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Query: UMLS:C0033036 (APC)
 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

The etiology and clinical significance of sustained arrhythmias, and atrial and ventricular premature complexes (APCs and VPCs, respectively) after heart transplantation are controversial. Fifty adult recipients surviving > 2 weeks were studied by continuous telemetry while in the hospital and by ambulatory electrocardiographic monitoring at 2, 4, 6, 12 and 24 weeks after transplantation. The median APC frequency was greater among subjects who experienced allograft rejection in the early postoperative period (0.7/hour, range 0 to 23) than among those who did not (0.2/hour, range 0 to 10.4) (p = 0.04). The APC frequency in all subjects decreased from 0.25/hour (range 0 to 23) early to 0/hour (0 to 14) later (p = 0.04). Atrial flutter was the most frequent sustained arrhythmia; it was recorded in 5 of 21 rejectors and in 1 of 29 nonrejectors (p = 0.04), and 11 of 16 episodes (69%) were related to acute rejection temporally. VPCs were recorded in all patients early after transplantation, but the median frequency subsequently decreased from 4.6/hour (range 0.5 to 470) early to 1.25/hour (range 0 to 225) later (p < 0.001). VPC frequency was unrelated to rejection. Sustained ventricular tachycardia was recorded once and was caused by the proarrhythmic effect of flecainide. Thus, APCs and VPCs occur frequently after transplantation. Frequent APCs are associated with rejection, whereas the main determinant of VPC frequency is time after transplantation. Atrial flutter is closely associated with rejection and should be regarded as an indication for endomyocardial biopsy. Ventricular tachycardia occurs seldom, and in this study was due to proarrhythmic drug effects.
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PMID:Arrhythmias after cardiac transplantation. 138 2

Atrial premature beats seldom require an antiarrhythmic treatment; reassurance and suppression of coffee, alcohol, and tobacco generally suffice. Acute atrial fibrillation is best treated by electrical cardioversion if it induces acute cardiovascular decompensation. If it is not poorly tolerated, the arrhythmia may be treated with digitalis at doses sufficient to keep the ventricular response rate at 70-90/min. This therapy may restore sinus rhythm, but conversion to sinus rhythm often requires the combined use of digitalis with a beta-blocker or class I antiarrhythmic drug (quinidine, disopyramide, procainamide, propafenone, or flecainide). Digitalis must be avoided in the presence of a preexcitation, and class IA agents, which facilitate atrioventricular (AV) nodal transport, must never be used without digitalis. Chemical cardioversion may also be achieved by i.v. amiodarone. Long-term prevention of recurrences after cardioversion or in the presence of recurrent paroxysmal atrial fibrillation requires digitalis combined with a class I agent, or a beta-blocker, preferably sotalol. Amiodarone is also very efficacious. Special mention should be made of atrial fibrillations of vagal or sympathetic origin, which are best treated by amiodarone, or beta-blockade (nadolol), respectively. In the presence of chronic established atrial fibrillation, digitalis in combination with a beta-blocking agent or a calcium antagonist, such as verapamil or diltiazem, may be useful to slow the ventricular response rate. If successful control cannot be obtained, catheter ablation of the AV node with implantation of a rate-responsive pacemaker must be contemplated. The therapeutic approach in patients with chronic atrial fibrillation, whether or not associated, is similar to atrial flutter.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Antiarrhythmic treatment of atrial arrhythmias. 172 15

The authors examined the prevalence and significance of cardiac rhythm disturbances in healthy elderly individuals. They selected 26 men with active lifestyles, aged 70-81 years, after clinical, routine blood tests, chest radiographs, echocardiography, resting and exercise electrocardiography, and Gated cardiac blood imaging evaluations. The men were submitted to continuous electrocardiographic monitoring during their daily routine. The recording time ranged from 838 to 1,432 min (average = 1,307 +/- 153 min). Clinical follow-up was done every six months. Sinus rhythm predominated in all subjects. The maximal, minimal, and average heart rate ranges (beats/min) were, respectively: during sleeping periods, 60-115 (85.8 +/- 13.2), 42-80 (56.6 +/- 8.7), 51-85 (64.0 +/- 8.8); and during awake periods, 85-150 (118.4 +/- 16.4), 50-85 (64.1 +/- 9.1), 61-90 (75.3 +/- 8.3). The longest sinus pauses were observed during sleep and ranged from 0.8 to 2.5 sec (1.25 +/- 0.34 sec). Atrial ectopic beats were observed in 20 individuals (76.9%). They were frequent in four (15.4%) and repetitive in nine (34.6%) of them. Short-lasting episodes of paroxysmal atrial tachycardia and paroxysmal atrial flutter were observed in one case each. Ventricular ectopic beats were recorded in 20 individuals (76.9%). They were frequent in 6 (23%) and multiform in 13 (50%) of them. Couplets were observed in 5 cases (19.2%) and episodes of nonsustained ventricular tachycardia were present in 3 individuals (11.5%). No symptoms were referred by any individual during recording. No clinical signs of heart disease or symptoms were noticed during the average 40 +/- 7.2 months of follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Frequency and significance of cardiac rhythm disturbances in healthy elderly individuals. 234 17

To determine the type and frequency of supraventricular arrhythmias in patients with mitral stenosis and sinus rhythm we studied 63 such patients, mean (sd) age 48.8 (8.2) years, by 24 hour ambulatory ECG monitoring. Thirty-five patients (55.6%) had supraventricular tachyarrhythmias. Twenty-five (39.7%) had paroxysmal atrial tachycardia, 14 (22.2%) atrial fibrillation, 8 (12.7%) multifocal atrial tachycardia and 5 atrial flutter. Ninety-five per cent (101) of episodes were asymptomatic and 96% non-sustained. Supraventricular premature beats occurred in 59 patients with couplets and triplets in 40 (63.5%) and 28 (44.4%), respectively. Frequent supraventricular premature beats, couplets, triplets and episodes of paroxysmal arrhythmias were commoner in patients greater than 50 years. Ectopic atrial rhythms with varying P wave morphology occurred in 12 patients (19%). Nine patients (14.3%) had suffered systemic embolic episodes. We conclude that supraventricular ectopic and tachyarrhythmias occur frequently in patients with mitral stenosis and sinus rhythm and that most paroxysms are non-sustained and asymptomatic.
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PMID:Holter monitoring in patients with mitral stenosis and sinus rhythm. 243 16

The clinical characteristics of supraventricular tachyarrhythmias (SVTA) and their relation to left ventricular dysfunction were assessed in 208 consecutive patients with recent myocardial infarction. Arrhythmias were quantified on hospital discharge by 24 hour electrocardiographic recording. All the variables were evaluated between the second and the fourth week after infarction. SVTA occurred in 113 (54%) patients: Supraventricular premature beats (SVPB) in 49 (24%), frequent or repetitive SVPB in 37 (18%), atrial or junctional tachycardia in 23 (11%), atrial flutter or fibrillation in 4 (2%). Most of these arrhythmias occurred in the absence of symptoms, and the most complex forms were always selflimiting. No relation was found among the presence of different forms of SVTA and sex, coronary risk factors, previous history of ischemic heart disease, type or site of acute myocardial infarction, NYHA functional class. Age, left atrial dimension (LAD), cardio-thoracic ratio (CTR) and left ventricular ejection fraction (LVEF) at rest differed significantly among three groups of patients: those without SVTA, those with SVPB less than 100 per hour and those with frequent-repetitive SVPB or atrial-junctional tachycardia. The more SVTA complexity, the worse LAD, CTR, LVEF and the higher the age. Multivariate discriminant analysis showed that CTR was directly and LVEF inversely related to the occurrence of SVPB less than 100 per hour, while the presence of frequent-repetitive SVPB or supraventricular tachycardia was closely related to increasing age, LAD, CTR and decreasing LVEF. Patients with atrial fibrillation always showed the worst values of LAD, CTR, LVEF and age. The results of the present study show that different types of SVTA occurring at discharge from hospital after myocardial infarction are clinically benign, but always suggestive of different degrees of left ventricular dysfunction.
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PMID:The relation between supraventricular tachyarrhythmias and left ventricular dysfunction after acute myocardial infarction. 326 15

Sixty-six patients in whom atrial pacemaker (AAI) were implanted were followed for one year to 5 years for the occurrence of pacing failure, sensing problems, and later AV block. Pacing failure occurred in only one patient and sensing problems occurred in 15 patients but 10 of them improved after a change of sensing. Temporal change of AV conductivity was not recognized in the majority of patients. Eighteen patients developed transient decrease in AV conductivity. Two patients developed persistent decrease in AV conductivity and ended in clinical AV block for which the pacemaker was implanted. Out of 66 patients, 22 had a history of paroxysmal atrial flutter or fibrillation (AFF) prior to AAI implantation. They were divided into two groups. Group I consisted of 20 patients in whom paroxysmal AFF disappeared after AAI implantation. Group II consisted of 22 patients in whom paroxysmal AFF persisted after AAI implantation. Electrophysiological studies prior to the AAI implantation showed that sinus rate at control was significantly slower (36.3 +/- 10.1 beats per min in Group I, 57.1 +/- 10.8 beats per min in Group II), atrial fragmented activity zone was significantly narrower (62.7 +/- 32.9 msec in Group I, 88.1 +/- 19.7 msec in Group II), and the occurrence of PAC was less at an atrial pacing rate of 70 beats per min (8% in Group I, 67% in Group II) in Group I compared to Group II.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Problems and anti-tachyarrhythmic effects of chronic atrial pacing. 398 96

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

A survey was made on a population of 6059 subjects aged more than 60 years with the aim to assess 1. the prevalence of heart arrhythmias and 2. the relationships between arrhythmias and some other ecg alterations. Arrhythmias resulted present in 29.0% of the whole population with a significantly higher prevalence among males (30.7% vs 28.1%, P less than 0.05) and among subjects over 75 years of age (33.2% vs 23.9%, P less than 0.001). Supraventricular extrasystoles (SE, 11.55%), atrial fibrillation (AF, 10.44%) and ventricular extrasystoles (VE, 8.91%) were the most frequent arrhythmias, followed by sinus bradycardia (SB, 2.04%), sinus arrhythmia (SA, 1.35%), atrial flutter (AFL, 1.09%) and junctional rhythms (JR, 0.20%). AF and AFL resulted significantly more frequent among females, whilst SE, VE and SB were more frequent among males. All the above arrhythmias, with the exception of AFL and JR resulted significantly more frequent among subjects over 75. A significantly higher prevalence of ecg signs of left ventricular hypertrophy, ischemia, previous myocardial infarction (MI) and of the so-called "minor" T-wave changes (MTC) was found among the subjects with arrhythmia as compared with those free from rhythm disturbances. Ecg signs of MI and MTC were significantly more frequent among males and MTC were more frequent among females and among subjects over 75. It is concluded that in an old person the presence of an arrhythmia should lead to a careful evaluation of the general and cardiological clinical situation in order to avoid 1. to prescribe an unnecessary and potentially dangerous antiarrhythmic treatment, and 2. to misdiagnose an underlying clinical condition liable to a decisive improvement under adequate treatment.
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PMID:[Arrhythmias in the elderly]. 619 Jan 9

A 58 year old man who died of metastatic carcinoma had undergone electrophysiological investigation 4 years previously for a Wolff-Parkinson-White syndrome (Rosenbaum Type A, Frank and Boineau Type IV) associated with supraventricular tachycardia (SVT) at 180/mn, atrial fibrillation and flutter and slow junctional (or low atrial) rhythm at 70-80/mn. Atrial extrasystoles or appropriate atrial stimulation not only induced and terminated the SVT but also the junctional rhythm and allowed passage from one arrhythmia to another. These studies showed the presence of a left lateral Kent bundle responsible for orthodromic SVT with retrograde conduction through the accessory pathway, and suggested that the junctional rhythm might be due to longitudinal dissociation of the AV node. Autopsy findings confirmed the presence of the left posterolateral Kent bundle in an almost horizontal position, parallel to the mitral annulus (it might therefore have escaped eventual surgical section) and the longitudinal dissociation of the AV node.
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PMID:[Wolff-Parkinson-White syndrome and longitudinal dissociation of the atrioventricular node. Anatomical and electrophysiological correlates]. 679 2


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