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)

In the present study: (a) physiopathology, (b) clinics, and (c) therapy of cardiothyreosis are discussed. (a) The hyperkinetic syndrome, the earliest clinical sign in thyrotoxicosis (vasodilatation, increase in inotropism, automatism, etc.), is mediated by a two-fold increase in the number of beta-receptors, and supported by an adequate synthesis of ATP and creatinphosphate (CP) in the young and, to a lesser extent, in the elderly. Genetical heart reserves are mobilized, thus significantly increasing the number and the size of mitochondria and also the enzymatic equipment (such as: the alpha-glycerophosphate-dehydrogenase, malic, pentosic cycles, etc.), a.s.o. Due to an excessive adrenergic action (glycogenolysis, an excessive oxygen consumption, up to necrosis, the ATP and CP syntheses dramatically drop; the phosphorus/oxygen ratio decreases to 2 (normal = 4). In this condition, the high functional cardiovascular performances are also impaired (the submaximal effort capacity is attained at a smaller and smaller oxygen consumption; Propranolol 2 mg i.v. decreased the cardiac output by above 30% (vs 10%--normal); electrocardiogram presents aspects of "coronary disease", tachycardia, etc.). An ultrastructural damage occurs: from "mitochondrial disease", partial lysis of myofibrils, to myofibrosis (revealed postmortem), in spite of a reduced degree of coronary atherosclerosis. Ultrastructural and biochemical experimental data support this point of view. (b) The incidence, precocity and severity of the thyrotoxic heart increase with age and the existence of a previous cardiovascular pathology. Cardiothyreosis is not present under 27 years; in 4,353 patients its incidence is of 25% (arrhythmia--21%, heart failure--12%, coronary insufficiency--1-3%). Of a major interest are tachyarrhythmias which may lead to a high mortality by hypodiastolic congestive heart failure, heart failure with secondary hyperaldosteronism, thromboembolic episodes and ventricular fibrillation. Thyrotoxicosis favours the disease of papillary muscles--mitral prolapse and insufficiency, reversible especially in children. (c) The treatment of thyrotoxic heart is an etiologic one (medical, surgical, radioactive--the last two being preferable after the adequate medical therapy). In particular, cardiothyreosis requires a reinforced irradiation (10,000 rads instead of 7,000 rads) in smaller 131I doses. The protection against the increased nocivity of catechols in thyrotoxicosis is very important (which explains the high mortality in the thyrotoxic "storm") and requires propranolol; doses above 2 mg/kilo body/day are recommended. In the elderly, the sensitivity to propranolol decreases: verapamil i.v. is more efficient in paroxysmal tachyarrhythmias (flutter, atrial fibrillation) and in those occurring intra-operatively during halothane narcosis. The anticoagulant therapy is administered in tachyarrhythmias with high ventricular rate, especially in the elderly, to avoid the embolic risk, higher in defibrillation condition.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Cardiothyreosis. 182 Oct 70

We reviewed the records of 26 infants with congenital junctional ectopic tachycardia (JET) from seven institutions to examine the evolution in the management of this tachycardia that is difficult to treat. JET was defined electrocardiographically as an incessant tachycardia with normal QRS morphology and atrioventricular (AV) dissociation. The ventricular rate ranged from 140 to 370 beats/min (mean, 230 beats/min); 16 of 26 patients had cardiac failure. Treatment success was defined as a stable decrease in the rate of JET, below 150 beats/min; partial success was a significant decrease of JET rate with alleviation of symptoms. All patients received digoxin with no significant effect. Propranolol was given to 16 patients, with two successes and one partial success. Combinations of other conventional agents were used in 11 patients with two successes; 14 patients were treated with amiodarone, which resulted in eight successes and three partial successes; three patients died suddenly on medical treatment (amiodarone, one patient; propranolol, one patient; or amiodarone plus propranolol, one patient); sudden AV block was a possible cause and consequently, two later patients had pacemaker implantation as well as medical treatment. His catheter ablation was successfully performed twice but contributed to death in a newborn; three surgical His ablations were performed for intractable JET with two successes and one death. The overall mortality was 35%. Among survivors, treatment has been stopped without any complications in five patients ranging in age from 10 months to 8 years (mean, 3.5 years). It seems that amiodarone alone is the best drug for treatment of congenital JET; necessity for permanent pacing remains unsettled. His ablation should be reserved only for intractable JET.
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PMID:Evolving concepts in the management of congenital junctional ectopic tachycardia. A multicenter study. 218 49

Dynamic cardiomyoplasty has been performed clinically to provide a substitute for myocardium, to assist dyskinetic ventricles, and to benefit patients with Chagas disease or dilated cardiomyopathy. Encouraging results have been observed for the patients; however, a conclusive experimental study is not available. How to use conditioned skeletal muscle for maximal augmentation of cardiac function in an appropriate animal model is the goal of this study. Dogs were used for heart failure induction, for single versus burst muscle stimulation, and for cardiac function augmentation. Muscle transformation was documented by histochemical evaluations. Propranolol infusion (3 mg/kg) induced temporary heart failure for 4 to 6 hours with significantly decreased cardiac output and blood pressure. Dynamic cardiomyoplasty significantly improved hemodynamic function during induced heart failure with better improvement by multiple (burst) stimulation as compared with single stimulation. Skeletal muscle fiber orientation is a critical factor for the success of this procedure. Our results indicated that skeletal muscle fiber oriented circumferential to the heart and perpendicular to the ventricular septum is the preferred procedure for dynamic cardiomyoplasty.
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PMID:The importance of skeletal muscle fiber orientation for dynamic cardiomyoplasty. 229 46

To establish the criteria for the selection of a beta-adrenergic blocking agent (beta-blockers) suitable for the long-term treatment of tremor, 20 patients with essential tremor were treated with five different types of beta-blockers. All beta-blockers were effective for essential tremor, but their efficacy differed. The weaker the intrinsic sympathomimetic activity (ISA) and the more marked the membrane stabilizing activity (MSA), the more marked was the anti-tremor effect. Propranolol, which showed the strongest anti-tremor effect, had no ISA, but its long-term administration induced symptoms of heart failure, such as pretibial oedema, in most cases. In most of these cases, when propranolol was replaced by indenolol, which showed a very slight ISA, the pretibial oedema subsided and well-controlled tremor was maintained over a long period. With regard to efficacy and usefulness, it was thought that the beta-blockers with a very slight ISA and a marked MSA, such as indenolol, was most suitable for the long-term treatment of essential tremor.
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PMID:Comparative studies on the effects of beta-adrenergic blockers in essential tremor. 289 95

Amrinone, a positive inotropic-vasodilator agent, was administered to anaesthetised dogs in an attempt to reverse heart failure induced by drugs possessing negative inotropic properties. Propranolol, a beta-adrenergic blocker; verapamil, a calcium slow-channel blocker procainamide, a type 1 antiarrhythmic agent; or sodium pentobarbital, a barbituate; administered as a bolus injection and/or infusion, produced a sustained depression in canine cardiac function. Cardiac depression was characterised by a greater than 40% reduction in cardiac contractile force (CF) and maximum left ventricular pressure development (LV dp/dtmax), a 30 to 50% reduction in cardiac output (CO) and concomitant increases in mean central venous or mean right atrial blood pressures (CVP, RAP, respectively). Amrinone, when administered intravenously as a bolus injection (1 or 3 mg X kg-1) plus an infusion (0.03 or 0.1 mg X kg-1 X min-1) reversed the depression in cardiac function by increasing CF, CO and LV dp/dtmax and decreasing preload CVP or RAP in all four drug-induced failure models. Due to the vasodilator properties of amrinone, afterload, total peripheral resistance (TPR), was reduced in verapamil and procainamide failures as well as in propranolol failure, the only model where TPR increases. In another model of heart failure, in which ouabain-induced arrhythmias preceded procainamide toxicity, amrinone was also an effective cardiotonic agent. Ouabain's inotropic effect was studied in propranolol-induced heart failure. Although an increase in LV dp/dtmax and a decrease in CVP were noted, ouabain (40 micrograms X kg-1 iv) increased TPR and had little effect on the depression in CF and CO. Drug-induced models of heart failure were useful pharmacological tools for evaluating the cardiotonic agent's ability to overcome severe cardiac depression. In propranolol-, verapamil-, procainamide-, and pentobarbital-induced cardiac toxicity, amrinone could be of therapeutic value.
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PMID:The beneficial effect of amrinone on acute drug-induced heart failure in the anaesthetised dog. 404 15

Forty-nine thyrotoxic patients prepared for partial thyroidectomy with the beta-adrenoceptor blocking drug, propranolol, and iodine are compared with 42 patients prepared with carbimazole and iodine. The age and sex distribution of the two groups were comparable, but patients with obstructive airways disease and possible cardiac insufficiency were excluded from preparation with propranolol. The mean duration of preoperative treatment with propranolol was 40 days, compared with 89 days for carbimazole. Propranolol treated patients had lower pulse rates before and after operation. The serum PB(127)I values immediately before and after operation were higher in the propranolol group than in the carbimazole group, but were the same in both groups one and four months after operation. The incidence of hypothyroidism at one year after operation was 30% in the carbimazole prepared patients and 31% in the propranolol patients. Serum calcium levels were higher in the propranolol group at the time of operation. No adverse effects from the use of propranolol and at operation the thyroid gland prepared with propranolol was firmer, less friable, more easily mobilised and less likely to bleed than the gland prepared with carbimazole. There is, consequently, less risk of damage to the parathyroid glands and recurrent laryngeal nerves. However, the basal metabolic rate remains high on propranolol therapy and very careful supervision is advised.
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PMID:Propranolol in the surgical management of thyrotoxicosis. 413 75

In a controlled double-blind study practolol, a new cardioselective beta-blocking drug, was given to 15 patients with angina pectoris, and compared with propranolol 80 mg. q.d.s. The dose of practolol ranged from 200 to 600 mg.b.d. and was decided by initial open titration in individual patients. Though practolol did not influence the incidence of angina or glyceryl trinitrate consumption, it increased the duration of exercise possible in exercise tests and reduced the amount of ischaemic S-T depression in the radiocardiogram during exercise. Propranolol reduced the incidence of angina and, in the exercise tests, increased the amount and duration of exercise but did not affect the degree of S-T depression. Unlike propranolol, practolol did not produce any adverse effects on bronchial smooth muscle. Hence it is concluded that practolol is an effective drug in treating angina, and in the dosage used is of potential value in patients with asthmatic bronchitis and angina. It should, however, be used cautiously in anginal patients with heart failure.
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PMID:Clinical evaluation of practolol, a new cardioselective beta-blocking agent in angina pectoris. 439 83

When used in the treatment of hypertension propranolol is at least of similar potency to bethanidine, guanethidine, and methyldopa. Propranolol does not produce postural or exercise hypotension and it seems that it is often more acceptable to patients than conventional drugs. It usually produces the best control of the supine blood pressure.A series of 109 hypertensive patients was treated with propranolol; in nine the drug was withdrawn. In 92 of the patients a supine or standing blood pressure of 100 mm. Hg or less was achieved. Eighty of the patients had previously been treated with other potent drugs, and close comparisons and prolonged follow-up in 17 patients showed that diastolic pressures of 100 mm. Hg or less were achieved in more patients after propranolol than with guanethidine, bethanidine, or methyldopa.Sensitivity to propranolol varies widely, and dosage should be increased gradually. The hypotensive effect often takes six to eight weeks to reach its maximum. Propranolol reduces cardiac output but may also act by reducing the cardiac component of pressor stimuli; as a result the baroreceptors gradually regulate the blood pressure at a lower level. It is contraindicated in patients with obstructive airways disease or in uncompensated heart failure.
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PMID:Treatment of hypertension with propranolol. 576 14

All available beta-adrenergic blocking agents share the property of blocking beta 1 adrenoceptors, including those in the heart. They differ, however, in their ability to block beta 2 receptors (cardioselectivity), their membrane stabilizing action, intrinsic sympathomimetic activity and their pharmacokinetic properties. The strongest evidence for efficacy in secondary prevention has been obtained with timolol, metoprolol and propranolol. Timolol and propranolol block all beta-receptor-mediated responses and are therefore nonselective, whereas metoprolol is relatively cardioselective. Propranolol and metoprolol have membrane stabilizing action, but timolol does not; none of these agents show intrinsic sympathomimetic activity. Thus, no ancillary property is a requirement for efficacy. All of these agents may precipitate heart failure, but this problem has been exaggerated, and transient failure during the early course of myocardial infarction is no longer a contraindication to therapy. Cardioselective agents cause less bronchospasm, but this can still occur, especially with higher dosages. In addition, these agents probably cause somewhat less fatigue and result in less hypertension during hypoglycemia than nonselective agents. The availability of at least three effective agents allows for a choice of therapy to offer individual patients.
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PMID:Clinical pharmacology of the beta-blocking drugs: implications for the postinfarction patient. 613 42

Changes in the duration and size of the vulnerable period of the myocardium in the presence of respiratory changes were studied in acute experiments on rats. The limits of the vulnerable period were determined by directly stimulating the heart during ventilation via the enlarged respiratory dead space, during hyperventilation and during heart failure. In the control group (normal ventilation without enlargement of the dead space), the vulnerable period lasted 5.7 +/- 0.76 ms. During ventilation via the enlarged dead space, hypercapnic hypoxaemia developed and the vulnerable period was markedly prolonged (18.55 +/- 5.29 ms) by a shift of its inner limit to the left. Hyperventilation caused normoxic to hyperoxic hypocapnia and markedly reduced the duration of the vulnerable period (8.17 +/- 2.21 and 9.31 +/- 2.38 ms respectively). The vulnerable period lengthened the most in heart failure (25.46 +/- 3.93), mainly as a result of a shift of its outer limit. In all the experimental groups there was a shift of the vulnerable period to the right, which was fastest in hypercapnic hypoxaemia and slowest in hyperoxic hypocapnia. The administration of Inderal (3 mg/kg i.p.) or Arfonad (50 mg/kg i.p.) markedly shortened the vulnerable period during hypercapnic hypoxaemia (9.87 +/- 2.78 and 9.32 +/- 2.16 ms respectively), but did not block the shift. Lengthening of the vulnerable period during hypercapnic hypoxaemia was probably due to activation of sympathetic nerves via beta-adrenergic receptors.
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PMID:Changes in the vulnerable period of the rat myocardium during hypoxia, hyperventilation and heart failure. 643 69


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