Heart failure, chronic digoxin

In eight patients with chronic heart failure taking digoxin 0.25 mg/day, isosorbide dinitrate 10 mg tds caused only a small increase in (15%) and had no effect on the mean steady-state serum concentration or AUC (241). 

In a crossover study in 8 patients with chronic heart failure given digoxin 250 micrograms daily for 20 days with isosorbide dinitrate 10 mg three times daily for the last 10 days, there was no change in the mean steady-state concentration, AUC or half-life of digoxin. ... 

EF less than 40%, chronic heart failure (CHF) o Digoxin... 

Digoxin-like immunore active substances (found in patients with chronic heart failure, end stage renal disease, liver disease, or third trimester of pregnancy) may cross-react with certain digoxin immunoassays and may result in a false elevation of levels... 

Atrial fibrillation Peak digoxin body stores larger than the 8 to 12 mcg/kg required for most patients with heart failure and normal sinus rhythm have been used for control of ventricular rate in patients with atrial fibrillation. Titrate doses of digoxin used for the treatment of chronic atrial fibrillation to the minimum dose that achieves the desired ventricular rate control without causing undesirable side effects. Data are not available to establish the appropriate resting or exercise target rates that should be achieved. 

In patients with chronic heart failure, the use of digoxin and beta blockers is typically sufficient to control heart rates, and the combination of digoxin with carvedilol has been shown to provide better overall rate control than either of them used alone in heart failure patients [42]. However, if the patient is either intolerant of beta blockers or they fail to... 

In patients with left ventricular dysfunction but no edema, an ACE inhibitor should be used first. Several large studies have showed clearly that ACE inhibitors are superior to both placebo and to vasodilators and must be considered, along with diuretics, as first-line therapy for chronic heart failure. However, ACE inhibitors cannot replace digoxin in patients already receiving the drug because patients withdrawn from the cardiac glycoside deteriorate while on ACE inhibitor therapy. 

Digoxin Na +, K+ ATPase inhibition results in reduced Ca2+ expulsion and increased Ca2+ stored in sarcoplasmic reticulum Increases cardiac contractility cardiac parasympathomimetic effect (slowed sinus heart rate, slowed atrioventricular conduction) Chronic symptomatic heart failure rapid ventricular rate in atrial fibrillation Oral, parenteral duration 36-40 h Toxicity Nausea, vomiting, diarrhea cardiac arrhythmias... 

Dec GW Digoxin remains useful in the management of chronic heart failure. Med Clin North Am 2003 87 317. [PMID 12693728]... 

Packer M, Gheorghiade M, Young JB, et al. Withdrawal of digoxin from patients with chronic heart failure treated with angiotensin-converting-enzyme inhibitors. RADIANCE Study, N Engl J Med 1993 329 1-7. 

Examples of specific drugs used in the treatment of chronic heart failure include digitalis glycosides (e.g., digoxin, positive inotropic agent), diuretics (hydrochlortiazide and furosemide), and vasodilators (nitrates such as nitroglycerin, ACE inhibitors, such as captopril, and hydralazine). 

Beta-adrenoceptor blockers. The realisation that the coiuse of chronic heart failure can be adversely affected by activation of the renin-angiotensin-aldosterone and sympathetic nervous systems led to exploration of possible benefit from P-adrenoceptors in a condition where, paradoxically, such drugs can have an adverse effect. Clinical trials have, indeed, shown that bisoprolol, carvedilol or metoprolol lower mortality and decrease hospitalisation when added to diuretics, digoxin and an ACE inhibitor (see below). 

Lindsay SJ, Kearney MT, Prescott RJ, Fox KA, Nolan J. Digoxin and mortality in chronic heart failure. UK Heart Investigation. Lancet 1999 354(9183) 1003. 

Mahgoub AA, El-Medany AH, Abdnlatif AS. A comparison between the effects of diltiazem and isosorbide dinitrate on digoxin pharmacodynamics and kinetics in the treatment of patients with chronic ischemic heart failure. Saudi Med J 2002 23(6) 725-31. 

Recent studies demonstrate that cardiac resynchronization therapy (CRT) offers a promising approach to selected patients with chronic heart failure. Delayed electrical activation of the left ventricle, characterized on the ECG by a QRS duration that exceeds 120 ms, occurs in approximately one-third of patients with moderate to severe systolic heart failure. Since the left and right ventricles normally activate simultaneously, this delay results in asynchronous contraction of the left and right ventricles, which contributes to the hemodynamic abnormalities of this disorder. Implantation of a speciahzed biventricular pacemaker to restore synchronous activation of the ventricles can improve ventricular contraction and hemodynamics. Recent trials show improvements in exercise capacity, NYHA classification, quality of life, hemodynamic function, and hospitalizations. A device that combined CRT with an implantable cardioverter-defibrillator (ICD) improved survival in addition to functional status. CRT is currently indicated only in NYHA class ni-IV patients receiving optimal medical therapy (ACE inhibitors, diuretics, -blockers, and digoxin) and... 

Adverse Effects. Digoxin can produce a variety of cardiac and noncardiac adverse effects, but it is usually well tolerated by most patients (Table 14-11). Noncardiac adverse effects frequently involve the central nervous system or gastrointestinal system but also may be nonspeciflc (e.g., fatigue or weakness). Cardiac manifestations include numerous different arrhythmias that are believed to be caused by multiple electrophysio logic effects (see Table 14-11). Cardiac arrhythmias may be the flrst evidence of toxicity in a patient (before any noncardiac symptoms occur). Rhythm disturbances are of particular concern because patients with chronic heart failure are aheady at increased risk for sudden cardiac death presumably owing... 

Gheorghiade M, Hall VB, Jacobsen G, et al. Effects of increasing maintenance doses of digoxin on left ventricular function and neurohormones in patients with chronic heart failure treated with diuretics and angiotensinconverting enzyme inhibitors. Circulation 1995 92 1801-1807. 

A patient who has been taking digoxin for several years for chronic heart failure is about to receive atropine for another condition. A common effect of digoxin (at therapeutic blood levels) that can be almost entirely blocked by atropine is (A) Decreased appetite... 

Drugs proved to reduce mortality in chronic congestive heart failure include all of the following EXCEPT (A) Captopril Carvedilol Digoxin Enalapril Spironolactone... 

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