Long-term results of endocardial pacing with Autocapture™ threshold tracking pacemakers in children

AIM

We aimed to evaluate the long-term results of endocardial pacing with Autocapture threshold tracking pacemakers in children.

METHODS AND RESULTS

Implantation and follow-up data of 20 children with these pacemakers were retrospectively evaluated. The pacemakers were implanted subpectorally in five and subcutaneously in 15 patients. The indication for pacing was high-grade atrioventricular block in 18 cases. The mean age at implantation was 7+/-4.8 years. Four patients were pacemaker dependant (heart rate < 30 bpm). At implantation, the mean pacing threshold was 0.5 V at 0.5 ms. The mean evoked response (ER) signal was 8.5+/-3.6 mV, and the polarisation signal (PS) was <1 mV in 15 patients and 1-2 mV in five patients. During the mean follow-up period of 60 months, mean ER signal decreased significantly to 7.7+/-6.3 mV at 24 months and 6.5+/-2.5 mV at 60 months (P < 0.05). In four of 15 patients (26.6%), with a predischarge PS value of <1 mV, it increased between 1 and 2 mV over time. During follow-up, autocapture function was deactivated in six (30%) patients; due to inappropriate ER/PS values in four and due to severe muscle twitching in two with subpectoral implants. These problems occurred during a median period of 21 months after implantation. Generators were replaced in three patients with Microny pacemakers because of battery depletion at 54, 66 and 78 months. In two of them autocapture function had been working since implantation. In seven of 10 patients, who completed > or = 60 months of follow-up, battery impedances were still at the predischarge level.

CONCLUSIONS

Autocapture function works well in most children at implantation. Mean ER signal significantly decreases over time despite stable pacing parameters. Autocapture function may become nonoperational due to decreased ER signal in some patients. Muscle twitching may be an important problem that may result in discontinuation of autocapture function in children with subpectoral implants.

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.

METHODS AND RESULTS

This article describes 11 children who have rhythm abnormalities associated with IVNC. On admission, eight children had complaints including palpitation, syncope, heart failure, and bradycardia. Ventricular arrhythmias were diagnosed in four children, sinus node and atrioventricular conductance disturbances in six children, and Wolff-Parkinson-White syndrome and associated tachycardia in one child. Three children with ventricular arrhythmias received an automatic implantable cardioverter defibrillator (ICD). Three patients died of cardiac problems during the follow-up period.

CONCLUSION

Since many of rhythm abnormalities, including life-threatening ventricular arrhythmias, may be seen in patients with IVNC, children with IVNC should be screened for arrhythmias. An ICD may be the best treatment for some of these patients.

Cardiac dysrhythmias after transcatheter closure of ASD with Amplatzer device

Transcatheter closure of atrial septal defect (ASD) has been used as an alternative to open heart surgery. Although transcatheter closure of ASD with the Amplatzer septal occluder is a safe and feasible method in pediatric patients, there is little published data on arrhythmia analysis following transcatheter device closure of secundum ASD. We evaluated cardiac dysrhythmias with 24-hour ambulatory electrocardiographic (ECG) monitoring after transcatheter closure of ASD with Amplatzer device. A total of 85 consecutive patients with ASD underwent transcatheter closure of secundum ASD with Amplatzer device between October 1998 and December 2003. The study involved 65 of these patients assessed by 24-hour ambulatory ECG monitoring. Seven patients were evaluated a second time by 24-hour monitorization. During the procedure, transient complete atrioventricular (AV) block was seen in two patients. One of them returned to normal sinus rhythm in catheterization lab and the other returned to normal sinus rhythm in two hours. Transient junctional rhythm was observed in another patient during the device placement. Twenty-four hour ambulatory ECG monitoring was performed on all patients after a mean four-month period (1-12 months). Holter recordings demonstrated rare supraventricular extrasystole in two patients, rare ventricular premature beats in two patients, and intermittent sinus arrest with sinus pause lasting <1.5 seconds in one patient, for a total of five patients (7.6%). In conclusion, dysrhythmias after transcatheter device closure of secundum ASD with Amplatzer device are rare and benign. We need further long-term follow-up to evaluate late dysrhythmias after the transcatheter device closure of secundum ASD.

Transcatheter closure of interatrial communications with Amplatzer device: results, unfulfilled attempts and special considerations in children and adolescents

OBJECTIVE

We report our clinical experience with the Amplatzer device in transcatheter closure of 80 atrial septal defects (ASD) in children.

METHODS

Among 99 patients (mean age: 7.2+/-3.8 years) with ASD selected by transthoracic echocardiography, procedures were performed in 80 patients under general anesthesia with fluoroscopic and transesophageal echocardiographic (TEE) guidance. Optimal device size was selected after stretched balloon sizing of the ASD's. The patients were discharged at 24 hours after an evaluation with X-ray, electrocardiography and echocardiography.

RESULTS

The mean follow-up period (FUP) was 38+/-14 months. Mean ASD size was 11.5+/-3.7 mm at TEE (stretched size: 17.6+/-3.9 mm). The mean size of the device was 18.6+/-4.0 mm. Procedure and fluoroscopy time were 52.1+/-17.8 minutes and 11.0+/-4.9 minutes, respectively. Immediately after the procedure 35 patients (43.8%) had residual shunts. Trivial shunt remained in only 2 of them (2.5%) after FUP. None of the patients had major complications. Minor and transient rhythm abnormalities were observed in 5 patients and trivial mitral regurgitation was seen in 6 patients.

CONCLUSION

Amplatzer is an effective and safe device for transcatheter closure of ASD especially in pediatric patients.

Childhood acute rheumatic fever in Ankara, Turkey

Patients with acute rheumatic fever (ARF) admitted to a tertiary hospital in Ankara between January 1999 and July 2002 were studied cross-sectionally to verify the clinical profile and were followed during the acute period. All patients were investigated for throat culture, streptococcal serologic study, C-reactive protein, and erythrocyte sedimentation rate, and telecardiograms, electrocardiograms and echocardiographic study were done. During the study period, 129 attacks of ARF were observed: 118 were initial attacks and 11 were recurrences. Age on admission was 11.2 +/- 2.73 years (mean +/- SD, range: 6-21 years). Polyarthritis alone was present in 42 cases (33%), carditis alone in 33 (25%), combined carditis and polyarthritis in 36 (28%), combined carditis and chorea in 15 (12%) and chorea alone in 3 (2%). Nineteen (14%) patients with isolated arthritis and pure chorea had silent mitral and/or aortic regurgitation. Carditis was a dominant presenting manifestation, but appeared to be mild or moderate. The present study indicates that ARF is still a significant problem in Turkey. The observation that 8.5% of the attacks were recurrent reaffirms the need for more effective secondary prevention programs.

Noncompaction of Ventricular Myocardium in a Patient with Congenitally Corrected Transposition of the Great Arteries Treated Surgically: Case Report

Noncompaction of the ventricular myocardium is a rare disorder that represents numerous prominent trabeculations and intratrabecular recesses in the ventricles. It is believed to represent not only an arrest in endomyocardial morphogenesis but also an unclassified cardiomyopathy. The pathology has been almost invariably associated with other congenital cardiac malformations. A female patient with noncompaction of the myocardium of both ventricles and congenitally corrected transposition of the great arteries (cTGA), situs inver-sus totalis, and atrial and ventricular septal defects is described. When she was 7 days old a permanent pacemaker was implanted because of complete heart block. Prazosin (Minipress), an a -receptor blocker, was administered, and the cardiac ejection fraction showed a striking increase from 20% to 42%. Despite careful and regular follow-up evaluations, the general condition of the patient slowly worsened. Five months after surgery she died of hepatorenal failure and low cardiac output. This case report is thought to be the first description of congenital complete heart block, cTGA, and situs inversus totalis with noncompaction of the myocardium of both ventricles.

The significance of P wave duration and P wave dispersion for risk assessment of atrial tachyarrhythmias in patients with corrected tetralogy of Fallot

BACKGROUND

The aim of the present study was to determine the potential role of P wave duration and P wave dispersion for risk assessment of atrial tachyarrhythmias in patients with corrected tetralogy of Fallot (ToF).

METHODS

The maximum P wave duration, minimum P wave duration, and the P wave dispersion from the 12-lead surface electrocardiogram of the patients and controls were measured. Electrophysiological study was performed only in the patient group.

RESULTS

The study group consisted of 25 patients with corrected ToF with a mean age of 16.4 +/- 4.25 years and 25 age-matched healthy control subjects. Patients underwent repair at a mean age of 4.6 +/- 3.41 years (range: 1-19), and the mean duration of follow-up of 11.8 +/- 1.7 years (range: 9-15) after surgery. On electrophysiological study sinus node dysfunction was detected in 3 patients (12%), atrial tachyarrythmias-atrial flutter or fibrillation-in 5 patients (20%), both sinus node dysfunction and atrial flutter in 1 patient (4%), and AV conduction delay in 1 patient (4%). P wave dispersion is significantly higher in patients with atrial tachyarrhythmia inducible by electrophysiological study than in other patients (P < 0.05). A P wave dispersion value of >35 ms has a high predictive accuracy (sensitivity = 83% and specificity = 89%) for inducible atrial tachyarrhythmia in patients with corrected tetralogy of Fallot.

CONCLUSION

P wave dispersion is an easily measured electrocardiographic marker with a good sensitivity and specificity for predicting atrial arrhythmias in patients after correction of ToF.

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.

Interrupted aortic arch in a neonate: multidetector CT diagnosis

We report the usefulness of multidetector CT angiography (CTA) in the diagnosis of interrupted aorta of a neonate. CTA is useful for evaluating malformations of the aortic arch, particularly in cases that cannot undergo conventional angiography or in which detailed information cannot be provided by echocardiography.

Arrhythmogenic right ventricular cardiomyopathy (Naxos disease): report of a Turkish boy

Naxos disease is a recessively inherited arrhythmogenic right ventricular cardiomyopathy in which the cardiac phenotype is associated with palmoplantar keratoderma and woolly hair. This disease is a heart muscle disorder causing life-threatening ventricular arrhythmias, heart failure, and sudden cardiac death. The pathological hallmark of the disease is the progressive replacement of myocardial cells by fat and fibrous tissue. It appears in families descending from the Hellenic island of Naxos. We presented a 13-year-old Turkish boy with Naxos disease associated with ventricular tachycardia because of its rarity, and reviewed the literature.

Transcatheter Embolization of a Coronary Fistula Originating from the Left Anterior Descending Artery by Using N-Butyl 2-Cyanoacrylate

In this report, we describe a successful percutaneous transcatheter n-butyl 2-cyanoacrylate embolization of a coronary fistula originating from the left anterior descending artery in an adolescent with unexpected recurrent attacks of myocardial ischemia.

Adult type anomalous origin of the left coronary artery from the pulmonary artery

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a clinical entity characterized by myocardial necrosis which becomes symptomatic shortly after birth; survival beyond infancy is uncommon because of severe left heart failure. To our knowledge, it is rare for an ALCAPA patient to survive to adulthood. Here we present a case of a 17-year-old girl with ALCAPA who was referred to our hospital because of palpitation and dyspnea.

Cardioverter Defibrillator Implantation in a Child with Isolated Noncompaction of the Ventricular Myocardium and Ventricular Fibrillation

Isolated noncompaction of the ventricular myocardium is a rare unclassified cardiomyopathy and is thought to be due to arrest of myocardial morphogenesis. In fetal life, it is characterized by an excessively prominent trabecular meshwork and deep intratrabecular recesses, and occurs in the left ventricle in the absence of structural heart disease. Echocardiography provides evidence for the diagnosis. The noncompacted ventricular myocardium may be accompanied by depressed ventricular function, systemic embolism, Wolff-Parkinson-White syndrome, left bundle branch block, and ventricular arrhythmia. Although onset of symptoms is frequently delayed until adulthood, symptomatic children have a poor prognosis. In this report, we describe a case of 6-year-old girl who had a history of recurrent syncope. Transthoracic echocardiographic examination showed a localized prominent trabeculation and deep intratrabecular recesses at the inferoapical region of the left ventricle. She had several episodes of ventricular fibrillation which was refractory to pharmacological treatment. An implantable cardioverter defibrillator (ICD) was successfully operated three times during follow-up.

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.

Permanent form of junctional reciprocating tachycardia and tachycardia-induced cardiomyopathy treated by catheter ablation: a case report

The permanent form of junctional reciprocating tachycardia (PJRT) is usually refractory to drug therapy, and these patients are at risk of developing tachycardia-induced cardiomyopathy. The electrocardiogram insribes inverted P waves in leads 2, 3, aVF as well as left lateral leads, along with a P-R interval shorter than R-P interval during the tachycardia. This report describes a three-year-old male patient with PJRT who underwent successful radiofrequency catheter ablation (RFA) of accessory pathway. On transthoracic echocardiography of patient, decreased ventricular systolic function was observed. RFA was performed by applying radiofrequency pulses. Echocardiograms of the patient, two months after catheter ablation, demonstrated progressive improvement of ventricular function. Transcatheter radiofrequency ablation of accessory pathways in patients with PJRT is an effective, and possibly preferable, form of treatment, especially in cases of tachycardia refractory to multiple pharmacologic treatments or when left ventricular dysfunction is present.

Successful radiofrequency catheter ablation therapy of an adolescent with atrial ectopic tachycardia

Atrial ectopic tachycardia is an incessant supraventricular tachycardia and is frequently refractory to medical treatment. Because it can cause tachycardia-induced cardiomyopathy, early diagnosis and treatment is important. We present a 16-year-old boy who was diagnosed as atrial ectopic tachycardia. The tachycardia, originating from the lower region of the right atrium along the crista terminalis was terminated by successful radiofrequency ablation treatment. The tachycardia did not recur in eight months of follow-up.

The influence of mental and physical stress on the autocapture function in children

The Autocapture function detects the evoked response signal (ERS) to verify beat-to-beat capture, and optimizes the output of ventricular pulse amplitude automatically. We had experience concerning the instability of the Autocapture recommendation in some patients. Evoked response is subject to variation as it is a biological event. However, the present knowledge about the Autocapture function lability is very limited. The purpose of this study was to evaluate whether mental stress, body positions or exercise influence the ERS and PS in children. Study was performed in 15 consecutive patients [13.4 +/- 4.1 (5-20) year] with VVIR (n = 10) and DDD/VDD pacemakers with the Autocapture function (n = 5), had received ventricular leads including Membrane-E-1450T (n = 6), Membrane-EX-1470T (n = 2), Tendrill-DX-1388T (n = 3), Tendrill-SDX-1488T (n = 1), AV-Plus-DX-1368 (n = 1), Accufix-II-DEC (n = 1) and Vitatron (n = 1), and followed more than six months. Autocapture functions were measured during arithmetic mental stress test (MST), in different body positions, and during symptom-limited treadmill exercise. MST was applied in all except two (5 and 8 year old) who didn't have ability to perform. Activating autocapture was not recommended in only one with Accufix-II-DEC due to high PS. ERS was 10.5 +/- 6.3 mV during supine and increased to 11.9 +/- 7.5 mV during sitting (p = 0.017) and standing 12.1 +/- 7.2 (p = 0.002). However, ERS remained stable before, during and after both exercise and MST, which were 12.6 +/- 7.2 mV, 12.8 +/- 7.8 mV, 13.6 +/- 9.4 mV (p > 0.05) and 10.5 +/- 5.5 mV, 10.9 +/- 6.7 mV, 10.4 +/- 5.5 mV (p > 0.05) respectively. In addition, PS and recommendation about the Autocapture remained unchanged during the study. In conclusion, MST, different body positions and exercise do not have any clinically important influence on the Autocapture function in children.

The results of electrophysiological study and radio-frequency catheter ablation in pediatric patients with tachyarrhythmia

A total of 135 consecutive pediatric patients (pts) with tachyarrhythmia ranging from two to 21 years of age (median age 11 years) underwent electrophysiological study (EPS) between January 1994 and July 2001. Tachycardia could not be induced in 38 of 135 pts (28%) and studies in these patients were accepted as the normal EPS. Supraventricular tachyarrhythmia mechanisms were atrioventricular (AV) accessory pathways in 47 patients (manifest accessory pathways in 23 patients, concealed accessory pathways in 17 patients, permanent junctional reciprocating tachycardia in 7 patients), re-entry without accessory pathway in 26 patients (AV nodal reentry tachycardia in 20 patients, atrial flutter in 5 patients, sinus node re-entry tachycardia in 1 patient) and atrial ectopic tachycardia in eight patients. The diagnosis of ventricular tachycardia (VT) was made in 16 patients. Seventy-three of the 97 patients with the diagnosis of tachyarrhythmia as a result of EPS underwent radiofrequency (RF) catheter ablation. The indications, early results, complications, safety and efficacy of RF catheter ablation were reviewed in these patients. Among the 73 patients who underwent RF ablation (85 procedures), the overall final success rate for all the diagnoses was 82% (60 of 73 patients). The median follow-up period for all patients was 16 months (range 2 to 60 months). Total recurrence rate in 73 patients was 4% (3 patients). Re-ablation was performed in only one of them and was successful. Procedure-related complications occurred in eight patients (11%): transient third-degree AV block in one patient, transient second-degree AV block in one patient, atrial flutter in two patients (1 needed direct current cardioversion), and atrial fibrillation in three patients (2 needed defibrillation and transient pacemaker implantation). In one patient with permanent third-degree AV block a transvenous pacemaker implantation was required. These midterm results suggest that RF catheter ablation has a good success rate and a low complication rate in pediatric patients, especially when it is carried out in experienced pediatric cardiology centers.

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.

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.

Stroke owing to noncompaction of myocardium

Noncompaction of myocardium is a rare and recently defined entity that may cause cardioembolism during childhood. We report an 18-month-old girl with noncompaction of the left ventricular myocardium presenting with fatal cardioembolic stroke. The patient had a high factor VIII level, which is known to cause an increased tendency to thromboembolic events. To our knowledge, this is the youngest case with stroke associated with noncompaction of the myocardium. Patients with noncompaction should be considered for prophylactic antithrombotic treatment to prevent mortality and morbidity owing to systemic thromboembolic events, especially if they carry additional risk factors that make them prone to hypercoagulation.

Thrombosis in children with cardiac pathology: frequency of factor V Leiden and prothrombin G20210A mutations

This study analyzed 28 thrombotic children with various cardiac disorders. They comprise 17% of a total of 168 patients with thrombosis from a single center. Among the 28 patients, 21 had congenital heart disease and 7 were diagnosed with cardiomyopathy. The patients with thrombosis were evaluated for congenital and acquired thrombotic risk factors. In addition to cardiac disorders, two, three, or more risk factors were present in 61% of the children with thrombosis. Two common mutations, namely factor V Leiden and prothrombin G20210A mutations, were found in 6 patients (22%). Nine patients (32%) died of infection, congenital heart disease, cardiomyopathy, thrombosis, operation, or a combination of these; two patients required surgical intervention. Following cardiac angiography, due to necrosis, amputation of the right index finger and right lower extremity was performed on 1 patient. The second patient's index fingers had to be amputated and resection of the bowel was performed following the operation on coarctation of the aorta. This study indicates that congenital heart disease and cardiomyopathy are two common cardiac disorders that may lead to the development of thrombosis. The majority of thrombosis develops within the heart and/or its great vessels. The second predominant site for thromboembolic symptoms is in the brain, including sinovenous thrombosis.

Unusual extraction of an active fixation ventricular pacing lead with outer coil fracture in a child

AIM

In this report we describe an asymptomatic paced child with outer coil fracture of the bipolar screw-in steroid eluting ventricular lead without insulation defect, loss of ventricular capture and unexpected increase in lead impedance in the bipolar VVIR pace configuration.

METHOD AND RESULT

A previously unpublished method was performed to retract the helix and the lead. As a result, the fractured lead was successfully retrieved.

CONCLUSION

We suggest that, this unusual extraction method can be tried as an alternative approach in the removal of an active fixation ventricular pacing lead with impaired mechanical function possibly due to fracture.

Spontaneous resolution of ventricular tachycardia with right bundle branch block morphology: a case report

Ventricular tachycardia is rare in children. In the absence of structural heart disease, ventricular tachycardia is known as idiopathic ventricular tachycardia and carries a good prognosis. We report a 14-month-old male child with right bundle branch block incessant ventricular tachycardia without structural heart disease. In this patient ventricular tachycardia was controlled by amiodarone and disappeared during follow-up. We want to stress the benign nature of this tachycardia if the previous treatment protocol had been appropriate.

Cardiac troponin T and myocardial injury during routine cardiac catheterisation in children

BACKGROUND

This study aims to investigate whether intracardiac catheterization produces myocardial damage on pediatric heart.

METHODS

Five blood samples were collected (basal, immediate post procedure, at 4, 12 and 24 h after the procedure) for troponin T and creatine kinase MB (CKMB) from 48 consecutive patients (age: 5.34+/-6.03 years). The effect of age, duration of procedure, pulmonary hypertension, cyanosis, and medication taken for congestive heart failure on the levels of troponin T and CKMB were sought.

RESULTS

The increase in CKMB (basal CKMB: 3.93+/-3.70 ng/ml; peak CKMB: 8.68+/-10.89 ng/ml; P<0.0001) and troponin levels (basal troponin: 0.002+/-0.003 ng/ml; peak troponin: 0.11+/-0.23 ng/ml; P<0.0001) over time was significant in the study group. Additionally younger patients (</=1 year), patients with pulmonary hypertension (mean pulmonary artery pressure >25 mmHg), longer procedure time (>30 min), and patients taking anti-congestive heart failure therapy had significantly higher levels of CKMB and troponin (P>0.05).

CONCLUSION

All patients undergoing cardiac catheterization are under risk of myocardial injury, and younger patients with pulmonary hypertension and especially with compensated cardiac failure have increased risk of myocardial damage, and need to be handled carefully.

Permanent transfemoral pacemaker implantation in a child with Maroteaux Lamy syndrome

Permanent transfemoral pacing has been described as an alternative route in patients in whom the superior venous approach is not feasible. This report describes the use of the femoral venous approach to insert a permanent pacemaker in a child with Maroteaux Lamy syndrome who has complete atrioventricular block and abnormal subclavian venous anatomy. Transfemoral pacing may be a suitable alternative in children with short stature.

Noncompaction of ventricular myocardium: a study of twelve patients

We report 12 patients with ventricular noncompaction who were echocardiographically identified at our institution since 1991. The mean age at presentation was 3.5 years. Five patients had isolated noncompaction. Three of them had subnormal left ventricular systolic function at presentation. Noncompaction was associated with complex congenital heart defect in 3 patients. Four patients had simple congenital heart defects: pulmonary stenosis, coarctation of aorta with aberrant origin of right subclavian artery, ventricular septal defect, and partial anomalous pulmonary venous return. The observed rhythm abnormalities were Wolff-Parkinson-White syndrome and paroxysmal supraventricular tachycardia, bigemini ventricular extrasystoles, and left bundle branch block. A transvenous pacemaker was implanted in a patient because of complete heart block. Noncompaction of the ventricular myocardium is rare. Our patients clearly represent the clinical and morphological spectrum of this disorder. Distinct morphological features can be diagnosed on 2-dimensional echocardiography.

Dual chamber cardiac pacing in children: Single chamber pacing dual chamber sensing cardiac pacemaker or dual chamber pacing and sensing cardiac pacemaker?

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. Twenty-eight 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.

Compatibility of automatic threshold tracking pacemakers with previously implanted pacing leads in children

The Autocapture function controls and optimizes the amplitude of the pacing pulse and saves energy. The manufacturer recommends using a special low polarization, low threshold bipolar Pacesetter lead for the Autocapture function. The purpose of this study was to evaluate the compatibility of Autocapture with previously implanted pacing leads. The study included 15 patients (mean age 13.6 +/- 3.4 years) who needed pulse generator replacement and received the VVIR pacemaker Regency SR+ or the DDDR pacemakers Affinity DR or Integrity DR with the Autocapture function. The new pulse generators connected to previously implanted ventricular leads. At the time of implantation the pacing threshold was 1.0 +/- 0.35 V at 0.5 ms, the lead impedance was 580 +/- 80 omega, and the spontaneous R wave amplitude was 7.89 +/- 4.89 mV. The polarization signal (PS) was 3.8 +/- 3.04 mV, and evoked response (ER) was 8.15 +/- 4.57 mV at the predischarge testing. Follow-up telemetry was done at months 1, 3, 6, 12, and 18. The follow-up duration was 9.4 +/- 5 months (range 1-18 months). If the results of PS and ER measurements were acceptable for autocapture, it turned on at the 1-month visit. In six (40%) patients the results were found acceptable for autocapture function. Age, lead impedance, pacing threshold, intrinsic R wave measurement, lead age, fixation mechanism, and ER measurements were not statistically different in Autocapture suitable and not suitable groups. The main reason not to activate Autocapture had been increased PS. Any significant fluctuations were not observed in pacing threshold, lead impedance, ER, and PS during follow-up. In conclusion, previously implanted pacing leads may be compatible with the Autocapture function.

Sinus node dysfunction in children and adolescents: treatment by implantation of a permanent pacemaker in 26 patients

Sinus node dysfunction has been reported rarely in pediatric patients with structurally normal hearts. It has been diagnosed with increasing frequency in children and young adult patients with congenital heart defect, especially in patients who have undergone corrective cardiac surgery related with atrial tissue. Between 1984-1999, 26 patients who were under 22 years of age underwent implantation of a permanent pacemaker for treatment of sinus node dysfunction at our medical center. This subset of patients represents 18.5% of all patients who required permanent pacemakers during this time. The mean age of the 17 male and 9 female patients at initial implantation was 9.2+/-6 years (range, 0.5 to 22 years). Of the 26 patients, 18 (69%) had associated cardiovascular disease and in 11 (34.6%) patients, sinus node dysfunction developed after a cardiac operation. The patients were followed up for a total 1,227 (47+/-45, range 2-176, median 34) pacing months. All symptomatic patients noted a resolution of symptoms after pacing had been performed, and they remained free of symptoms at the latest follow-up examination. Mean acute pacing thresholds and mean latest pacing thresholds for the endocardial atrial and ventricular leads, mean acute impedance and mean latest impedance for the endocardial atrial and ventricular leads and mean acute p wave voltage and the latest p wave voltage did not differ significantly. In this report, we review our experience in children who required implantation of a permanent pacemaker for treatment of sinus node dysfunction during a 15-year period.

Influence of D-net (EUROPEAN GSM-standard) cellular telephones on implanted pacemakers in children

This study was designed to evaluate possible interactions between digital cellular telephones and implanted pacemakers in children. The study comprised 95 patients (53 males and 42 females) with a mean age of 11.5 +/- 4.6 years (range 1-22 years). The average time from pacemaker implantation was 2.5 years (range 1 month-12 years). Fourteen (15%) devices were dual chamber and the remaining were single chamber pacemakers. The following companies manufactured the pacemakers tested: Medtronic (n = 42), Telectronics (n = 9), Vitatron (n = 16), Pacesetter (n = 19), CPI (n = 8), and Biotronik (n = 1). All the patients were tested in the supine position during continuous ECG monitoring. After completion of the routine pacemaker check, the effects of the European Global system for mobile communication (GSM) was tested using two cellular telephone models (Ericsson GA 628 and Siemens S 25, 2-W power). For this purpose, atrial and ventricular sensitivity settings were programmed to the most sensitive values, and the tests were carried out in the unipolar and bipolar sensing modes. The evaluation was performed during ringing, switching on/off, and conversation phase with the cellular telephone positioned over the pulse generator and around the pacemaker pocket. A malfunction of the pacemaker was not observed in any patient. Only 1 (1%) of 95 patients showed a brief oversensing problem during calls with the cellular telephone. In this case, an AAIR pacemaker was implanted transvenously in a subcutaneous pocket and the sensing defect occurred only with the unipolar sensing mode and was not reproducible. Once the source of interference was removed, no sensing defect was detected and the patient remained asymptomatic. No symptoms were experienced in this study. The authors believe that pacemaker dependent patients with nonprotected pulse generators manufactured at the beginning of 1990s may be tested by their physicians for possible interferences before they use a digital cellular telephone.

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

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.

RESULT

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.

Incidence of dysrhythmias in congenitally corrected transposition of the great arteries

We reviewed hospital records of 45 children with corrected transposition of the great arteries (c-TGA) to determine the incidence and outcome of congenital and postoperative dysrhythmias seen in this congenital anomaly. Our study comprised 45 patients (12 girls, 33 boys). The mean age of the patients at initial evaluation was 3.4 +/- 3.7 years, and they were followed for a mean period of 3.5 +/- 4 years. Forty-three patients (95%) with c-TGA had associated intracardiac defects. Two patients (5%) did not have any cardiac defects. In 31 (69%) of the 45 patients, ventricular septal defect (VSD) was present, while the remaining 14 patients (31%) had intact ventricular septum. VSD repair was done in 17 of 31 patients. Different types of dysrhythmias were detected in 19 of 45 patients. Six patients (13%) presented initially with congenital complete atrioventricular block (AVB) and five patients with postoperative complete ve AVB. Pacemaker implantation was required for 11 patients with complete AVB. In eight patients, ventricular and supraventricular ectopic beats, left bundle-branch block (LBBB) and first-degree AVB were determined but therapy was not required. TWenty-five (58%) of 43 patients with intracardiac defects underwent different surgical procedures. Permanent pacemaker implantation was required for five patients (29%) after VSD repair (17 patients) due to postoperative complete AVB. The incidence of congenital AVB in 14 patients with intact ventricular septum was found to be high (29%) in comparison to the group with VSD (6%). Patients diagnosed as c-TGA with or without cardiac defects should be followed carefully during their clinical course to identify and treat different types of dysrhythmias that can appear at any time.

Isolated noncompaction of the ventricular myocardium

Noncompaction of the ventricular myocardium is a rare congenital disorder characterized by the presence of numerous prominent trabeculations and deep intertrabecular recessess which communicate with the left ventricular cavity. The disease uniformly affects the left ventricle, and sometimes also affects the right ventricle. Echocardiographic findings are important clues for the diagnosis. Clinical symptoms include signs of left ventricular systolic dysfunction even to the point of heart failure, ventricular arrhythmias, and embolic events. We describe an illustrative case of isolated noncompaction of the left ventricular myocardium in a two-year-old child with the typical clinical and echocardiographic features of the disease. The literature on the topic is reviewed.

Complications and outcome in left-sided endocarditis in children

We retrospectively assessed the clinical course and outcome of left-sided endocarditis in pediatric patients to find out the prognostic significance of the presence and size of echocardiographically detected vegetations. Among the children admitted to our institution with endocarditis between January 1987 and October 1999, 16 patients (mean age 9.03 +/- 4.95 years) who met the Duke criteria for the diagnosis of infective endocarditis (IE) were included in this study. Rheumatic valvular disease was the most frequent underlying heart disease (10 patients: 62.5%). Five patients were operated at a mean of 13.9 months before endocarditis, and all had residual defects. Vegetation was detected in 11 cases (69%). Ten patients had major complications (within 2 weeks in 6 patients). Three patients developed congestive heart failure (CHF), six had intracranial and one had lower extremity emboli. Among them four were operated because of complications (CHF: 3 cases, intracranial emboli: 1 case). All the operated cases are doing well. The association between intracranial embolic events and echocardiographically detected vegetations was determined by calculating specificity (40%), sensitivity (100%), positive predictive value (50%), and negative predictive value (100%). No intracranial embolism occurred in patients without vegetations. All vegetations were < or = 6 mm in patients with systemic embolism. There were four deaths, three of which were because of intracranial embolism. This study suggests that intracranial emboli have a major risk of mortality in left-sided endocarditis. The larger size of the vegetation is not a predictor of complications; furthermore, the absence of vegetations predicts that the patient is safe from embolic events. Therefore all patients with left-sided IE should be considered for earlier surgical intervention.

Sotalol in treatment of pediatric cardiac arrhythmias

BACKGROUND

There is limited experience on sotalol use in the management of childhood arrhythmias. This study reviews the results of our experience with oral sotalol for treatment and prevention of tachyarrhythmias in children.

METHODS

The records of 62 patients (27 female, 35 male, mean age: 8.5+/-5.3 years) treated with sotalol for supraventricular or ventricular arrhythmias from 1994 to 1999 at our institution were reviewed. Demographic, clinical, echocardiographic, electrocardiographic (ECG), ambulatory ECG and electrophysiologic variables were collected.

RESULTS

Forty-two (63.6%) patients had re-entrant supraventricular tachycardia, eight patients (12.9%) had atrial tachycardia, one patient (1.6%) had junctional ectopic tachycardia, four patients (6.5%) had ventricular tachycardia, and seven patients (11.3%) had complex ventricular arrhythmias, as evidenced by surface or ambulatory ECG records; or revealed during the electrophysiological study. The mean sotalol dose was 3.9+/-1.2 mg/kg per day. In 15.5+/-13.9 months of sotalol use 50% (n=31) had complete relief of symptoms and/or arrhythmia and 29% (n=18) had partial relief. Sotalol was ineffective in 20% (n=13). Sotalol was more effective in re-entrant type supraventricular tachycardias (P=0.012). Sotalol was the first choice in 35.5% of patients. The sotalol therapy was initiated in inpatient settings in 40.3% (25 patients). Complications due to sotalol were seen in six patients (five patients developed bradycardia/pauses, and one patient had torsades de pointes) for which the sotalol dose was modified. In patients with sick sinus syndrome, a pacemaker was implanted and in another patient sotalol was stopped.

CONCLUSION

Sotalol, being an effective and safe drug particularly in children, is a good therapeutic alternative for the preventive treatment of childhood tachyarrhythmias.

A surgical approach on an emergency basis for removal of Wilms' tumor with intracardiac neoplastic extension

Extension of Wilms' tumor through inferior vena cava into the heart two years after the completion of therapy, is a very rare clinical aspect. We successfully operated on a 7 year old girl who had a huge right atrial mass which filled the right ventricle and right ventricular out flow tract, on an emergency basis using cardiopulmonary bypass.

A late complication with the CardioSEAL ASD occluder device and need for surgical revision

A late complication of the CardioSEAL atrial septal defect (ASD) occluder is reported. Although left atrial umbrella was completely epithelialized and occluded ASD without residual defect, the right atrial umbrella protruded toward the center of right atrium after 18 months. We believe this may be associated with the structural abnormality of the device.

Preliminary pediatric transesophageal echocardiography experiences

With transesophageal echocardiography (TEE), a new echocardiographic window is obtained which enables cardiologists to explore the heart from the esophagus and stomach. However, the procedure, when first undertaken, may present certain difficulties for the cardiologist in interpreting the anatomical findings and approaching a diagnosis. We thus convey our first experiences and results of TEE in 107 pediatric patients. Transesophageal echocardiography (TEE) was performed in 107 pediatric patients at our institution between December 1998-February 2001, using the standard techniques and following the standard criteria suggested by the American heart Association. The mean age of 54 male (50.5%) and 53 female (49.5%) patients was 7.8 years. Intubation difficulty was experienced in four cases. In one case, while drawing the transducer back from the esophagus, it kinked at the hypopharynx. None of the cases had major hemorrhage or esophageal rupture, and only a few cases had minor pharyngeal injuries or hemorrhages. We used TEE in detecting vegetations in patients with possible endocarditis, and evaluating the prosthetic valves and abnormal pulmonary venous return. We also used TEE to clarify preooperative anatomical details, postoperative complications and residual defects of complex congenital cardiac anomalies. Transcattheter closure of 47 secundum atrial septal defects (ASD)'s and a muscular ventricular septal defect (VSD) (both during patient selection and during the procedure) were accomplished under TEE guidance. As the pediatric cardiologists gain more experience in performing TEE, this technique will have a wider and more effective use in the pediatric population.

Anomalous origin of one pulmonary artery branch from ascending aorta ("so-called hemitruncus"): report of an additional case treated surgically

The aortic origin of one pulmonary artery branch, so-called hemitruncus, is a rare congenital anomaly with poor prognosis. In this report, an additional patient is presented. The patient, a 60-day-old male infant with the right pulmonary artery originating from the ascending aorta was operated successfully. Postoperative catheterization demonstrated normal flow to the right lung and pulmonary artery pressure decreased to normal level.

Isolated noncompaction of ventricular myocardium

Isolated noncompaction of the ventricular myocardium is a rare congenital cardiomyopathy resulting from an arrest in normal endomyocardial embryogenesis. The diagnosis can be made echocardiographically, and the entity may be associated with problems of cardiac rhythm. We describe two illustrative cases, with Wolf-Parkinson-White syndrome in one, and left bundle branch block in the other. We emphasize that children with problems of rhythm and findings suggestive for left ventricular cardiomyopathy, either hypertrophic or dilated; should be investigated to exclude isolated noncompaction of the ventricular myocardium.

The effect of recombinant human erythropoietin on serum selenium levels in hemodialysis patients

Succesful results in the treatment of anemia, one of the main complications of chronic renal failure, can be achieved by the use of recombinant human erythropoietin (RhEPO), which is available almost fifteen years in clinics. On the other hand, as both chronic renal failure and maintenance hemodialysis reduce the levels of trace elements, this study was designed to evaluate the interaction potential of RhEPO with serum concentrations of selenium (Se) during four months. Thirty one adult hemodialysis outpatients participated in the study. Ten of them, not on any drug therapy to interact with RhEPO, recruited as "Control Group", and the remainder, on RhEPO therapy, as "RhEPO Group". Blood was drawn from the Control Group at the beginning of the study, and from the RhEPO Group at every month for four months. Serum erythropoietin leveLs were measured by a radioimmunoassay method and Se status by a spectrofluorometric method. It was found that Se levels were not affected by RhEPO treatment during 3 months of therapy, while an increase was seen on the fourth month. The observation indicates that the increase in serum Se levels would be significant in longer than three-month RhEPO treatment.

Transcatheter closure of secundum atrial septal defects, a ventricular septal defect, and a patent arterial duct

We report our clinical experience with the newly developed Amplatzer device in transcatheter closure of nine atrial septal defects (ASDs), one ventricular septal defect (VSD), and one patent arterial duct (PDA). Eleven patients with ASD (age range 2.5-18 years) selected according to the location and size of the defect by transesophageal echocardiography (TEE), a five-year-old patient with muscular VSD and a one-year-old patient with PDA were considered for transcatheter closure with Amplatzer devices. All procedures were performed under general anesthesia with fluoroscopic and TEE guidance, following a routine hemodynamic evaluation in the catheter laboratory. The optimal device size was selected after the balloon sizing of the ASDs. The sizes of the VSD and PDA were measured on TEE and angiography. The patients were discharged at 24 hours, after an evaluation with x-ray, electrocardiogram (ECG), and echocardiography; they were on 3-5 mg/kg/day aspirin and infective endocarditis prophylaxis for six months after the procedure. They were reassessed at six to eight weeks and Holter monitoring was done in addition. Devices were used for nine ASD patients, and for the VSD and the PDA patients. Mean ASD size was 14.3 +/- 5.3 mm at TEE and 18.3 +/- 4.3 mm at balloon sizing (p=0.02). The mean size of the device was 18.7 +/- 4.2 mm. The procedure time and the fluoroscopy time were 46.1 +/- 12.3 and 12.9 +/- 1.6 minutes, respectively. Immediately after the procedure, four patients (44%) had trivial shunts (TS). TS remained in only two during discharge, and no shunt was observed at second evaluation. The devices were similarly applied to VSD (12-7 mm) and PDA (8-6 mm) patients. Both cases had TS immediately, which disappeared at 24 hours. None of the patients had major complications. Junctional rhythm developed in one patient, and another patient had frequent supraventricular extrasystoles. Amplatzer is an effective and safe device for transcatheter closure of ASD, VSD, or PDA, especially in pediatric patients.

Endovascular stent implantation in congenital heart defects

We report the immediate and short-term results of endovascular stent implantations from our center. We performed stent implantations in four patients (3, 12, 18 and 20 years old) with different stenoses or obstructions: right ventricular outflow conduit obstruction, left Blalock-Taussig obstruction, post-operative recoarctation and cavopulmonary anastomosis obstruction. Stent were implanted successfully. The mean diameters of stenoses were expanded from 4.5 +/- 3.5 (2-7) mm to 9 +/- 1. 2 (8-10) mm, and the complaints of patients were improved significantly by stent implantation. There was no complication related to the procedures. All patients are living except one who died from cerebrovascular event unrelated to the stent implantation. The mean follow-up period of three living patients is 6.3 +/- 5.5 (1-2) months. As of the last control, all have remained at the caliber achieved at original placement. In light of our limited experience and previous reported studies, we conclude that intravascular stents are safe and can be used effectively in selected patients with congenital heart defects.

Congenital sick sinus syndrome with breath holding and severe syncope episodes during infancy. A case report

Sick sinus syndrome is a rare cause of bradycardia in children without structural heart disease. A case of profound sinus bradycardia, sinus arrest with junctional escape, and pauses in a two-year-old infant with breath-holding and syncope episodes is presented. As a result of these clinical symptoms and electrocardiographic findings, the patient with sick sinus syndrome underwent implantation of transvenous ventricular pacemaker. He has been well and asymptomatic since the insertion of the pacemaker. In the differential diagnosis of an infant with breath-holding and syncope episodes, when these symptoms in particular cannot be explained by other common reasons, sick sinus syndrome should be kept in mind. This case also illustrates the importance of electrocardiographic studies for the diagnosis.

Dilatation of a restrictive interatrial communication using a balloon angioplasty catheter

Balloon atrioseptostomy is a life-saving procedure palliating certain congenital heart defects like transposition of the great arteries, right or left atrioventricular valve atresia, hypoplastic left heart syndrome, and pulmonary hypertension. Occasionally the Rashkind balloon septostomy technique may be ineffective in creating an adequate interatrial communication. We performed balloon dilatation of a restricted atrial septal defect using a balloon angioplasty catheter in a three-month-old infant.

Analysis of 2017 Holter records in pediatric patients

Holter monitoring (HM) is widely used in arrhythmic disorders of adult patients; however, studies in the pediatric age group are limited. This study aims to determine the value of HM in diagnosis and treatment of disorders related to arrhythmias in pediatric patients. We examined 2,017 Holter records of 1,500 children who applied to our institution between November 1994 and October 1998. The age ranged from 0-24 years (52% male, 48% female). The indications for HM were screening for arrhythmic symptoms (palpitation, chest pain, syncope) in 67 percent, monitoring dysrhythmic therapy in 17 percent, postoperative control in five percent, and pacemaker control in four percent. Palpitation is the leading presenting symptom, with more frequent findings of supraventricular extrasystole (SVE), supraventricular tachycardia (SVT), ventricular extrasystole (VE) and complete heart block (CHB) when compared to other symptoms. Only 5.3 percent of the patients had arrhythmic symptoms during monitoring and asymptomatic patients had more frequent arrhythmias. SVT, VE, and CHB are more frequent findings in the abnormal heart with previous cardiac operations. The diagnostic yield is low with arrhythmic symptoms in the pediatric age group; however, HM enables cumulative evaluation of heart rhythm and rhythm variability, which is important in diagnosing silent arrhythmias in high risk groups (abnormal heart, postoperative heart).