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)

More and more patients with coronary heart disease (CAD) are admitted to intensive care units. The drugs used to treat these patients have various effects on the myocardium which must be known in order to avoid worsening the CAD. This review examines the metabolic effects on the myocardium of the most commonly used drugs in intensive care. The physiology of myocardial oxygen supply is first recalled with regard to the coronary circulation, myocardial oxygen extraction and consumption. Digitalis glycosides do not affect the coronary circulation, but the decrease myocardial oxygen consumption in patients with heart failure, mainly by lowering heart rate. Dihydropyridine calcium blockers (nifedipine, nicardipine) increase coronary blood flow, despite a decrease in arterial blood pressure. Their effects on myocardial oxygen consumption are mediated by a sympathetic reflex. Verapamil decreases the heart rate and myocardial inotropism, and is responsible for coronary vasodilation. The result is a decrease in myocardial oxygen consumption. Diltiazem and bepridil have almost similar effects: they decrease myocardial oxygen consumption and increase blood supply to the heart. It has been recently shown that verapamil was the most depressant calcium channel blocking agent, and that it resulted in the most important decrease in myocardial metabolism. Beta-blocking agents decrease myocardial metabolism, except those with an important intrinsic sympathomimetic activity, such as pindolol. Amiodarone can be considered as an alpha and beta blocking drug: its main effect is to counteract the effects of endogenous catecholamines on myocardial metabolism. The sympathomimetic amines (noradrenaline, adrenaline, isoprenaline, dopamine, dobutamine) increase, to different extents, myocardial oxygen consumption. Vasodilators, such as the nitrates or sodium nitroprusside, decrease cardiac filling pressures, and increase myocardial blood flow, thus lowering myocardial oxygen consumption. Phosphodiesterase inhibitors (amrinone, enoximone) have both an inotropic and a vasodilating effect. They decrease cardiac afterload, and increase blood supply to the myocardium; this compensates for the increase in myocardial oxygen consumption due to the increase in myocardial contractility. Because all the drugs used in intensive care have different effects on myocardial metabolism, their reasoned use should avoid an inappropriate increase in oxygen demand.
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PMID:[Changes in myocardial metabolism induced by drugs used during intensive care]. 197 Apr 63

Digitalis toxicity continues to be a problem for pediatric patients undergoing therapy with cardiac glycosides for heart failure or arrhythmias, as well as in accidental ingestions. In this article the previous use of digoxin-specific antibody Fab fragments to treat digitalis overdose or intoxication in children is reviewed. The case reports cited in the medical literature and the 57 pediatric cases gathered as a result of the multicenter clinical trial and postmarketing surveillance study reported here indicate that digoxin-specific antibody Fab fragments are effective in ameliorating signs of digitalis poisoning in children. Not only can Fab fragments rapidly eradicate potentially life-threatening arrhythmias and conduction defects, but they are also effective in treating hyperkalemia and other noncardiac manifestations of digitalis toxicity. In the small samples of patients studied to date, complications have been minimal and no allergic reactions to digoxin-specific Fab fragments have been observed. Recommendations for the management of digitalis intoxication in children are outlined.
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PMID:Results of multicenter studies of digoxin-specific antibody fragments in managing digitalis intoxication in the pediatric population. 199 16

Digitalis was discovered over two centuries ago and has been in everyday use for 100 years: however nowadays it is not considered to be the almost exclusive treatment of heart failure as it used to be with diuretic therapy. In the last decade, our understanding of the physiopathology of heart failure and the body's mechanisms of adaptation have improved and this has lead to the use of new molecules and a different approach to the problem of left ventricular failure. The classical contra-indications and precautions of use of digitalis have been studied in detail. The use of digitalis is contested especially in patients in sinus rhythm or with ischemic heart disease and it is used less often in adult cardiac emergencies. The competition between digitalis and vasodilator therapy is now very apparent in some situations; however, the choice between these two groups of drugs (as treatment of first intention or in association) has to be carefully considered in each individual case. The future of digitalis therapy lies without doubt in pediatric cardiology where it remains irreplaceable.
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PMID:[What are the indications for digitalis glycosides in the current treatment of cardiac insufficiency?]. 211 60

Given the absence of curative and preventive treatment of cardiac failure, symptomatic therapy is very important. In severe "non-ambulatory" cardiac failure, symptoms depend on the patient's resting hemodynamic status. This can be improved by diuretics, digitalis and vasodilators. A combination of these three drug groups is often required. However, the respective value of each group is unknown. Their use is limited by their specific undesirable secondary effects which are particularly common and severe at this advanced stage. Their effects on survival are unknown with the exception of angiotension converting enzyme inhibitors which have been shown to be beneficial. At the ambulatory stage symptoms occur on effort. In order to improve exercise capacity, the treatment chosen should increase the patient's reserve of cardiac output, limit the increase in pulmonary pressures, respect systemic arterial pressure, decrease venous pressure, dilate the muscular arterioles and improve oxygen extraction by skeletal muscle during physical exercise. Diuretics and angiotensin converting enzyme inhibitors can fulfill these objectives. The effects of the other vasodilators are more variable, due to a vasodilatation which is often inappropriate and to tachyphylaxis related to reflex activation of neuro-hormonal mechanisms. Digitalis and some vasodilator inotropic agents can improve symptoms and effort capacity. However, doubts over possible deleterious effects on mortality have to be cleared by large scale, controlled therapeutic trials. Symptoms of cardiac failure at the ambulatory stage and the effects of treatment on these symptoms should logically be evaluated by appropriate ergometric exercise stress testing, with measurement of the patient's maximum oxygen consumption whenever possible.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Symptomatic treatment of chronic cardiac insufficiency]. 212 11

The introduction of newer drugs with effective cardiovascular action to clinical practice has reduced dependence on digitalis compounds. This tendency has been further justified by statements to the effect that consistently satisfactory results can be obtained with alternative drugs; that the inotropic action of digitalis is not evident in patients with normal sinus rhythm; that digitalis increases myocardial oxygen consumption, and finally that the high incidence of intoxication should limit its use. The present article reviews the use of alternative agents; the inotropic effects of digitalis in the presence of sinus rhythm; the implications of the use of drugs augmenting contractility upon total myocardial performance and oxygen consumption, and the factors pertinent in favoring digitalis toxicity. Digitalis continues to be a useful agent in the treatment of heart failure, either in patients with atrial fibrillation or in sinus rhythm. It may well be administered in addition to diuretics, vasodilators or fosfodiesterase inhibitors. Digitalis toxicity can be minimized by considering factors enhancing such complication or conditions where its use is ineffective.
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PMID:[Controversies on digitalis]. 213 32

The value of digitalis in the treatment of heart failure with sinus rhythm remains controversial. It has been demonstrated that the moderate positively inotropic effect of digitalis observed after acute administration persists without tachyphylaxis. Digitalis produces symptomatic improvement, but its therapeutic quotient is low and its influence on mortality is unknown. This last point has become crucial, especially since some positively inotropic drugs increase ventricular rhythm disorders and are responsible for over-mortality among heart failure patients. In contrast, angiotensin-converting enzyme inhibitors reduce mortality in patients with severe heart failure. In short, digitalis is useful only in certain physiopathological types of heart failure where it is used electively and complements the action of angiotensin-converting enzyme inhibitors.
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PMID:[Role of digitalis derivatives in the treatment of cardiac insufficiency with sinusal rhythm]. 214 Jan 60

A 21 day old infant, diagnosed as ASD, VSD, and PDA, was scheduled for an emergency radical operation. After admission, she fell into cardiac failure and was treated with artificial ventilation and infusion of inotropic agents. Anesthesia was induced with fentanyl and maintained with continuous fentanyl infusion and chlorpromazine. Dopamine and dobutamine were administered before she underwent a cor-pulmonary by-pass. At the time of release of aortic clamping, her blood pressure went down and dopamine, dobutamine and isoproterenol were administered. After completion of the cor-pulmonary by-pass, tachy-arrhythmia and hypotension occurred. Digitalis and calcium did not reverse the condition. The thorax was reopened and BP rose. After 15 min, ventricular fibrillation occurred. Defibrillation was carried out, but the heart was arrested. Even with pacing and cardiac massage, cardiac contraction did not resume. However immediately on intravenous administration of PGE1, 40 ng.kg-1.min-1, the heart started to beat. The cause of recovery from cardiac arrest was speculated to be due to reuptake of intracellular Ca2+ by PGE1. We stress therefore, that during and after cor-pulmonary by-pass procedures, PGE1 infusion may be beneficial.
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PMID:[Recovery from cardiac arrest by prostaglandin E1 infusion during emergency open heart surgery]. 227 47

Controlled trials using modern methods of assessment in well-defined groups of patients have now convincingly demonstrated that digitalis is an effective and well-tolerated drug in patients with chronic heart failure who have left ventricular systolic dysfunction. These encouraging findings concerning digitalis, however, should not be construed to suggest that the drug should be used alone in the treatment of heart failure. Digitalis cannot adequately control the fluid retention seen in most patients with chronic heart failure; diuretics should be added to maintain sodium balance. Digitalis has not been shown to prolong life in chronic heart failure; converting-enzyme inhibitors should be added to reduce morbidity and mortality. All three drugs should be used together in the management of patients with this disorder.
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PMID:Does digitalis work in chronic heart failure? The end of a 200-year-old controversy. 248 86

1. Cardiac failure is a clinical syndrome of symptoms and signs, which can be confirmed by imaging or invasive haemodynamic techniques. It may be caused by systolic or diastolic dysfunction, but systolic dysfunction rarely occurs alone. It is important to ascertain the degree to which each contributes, and the precise aetiology of the condition, particularly in relation to surgically correctable lesions. 2. Non-pharmacological approaches including weight loss, salt restriction and lifestyle changes may be beneficial in some patients, and diuretics, which reduce the load on the heart, are the traditional baseline therapy. 3. Digitalis has been used where problems with contractility predominate, but its beneficial effect has been disputed, and expectations of improvement in patients in sinus rhythm should not be too high. 4. Vasodilators have been considered as the next line of treatment. Arteriolar dilators tend to increase cardiac output, but have little effect on pulmonary artery wedge pressure, and venodilators tend to have the opposite effect. Probably both actions are necessary and angiotensin converting enzyme (ACE) inhibitors, which have both, have proved effective in terms of symptoms and survival. 5. Various other inotropic agents have been tried. Phosphodiesterase inhibitors improve exercise tolerance, but may increase the probability of serious arrhythmias, already a significant cause of sudden death. beta 1-partial adrenoceptor agonists such as xamoterol have shown some promise, and anti-arrhythmic therapy has also been considered. 6. Drugs which prevent progression of myocardial damage would prove a great advance, and beta-adrenoceptor antagonists and calcium channel blockers appear to have considerable potential in this area.
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PMID:Treatment of congestive heart failure--state of the art and future trends. 257 53

Prognosis of heart failure patients remains poor and stimulates research of new active drugs and therapeutic improvements. Besides diuretic and vasodilating agents, the place of positive inotropic drugs remains to be defined. Long term benefit remains to be demonstrated for Milrinone, Enoximone and Digitalis. However, absence of benefit has been established with Amrinone and beta adrenoceptor agonists. Too many uncontrolled studies have complicated the accurate evaluation of efficacy of these positive inotropic drugs. Purpose of heart failure treatment remains to improve functional status without deterioration of myocardial fibers contractility. The respective roles of cAMP, gAMP and intracellular calcium concerning myocardial fiber longevity remains to be clarified.
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PMID:[Treatment of chronic heart failure with positive inotropic agents]. 257 55


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