Cardiac Arrhythmias In Children Research Articles

Patient management exchange: Cardiac arrhythmias in children

J Pediatr Health Care. (2000). 14, 127–129.

The Hemodynamic and Holter-Electrocardiogram Changes During Halothane and Sevoflurane Anesthesia for Adenoidectomy in Children Aged One to Three Years

The Hemodynamic and Holter-Electrocardiogram Changes During Halothane and Sevoflurane Anesthesia for Adenoidectomy in Children Aged One to Three Years

Cardiac arrhythmias in children during outpatient general anaesthesia for dentistry: a prospective randomised trial

Deaths in children associated with outpatient general dental anaesthesia may be attributable to sudden cardiovascular collapse precipitated by ventricular arrhythmias. A causal link between halothane anaesthesia, ventricular arrhythmias, and deaths has been suggested. We did a prospective, randomised trial to investigate the frequency and character of arrhythmias during anaesthesia with halothane and the alternative anaesthetic agent, sevoflurane. 150 children, aged 3-15 years, who needed dental extraction under general anaesthesia were randomly assigned sevoflurane or halothane supplementation of 66% nitrous oxide in oxygen with spontaneous ventilation. The halothane group (n=50) received halothane introduced in 0.75% increments, every two to three breaths, to a maximum of 3.0%, with maintenance at 1.5%. The incremental sevoflurane group (n=50) received sevoflurane introduced in 2% increments increased to a maximum of 8%, with maintenance at 4%. The 8% sevoflurane group (n=50) received sevoflurane introduced at 8%, with maintenance at 4%. 24 (48%) children receiving halothane had arrhythmias compared with four (8%) receiving incremental sevoflurane (difference 40% [95% Ci for differences 24-56] p<0.0001), and eight (16%) receiving 8% sevoflurane (difference 32% [15-50] p=0.0013). Halothane-associated arrhythmias occurred during dental extraction or emergence and were mainly ventricular. Six (12%) children in the halothane group had ventricular tachycardia. The methods of sevoflurane administration did not differ significantly for the frequency of arrhythmias (p=0.357). Sevoflurane-associated arrhythmias were mainly single supraventricular ectopic beats. There was a strong association between halothane and ventricular arrhythmias, especially ventricular tachycardia. The use of sevoflurane in preference to halothane could contribute to a decline in morbidity and mortality associated with dental anaesthesia.

Ambulatory electrocardiographic methods for the evaluation of cardiac arrhythmias in children

Une équipe mobile d’intervention en psychiatrie a été mise en place en Meurthe-et-Moselle. Elle a pour but de permettre le maintien au domicile de patients psychotiques. Par leur travail de stimulation et d’étayage psycho-affectif, les aides-soignantes apportent un soutien afin que les patients puissent mieux vivre avec leur pathologie.

Primary cardiac arrhythmias in children.

Primary cardiac arrhythmias are much less common in children than adults. This study was performed to identify the characteristics of primary arrhythmias in pediatric patients in the Emergency Department (ED). Retrospective review of ED visits of patients <18 years of age presenting between January 1991 and November 1996 with an Emergency Department diagnosis of primary cardiac arrhythmia. Secondary cardiac arrhythmias, ie, sinus tachycardia resulting from a fever, were excluded. Clinically significant arrhythmias were defined as those capable of altering cardiovascular stability. SITE: 26 Community Hospital EDs. A total of 2.3 million ED visits were reviewed and 320 arrhythmias in children were identified in 0.58 million patients under 18 years of age. The overall incidence of arrhythmias was 13.9 per 100,000 ED visits and 55.1 per 100,000 pediatric ED visits. The incidence of clinically significant arrhythmias was 5.7 per 100,000 ED visits and 22.5 per 100,000 patients <18 years of age. The mean patient age was 113 (+/-0.31) years with a peak in infancy and a second peak in late childhood and adolescence. The most common arrhythmias were: Sinus tachycardia: 160 (50%); Supraventricular tachycardia (SVT): 42 (13%); Nonspecific arrhythmia (NSA): 34 (10.6%); Bradycardia: 19 (6%); and Atrial fibrillation (a-fib): 15 (4.6%). The most common clinically significant arrhythmias by age group were: [table in text]. Nine patients had an additional diagnosis of Wolf-Parkinson-White syndrome, eight with Sinus tachycardia and one with SVT. There were four cardiac arrests noted all with ventricular fibrillation as the recorded arrhythmia. Primary arrhythmias are unusual ED presentations in children and atrial tachyarrhythmias are the most common rate and rhythm disturbance in this population.

Recognition and management of childhood cardiac arrhythmias.

Cardiac arrhythmias are common in children, but most of them are benign and do not signify underlying heart disease. However, the main tachyarrhythmias (SVT and VT) can cause cardiovascular collapse, and should therefore be treated promptly. Drug treatment is generally effective and is appropriate in stable patients. DC shock is the treatment of choice in patients with compromised circulation. There is a wide array of antiarrhythmic drugs and though they are generally safe, most of them have the potential for serious adverse effects. Hence, there is a need to exercise caution and balanced judgement in prescribing them. It is perhaps best for the general duty paediatric staff to be familiar with a select few, and stick to them if possible. Management of most cases of cardiac arrhythmia in children is within the competence of non-cardiologist paediatric staff. But in some instances cardiology referral will be required, either for further investigations, for decision regarding longterm drug therapy, or for more technical management modalities.

The relationship between temperature and calcium in acute cell damage after exposure to radiofrequency or thermal energy in isolated neonatal and adult rabbit cardiac myocytes.

Radiofrequency (RF) ablation is a nonsurgical technique using catheter-directed RF energy for treating cardiac arrhythmias in children and adults. Previous reports have suggested that sequestration of calcium (Ca2+) by the sarcoplasmic reticulum may partially protect mature cardiac myocytes from the effects of RF energy. The purposes of this study were to determine whether differences exist between neonatal and adult myocyte responses to RF energy and if myocyte damage is a Ca2+-dependent process. Because immature myocardium is functionally deficient in sarcoplasmic reticulum, we hypothesized that immature myocytes would be more susceptible to damage induced by RF energy. Isolated ventricular myocytes were obtained from neonatal and adult New Zealand White rabbits by enzymatic dissociation, then placed in a perfusion chamber designed to deliver RF energy or a heated perfusate solution. Measurements of bath temperature, cell morphology, and contractile response to electrical stimuli were recorded. RF energy application associated with increased perfusate temperature resulted in cell death, but not when the temperature rise was inhibited. Thus, the acute damage to cells exposed to RF energy appears to be mediated by thermal energy. After exposure to thermal energy, neonatal cells underwent contracture at lower temperatures than did adult cells. Perfusion with solutions containing low Ca2+ concentrations, comparable to intracellular diastolic Ca2+ levels, had a protective effect for both neonatal and adult myocytes. These findings indicate that acute cell damage after exposure to RF energy is mediated by a Ca2+-dependent process. Furthermore, immature myocardium is particularly susceptible to RF-mediated cell damage, possibly secondary to reduced Ca2+ sequestration by the sarcoplasmic reticulum.

Low birth weight and risk of cardiac arrhythmias in children

Low birth weight and risk of cardiac arrhythmias in children

Low Birth Weight and Risk of Cardiac Arrhythmias in Children

This study aimed to investigate a possible association between low birth weight (LBW) and other perinatal major characteristics and the risk of a child having accessory pathways of conduction tissue and cardiac arrhythmia later in life. Thirty-one children aged 1-15 years (12 boys, 19 girls), in whom the persistence of accessory pathways of conduction tissue in the heart and inducible reciprocating supraventricular tachycardia were confirmed by means of programmable transoesophageal pacing, constituted the study group. None of them exhibited signs of either inborn or acquired heart disease causing arrhythmia, and their parents and siblings did not suffer cardiac arrhythmias. The control group was formed of 62 apparently healthy children (two controls for each case) matched to cases for sex, age, date and place of birth. Information on infant perinatal and maternal characteristics was collected retrospectively. High risk of arrhythmia in children was associated with LBW (< 2500 g): odds ratio was equal to 14.6 (95% CI: 1.7-127.9; P = 0.015), and it remained after adjustment had been made for major potential confounders. In addition, children with arrhythmia were more often born with retarded intrauterine growth (birth weight < 10 percentile), preterm (< 37 weeks of gestation), of higher birth order, and had lower Apgar scores at 1 and 5 min. Their mothers more often had diagnosed gynaecological diseases. Antenatal stress leading to LBW may be associated with atypical development and maturation of cardiac conduction system and increased risk of cardiac arrhythmias later in life.

Radiofrequency Catheter Ablation for Cardiac Arrhythmias in Children

Radiofrequency Catheter Ablation for Cardiac Arrhythmias in Children

Pediatric cardiovascular intensive care: Arrhythmia management

Cardiac arrhythmias in children in the pediatric cardiovascular intensive care unit are a function of the interaction between the intrinsic disease, complications of successful palliation and treatment, and the moment-to-moment homeostatic state of the patient (autonomic tone, electrolyte balance, hemodynamic status, therapeutic agents). Knowledge regarding all three factors are critical for the successful management of arrhythmias in patients in the pediatric cardiovascular intensive care unit. Continuous electrocardiographic monitoring with an archival system is essential for instantaneous and accurate detection of potentially life-threatening tachy and bradyarrhythmias. Intensivists, cardiologists and intensive care nursing personnel must constantly process data that lead to rapid diagnosis and definitive management of an abnormal cardiac rhythm in these highly vulnerable children.

Amphotericin B Overdose in Pediatric Patients with Associated Cardiac Arrest

To report the first five cases of amphotericin B overdose with secondary cardiac complications in a pediatric population. Treatment is also presented. Hospital. Two infants and three children inpatients receiving amphotericin B. Cardiac complications were observed in five pediatric patients who received between 4.6 and 40.8 mg/kg/d of amphotericin B. Cardiac arrest occurred in all patients, and four patients died. A detailed description of the cardiac event is provided for one patient who was on a cardiac monitor during the adverse reaction. Hydrocortisone prophylaxis and verapamil therapy were the primary therapies used in patient 1 (the only survivor). Evaluation of the literature provides substantial evidence for the use of hydrocortisone in prevention of cardiac arrhythmias. Amphotericin B overdose can be fatal in children and infants. The presentation in humans appears similar to that in dogs where cardiac arrhythmias occurred at doses of 5-15 mg/kg. Hydrocortisone may decrease the incidence of mortality associated with cardiac arrhythmias in children receiving amphotericin B overdoses. Animal studies are necessary to evaluate this observation and potential disadvantages of hydrocortisone usage.

Oxygen desaturation and cardiac arrhythmias in children during esophagogastroduodenoscopy using conscious sedation.

To determine whether oxygen desaturation and cardiac arrhythmias occur in children during esophagogastroduodenoscopy with the use of conscious sedation, we prospectively studied 34 consecutive patients between the ages of 2 months and 18 years. Patients with pulmonary, cardiac, and neurologic disorders were defined as high risk and those without were defined as normal. All patients received intravenous sedation with meperidine, diazepam, or midazolam, used alone or in combination. Pulse oximetry, respiratory rate, and lead II electrocardiogram were recorded throughout all episodes of desaturation and tachycardia. Oxygen desaturation to less than 90% occurred in 68% of normal patients and in 58% of high-risk patients during esophagogastroduodenoscopy. Seventy-five percent of the high-risk patients and 82% of the normal patients had an arrhythmia during esophagogastroduodenoscopy usually associated with oxygen desaturation. Sinus tachycardia was the most common arrhythmia, although other arrhythmias were identified. Despite the frequency of oxygen desaturation and cardiac arrhythmias, no adverse outcome was observed in any patient. Most episodes of oxygen desaturation and cardiac arrhythmia resolved spontaneously. Subdivision of patients into high-risk groups by age, sex, weight, or diameter of endoscope used did not allow prediction of oxygen desaturation or cardiac arrhythmia. Our data suggest that conscious sedation in children undergoing esophagogastroduodenoscopy is safe and free of significant adverse clinical problems. However, conscious sedation during esophagogastroduodenoscopy continues to have certain inherent risks. Therefore we strongly advocate the routine use of continuous cardiac rhythm and pulse oximetry monitoring of all children during esophagogastroduodenoscopy performed with the use of conscious sedation.

Experience with flecainide for the treatment of cardiac arrhythmias in children.

We treated 22 children, aged 3 days to 16 years 6 months (median 11 years 1 month), with flecainide for a variety of arrhythmias where a Class I agent was indicated. In 16, conventional antiarrhythmic treatment had failed. Structural heart disease was present in nine. The arrhythmia was paroxysmal re-entry atrioventricular tachycardia in nine; paroxysmal atrial tachycardia, flutter or fibrillation in five; paroxysmal ventricular tachycardia in five and frequent ventricular extrasystoles (with couplets) in three. Sinus rhythm was achieved in all four children who received flecainide during tachycardia (three received intravenous flecainide, one oral). During follow-up of 3-24 months (median 12 months), arrhythmia control was obtained in 13 children (59%). Combination therapy was used in seven of these; with digoxin in four and a beta blocker in three. Flecainide doses used in this study ranged from 1-11 mg kg-1 day-1 (median 4 mg kg-1 day-1), 25-297 mg m-2 day-1 (median 113 mg m-2 day-1). The median, pre-dose flecainide concentration in those responding to therapy was 225 micrograms l-1 and in those failing to respond was 417 micrograms l-1. An arrhythmogenic effect occurred in one child.

Surgical treatment of pediatric cardiac arrhythmia

The combination of improved diagnostic techniques, new and potent antiarrhythmia agents, and progress in antiarrhythmia surgical procedures has resulted in successful management of complex cardiac arrhythmia in children. The kinds of arrhythmia that can be considered for possible surgical intervention share several features. Each produces symptoms and usually is hemodynamically compromising. Each requires extensive preoperative and intraoperative electrophysiologic evaluation to establish the mechanism, response to drugs, and suitability for surgery. Although reports of surgical arrhythmia treatment have been limited in children, with increasing success the indications for such treatment may become less stringent. Our recommendations are shown in the Table. In general, patients intolerant of or unresponsive to medical treatment for symptomatic arrhythmia (tachycardia or bradycardia), should be considered candidates for surgical antiarrhythmia procedures. These patients should be referred for testing to cardiac centers staffed by pediatric cardiac electrophysiologists and surgeons experienced in arrhythmia diagnosis and ablation. Careful evaluation can identify those patients in whom surgical approaches are most appropriate. At present, surgical operations for selected, serious pediatric cardiac arrhythmias offer definitive and possibly curative treatment, and may be preferable to inadequate, poorly tolerated, or long-term medical therapy.

Medicolegal Problems in the Management of Cardiac Arrhythmias in Children

Malpractice actions against pediatricians treating patients with arrhythmias have been recurrent in four general areas. Optimal medical management may not be widely recognized. Cases illustrating the following concepts are presented. Intravenous verapamil therapy in babies may cause apnea, hypotension, and bradycardia; continued episodes of atrial flutter in a child may cause sudden death; quinidine may be related to the death; children with "familial seizure disorders" may in fact have the long QT interval syndrome. The QT interval must be measured on the ECG in patients with unexplained seizures; "supraventricular tachycardia with aberration" is uncommon in children. Rapid heart rates with QRS complexes that are different from the sinus complexes are likely to be ventricular tachycardia. These situations must be recognized as potential problems and must be treated appropriately.

Advances in the Management of Cardiac Arrhythmias in Children

The authors discuss several recent developments in the diagnosis and management of cardiac arrhythmias in the young, focusing on areas in which the greatest progress has been made so that the pediatrician can incorporate these developments into his practice and participate more fully in the management of the patient requiring tertiary care.

Cardiac arrhythmias in children.

Recent interest in cardiac arrhythmias in children has been stimulated by a growing awareness of primary rhythm disorders in children, by the appearance of rhythm disorders following repair of many congenital heart defects, and by recent developments in clinical electrophysiology. This chapter focuses on developmental clinical cardiac electrophysiology, the spectrum of tachycardias in children, and the frequency, mechanism, and therapeutic decisions regarding cardiac arrhythmias in children who have had surgery for congenital heart disease.

Amiodarone in the treatment of cardiac arrhythmias in children: One hundred thirty-five cases

Oral amiodarone was given to 135 children (mean age, 10.2 years) for a mean duration of 4.1 months (range, 1 day to 6 years) for mainly idiopathic (25%) and postoperative (61%) arrhythmias. Complete ECG control or partial ECG control with clinical improvement was obtained in 60% and 33% of cases, respectively, regardless of the arrhythmia location (atrial 69%, junctional 16%, and ventricular 15%), mechanism, resistance (55%) or sensitivity (45%) to other drugs, and presence of cardiomegaly (40%) or clinical signs of heart failure (27%). The only factor favoring improvement was a short history (< 2 months in 54%). The rapid onset of drug effect (4.1 days), the early relapses after treatment discontinuation (3.3 weeks), and the absence of side effects due to drug accumulation reflect a faster metabolism than that in adults, with no cardiac toxicity and a low incidence of thyroid dysfunction (2 hyperthyroid, 1 hypothyroid).

Kinetics of digoxin absorption and relation of serum levels to cardiac arrhythmias in children.

The effect of route of administration on the uptake and elimination of digoxin and the relationship of serum digoxin levels to cardiac arrhythmias was investigated in 15 children with congenital cardiac defects who were receiving maintenance doses of digoxin. The highest serum digoxin concentrations were noted 1 hour after oral and parenteral administration. This probably does not represent the peak levels achieved with the parenteral routes since that first samples were taken 1 hour after the digoxin. The magnitude of the (steady state) serum digoxin concentration and the level obtained at 1 hour were dose‐related. Group 1 subjects (half‐daily maintenance dose: 0.005 ± 0.0015 mg per kilogram) had a steady‐state serum concentration of 0.98 ± 0.41 ng per milliliter 12 hours after the last maintenance dose and a level of 1.8 ± 0.6 ng per milliliter 1 hour after the test dose. In contrast, Group II subjects (half‐daily maintenance dose: 0.011 ± 0.002 mg per kilogram orally) had a 12 hour steady‐state serum concentration of 2.54 ± 0.35 ng per milliliter and a 1 hour peak of 5.1 ± 0.49 ng per milliliter that were both apprOXimately two and one‐half times as great as those occurring in Group 1. Parenteral administration of digoxin intramuscularly and intravenously in doses eqUivalent to those used in Group II subjects produced serum concentrations that were of the same magnitude. In the limited number of patients there was no apparent relationship between the serum digoxin level and the onset or persistence of cardiac arrhythmias.