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Query: UMLS:C0018799 (heart disease)
 34,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The natural history of patients with asymptomatic prolonged ventricular pauses and the indications for permanent pacing are controversial. To examine this problem, 6,470 consecutive 24-hour Holter recordings were reviewed between 1979 and 1983 for the presence of ventricular pauses of at least 3 seconds. Fifty-two patients (0.8% of total), 22 men and 30 women, were identified with an average longest pause duration of 4.1 seconds. Holter recordings were requested to evaluate syncope in 14 patients (27%), dizziness in 9 (17%) and other reasons in 29 (56%). Causes of the pauses were sinus arrest in 22 patients, atrial fibrillation with slow ventricular response in 18 patients and atrioventricular block in 12. Holter recordings were also evaluated for the presence of tachyarrhythmias. Six patients had nonsustained ventricular tachycardia and 7 had supraventricular tachycardia. Five of the 52 patients (10%) had dizziness or syncope during pauses. Twenty-six patients (50%) received permanent pacemakers. The paced (26 patients) and unpaced (26 patients) groups were similar in the length and etiology of pause, associated tachyarrhythmias, presence of bradycardia-related symptoms, prevalence of organic heart disease, medications and length of follow-up. Four patients in the paced group and 2 in the unpaced group died, yielding 3-year actuarial survival probabilities of 78% and 85%, respectively. It is concluded that ventricular pauses of 3 seconds or longer are uncommon, these pauses usually do not cause symptoms, and the presence of these pauses does not necessarily portend a poor prognosis or the need for pacing in asymptomatic patients.
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PMID:Significance of ventricular pauses of three seconds or more detected on twenty-four-hour Holter recordings. 398 58

Associated electrophysiologic abnormalities and site of delay were studied in 20 patients, aged 1.5 to 16.5 years, with congenital heart disease and first-degree atrioventricular (AV) block (PR interval above the 98th percentile for age and heart rate). Eight of the 20 patients with first-degree AV block were studied after 1 or more cardiovascular operations. Refractory periods of the atrium, AV node, His-Purkinje system and ventricle were determined. As a further test for AV nodal integrity, rapid atrial pacing was performed and the cycle at which Wenckebach periodicity occurred was noted. Four groups were identified. Group I included 4 patients (20%) with intraatrial conduction delay (long PA interval). Three patients had depressed sinus nodal function and 1 had depressed AV nodal function. Group II included 7 patients (35%) with AV nodal delay (long AH interval). One patient had sinus nodal depression and 2 had AV nodal depression (prolonged AV nodal refractory period or Wenckebach at a long paced cycle length). Group III included 3 patients (15%) with His-Purkinje delay (long HV interval). Measured functions were normal in all patients. Group IV included 6 patients (30%) with normal or high normal intracardiac intervals with long PR. One patient had sinus nodal dysfunction, 2 patients had long atrial refractory periods, 1 had AV nodal depression; 2 had long refractory period of the His-Purkinje system, and 1 had long ventricular refractory period. Atrial flutter was induced in 1 patient.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Site of conduction delay and electrophysiologic significance of first-degree atrioventricular block in children with heart disease. 399 64

Echocardiographic evaluation of 42 patients with sarcoidosis disclosed 13 patients (group A) with abnormalities compatible with sarcoid heart involvement such as thickening or thinning of the septum (eight patients), pericardial effusion (four patients), and increased end-diastolic dimension of the left ventricle with decreased systolic function (three patients). The remaining 29 patients (group B) were diagnosed as having normal echocardiograms. The clinical data revealed no statistically significant difference between the groups regarding age, sex, chest x-ray stage, activity, and previous heart disease. Group A patients had older clinical onset of the disease (52 vs 83 months; p less than 0.05) and higher incidence of ECG abnormalities than group B patients. There were no statistically significant differences between the groups regarding two-dimensional echocardiographic internal dimensions of both ventricular chambers. The radionuclear right ventricular ejection fraction was low in both groups and the left ventricular ejection fraction was depressed in group A patients (p less than 0.01). As observed in pathologic studies, the septum is a target structure which can be characterized echocardiographically. Screening suspected sarcoid heart disease involvement is important to characterize patients with a relatively high risk of clinical cardiac abnormalities such as complete atrioventricular block, ventricular arrhythmias, congestive heart failure, and sudden death.
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PMID:Echocardiographic evaluation of patients with systemic sarcoidosis. 401 69

Three patients with dystrophia myotonica and echocardiographic signs of subclinical cardiopathy had cardiac side effects during oral treatment with phenytoin sodium or carbamazepine. These side effects were dose related: ventricular tachycardia appeared at a toxic serum phenytoin level in one patient and disappeared as the concentration fell within the therapeutic range, and atrioventricular block grade 1 developed in two patients at low serum carbamazepine levels, its severity increasing with the drug level. Given the risk of dangerous side effects, cardiac status needs to be carefully assessed before administration of phenytoin or carbamazepine in the treatment of dystrophia myotonica.
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PMID:Cardiac side effects of phenytoin and carbamazepine. A dose-related phenomenon? 405 36

Acute poisoning with beta adrenergic inhibitors is rare although such drugs are widely prescribed. Between 1966 and 1980, 40 cases were recorded at the Fernand-Widal Toxicology Center. 40% of patients were asymptomatic and 25% had sinus bradycardia. 35% of patients had specific toxic signs, either atrioventricular block (20%) or hemodynamic disorders (15%); the latter were seen only when associated heart disease was present or when another cardiotropic agent had been absorbed. No deaths were recorded. This favorable prognosis may result from the self-limited nature of poisoning with beta blocking agents, myocardial function being similar to that which follows denervation. In severe cases, management includes pacing and glucagon.
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PMID:[Beta adrenergic receptor blockade : a self-limited phenomenon explaining the benignancy of acute poisoning with beta adrenergic inhibitors. Report of a series of 40 patients seen at the Fernand-Widal Toxicology Center, with a 0% mortality rate (author's transl)]. 612 35

Electrophysiological tests supplemented by pharmacological stress of atrioventricular conduction with ajamaline failed to predict the development of atrioventricular block in a patient with bifascicular block and no organic heart disease.
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PMID:Failure to predict development of atrioventricular block with electrophysiological testing supplemented by ajmaline. 616 47

In a prospective randomized study we searched for arrhythmogenic effects of the tetracyclic antidepressant, a maprotiline, and the tetrahydroisoquinoline derivative, nomifensine. Forty depressive patients from the psychiatric outpatients department were included in the study. Twenty patients in each group received maprotiline or nomifensine over three weeks in the recommended daily dosage of 75 mg. Rhythm analysis was performed before therapy, at the end of 3 weeks therapy, and 1 week after withdrawal from medication using a dual channel long-term ECG with monitoring periods of 10 h during normal daily activities. Before treatment, spontaneous incidence of all ventricular ectopics and of their complex forms was within the normal range when compared with ectopic activity of 121 "normal subjects" without detectable heart disease. No significant increase could be demonstrated during therapy with maprotiline or nomifensine, nor was any change observed 1 week after medication had been stopped. The same was true for supraventricular extrasystoles; atrial tachycardia, atrial flutter, and fibrillation were never seen. Sinoatrial (n=2) and atrioventricular block (n=1) were rare findings independent of and not affected by treatment. No bundle branch blocks were observed before, during, and after treatment. In contrast, despite the conservative dosage of both drugs, a therapy-dependent increase in average heart rate was found (p less than 0.001). This increase was significantly higher in patients receiving nomifensine than in those treated with maprotiline (p less than 0.001), suggesting a lower intrinsic anticholinergic activity of the latter compound.
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PMID:Incidence of cardiac arrhythmias during antidepressant therapy with maprotiline or nomifensine. 617 91

The preimplantation arrhythmias, coexistent medical conditions, the causes of death, and survival course are described for 399 patients who received their initial ventricular pacemaker implantation for a bradyarrhythmia (AV block, sinus node disease, and hypersensitive carotid sinus syndrome) at the University of Michigan from 1961 to 1979. Factors which correlated with a poor survival are elucidated. Survival for those with sinus node disease was virtually identical to those with AV block, with only 63% surviving over five years. Advanced age and congestive heart failure prior to implantation, and underlying ischemic or hypertensive heart disease portended a poorer survival in both groups. Patients with hypersensitive carotid sinus syndrome had a distinctly better prognosis--no deaths occurred until the eight year after pacing. Patients with no underlying heart disease and those with valvular disease did remarkably better than those with an ischemic or myopathic etiology. Apparent progression or complications of the underlying heart disease was the major cause of mortality. Sudden death, congestive heart failure, myocardial infarction, and major arrhythmias were the causes of death in 48% of those who died. Implications of improved pacing modalities on late complications and death are discussed.
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PMID:Symptomatic bradyarrhythmias in the adult: natural history following ventricular pacemaker implantation. 617 56

A total of 2350 consecutive Holter recordings revealed that 53 patients had ventricular asystole of 3 seconds or more. The diagnoses based on the longest pauses were: sinus arrest in 19; AV block in 5; slow atrial fibrillation in 29. Symptoms occurred in 45 and were absent in 8 patients. Associated heart disease was present in only 33 cases. A pacemaker was implanted in 7 out of 8 asymptomatic patients. Ventricular asystole of 3 seconds or more is proposed as a definite indication for the implantation of a permanent pacemaker.
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PMID:Dynamic electrocardiography and ventricular pauses of 3 seconds and more: etiology and therapeutic implications. 619 Dec 91

Three patients are described who had situs ambiguus and left isomerism (polysplenia syndrome) and advanced atrioventricular block. One presented with a complex bradyarrhythmia with Wenckebach block. The other two had congenital atrioventricular block with a narrow QRS at a ventricular rate of 80 per minute, an atrial rate of 150' per minute, and both had a P wave axis directed superiorly and to the right in one, and superiorly to the left in the other. This ECG pattern was not observed in more than 400 adult patients with complete A-V block treated in our service. It is our opinion that in infants and children with heart disease the presence of complete A-V block with narrow QRS and an unusual P waves axis directed superiorly is strongly suggestive of left isomerism. The incidence rate of complete A-V block in left isomerism is nearly twenty percent of the cases described.
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PMID:Atrioventricular block in situs ambiguus and left isomerism (polysplenia syndrome). 619 63


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