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Query: UMLS:C0018801 (heart failure)
 72,216 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In several studies the nitrate effects on central hemodynamics during less than 24 hours have been evaluated in heart failure. Higher doses than in angina have been used. A pronounced response is seen acutely. An attenuation has been reported after 12-24 hours. A relation to continuous (intravenous, transdermal) administration of nitroglycerin has been proposed, but it is not clear. During chronic treatment with ISDN a tolerance is not obvious within 12 weeks. The heart failure patient has a different neurohumoral situation compared to angina patients. This could be one reason for differences in tolerance development during nitrate therapy.
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PMID:Development of tolerance to nitrate therapy in chronic congestive heart failure. 353 80

Calcium-channel blockers are known to have depressant effects on atrioventricular (AV) nodal conduction and myocardial contractility. Because of these known depressant effects, bepridil hydrochloride, a new, long-acting, antianginal and antiarrhythmic calcium-channel blocker, was administered intravenously to patients without heart failure to determine acute hemodynamic effects. The patients studied had normal ventricular function, were without electrocardiographic conduction disturbances and were taking no drug except sublingual nitroglycerin for at least 24 hours before bepridil infusion. The study protocol included right- and left-sided cardiac catheterization with infusion of bepridil at 2 mg/kg for 15 minutes followed by 1 mg/kg for 15 minutes in 10 patients, and infusion of bepridil at 3 mg/kg for 15 minutes followed by 1 mg/kg for 15 minutes in 8 patients. Pressures, Fick cardiac output, resistances, left ventricular (LV) dP/dt, LV stroke work index and rate-pressure product of the left ventricle were monitored. There were no significant changes during bepridil infusion at either dose for cardiac output, systemic vascular and pulmonary vascular resistances, LV stroke work index, heart rate, arterial blood pressure and rate-pressure product. There was mild depression of LV dP/dt during bepridil infusion. Further, LV end-diastolic pressure, pulmonary capillary wedge pressure and pulmonary arterial pressures were significantly increased during bepridil infusion. There were no apparent changes in AV nodal or intraventricular conduction during bepridil infusion. We conclude that bepridil appears to be a safe drug for intravenous administration despite mild depression of myocardial function in patients with normal baseline hemodynamic function who are not receiving concomitant beta-blocker therapy.
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PMID:Hemodynamic effects of intravenous bepridil in patients with normal left ventricular function. 387 53

The dose requirements and duration of effect of transdermal nitroglycerin in patients with heart failure are not clearly established. In a first series of eight patients with chronic heart failure we gave transdermal nitroglycerin in incremental doses until pulmonary capillary wedge pressure fell at least 30% within 4 hr in three consecutive patients. Thus we found that a single dose of 60 mg/24 hr (120 cm2) was the minimal effective dose. Transdermal nitroglycerin or placebo was then given as a single application of 60 mg/24 hr in random double-blind fashion to 15 additional patients with heart failure (eight received transdermal nitroglycerin and seven received placebo), and hemodynamics were monitored for up to 24 hr. After administration of transdermal nitroglycerin, the control pulmonary capillary wedge pressure of 22 +/- 7 mm Hg fell by 6 +/- 6 mm Hg at 2 hr (p less than .05) and reached maximal reduction of 8 +/- 6 mm Hg (p less than .01) at 4 hr. The reduction in wedge pressure remained significant through 12 hr but was no longer statistically significant by 18 hr after administration of the drug. Transdermal nitroglycerin also significantly reduced pulmonary arterial and right atrial pressures as well as pulmonary vascular resistance from 4 through 12 hr but did not affect systemic hemodynamics. No significant hemodynamic changes occurred after administration of placebo. Thus transdermal nitroglycerin is an effective vasodilator in patients with heart failure, but a dose of at least 60 mg/24 hr is needed. Even with this dose, hemodynamic effects do not last beyond 18 hr, suggesting altered absorption or development of tolerance.
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PMID:Dose requirements and hemodynamic effects of transdermal nitroglycerin compared with placebo in patients with congestive heart failure. 392 Dec 79

Thirty-five patients with primary large-focal myocardial infarction (MI) were investigated, with mitral incompetence diagnosed in 19. All patients underwent clinical investigation, including electro-, phono- and echocardiography, and tetrapolar chest rheoplethysmography. Direct measurements of pulmonary arterial pressure were made in 11 patients. The investigations were carried out prior to, and at the peak of nitroglycerin action. It was shown that mitral regurgitation was associated with increased incidence and severity of heart failure during the acute stage of MI. Such patients showed low cardiac and stroke index values, a more marked overstrain of the left atrium and left ventricle, and high pulmonary arterial pressure. Intravenous administration of nitroglycerin improves intracardiac hemodynamics in acute MI, its effect being more pronounced in patients with mitral incompetence. Early and prolonged nitroglycerin treatment is indicated in cases of acute MI with mitral incompetence.
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PMID:[Use of nitroglycerin in acute myocardial infarct complicated by mitral insufficiency]. 392 52

Vasodilators have been widely used in recent years for the treatment of severe left ventricular failure (LVF). However, amongst these drugs, not all have the same therapeutic effects, but they differ from one another in molecular structures, cellular mechanisms, haemodynamic actions and modes of administration. A three tier classification is proposed with the single objective of facilitating the therapeutic choice: mechanism of action: this property distinguishes the alpha-blockers from the beta-2 sympathomimetics, calcium antagonists, angiotensin converting enzyme inhibitors and prostacyclin biosynthesis inducers. Some molecules such as hydralazine, whose mechanism of action remains unclear, cannot be classified in this way; haemodynamic effects: these effects can be used to distinguish vasodilators which act mainly on the venous sector from arterial and mixed vasodilators. The knowledge of the preferential site ol action of these molecules helps to adapt the choice of treatment to the initial haemodynamic profile of each patient; pharmacokinetics: these properties distinguish molecules active only by intravenous administration, better adapted for the treatment of acute LVF in the intensive care unit, from those active orally which can be used for long-term ambulatory therapy of chronic cardiac failure. Trinitrin and its derivatives occupy an intermediate position because of their relatively low bioavailability after oral administration: long-term administration is not always easy and may require special modes of administration (i.e. percutaneous). Vasodilators have been widely used in cardiac failure for about 5 years; the results of some medium term controlled therapeutic trials are now available and confirm the efficacy of these drugs but also define their limitations: variable therapeutic efficacy: the number of responders ranges from 30 to 60 p. 100 according to the molecule used.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Classification and principles of the use of vasodilators in the treatment of left ventricular insufficiency]. 392 8

On the basis of their own 5-year experience, the authors discuss the indications for, and limitations of, intravenous infusion of nitroglycerin (NTG). In 42 patients with postinfarction heart failure, NTG produced a significant reduction of left ventricular filling pressure, regardless of its initial value. In patients with normal or only slightly elevated left ventricular filling pressure, NTG caused a decrease in cardiac index and mean arterial pressure as well as, in the earliest phase of infusion, an increase in peripheral resistance. Similar trends were observed also in patients with markedly elevated left ventricular filling pressure if mean arterial blood pressure fell by more than 20%. Taking into consideration that the range of the effective doses was very wide (15-150 micrograms/min), the authors believe that intravenous NTG infusion is indicated mainly in cases of manifest heart failure and should be administered under strict control of the dosage and with careful monitoring of the therapeutic effects.
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PMID:Haemodynamic effects of nitroglycerin infusion in patients with postinfarction heart failure. 393 75

The effects of intravenous nitroglycerin (NTG), trimetaphan (TMP), and phentolamine (PTL) on pulmonary artery diastolic pressure (PADP), systemic arterial pressure (SAP), cardiac index (CI) and systemic vascular resistance (SVR) in patients (12 in each treated group) with chronic ischaemic heart failure are analyzed. Each group was divided into two subgroups according to the initial PADP taking into account the mean value in the whole group. A significant decrease in PADP (by 40%; p less than 0.001) was observed in the NTG-treated group, with no significant changes in CI and SVR except for patients with moderately elevated initial PADP, in whom SVR increased slightly in the early period of treatment, and CI decreased (by 25%; p less than 0.05). TMP and PTL reduced SVR (by 25 and 30% respectively; p less than 0.01) and increased CI irrespective of the initial PADP. TMP significantly decreased PADP in patients in whom its level was initially high. The results suggest that NTG is mainly a venodilating agent which should be used in patients with high PADP and normal or slightly decreased CI. PTL acts mainly by reducing SVR and increasing CI. TMP influences both PADP and SVR and is a drug of choice in patients with high or elevated PADP and low cardiac output.
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PMID:Vasodilator drugs in patients with chronic ischaemic heart failure. 393 74

Beta adrenergic blocking agents are effective antianginal agents and reduce the frequency of anginal attacks, nitroglycerin consumption, and improve exercise tolerance in patients with stable exertional angina pectoris. These drugs are effective in the management of exertional angina pectoris primarily due to their ability to block beta 1 receptors and thereby competitively blocking the effects of sympathetic stimulation (i.e. increase in myocardial oxygen demand) during exercise. In this report other pharmacological properties of these agents i.e. membrane stabilizing activity, intrinsic sympathomimetic activity and cardioselectivity are of little importance. Comparative studies with beta adrenergic blocking agents with different ancillary properties, utilizing intravenous preparations, acute single and multiple oral dosing and sustained oral therapy prescribed for several weeks or months, show that if used in equipotent doses all beta adrenergic blocking agents are equally effective antianginal agents. It should be recognized that therapy with these agents may precipitate heart failure or aggravate bronchospasm in susceptible patients. This can occur with cardioselective agents and with beta blockers which also have intrinsic sympathomimetic activity.
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PMID:Beta adrenergic blocking agents for exertional angina pectoris. 612 93

There is considerable interest in selecting the proper drug to preserve the ischemic myocardium, or twilight zone, in a patient with a recent myocardial infarction. Vasodilator therapy with an infusion of nitroprusside or phentolamine has been shown to improve left ventricular function by reducing both preload and afterload. Sublingual nitroglycerin as well as an infusion of nitroglycerin can also alleviate left ventricular failure in patients with an acute myocardial infarction. Similarly, chronic congestive heart failure patients, irrespective of the etiology, improve hemodynamically after an infusion of phentolamine, nitroprusside or hydralazine. Oral nitrates, phentolamine, and hydralazine have also been demonstrated to produce improvement in chronic heart failure patients. Recently data has become available on the effects of phentolamine, nitroglycerin and nitroprusside on cardiac conduction in man. However there is no information on the electrophysiological properties of hydralazine in man. The present study involving 12 human subjects was undertaken to determine what effect intravenously administered hydralazine has on the human conduction system.
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PMID:Electrophysiologic properties of hydralazine in man. 616 May 53

After in-vivo labeling of red blood cells with 99mTcO4, the radioactivity of different parts of the body is proportional to the regional blood volume. This technique allows the simultaneous registration of drug-induced changes of the local blood volume. We examined the influence of nitroglycerin on the blood volume distribution in patients with coronary artery disease (n = 10) and chronic heart failure (n = 8). Compared with the controls (n = 8) we observed in the nitroglycerin-groups a significant decrease of blood volume over the heart and the liver, whereas there was an increase of the blood volume over the extremities. It is pointed out that functional whole-body scanning is a useful radiological technique for the non-invasive study of pharmacologically caused changes of the local blood volume in man.
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PMID:[Functional scintigraphic blood pool study. A radiologic technic for non-invasive study of pharmacologically induced blood volume fluctuations]. 630 27


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