digoxin and Wolff-Parkinson-White-Syndrome

The optimal management of atrial fibrillation is of considerable clinical importance, and with the recent publication of four studies suggesting the equivalence of rate and rhythm control strategies, new attention has been focused on rate control. Reasons for rate control include reduction of symptoms and the prevention of tachycardia-mediated cardiomyopathy; yet, evidence-based definitions of optimal rate control are lacking. This article examines an approach to rate control that includes serial assessment of heart rate and symptoms, both at rest and with exertion, and the use of therapy tailored to the individual and modified over time (as no single therapy demonstrates clear superiority). Often, multidrug regimens including digoxin and a calcium channel blocker or beta-blocker are required, and in a minority of patients atrioventricular nodal ablation and pacing are necessary. Several novel therapies currently under development are also discussed.

Topics: Adrenergic beta-Antagonists; Anti-Arrhythmia Agents; Atrial Fibrillation; Calcium Channel Blockers; Digoxin; Heart Conduction System; Heart Rate; Humans; Wolff-Parkinson-White Syndrome

To review the literature regarding the use of antiarrhythmic agents in the management of Wolff-Parkinson-White (WPW) syndrome and atrioventricular nodal reentry tachycardia (AVNRT) in infants and children, and to discuss the advantages and disadvantages of specific agents in each arrhythmia in an effort to develop treatment guidelines.. A MEDLINE search encompassing the years 1966-1996 was used to identify pertinent literature for discussion. Additional references were found in the articles that were retrieved via MEDLINE.. Clinical trials that address the use of antiarrhythmic agents for the treatment of the supraventricular tachycardias WPW and AVNRT in children were selected. Literature pertaining to dosage, pharmacokinetics, efficacy and toxicity of antiarrhythmic agents in children were considered for possible inclusion in the review, and information judged to be pertinent by the authors was included in the discussion.. Although there are numerous reports of antiarrhythmic use in children, very few large studies are designed to evaluate an individual antiarrhythmic agent for a specific arrhythmia. Controlled, comparison trials of antiarrhythmic agents in children are virtually nonexistent. Ideally, controlled clinical trials are used to develop clinical guidelines; however, in this situation, most data and information must be obtained from case series of children treated. Although the results from these type of studies may be useful in developing guidelines for the optimal use of these agents, controlled trials are required for establishing standard treatment guidelines for all patients.. Despite limited scientific evaluation of conventional agents in the treatment of WPW and AVNRT in children, they continue to be used as standard of care. Most information regarding the use of conventional agents in children has been extrapolated from the adult literature. Little justification for the use of agents or dosing in children is available. Controlled trials regarding the use of new antiarrhythmic agents (propafenone, amiodarone, flecainide) are available; however, the variance in dosing schemes, presence of structural heart disease, and patient age make the development of recommendations difficult.. Because of greater clinical experience with these conventional antiarrhythmic agents, they continue to be first-line therapy in the management of most supraventricular tachycardia (SVT) in children. The management of SVT in children with WPW syndrome should begin with the use of a beta-blocker with the addition of digoxin or procainamide for treatment failures. The use of digoxin monotherapy, although frequently used by many practitioners in infants and children with WPW, cannot be recommended. For failures to conventional agents, flecainide is the preferred agent, while therapy with propafenone, amiodarone, and sotalol remains to be elucidated. The management of AVRNT is similar to that of WPW; however, digoxin is the agent of first choice. Trials of beta-blockers and procainamide should follow for treatment failures with flecainide again being the preferred "newer" antiarrhythmic for use in resistant cases. Additional well-designed, controlled trials are needed to further evaluate the comparative efficacy of antiarrhythmics in the management of WPW and AVNRT in children, as well as to evaluate dosing and toxicity in various age groups.

Topics: Adrenergic beta-Antagonists; Amiodarone; Anti-Arrhythmia Agents; Calcium Channel Blockers; Child; Child, Preschool; Digoxin; Flecainide; Humans; Infant; Propafenone; Sotalol; Tachycardia, Atrioventricular Nodal Reentry; Wolff-Parkinson-White Syndrome

Atrial fibrillation (AF) with rapid ventricular response is a common tachyarrhythmia requiring hospitalization. The increased morbidity and mortality due to the hemodynamic consequences of acute AF is well recognized. Management strategies may be formed based on the evaluation of the entire clinical context including cardiovascular status and the associated noncardiac clinical disorders. Intravenous (i.v.) beta blockers and calcium channel blockers are equally effective in rapidly controlling the ventricular rate in acute AF in selected individuals. The addition of digoxin to the regimen causes a favorable outcome. However, digoxin as a single agent is generally inefficacious in slowing the ventricular rate in acute AF. These standard pharmacotherapies however, are contraindicated in ventricular preexcitation syndrome associated with rapid ventricular rate due to AF. In this situation the drug of choice is i.v. procainamide. When clinical condition is unstable or hemodynamically compromised, cardioversion is the treatment of choice in all cases of AF with rapid ventricular rate. Radiofrequency ablation of the AV node or anomalous tract may be considered in refractory or high risk subjects as a last resort.

Topics: Anti-Arrhythmia Agents; Atrial Fibrillation; Digoxin; Diltiazem; Heart Rate; Humans; Propranolol; Verapamil; Wolff-Parkinson-White Syndrome

Topics: Action Potentials; Administration, Oral; Atrial Fibrillation; Atrioventricular Node; Autonomic Nervous System; Digitalis Glycosides; Digoxin; Drug Interactions; Exercise Test; Heart Failure; Verapamil; Wolff-Parkinson-White Syndrome

Topics: Arrhythmias, Cardiac; Bradycardia; Cardiac Complexes, Premature; Child; Child, Preschool; Deafness; Digoxin; Electric Countershock; Electrocardiography; Female; Heart Failure; Heart Ventricles; Humans; Infant; Infant, Newborn; Lidocaine; Male; Propranolol; Tachycardia; Ventricular Fibrillation; Wolff-Parkinson-White Syndrome

Topics: Action Potentials; Cardiac Complexes, Premature; Digoxin; Electrocardiography; Heart; Heart Atria; Heart Conduction System; Heart Ventricles; Humans; Neural Pathways; Pacemaker, Artificial; Procainamide; Prognosis; Quinidine; Sinoatrial Node; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Little is presently known regarding whether a rhythm-control or a rate-control strategy is more frequently used in patients hospitalized for atrial fibrillation (AF). This study was conducted to assess patient and physician characteristics associated with each treatment strategy and with the use of anticoagulants. Hospitalizations for primary diagnoses of AF were examined using hospital claims from January 2000 to December 2004. Patients who received antiarrhythmic drugs, ablation, or cardioversion for AF were categorized as receiving rhythm control. Patients managed only with beta blockers, calcium channel blockers, or digoxin were categorized as receiving rate control. Characteristics associated with rhythm compared with rate control and anticoagulant use with CHADS(2) score were determined. The study cohort included 155,731 hospitalizations from 464 hospitals. Of these, 75,397 (48%) were categorized as involving rhythm control and 80,334 (52%) as involving rate control. Care by a noncardiologist (adjusted odds ratio [OR] 0.33, 95% confidence interval [CI] 0.31 to 0.36) and increasing age >65 years (adjusted OR 0.87, 95% CI 0.86 to 0.88) were associated with lower odds of rhythm versus rate control; hypertrophic cardiomyopathy was associated with greater odds (adjusted OR 2.3, 95% CI 1.81 to 2.84) of rhythm control. Warfarin use was greater in the rhythm-control group compared with the rate-control group (adjusted OR 1.56, 95% CI 1.52 to 1.60), and warfarin use was greater with a CHADS(2) score > or =2 (unadjusted OR 1.21, 95% CI 1.19 to 1.24). In conclusion, rhythm- and rate-control strategies were used equally in patients hospitalized for AF. Some observations, such as greater use of the rate-control strategy with increasing age, were consistent with recommendations, but others, such as lower use of warfarin in the rate-control group, were not.

Topics: Adrenergic beta-Antagonists; Age Factors; Aged; Aged, 80 and over; Anti-Arrhythmia Agents; Anticoagulants; Aspirin; Atrial Fibrillation; Calcium Channel Blockers; Cardiomyopathy, Hypertrophic; Catheter Ablation; Digoxin; Drug Utilization; Electric Countershock; Female; Hospitalization; Humans; Male; Medicine; Middle Aged; Myocardial Infarction; Platelet Aggregation Inhibitors; Retrospective Studies; Severity of Illness Index; Specialization; United States; Warfarin; Wolff-Parkinson-White Syndrome

We surveyed Accident and Emergency (A&E) consultants in England by questionnaire, on their management of patients presenting with AF. Completed questionnaires were received from 124 (45%). Most (42%) would use digoxin as first-line treatment for rate control of AF; 28% would not treat AF acutely but would refer the patient to the medical team; 59% would cardiovert a patient with AF in A&E, if there was evidence of cardiovascular compromise. Some 51% would not routinely initiate any anticoagulation therapy. Faced with a patient in fast AF who was haemodynamically unstable, 67% would immediately opt for electrical cardioversion, 13% would refer the patient directly to the medics and 15% would initially treat with intravenous digoxin. Given a patient in fast AF and cardiac failure, 55% would treat with digoxin. Asked about AF related to Wolff-Parkinson-White syndrome, 37% would initially give adenosine, 23% would opt for immediate DC cardioversion and 25% would refer directly to the medics; however, a minority would still give a rate-limiting calcium antagonist or digoxin. The majority (79%) would not treat AF in a known alcoholic with acute intoxication who was haemodynamically stable. Consultants were more likely to initiate treatment if the patient had signs of shock or heart failure. Where there were underlying medical problems they were more likely to refer the patient directly to the medical team. There was a general reluctance to initiate anticoagulation, and some difference in opinion over how long AF should have persisted for anticoagulation to be necessary in the context of electrical cardioversion. Given the current evolution of A&E as an acute speciality, A&E clinicians should at least initiate management of patients with AF and be prepared to care for them for some time in A&E.

Topics: Alcoholism; Anticoagulants; Atrial Fibrillation; Cardiotonic Agents; Digoxin; Electric Countershock; Emergency Service, Hospital; England; Health Care Surveys; Heart Failure; Humans; Practice Patterns, Physicians'; Referral and Consultation; Surveys and Questionnaires; Thyroid Diseases; Wolff-Parkinson-White Syndrome

Re-entrant supraventricular tachycardia is the most common cardiac arrhythmia in infancy. Pharmacological prevention of recurrencies is a standard recommendation for infants less than 1 year of age. In view of the often benign spontaneous clinical course of the disease, the risk-benefit analysis of any antiarrhythmic agent given is important. It was the aim of this retrospective study, to assess the value of oral long-term digoxin given to paediatric patients with supraventricular tachycardia with onset in the first 4 months of life. Twenty-six newborns and infants fulfilled the inclusion criteria. Median age at first presentation of the patients was 7 days. Eight patients (31%) had structural heart disease, 9 patients had a pre-excitation syndrome, and the other 17 children had a concealed accessory atrioventricular pathway. Long-term prophylaxis with oral digoxin was considered successful in 17 children (65%). In 2 patients therapy with digoxin was considered partially effective and in 7 patients (27%) failure of digoxin to improve symptoms led to the introduction of other anti-arrhythmic agents. Serum digoxin levels were no different in the patients with successful therapy as compared to those with treatment failure. No side-effects due to digoxin were noted in all the patients treated. After a mean followup of 54 months (12-130 months), 19 children (73%) were free of recurrencies and on no medication, 5 children were free of recurrencies but had anti-arrhythmic therapy. Only 2 patients, both on anti-arrhythmic therapy, were still suffering from tachycardia.. Digoxin remains an effective treatment option in infants with supraventricular tachycardia and it helped to avoid the long-term use of other anti-arrhythmic drugs with potentially more serious side-effects (pro-arrhythmia) in a considerable proportion of infants treated.

Topics: Anti-Arrhythmia Agents; Digoxin; Female; Heart Defects, Congenital; Humans; Infant; Infant, Newborn; Male; Recurrence; Retrospective Studies; Tachycardia, Atrioventricular Nodal Reentry; Treatment Outcome; Wolff-Parkinson-White Syndrome

Topics: Anti-Arrhythmia Agents; Digoxin; Electrocardiography; Esophagus; Follow-Up Studies; Humans; Infant, Newborn; Predictive Value of Tests; Propranolol; Prospective Studies; Recurrence; Risk; Tachycardia, Supraventricular; Wolff-Parkinson-White Syndrome

Topics: Adenosine; Anti-Arrhythmia Agents; Cardiovascular Agents; Contraindications; Digoxin; Drug Interactions; Humans; Infant, Newborn; Tachycardia, Supraventricular; Ventricular Fibrillation; Wolff-Parkinson-White Syndrome

A previously healthy and normally developing 12-day-old female suddenly became restless and developed cold sweats, tachypnoea and tachycardia (300 beats/min). Neither electrocardiogram nor echocardiogram showed evidence of any cardiac defect. Carotid sinus massage and other vagus-stimulating manoeuvres, undertaken because paroxysmal supraventricular tachycardia (PSVT) was suspected, were unsuccessful. Before rapid digitalization, adenosine triphosphate was administered (0.1 mg/kg intravenously). Sinus rhythm was restored within about 60 s. Despite further treatment with digoxin and verapamil (4 mg/kg.d), further episodes of PSVT occurred, each again responding to ATP (0.1 to 0.3 mg/kg). There were no side effects. After 24-hour Holter ECG monitoring had revealed Wolff-Parkinson-White syndrome as cause of the PSVT, propafenone was administered (15 mg/kg daily) and has prevented further recurrence of the tachycardia.

Topics: Adenosine Triphosphate; Digoxin; Drug Therapy, Combination; Echocardiography; Electrocardiography; Electrocardiography, Ambulatory; Female; Humans; Infant, Newborn; Propafenone; Tachycardia, Supraventricular; Verapamil; Wolff-Parkinson-White Syndrome

Topics: Adenosine; Adult; Digoxin; Female; Fetal Diseases; Flecainide; Heart Rate, Fetal; Humans; Infant, Newborn; Male; Pregnancy; Tachycardia, Supraventricular; Wolff-Parkinson-White Syndrome

We present a case of persistent fetal supraventricular tachycardia where transplacental and direct fetal treatment with amiodarone caused an iatrogenic hypothyroidism. This condition was successfully managed with the intra-amniotic instillation of 250 micrograms of L-thyroxine weekly, for 3 weeks. A male infant was delivered at 32 weeks by Caesarean section. The neonatal electrocardiogram showed Wolf-Parkinson-White (WPW) syndrome, which was controlled by digoxin alone. Thyroid function normalized quickly and the baby is developing normally.

Topics: Adult; Amiodarone; Digoxin; Female; Fetal Diseases; Humans; Hypothyroidism; Infant, Newborn; Male; Pregnancy; Tachycardia, Supraventricular; Thyroxine; Wolff-Parkinson-White Syndrome

In patients with Wolff-Parkinson-White syndrome and atrial fibrillation, digoxin may increase the ventricular rate by facilitating conduction over the accessory pathway either directly by enhancing accessory pathway conduction and/or indirectly as a consequence of its effect on atrioventricular nodal conduction. Two cases are presented in which the intravenous administration of magnesium sulfate reversed digoxin facilitation of the ventricular rate to atrial fibrillation in the Wolff-Parkinson-White syndrome.

Topics: Aged; Atrial Fibrillation; Digoxin; Electrocardiography; Female; Heart Rate; Heart Ventricles; Humans; Magnesium Sulfate; Male; Middle Aged; Wolff-Parkinson-White Syndrome

A complication of transesophageal atrial pacing in an infant with Wolff-Parkinson-White syndrome (WPW) is reported. A newborn infant born with fetal hydrops had recurrent supraventricular tachycardia (SVT) that required repeated successful conversion by transesophageal atrial pacing. Because of secondary left ventricular dysfunction, digoxin was administered. During repeat transesophageal atrial pacing for recurrent SVT, ventricular fibrillation occurred. Although it is unclear which of several possible contributing factors was responsible for the ventricular fibrillation, recommendations are appropriate to minimize the risk in infants with WPW.

Topics: Cardiac Pacing, Artificial; Digoxin; Esophagus; Female; Humans; Infant, Newborn; Recurrence; Tachycardia, Supraventricular; Ventricular Fibrillation; Wolff-Parkinson-White Syndrome

Seventy consecutive patients hospitalized before 1 year of age for reentrant paroxysmal atrial tachycardia (PAT) were studied according to the age of onset of arrhythmia making 3 distinctive groups: group I: 10 patients in whom onset of the arrhythmia occurred during foetal life; group II: 39 infants whose arrhythmia appeared during the first month of life and group III consisting of 21 patients in whom tachycardia began between 1 and 12 months of age. The characteristics and the consequences of the arrhythmia as well as the patients' course and the different treatments used were analysed. Foetal tachycardias were characterized by a slower heart rate. Episodes were most often short and repetitive as opposed to post-natal tachycardias which were often prolonged but somewhat unfrequent. Before the age of 3 months the occurrence of heart failure was more frequent. Independently of the age of onset, 43% of patients presented Wolff-Parkinson-White syndrome (WPW), which disappeared spontaneously in 1 out of 3 cases. The existence of WPW syndrome was correlated with late relapses.

Topics: Age Factors; Digoxin; Female; Heart Defects, Congenital; Heart Failure; Humans; Infant; Infant, Newborn; Male; Pregnancy; Prenatal Diagnosis; Tachycardia, Paroxysmal; Time Factors; Wolff-Parkinson-White Syndrome

Drug efficacy and pharmacokinetics were assessed in 63 patients, aged 5 days to 30 years (mean 8 years), who received flecainide acetate for control of resistant arrhythmias. Doses of flecainide ranged from 59 to 225 mg/m2 body surface area per day (mean 141) in divided doses every 8 to 12 h and serum trough levels ranged from 0.10 to 0.99 micrograms/ml (mean 0.36). Flecainide controlled or partially controlled arrhythmia in 53 (84%) of the 63 patients: 7 of 7 patients who had the permanent form of junctional reciprocating tachycardia, 12 of 13 who had an atrial ectopic tachycardia, 10 of 10 who had ventricular tachycardia and 18 of 25 patients who had reentrant supraventricular tachycardia. Five of seven patients who had the latter arrhythmia were unsuccessfully treated with flecainide. They had Wolff-Parkinson-White syndrome and developed asymptomatic, incessant, slower orthodromic reciprocating tachycardia while receiving the drug. Transient blurred vision was reported in three patients and two patients had transient hyperactivity. No significant hemodynamic side effects were seen in any patient. Twenty-five patients underwent oral pharmacokinetic investigation. Young infants (less than 1 year of age) had a mean plasma elimination half-life (t 1/2) approximating that (11 to 12 h) found in older children and healthy adults; children aged 1 to 12 years had a shorter mean t 1/2 of 8 h. Dosing schedules based on milligrams per square meter body surface area correlated better with plasma flecainide levels than did dosing based on milligrams per kilogram body weight.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Administration, Oral; Adolescent; Adult; Arrhythmias, Cardiac; Child; Child, Preschool; Digoxin; Echocardiography; Electrocardiography; Flecainide; Follow-Up Studies; Half-Life; Humans; Infant; Tachycardia; Wolff-Parkinson-White Syndrome

Electrophysiologic properties of the accessory pathway were investigated before and after the intravenous administration of digoxin (0.01-0.02 mg/kg) during electrophysiologic studies in 14 infants and children with the Wolff-Parkinson-White syndrome. Determination of electrophysiologic properties of the accessory pathway was made using transesophageal atrial pacing and/or intracardiac right atrial pacing. Maximal effect on the accessory pathway after intravenous digoxin was observed during one to six hours. Effective refractory period of the accessory pathway increased in 6 of the 14 patients, decreased in 4 and unchanged in 4. Shortest AP 1:1 conduction increased in 5 of the 12 patients, decreased in 3 and unchanged in 4. Tachycardia was not induced after digoxin in only one patient. Tachycardia cycle length, ventriculoatrial conduction time and atrioventricular conduction time were unchanged after digoxin in almost all cases. Thus, digoxin is not the first choice drug for termination and prevention of the preexcitation syndrome.

Topics: Adolescent; Age Factors; Cardiac Pacing, Artificial; Child; Child, Preschool; Digoxin; Electrophysiology; Female; Humans; Infant; Injections, Intravenous; Male; Wolff-Parkinson-White Syndrome

The records of 90 patients with Wolff-Parkinson-White syndrome who presented with supraventricular tachycardia in the first 4 months of life were reviewed. Among these, 63% were male. Structural heart disease was present in 20%, most commonly Ebstein's anomaly. All patients presented with a regular narrow QRS tachycardia, and pre-excitation became evident only when normal sinus rhythm was established. Only one infant had atrial flutter and none had atrial fibrillation. Type A Wolff-Parkinson-White syndrome was most common (49%), with heart disease occurring in only 5% of these patients. In contrast, heart disease was identified in 45% of those with type B syndrome. Initially, normal sinus rhythm was achieved in 88% of the 66 infants treated with digoxin with no deaths. Normal sinus rhythm resumed after electrical countershock in 87% of the 15 infants so treated. Maintenance digoxin therapy was used in 85 patients. The Wolff-Parkinson-White pattern disappeared in 36% of the patients. Four infants died of cardiac causes during the mean follow-up period of 6.5 years. Two of these four infants had congenital heart disease; the third, with a normal heart initially, developed ventricular fibrillation and died from a cardiomyopathy considered related to resuscitation. The remaining infant, with a normal heart, died suddenly at 1 month of age. All were receiving digoxin. A wide QRS tachycardia later appeared in three patients, all with heart disease, one of whom died.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Combined Modality Therapy; Digoxin; Ebstein Anomaly; Electric Countershock; Electrophysiology; Female; Follow-Up Studies; Heart Conduction System; Humans; Infant; Infant, Newborn; Male; Recurrence; Sinoatrial Node; Tachycardia; Wolff-Parkinson-White Syndrome

Topics: Atrial Fibrillation; Atrial Flutter; Digoxin; Edrophonium; Electric Countershock; Emergencies; Humans; Pressure; Propranolol; Tachycardia, Paroxysmal; Verapamil; Wolff-Parkinson-White Syndrome

Topics: Aged; Atrial Fibrillation; Bufanolides; Digoxin; Electrocardiography; Humans; Lown-Ganong-Levine Syndrome; Male; Proscillaridin; Wolff-Parkinson-White Syndrome

Digoxin has been successfully used to treat fetal supraventricular tachycardia. When therapy with digoxin fails, alternative therapies have met with equivocal success. In this report, successful fetal therapy with maternally administered digoxin and quinidine is presented in three consecutive patients with fetal supraventricular tachycardia. The arrhythmia was eliminated in each instance. Fetal ascites, present in two fetuses, was completely reversed. Intrapartum fetal distress was not observed. The rationale of this therapy and a review of pertinent literature are also presented.

Topics: Administration, Oral; Adolescent; Adult; Ascites; Digoxin; Drug Therapy, Combination; Echocardiography; Female; Fetal Diseases; Humans; Pregnancy; Quinidine; Tachycardia; Wolff-Parkinson-White Syndrome

In a cooperative, retrospective, study 120 children are reviewed with preexcitation pattern. 80 patients had tachycardias; 54 children were under 1 year, 49 under 3 months of age at their first attack. In 50% the preexcitation pattern disappeared in the first year of life, allthough intermittent preexcitation could be seen in some patients. In 12 patients a circusmovement tachycardia was proved on the surface ecg; in the group of 63 children with a tachycardia of unknown origin probably more may be caused by this mechanism. A beneficial effect of digoxin in childhood is noticed, with good response in 45 cases. A possible explanation for the difference in effect of digoxin during childhood and in adolescence is discussed.

Topics: Adolescent; Age Factors; Child; Child, Preschool; Digoxin; Electrocardiography; Heart Defects, Congenital; Humans; Infant; Infant, Newborn; Retrospective Studies; Tachycardia; Wolff-Parkinson-White Syndrome

Ten patients with refractory recurrent supraventricular tachycardia were found by electrophysiologic study to have bypass tracts and orthodromic atrioventricular reentrant tachycardia. All had failed to respond to conventional antiarrhythmic therapy and were therefore treated with oral amiodarone (1,600 to 2,000 mg/day for 2 weeks, then 800 to 1,200 mg/day for another 2 weeks with subsequent 200 to 600 mg/day maintenance doses). During or after the fourth week of therapy, electrophysiologic study was repeated. In 9 of 10 patients, supraventricular tachycardia could not be reinduced by programmed stimulation. In the remaining patient, nonsustained supraventricular tachycardia (greater than 10 beats, lasting less than 30 seconds) with a slower basic cycle length than that during the control period was provoked. Significant increases in the effective refractory period of the accessory pathway in both the anterograde (+26%, p less than 0.05) and retrograde (+40%, p less than 0.02) directions were noted, the magnitude of change being independent of the control effective refractory period. There were also significant increases in the effective refractory period of the right atrium (+24%, p less than 0.01) and the right ventricle (+15%, p less than 0.01) during long-term therapy with amiodarone. Over a mean follow-up period of 20 months, symptomatic control of the arrhythmia occurred in all patients; in only one patient treatment with amiodarone could not be continued because of side effects. These data establish the electrophysiologic basis for the effectiveness of amiodarone in the prophylactic control of refractory paroxysmal supraventricular tachycardia complicating the bypass tract syndromes.

Topics: Adult; Aged; Amiodarone; Benzofurans; Digoxin; Electrocardiography; Heart Conduction System; Humans; Male; Middle Aged; Propranolol; Tachycardia; Wolff-Parkinson-White Syndrome

Clinical and electrocardiographic findings for 30 patients with the pre-excitation syndrome are described together with details of treatment. Nineteen (63%) were younger than 2 years, 14 of whom were under 2 months. Sixteen infants and 7 children (77%) presented with paroxysmal supraventricular tachycardia, 14 (61%) of whom had the electrocardiographic pattern of type A Wolff-Parkinson-White (WPW) syndrome. During paroxysmal bouts the QRS complex was normal in 21 patients and wide in two. Six (20%) patients had congenital heart disease often associated with WPW syndrome type B. Seventeen patients were treated with either digoxin or verapamil intravenously to stop tachyarrhythmias. Verapamil was more effective due to the immediate response and lack of adverse effects. The tachyarrhythmias resolved in all the patients and in some of them the WPW pattern resolved later indicating maturation of the conduction tissue with loss of the accessory pathways. Verapamil provides a rapid and safe form of treatment for conversion of tachyarrhythmias since it has no effect on the accessory pathways. Oral amiodarone prevents recurrent tachyarrhythmias resistant to other treatment.

Topics: Adolescent; Amiodarone; Child; Child, Preschool; Digoxin; Electrocardiography; Humans; Infant; Infant, Newborn; Tachycardia, Paroxysmal; Verapamil; Wolff-Parkinson-White Syndrome

Topics: Atrial Fibrillation; Digoxin; Drug Interactions; Heart Ventricles; Humans; Kinetics; Verapamil; Wolff-Parkinson-White Syndrome

In 22 patients with atrioventricular reentrant tachycardia incorporating a retrogradely conducting accessory pathway, electrophysiologic studies were done before and after oral digoxin, 1.25 mg, and propranolol, 160 to 240 mg, each given in 4 divided doses at 6-hour intervals. Before digoxin and propranolol, all 22 patients had induction of sustained tachycardia. After the medication six patients lost the ability to induce atrial echo and one lost the ability to sustain tachycardia due to an increased retrograde accessory pathway or atrial refractoriness or both. Six patients lost the ability to induce or sustain tachycardia due to increased atrioventricular nodal refractoriness. In the remaining nine patients with inducible sustained tachycardia, cycle lengths of tachycardia were prolonged. These findings suggest that combined use of oral digoxin and propranolol is useful in selected patients with atrioventricular reentrant tachycardia.

Topics: Adolescent; Adult; Aged; Digoxin; Drug Therapy, Combination; Female; Heart Conduction System; Heart Function Tests; Humans; Male; Middle Aged; Propranolol; Tachycardia; Wolff-Parkinson-White Syndrome

Topics: Digoxin; Female; Humans; Infant, Newborn; Ovum; Ventricular Fibrillation; Wolff-Parkinson-White Syndrome

We reviewed the records of 217 children whose first episode of supraventricular tachycardia occurred before 18 years (median age 24 months). There were 112 males and 105 females. Of the 49 with congenital heart disease, SVT began before any operation in 26 and greater than 2 weeks postoperatively in 23. Wolf-Parkinson-White syndrome was present on surface ECG in 47/217 (22%). Congestive heart failure accompanied the first episode of SVT in 38% of the patients who were 4 months of age or younger, and in only 19% of those over 4 months (P less than 0.001). Treatment was successful in stopping SVT within 48 hours in 90/142 (63%). Successful short-term treatment included digoxin 57/184 (68%), cardioversion 12/20 (60%), vagal maneuvers 12/19 (63%), phenylephrine 3/9, and overdrive pacing 4/5. SVT recurred at least once in 83% of all patients. On follow-up (mean 4.6 years), episodes of SVT were still present in 56%. Three patients died--two from incessant SVT and one from a CVA after VSD repair. We conclude that long-term status was difficult to predict, but SVT was present in fewer patients whose age at onset was less than 4 months and in those with unoperated CHD. Early recurrence was not a poor prognostic sign. We recommended treatment for at least one year in all patients with SVT, whether or not the first episode terminates spontaneously.

Topics: Adolescent; Anti-Arrhythmia Agents; Child; Child, Preschool; Digoxin; Female; Follow-Up Studies; Heart Failure; Humans; Infant; Infant, Newborn; Male; Tachycardia; Wolff-Parkinson-White Syndrome

The digitalis derivative beta-methyldigoxin has been shown to be quickly and well absorbed from the gut and, in hemodynamic studies, to start acting rapidly after intravenous administration. However, when tested on 6 patients suffering from paroxysmal reciprocating atrioventricular tachycardia, or having an accessory pathway who might develop this disorder, there was no effect on induced tachycardias or on AV conduction during rapid atrial pacing or the extrastimulus test. One of the 6 patients showed some increase in refractoriness of conduction through the AV node within 25 min after the injection. Beta-methyldigoxin does not appear to be a satisfactory alternative to other effective agents available for the prompt correction of paroxysmal reciprocating atrioventricular tachycardia.

Topics: Adolescent; Adult; Cardiac Pacing, Artificial; Digoxin; Electrocardiography; Electrophysiology; Heart Conduction System; Humans; Male; Medigoxin; Middle Aged; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

A 66-year-old white woman with a greater than 20-year history of electrocardiographic evidence of the Wolff-Parkinson-White syndrome, including documented recurrent supraventricular tachycardias, was studied. Despite the disappearance of the delta wave after initiation of therapy with digoxin and quinidine sulfate, the patient continued to have frequent episodes of supraventricular tachycardia. At a time when the serum levels of digoxin and quinidine were in the therapeutic range, extensive electrophysiologic studies were performed. Supraventricular tachycardia at a rate of 160 beats per minute was initiated by induced atrial premature depolarizations. The circuit of tachycardia involved anterograde conduction through the pathway of the atrioventricular node and His bundle and retrograde conduction through the bypass tract. We concluded that elimination of the delta wave and other electrocardiographic characteristics of the Wolff-Parkinson-White syndrome cannot be relied upon to indicate successful pharmacologic prophylaxis for induction of tachyarrhythmia associated with this syndrome.

Topics: Aged; Atrioventricular Node; Bundle of His; Cardiac Pacing, Artificial; Digoxin; Electrocardiography; Female; Humans; Quinidine; Tachycardia; Wolff-Parkinson-White Syndrome

23 cases of paroxysmal tachycardia in infancy and childhood (22 cases of supraventricular and 1 case of ventricular paroxysmal tachycardia) are reported. Clinical problems of 13 infants aged 1 day to 6 months are compared with those of 10 children and discussed. A primary disease e.g. congenital heart disease, myocarditis was observed in 8 cases and WPW-syndrome in 4 cases. Owing to the threatening cardiac failure especially in infancy a special attention should be taken to the immediately diagnosis. Treatment and prevention are discussed.

Topics: Child; Child, Preschool; Digoxin; Electrocardiography; Female; Follow-Up Studies; Humans; Infant; Infant, Newborn; Infant, Newborn, Diseases; Male; Radiography; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Adult; Atrial Fibrillation; Digoxin; Disopyramide; Humans; Male; Organophosphorus Compounds; Refractory Period, Electrophysiological; Wolff-Parkinson-White Syndrome

The effect of digitalis in 21 patients with Wolff-Parkinson-White syndrome was anlayzed with respect to the ventricular response during atrial fibrillation and antegrade and retrograde refractory periods of accessory pathways. Digitalis shortened the cycle length of the most rapid ventricular response (shortest R-R) (i.e., increased the ventricle response) in 6/21 patients, increased the cycle length in 7/21 patients, had no effect on the cycle length in 5/21, and could not be determined in 3/21. Digitalis could be directly related to the onset of ventricle fibrillation resulting from atrial fibrillation in 9/21 patients. Each of these patients had shortest R-R intervals (220 msec or less) during atrial fibrillation in the control data. The results of this study indicate that no a priori prediction about the effect of digitalis on the antegrade conduction of accessory pathways can be made. By elective induction of atrial fibrillation it is possible to separate WPW patients into groups at high and low risk for developing ventricular fibrillation with the administration of digitalis.

Topics: Adolescent; Adult; Aged; Atrial Fibrillation; Digoxin; Electrocardiography; Female; Heart Ventricles; Humans; Male; Middle Aged; Wolff-Parkinson-White Syndrome

A case of atrioventricular reciprocal rhythm and chronic reciprocating tachycardia in a newborn infant is presented. Electrophysiological studies suggest that these rhythm disturbances are related to the presence of a right-sided atrioventricular accessory pathway capable only of retrograde conduction (concealed Wolff-Parkinson-White syndrome). The technique of recording the sequence of atrial activation during the tachycardia is described and its clinical importance emphasised.

Topics: Cardiac Catheterization; Digoxin; Electrophysiology; Heart Block; Heart Conduction System; Humans; Infant, Newborn; Infant, Newborn, Diseases; Male; Propranolol; Tachycardia; Wolff-Parkinson-White Syndrome

Topics: Digoxin; Humans; Methods; Procainamide; Propranolol; Quinidine; Secologanin Tryptamine Alkaloids; Wolff-Parkinson-White Syndrome

Patient-controlled rapid atrial pacing was used to manage 12 cases of recurrent supraventricular tachycardia refractory to drug therapy. The pacing system consists of an implanted receiver-lead system and an external patient-activated transmitter. In each case, brief periods (5 to 20 seconds) of rapid atrial pacing were effective in terminating the supraventricular tachycardia and resulted in a return to normal sinus rhythm. In three patients, occasional transient episodes of atrial flutter or atrial fibrillation preceded a spontaneous return to normal sinus rhythm. The pacing system was removed in one patient 13 months postoperatively because of persistent pericarditis; one patient died of an unrelated cerebral hemorrhage 13 months postoperatively. Successful management of supraventricular tachycardia has been maintained in the 10 remaining patients for 15 to 36 months (average 26.4). In more than 6,000 patient applications of rapid atrial pacing, there has been only one failure to convert the tachycardia. Successful application of permanent rapid atrial pacing requires (1) prescreening of patients with temporary external rapid atrial pacing to verify susceptibility to conversion of supraventricular tachycardia and absence of anomalous conduction pathways that may permit conduction of rapid pacing rates to the ventricles, and (2) assessment of the patient's ability to use the transmitter properly.

Topics: Adult; Aged; Atrial Fibrillation; Digoxin; Heart Rate; Humans; Male; Middle Aged; Pacemaker, Artificial; Procainamide; Propranolol; Recurrence; Self-Help Devices; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Atrial Fibrillation; Atrial Flutter; Atrioventricular Node; Child; Congenital Abnormalities; Delivery, Obstetric; Digoxin; Electrocardiography; Female; Heart Failure; Humans; Infant; Infant, Newborn; Male; Pregnancy; Propranolol; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Adolescent; Adult; Aged; Arrhythmias, Cardiac; Blood Pressure; Bradycardia; Digoxin; Electrocardiography; Female; Heart Ventricles; Humans; Injections, Intravenous; Male; Methyldopa; Middle Aged; Syndrome; Tachycardia; Tachycardia, Paroxysmal; Verapamil; Wolff-Parkinson-White Syndrome

Topics: Arrhythmia, Sinus; Arrhythmias, Cardiac; Coronary Disease; Digoxin; Diuretics; Electroconvulsive Therapy; Endocarditis, Bacterial; Heart Aneurysm; Heart Failure; Heart Valve Diseases; Heart Ventricles; Humans; Lidocaine; Myocardial Infarction; Pacemaker, Artificial; Pericarditis, Constrictive; Potassium Deficiency; Rupture; Spironolactone; Tachycardia; Ventricular Fibrillation; Wolff-Parkinson-White Syndrome

Topics: Adult; Aged; Bundle of His; Bundle-Branch Block; Digoxin; Electrocardiography; Female; Heart Block; Heart Conduction System; Humans; Male; Middle Aged; Sinoatrial Node; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Aged; Atrial Fibrillation; Digoxin; Electrocardiography; Hemodynamics; Humans; Lidocaine; Male; Practolol; Procainamide; Ventricular Fibrillation; Wolff-Parkinson-White Syndrome

Topics: Ajmaline; Apgar Score; Arrhythmias, Cardiac; Cesarean Section; Digoxin; Electrocardiography; Extraction, Obstetrical; Female; Fetus; Heart Block; Humans; Infant; Infant, Newborn; Lanatosides; Pregnancy; Prenatal Diagnosis; Tachycardia; Tachycardia, Paroxysmal; Ventricular Fibrillation; Verapamil; Wolff-Parkinson-White Syndrome

Topics: Adolescent; Adult; Arrhythmias, Cardiac; Atrial Fibrillation; Cardiac Catheterization; Digoxin; Electrocardiography; Female; Heart Rate; Humans; Male; Methods; Middle Aged; Phenytoin; Procainamide; Propranolol; Quinidine; Tachycardia, Paroxysmal; Time Factors; Wolff-Parkinson-White Syndrome

Topics: Adolescent; Age Factors; Child; Child, Preschool; Digoxin; Electrocardiography; Female; Heart Defects, Congenital; Heart Ventricles; Humans; Infant; Infant, Newborn; Infections; Male; Methods; Myocarditis; Quinidine; Sulfates; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Ajmaline; Digoxin; Electrocardiography; Furosemide; Humans; Infant, Newborn; Infant, Newborn, Diseases; Male; Phytotherapy; Plants, Medicinal; Potassium; Rauwolfia; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Arrhythmias, Cardiac; Digoxin; Electrocardiography; Heart Conduction System; Heart Failure; Humans; Male; Middle Aged; Mitral Valve Stenosis; Propranolol; Wolff-Parkinson-White Syndrome

Topics: Aged; Diagnosis, Differential; Digoxin; Electrocardiography; Female; Humans; Metaraminol; Tachycardia; Wolff-Parkinson-White Syndrome

Topics: Animals; Arrhythmias, Cardiac; Digoxin; Dogs; Female; Male; Phenytoin; Wolff-Parkinson-White Syndrome

Topics: Digoxin; Electric Countershock; Humans; Intestinal Obstruction; Male; Middle Aged; Postoperative Complications; Potassium Chloride; Quinidine; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Digoxin; Drug Therapy; Electrocardiography; Heart Block; Heart Conduction System; Humans; Myocardial Infarction; Quinidine; Reserpine; Tachycardia; Tachycardia, Paroxysmal; Wolff-Parkinson-White Syndrome

Topics: Atrial Fibrillation; Diagnosis, Differential; Digoxin; Electrocardiography; Humans; Procainamide; Prognosis; Quinidine; Tachycardia; Tachycardia, Ventricular; Wolff-Parkinson-White Syndrome