Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to determine whether an antiarrhythmic, Ajmaline, could have proarrhythmic effects on the atrium and to compare the results with those of other antiarrhythmic drugs. A total of 1950 patients without cardiac failure or recent (less than 6 weeks) myocardial infarction were given 1 mg/kg of Ajmaline intravenously during electrophysiological investigation. A proarrhythmic effect was defined as the occurrence of supraventricular tachycardia (SVT) in a patient without this arrhythmia before the test or the facilitation of its induction. Fifty five patients developed SVT (mainly atrial tachyarrhythmias: 48 cases, and some junctional tachycardia: 7 cases) which occurred spontaneously in 22 patients and during fixed atrial pacing in 33 patients. Fifteen patients developed ventricular tachycardia (VT). The predisposing factors for the development of SVT were: a previous history suggesting spontaneous SVT (28 patients; 51 p. 100); sinoatrial block (14 patients--the only abnormality in 10 cases). Seventeen patients had none of these factors but 8 had known cardiac pathology and the other 9 were relatively elderly patients (79 years). Twelve of the patients developing VT had known cardiac disease, bundle branch block in 12 cases and previous VT in 6 cases. In conclusion, proarrhythmic effects of Ajmaline are infrequent if its contraindications are respected, but they do exist at both atrial (2.8 p. 100) and ventricular levels (0.8 p. 100): the risk factors are comparable: previous spontaneous arrhythmias or ECG changes (SA block at the atrial and bundle branch block at the ventricular level).
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PMID:[Arrhythmogenic effect of ajmaline on the atrial level]. 251 24

The authors report their experience of permanent exclusive atrial pacing in the treatment of sinus node dysfunction in a series of 65 cases with a follow up of 1 to 5 years (average 37.6 months; 2406 patients months), 41 women and 24 men aged 74 +/- 3 years. Sixty one patients were symptomatic. The diagnosis was made from surface ECG recordings in 54 cases (83 p. 100) and after electrophysiological investigation in 11 cases (16 p. 100). Atrioventricular conduction was carefully evaluated before implantation: PR equal to or less than 200 ms, Wenckebach point equal to or greater than 130/min, absence of ventricular pauses longer than 3,000 ms after carotid sinus massage, HV interval equal to or less than 55 ms [measured in 57 cases (87 p. 100)], negative Ajmaline test in 6 patients with intraventricular conduction defects. Performed J-shaped atrial leads with active (66 p. 100) or passive fixations (34 p. 100) were implanted by an endocavitary approach (right subclavian vein in 60 cases: 92 p. 100). There were 3 cases of early lead displacement and one patient developed an elevated threshold of pacing. There were 5 deaths during the follow-up period (3 of cardiovascular origin). The neurological symptoms disappeared in 93 p. 100 of cases. No cases of cardiac failure were observed after permanent pacing. Fifteen patients had documented supraventricular arrhythmias before implantation; 5 patients continued to have the same paroxysmal or permanent arrhythmias but 10 patients had no further recurrences, 8 with and 2 without antiarrhythmic therapy.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Exclusive permanent atrial stimulation. Clinical experience apropos of 65 cases with a follow-up of 1 to 5 years]. 310 82

Nine cases of major ventricular arrhythmia (tachycardia (VT), fibrillation (VF), torsades de pointe) are reported in patients with sequellae of myocardial infarction but without residual angina or cardiac failure. --Six of these disturbances of excitability occurred after a bradycardia due to sino atrial block (SAB) which favoured the breakthrough of abnormal automatic foci. This form of the bradycardia-tachycardia syndrome was demonstrated by endocavitary electrophysiological exploration.. These were the only cases of major ventricular arrhythmia observed in a series of 88 SABs. Reputedly benign, they illustrate the potential gravity of a conduction defect in patients with sequellae of myocardial infarction. --Three other cases of abnormal ventricular excitability complicating the administration of 1 mg/kg of Ajmaline to test for paroxysmal block after myocardial infarction. These were the only cases of VT observed in a series of 800 Ajmaline tests. The three patients have had no further episodes of VT after 1 year's follow-up. On the other hand, in 43 Ajmaline tests without VT in patients with myocardial infarction, 6 cases of VT and 1 lethal VF were later observed. This demonstrates the lack of significance of episodes of VT during Ajmaline tests, the depressant action of the drug on intracardiac conduction favouring the initiation of reentry. In conclusion, a history of myocardial infarction exposes the patient to the risk of major ventricular arrhythmias in SAB, the detection of which should indicate pacemaker therapy from the first symptoms. The use of an intravenous antiarrhythmic agent should be avoided as it may aggravate arrhythmias. However, the arrhythmia is of no prognostic significance.
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PMID:[Danger of sinoatrial block and the use of antiarrhythmic agents in myocardial infarcts]. 681 68