 2 patients had been resuscitated because of sudden cardiac arrest.Catecholaminergic polymorphic ventricular tachycardia must be considered in the differential diagnosis of syncope in children without heart disease but with a normal QT interval. Medical treatment with propranolol and verapamil may decrease the incidence of arrhythmia. Implantation of intracardiac defibrillators should be considered in those resistant to drug therapy. Delay in diagnosis, and inadequate treatment, can result in sudden cardiac death.

The effects of sevoflurane and desflurane anesthesia on QTc interval and cardiac rhythm in children

Background:  Inhalational anesthetics may prolong QTc interval (QT interval corrected for heart rate) of the ECG and cause life‐threathening arrythmias. The effects of desflurane on QTc interval and cardiac rhythm have not been reported previously in children. We assessed the effects of desflurane anesthesia on QTc interval and cardiac rhythm and compared them with sevoflurane anesthesia in children.

Rhythm abnormalities in children with isolated ventricular noncompaction.

Background: Isolated ventricular noncompaction (IVNC) is a serious cardiomyopathy with a generally poor prognosis. It is characterized by the presence of prominent ventricular myocardial trabeculations and deep intertrabecular recesses, in the absence of other structural heart defects. This cardiomyopathy is usually associated with ventricular dysfunction, thromboembolic events, and rhythm problems.

Effectiveness and safety of intravenous amiodarone in drug‐resistant tachyarrhythmias of children

Background: 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.