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 10,214 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Guidelines for a step-wise plan of treatment of tachycardias have been compiled based on clinical empirical experience and with the aid of surface electrocardiograms, intracardial electrograms and stimulation techniques. The plan is primarily with the aid of surface electrocardiograms, intracardial electrograms and stimulation techniques. The plan is primarily oriented with respect to the antiarrhythmic efficacy, the adverse reactions and the practicability of the respective agents. Any type of tachycardia, including premature atrial or ventricular contractions, may be regarded as indication for treatment. Treatment is not indicated only in those asymptomatic patients with rare and evanescent tachycardias and in those with less than 300 premature contractions per hour. Beta-adrenergic blockers are the drugs of choice for the persistent sinus tachycardia. Should the latter agents be contraindicated, propafenon, amiodarone or aprindine may be administered. Verapamil and/or digitalis are indicated only for suppression of paroxysmal sinus tachycardias. Atrial premature contractions are best managed with guinidine or disopyramid. An acute reduction of rapid ventricular rates associated with atrial tachycardias, atrial flutter or fibrillation can best be attained through the administration of verapamil prior to digitalis or beta-adrenergic blockers. Re-establishment of sinus rhythm and prophylactic suppression of the latter should be undertaken with quinidine or disopyramid in combination with digitalis and/or either a beta-adrenergic blocker or intravenously-administered verapamil. Verapamil is the drug of choice for initial management of AV-junctional tachycardia for which a combination with digitalis may be considered. An alternative combination is that of a beta-adrenergic blocker and digitalis. For the acute treatment of ventricular tachycardias, lidocain has proved most effective. Although ajmaline and/or propafenon may be given should no response be obtained, electrical cardioversion would be more appropriate. To prevent ventricular tachycardia or when treatment is indicated for ventricular premature beats, ajmaline, propafenon, quinidine, disopyramid or mexiletine, occasionally in combination with a beta-adrenergic blocker should be employed. Verapamil and/or ajmaline, are usually very effective for termination of reciprocal tachycardias. Ajmaline or propafenon in combination with a beta-adrenergic blocker is recommended for the prophylactic treatment of reciprocal tachycardia. In patients who additionally have bradycardia, prolonged QT-intervals or pre-excitation syndromes, the guidelines should be modified accordingly.
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PMID:[Medical management of tachycardias (author's transl)]. 9 75

Twenty-four-hour ambulatory electrocardiographic monitoring was used to determine the incidence of arrhythmia while on-call and its relationship to stress and fatigue in 20 healthy medical interns. Mitral valve prolapse was present in 8 of 19 interns (42%). Heart rates ranged from a maximum of 103-167 beats/min (135 +/- 16) to a minimum of 38-61 beats/min (47 +/- 5). Interns had at least one episode of sinus tachycardia/h during 57% +/- 21% (range, 8-88%) of their hours on-call. Atrial premature beats (APB) were present in 19 of 20 (95%) and ventricular premature beats (VPB) in 12 of 20 (60%) subjects. APB/h ranged from 0 to 1.2 (0.4 +/- 0.3) and VPB/h from 0 to 23 (2 +/- 6). Three interns had multiform VPB and two had ventricular couplets. More APB/h occurred in interns under greater stress (0.5 +/- 0.4/h vs 0.3 +/- 0.1/h, p < 0.05) and combined stress and fatigue (0.6 +/- 0.4/h vs 0.2 +/- 0.2/h, p < 0.01). More VPB/h (5 +/- 9/h vs 0.5 +/- 0.6/h, p < 0.05) and higher (Lown) grade ventricular ectopy (2.3 +/- 1.6 vs 0.8 +/- 1.1; p < 0.05) occurred in interns under greater combined stress and fatigue. Mitral valve prolapse, sleep deprivation and caffeine intake were not associated with increased arrhythmia. The authors conclude that (1) rapid sinus tachycardia is frequent in interns while on-call and (2) interns experiencing greater stress and fatigue have more APB/h, VPB/h, and higher grade ventricular ectopy. These data support the notion that stress and fatigue may contribute to arrhythmia in healthy normal subjects.
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PMID:The effect of stress and fatigue on cardiac rhythm in medical interns. 140 19

To examine the effects of theophylline toxicity on cardiac rhythm, patients underwent continuous ambulatory ECG recording during acute theophylline toxicity and recovery. The patients, who were recruited form inpatient wards, intensive care units, and emergency departments of a University Medical Center and a Veterans Administration Medical Center, had serum theophylline concentrations (STC) greater than 30 mg/L. There were 14 men and two women with a mean age of 66 years. Fourteen patients had COPD and developed toxicity following long-term theophylline overmedication. Two patients had asthma and ingested an intentional overdose. The STC at the onset of ECG recording ranged from 23 to 67 mg/L. The principal rhythm was sinus in 15 patients; one patient had atrial fibrillation. Sinus tachycardia (heart rate greater than 100/min) was common, and heart rate fell in proportion to STC as toxicity resolved. Supraventricular ectopic beats (SVEs) were noted in seven patients with multiple runs of SVE being present in four. One patient developed multifocal atrial tachycardia (MAT) during toxicity that resolved spontaneously. During the 11 +/- 8 hours of recording during toxicity (STC greater than 20 mg/L), 80 percent of patients had ventricular premature beats (VPBs), 44 percent had paired VPBs, and 25 percent had ventricular runs. One elderly patient with heart disease developed sustained ventricular tachycardia (VT) when STC = 66 mg/L. No other patient had ventricular ectopy that required intervention. During the 10 +/- 6 hours of recording during the "recovery phase" (STC less than 20 mg/L), all patients with VPBs continued to have ectopy; however, the number of VPBs declined significantly. A follow-up 24-hour ECG recording obtained one week after recovery from toxicity in the patient with sustained VT demonstrated marked reduction in the frequency and complexity of VPBs. Patients with frequent (greater than 10/h) or repetitive VPBs were older (p less than 0.05) than those without complex ectopy. There was a trend (p = 0.07) suggesting patients with underlying heart disease were at risk for having complex ventricular ectopy. We conclude that sinus tachycardia, SVE, and VPBs are common among patients with theophylline toxicity; however, sustained ventricular or supraventricular tachyarrhythmias that require antiarrhythmic therapy are uncommon.
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PMID:Cardiac arrhythmias during theophylline toxicity. A prospective continuous electrocardiographic study. 188 98

In patients with mitral valve prolapse syndrome various disturbances of cardiac rhythm can be observed such as atrial arrhythmias, ventricular tachycardias and conduction disturbances. Of timely interest are the questions of which etiology is at the basis of the arrhythmias, what is their relevance with respect to sudden cardiac death, what are the indications for treatment and which therapeutic results can be anticipated. Cardiac arrhythmias represent the most frequent complication of mitral valve prolapse. Holter ECG monitoring has assumed the central role in detection of all types of arrhythmias. As compared with normal persons, in patients with mitral valve prolapse, both ventricular and supraventricular arrhythmias can be found more frequently. Atrial arrhythmias: Supraventricular arrhythmias can be found less frequently than ventricular arrhythmias (Table 1). Premature atrial contractions can be observed in 35% of those with mitral valve prolapse but also in a similar number of normal individuals such that their presence is not of clinical relevance. There is only a tendency to more frequently incurred supraventricular couplets in mitral valve prolapse. Supraventricular tachycardias can be observed in 10.5 to 32% of which sinus tachycardia (heart rate greater than 120 beats per minute), paroxysmal atrial tachycardia and intermittent atrial fibrillation at about 5 to 6% each are not more common than in control subjects. Atrial fibrillation was seen more frequently in mitral valve prolapse with mitral regurgitation or, conversely, in mitral regurgitation due to mitral valve prolapse more frequently than in mitral regurgitation due to other causes.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Mitral valve prolapse syndrome and arrhythmias]. 305 84

Holter monitoring was done prospectively in 50 adult patients of chronic renal failure (CRF) before and during haemodialysis. Frequent premature ventricular contractions (PVC's) were present in 3 (6%), all during dialysis (Gp I). Sporadic PVC's were seen in 6 (12%) and rest 41 (82%) had no PVC (Gp II). Premature atrial contractions (PAC's) were frequent in 5 (10%) (one had precipitation during dialysis), sporadic in 7 (14%) and none in 38 (76%). Ventricular tachycardia (VT) was not seen. Supraventricular tachycardia (SVT) was observed in 5. No biochemical parameter correlated with arrhythmias. There was no correlation between hypotension episodes and arrhythmias. Sinus tachycardia occurred during the third and fourth hours of dialysis. This correlated with hypotensive episodes observed in 13 patients. Episodes of silent myocardial ischaemia (SMI) observed in 12 patients occurred predominantly during this period of tachycardia. Cardiac arrhythmias are infrequent in CRF and are mainly seen in patients with preexisting coronary artery disease with low ejection fractions (EF) (EF 0.37 +/- 0.2 in Gp I and 0.80 +/- 0.1 in Gp II P < 0.01) and abnormal Q waves in baseline ECG. They do not seem to contribute to occurrence of episodes of dialysis induced hypotension.
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PMID:Holter monitoring in chronic renal failure before & during dialysis. 788 83