ABSTRACT
The antiarrhythmic effect of metoprolol after chronic treatment has been evaluated by 24 hour Holter monitoring in 16 patients with several premature ventricular beats and in 14 patients with chronic atrial fibrillation and compared with the effect of a placebo. Metoprolol induced a mean decrease of heart rate of 14.5% in the 16 patients and reduced the mean value/min of the ventricular premature beats of the 51.2%. In addition the use of metoprolol abolished the ventricular premature beats in 9 cases, while in two cases there was an increase of their frequency. In the 14 patients with chronic atrial fibrillation metoprolol was able to reverse to sinus rhythm three of the patients and in the remaining 11 decreased the ventricular heart rate of the 33%.
Subject(s)
Arrhythmias, Cardiac/drug therapy , Metoprolol/therapeutic use , Propanolamines/therapeutic use , Clinical Trials as Topic , Humans , Middle Aged , PlacebosSubject(s)
Coronary Disease/diagnosis , Electrocardiography , Exercise Test , Humans , Male , Middle Aged , RestABSTRACT
Five different stress testing methods: bicycle ergometer exercise (BE), treadmill exercise (TD), isoproterenol infusion test (IPN), dopamine infusion test (DPM), and atrial pacing (AP), were performed on 90 male patients who underwent coronary arteriography. Ischemic S-T segment depression of 1.0 mm or greater was used as the criterion for a positive test. Within the group of 56 subjects having significant coronary artery disease (CAD) the diagnostic sensitivity of the single tests was as follows: 64.3% for BE, 66.1% for TD, 69.6% for IPN, 41.1% for DPM, 75.0% for AP. For the 34 subjects with no CAD the folowing specificity was found: 88.2% for BE and for TD, 82.3% for IPN, 85.3% for DPM, 63.8% for AP. When the results of the different tests were combined, it was seen that the association of an ergometric test with IPN enhanced the sensitivity of the exercise test (p less than 0.05) without significantly decreasing the specificity.
Subject(s)
Coronary Angiography , Coronary Disease/diagnosis , Exercise Test/methods , Adult , Aged , Cardiac Pacing, Artificial , Cineradiography , Coronary Disease/diagnostic imaging , Dopamine , Electrocardiography , Humans , Isoproterenol , Male , Middle AgedSubject(s)
Coronary Disease/diagnostic imaging , Diatrizoate Meglumine , Diatrizoate/analogs & derivatives , Iothalamic Acid/analogs & derivatives , Adult , Coronary Angiography , Diatrizoate Meglumine/pharmacology , Electrocardiography , Electrolytes/metabolism , Heart/drug effects , Heart Ventricles/diagnostic imaging , Hemodynamics/drug effects , Humans , Iopamidol , Iothalamic Acid/pharmacology , Male , Middle Aged , Myocardial Contraction/drug effects , Myocardium/metabolismABSTRACT
A forty-five year old man with longstanding rheumatic heart disease whose surface electrocardiogram (ECG) showed absent P waves and two alternating QRS complex rhythms, one regular and the other irregular, was submitted to electrophysiological studies. For regular QRS complex rhythm these studies revealed (1) presence of total and bilateral atrial standstill and (2) regular ventricular rhythm originating in the A-V junction; while for irregular QRS complex rhythm the studies showed (1) presence of atrial standstill in the area of the upper right atrium, and (2) a +/- 150/min atrial activity rate in the intracavitary and esophageal electrogram and a +/- 300/min rate in the epicardial mapping. The spread of conduction of this atrial activity indicates that it originated within an atrial area near the tricuspid valve. The presence of an alternating partial and total atrial standstill is a unique feature which to data has not been reported in the literature.
Subject(s)
Arrhythmias, Cardiac/diagnosis , Electrocardiography , Heart Atria , Action Potentials , Adolescent , Adult , Arrhythmias, Cardiac/complications , Arrhythmias, Cardiac/physiopathology , Atrial Fibrillation/complications , Bundle of His/physiopathology , Heart Failure/complications , Heart Valve Prosthesis , Humans , Male , Middle Aged , Mitral Valve Stenosis/complications , Mitral Valve Stenosis/surgery , Rheumatic Heart Disease/complications , Tricuspid Valve Insufficiency/complications , Tricuspid Valve Insufficiency/surgeryABSTRACT
Two cases of carotid sinus syndrome with peculiar clinical and nosological characteristics are presented. The clinical symptoms were characterized by syncope with bradicardia and hypotension, which occurred contemporarily or independently of each other. The most valuable medical therapy to prevent or got over the syncopal attacks has proved to be one associating the sympathicomimetic drugs (high dosage dopamine, particularly on demande pacemaker. Complete decrease of symptoms following was obtained only after surgical treatment: denervation of carotid sinus in one case, intracranical section of the glosspharyngeal nerve and of the two vagal termination nearer to IX in the other case. This last result makes it possible to consider the case in question from an original nosological point of view exploiting the pathogenetic importance of stimulating the afferent nerve-fibres of the glossofaryngeal-nerve.
