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

Seven patients with decompensated chronic heart failure and functional mitral regurgitation were studied before and during administration of nitroglycerin at a mean dose of 42 micrograms/min (range 20 to 90 micrograms/min). Forward aortic flow obtained by pulsed Doppler increased significantly from 35 +/- 8 to 45 +/- 9 ml/beat (p less than 0.001) and correlated well with the cardiac output measured by thermodilution technique (r = 0.8). Whereas regurgitant mitral volume calculated from the difference between echocardiographic total stroke volume and forward aortic flow decreased significantly from 19 +/- 9 to 3 +/- 3 ml/beat (p less than 0.001), peak velocity of mitral regurgitant flow increased from 4.1 +/- 0.9 to 4.4 +/- 1.0 m/sec (p less than 0.05). The decrease in effective mitral regurgitation area derived from a modified Gorlin formula average 80%. Accordingly, in patients with decompensated chronic heart failure and functional mitral regurgitation, nitroglycerin decreases mitral regurgitant area substantially, and thus almost abolishes mitral regurgitation despite an increase in systolic pressure gradient between left ventricle and atrium. Moreover, the increase in forward flow can be entirely accounted for by the reduction in mitral regurgitant flow.
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PMID:Dynamics of mitral regurgitation during nitroglycerin therapy: a Doppler echocardiographic study. 309 8

Nitroglycerin delivered by transdermal patch technology has been used in angina pectoris patients as well as in heart failure. In angina pectoris patients the plasma concentrations are low over the 24 hours. Effects can be found especially during the first 12 hours after application of the drug even during steady state conditions. The effect of the drug wanes after 24 hours and some studies suggest reduced effect when the patches have been applied for seven to 14 days. The attenuated effects have been claimed to be due to tolerance. Tolerance is, however, never absolute and in other studies this phenomenon is not shown. Furthermore, rebound phenomena may develop when nitroglycerin therapy is withdrawn. The optimal doses and schemes for nitroglycerin administration thus remain to be clarified.
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PMID:Tolerance development during transdermal administration of nitroglycerin in angina pectoris. 309 45

Timing of coronary artery bypass grafting after acute myocardial infarction (MI) is controversial, especially if myocardial function is depressed. Early coronary artery bypass grafting may result in reperfusion injury causing cardiac failure. Delay, however, may risk a second ischemic event. This study was performed to determine if four preoperative factors--time after MI, ejection fraction, ischemia (need for intravenous administration of nitroglycerin), and failure (need for inotropic support)--independently predict postoperative cardiac failure. Postoperative failure was defined as the need for inotropic support or intraaortic balloon pumping. The study group consisted of 145 patients who underwent isolated coronary artery bypass grafting between January, 1980, and July, 1985, within 4 weeks of an acute MI. Postoperatively 38 patients (26%) had cardiac failure. Five patients, all of whom had postoperative cardiac failure, died. Univariate and stepwise logistic regression analyses showed preoperative failure (p = .0001), ejection fraction less than 45% (p = .002), and preoperative ischemia (p = .02) were predictors of postoperative cardiac failure. Time after MI was not found to be an independent predictor (p = .96). We conclude that if ischemia or threatening coronary anatomy is present early after MI and clinical improvement is not occurring, operative intervention should be strongly considered at that time, as it does not appear that delay itself reduces the risk of cardiac failure and may risk a second ischemic event.
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PMID:Determinants of cardiac failure after coronary bypass surgery within 30 days of acute myocardial infarction. 309 99

The haemodynamic effect of transdermal nitroglycerin treatment with Deponit 10 was investigated in 10 patients with chronic cardiac failure due to coronary artery disease (8 patients) or congestive cardiomyopathy (2 patients). The patients had elevated mean pulmonary artery (PA) and pulmonary capillary wedge pressures (PC) at rest (32.1 +/- 5.9 and 24.1 +/- 6.6 mm Hg). Heart rate (87 +/- 10), arterial blood pressure (133 +/- 20/77 +/- 8 mm Hg) and cardiac index (3.73 +/- 0.85 l/min/m2) were in the normal range. During treatment with Deponit 10 mean PA and PC pressures decreased significantly (p less than 0.01) to 25.5 +/- 6.3 and 18.1 +/- 6.4 mm Hg, respectively. The effect was seen within 1 hour after application of the transdermal therapeutic system and reached its nadir after 2 hours. PA and PC pressures remained significantly below control for 12-16 hours. Heart rate, arterial blood pressure and cardiac index were not changed. After removal of the patch 4 patients showed a rebound haemodynamic deterioration. Their mean PA pressure rose by more than 4 mm Hg above the respective control values. These patients had the highest control PA pressures of the group studied (37.5 +/- 2.4 mm Hg). Thus, transdermal nitroglycerin treatment with Deponit 10 reduces cardiac preload in patients with congestive heart failure for 12-16 hours, whereas cardiac afterload remains unaffected. After removal of the patch a rebound phenomenon can occur especially in patients with severe cardiac failure.
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PMID:[Hemodynamic effect and duration of action of Deponit 10 in patients with congestive heart insufficiency]. 309 88

Transdermal systems for delivery of nitroglycerin have been shown to provide sustained blood levels of the drug for at least 24 hours. Investigations of hemodynamic effects of transdermal nitroglycerin in patients with heart failure have demonstrated a transient reduction in pressure lasting less than the expected 24 hours. These findings could be due to the development of circulatory tolerance to the vasodilatory effects of nitroglycerin or to insufficient drug dosing. In the present study, we compared the hemodynamic effects of the first and the second doses of high dose (120 mg) transdermal nitroglycerin given 24 hours apart in 11 responders (greater than or equal to 20% reduction in mean pulmonary artery wedge pressure lasting greater than or equal to 2 hours). Initiation of nitroglycerin therapy resulted in a significant reduction in mean right atrial pressure lasting for 14 hours and in a reduction in mean pulmonary artery and mean pulmonary artery wedge pressures lasting 24 hours. After administration of the second dose, mean right atrial pressure at 2 hours (9 +/- 5 versus 7 +/- 4 mm Hg), 4 hours (8 +/- 5 versus 6 +/- 4 mm Hg) and 8 hours (8 +/- 5 versus 6 +/- 3 mm Hg) was higher than after the first dose (p less than 0.05). Both mean pulmonary artery and mean pulmonary artery wedge pressures were significantly higher after the second nitroglycerin dose.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Early tolerance to hemodynamic effects of high dose transdermal nitroglycerin in responders with severe chronic heart failure. 310 35

The effectiveness of nitroglycerin in the treatment of acute heart failure was investigated in 100 patients with myocardial infarction. It was found that nitroglycerin has marked advantages in comparison with cardiac glycosides both as regards its effectiveness and as regards the character of its action on the haemodynamics and the state of the periinfarction zone. In most patients (78%), a favourable effect was attained with intravenous nitroglycerin administration and with additional intake in the form of tablets. Clinical improvement was preceded by normalization of pulmonary artery pressure. Uninterrupted nitroglycerin administration was terminated after normalization and stabilization of haemodynamics. The results showed that with monitoring haemodynamics nitroglycerin can be administered also in haemodynamic disorders, which occur in the early period of cardiogenic shock.
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PMID:Use of nitroglycerin in the treatment of acute heart failure and cardiogenic shock in patients with myocardial infarction. 310 5

Sustained therapy with nitroglycerin (NTG) has been reported to provoke the development of early tolerance. Because continuous intravenous NTG infusion is commonly used in patients with coronary artery disease and heart failure, we evaluated the incidence of early tolerance developed within the first 24 hr of therapy in 31 responders to NTG. After documentation of response to NTG, defined as a 10 mm Hg or greater or a 30% or greater reduction in mean pulmonary arterial wedge pressure (PAWP), 16 patients were blindly, randomly assigned to receive placebo and 15 patients were continued on same-dose NTG. Both groups showed an identical fall in PAWP at peak NTG titration (11 +/- 4 mm Hg). Discontinuation of NTG in the placebo group resulted in a rapid increase in PAWP to levels not significantly different from baseline (19 +/- 5 mm Hg at 2 hr vs 23 +/- 6 mm Hg at baseline; p = NS). In the NTG group, PAWP fell from 27 +/- 9 to 14 +/- 7 mm Hg, was 16 +/- 9 mm Hg at 2 hr (p less than .05 vs baseline), and continued to be significantly lower than baseline for 8 hr; however, due to attenuation of effect, PAWP values at 12, 20, and 24 hr were not significantly different from placebo or baseline values.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Incidence of early tolerance to hemodynamic effects of continuous infusion of nitroglycerin in patients with coronary artery disease and heart failure. 311 64

To evaluate possible mechanisms underlying the development of nitrate tolerance, we treated 35 patients who had severe chronic heart failure with a prolonged (48-hour) intravenous infusion of nitroglycerin (6.4 micrograms per kilogram of body weight per minute) given either continuously or intermittently (12-hour infusions separated by intervals of 12 hours). Intravenous nitroglycerin produced immediate hemodynamic benefits in all patients, but the magnitude of this improvement was greatly diminished after 48 hours of continuous therapy with the drug. This attenuation was accompanied by cross-tolerance to oral isosorbide dinitrate and by an increase in heart rate, plasma renin activity, and body weight. In contrast, intermittent therapy with intravenous nitroglycerin was not associated with a loss of hemodynamic efficacy or cross-tolerance to oral nitrates and was not accompanied by changes in neurohormonal activity or body weight. In eight patients in whom nitrate tolerance developed during continuous intravenous therapy, the administration of the sulfhydryl-containing compound N-acetylcysteine (200 mg per kilogram orally) restored the hemodynamic state toward that observed at the start of the infusion of nitroglycerin (partial reversal of tolerance). In contrast, N-acetylcysteine had little hemodynamic effect in patients who were not receiving nitroglycerin. These data support the hypothesis that neurohormonal activation and depletion of sulfhydryl groups may interact to cause the loss of hemodynamic efficacy that occurs during prolonged treatment with intravenous nitroglycerin in patients with heart failure. Evaluation of the suggested role of sulfhydryl depletion in the development of tolerance will, however, require direct studies of vascular tissue.
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PMID:Prevention and reversal of nitrate tolerance in patients with congestive heart failure. 311 37

The results of prolonged infusion treatment with Trinitrosan and Isoket of 29 patients with acute myocardial infarction and unstable angina pectoris are reported. The drug action on the anginal syndrome, accompanying cardiac failure, heart rate and arterial tension is analysed. The action on the dynamic of enzyme activity and of the electrocardiograms during the treatment is compared with a control group of healthy persons. The results show full therapeutic efficacy in relation to the anginal syndrome and cardiac failure without any other medication in 1/2 of the patients; a partial antianginal effect is found in 1/4 of the patients treated. The examinations did not show any favourable action of the drugs on the enzymes and ECGs followed up in dynamics. The nitrites in the doses applied show no negative action on the heart rate and arterial tension and no special hemodynamics control is required.
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PMID:[Infusion treatment with nitrites of patients with acute myocardial infarct and unstable angina pectoris]. 311 74

In a double-blind crossover study, the haemodynamic effects of nitroglycerin discs were compared with placebo in 9 patients with severe chronic congestive heart failure. Hourly measurements were made throughout 24 hours for the placebo and the active treatment; the first 6 hours were used as a dose titration phase to achieve at least a 5 mmHg decrease in pulmonary arterial diastolic pressure. Active treatment, requiring 30 mg of nitroglycerin in most patients, produced a significant improvement in the cardiac index compared with placebo, as assessed from the end of the dose titration period to the 24th hour. Values determined as baseline, as the average from hour 7 to 24, and at the 24th hour for active discs were 2.3, 2.5 and 2.6 litres/min/m2, whereas for the placebo they were 2.3, 2.2. and 2.2 l/min/m2, respectively. Heart rate remained unchanged during the study, though mean systemic arterial blood pressure and vascular resistance were lower during active treatment. Right atrial and pulmonary arterial pressures did not change. In conclusion, nitroglycerin discs decrease afterload and improve cardiac performance over 24 hours in patients with heart failure.
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PMID:Increase of cardiac output by afterload reduction in patients with severe congestive heart failure using nitroglycerin discs. A double-blind placebo-controlled haemodynamic study. 311 55


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