benzofurans and Heart-Valve-Diseases

In order to evaluate the effects of amiodarone on thyroid function in chronically treated patients, 43 consecutive patients, who had been taking a mean weekly dose of 1420 +/- 488 mg for more than 9 months (mean 16.5 months), were studied. In a first evaluation, three patients with hypothyroidism and two with hyperthyroidism were discovered. In the remaining 38 patients, mean T4 (131 +/- 38 nmol/L) and rT3 (0.85 +/- 0.3 nmol/L) levels were significantly higher than reference values (p less than 0.05 and p less than 0.001, respectively), and mean T3 levels (1.89 +/- 0.73 nmol/L) were significantly lower (p less than 0.001). Thirteen patients showed hyperresponsiveness to thyrotropin-releasing hormone (TRH) stimulation testing. In a second evaluation, performed 12 to 18 months later, two new cases of hypothyroidism were discovered. T3 levels showed significantly lower values (p less than 0.02) than in the first evaluation, whereas basal thyroid-stimulating hormone levels and levels 30 and 60 minutes after TRH stimulation were significantly higher than those in the first evaluation (p less than 0.001). Five new hyperresponders to TRH were found. In the present series, the progressive appearance of clinical thyroid dysfunction with an elevated total incidence (16%) is demonstrated. Moreover, a progressively high prevalence of hyperresponsiveness to TRH stimulation is shown. These findings indicate that chronic amiodarone administration may carry a high risk of thyroid dysfunction.

Topics: Adult; Aged; Amiodarone; Benzofurans; Chronic Disease; Coronary Disease; Female; Follow-Up Studies; Goiter; Heart Failure; Heart Valve Diseases; Humans; Hyperthyroidism; Hypothyroidism; Male; Middle Aged; Thyroid Function Tests; Thyroid Gland

Our use of amiodarone in 200 patients during an 8-year period confirms our previous experience which indicated that the drug was close to being the ideal antiarrhythmic agent in children's arrhythmias. Its absence of cardiac toxicity, its powerful antiarrhythmic properties, its depressive effect on the AV nodal conduction, combined with its beta-inhibitory effect makes it effective and harmless in practically all forms of atrial, junctional and ventricular arrhythmias, whatever the reentrant or automatic mechanism of the arrhythmia. The metabolism is much faster in children than in adults, making the drug active in a few hours, with a lesser prolonged duration of action. Though there is practically no limitation for its use on a short- or mean-term basis, the long-term use must be limited to truly refractory arrhythmias, a situation which is rarely encountered. In such cases, combining amiodarone with conventional therapy allows a decrease in the maintenance dosage and a lower incidence of extracardiac side effects.

Topics: Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Atrial Flutter; Benzofurans; Bundle-Branch Block; Child; Electrocardiography; Heart Conduction System; Heart Defects, Congenital; Heart Valve Diseases; Heart Ventricles; Humans; Infant; Tachycardia

Topics: Adult; Amiodarone; Arrhythmias, Cardiac; Atrial Fibrillation; Benzofurans; Cardiomyopathies; Female; Heart Valve Diseases; Humans; Male; Middle Aged; Mitral Valve; Quinidine

Topics: Adolescent; Adult; Aged; Benzoates; Benzofurans; Blood Glucose; Carbohydrate Metabolism; Coronary Disease; Coumarins; Dipyridamole; Female; Glucose; Glycolates; Heart Valve Diseases; Humans; Isosorbide Dinitrate; Lactates; Male; Middle Aged; Myocardium; Propylamines; Pyruvates; Stimulation, Chemical; Vasodilator Agents; Verapamil; Xanthines