In this article, we will discuss the Role of Digitalis in the Management of Heart Failure. So, let’s get started.
To improve myocardial contractility: It is a cardiac glycoside acts by increasing the force of contraction (positive inotropic action), delays conduction through AV node, slows the heart rate (negative chronotropic effect) and increases the excitability of heart, hence, is a proarrhythmic agent also.
It is useful in CHF (grade III and IV) to improve ventricular emptying i.e. it improves cardiac output, ejection fraction, reduces end diastolic pressure, thus improves symptoms resulting from pulmonary vascular congestion. It is most beneficial in patients in whom myocardial contractility is impaired secondary to chronic ischemic heart disease, hypertensive heart disease or when valvular or congenital heart disease imposes an excessive volume overload. It is not useful in CHF due to high output states (thyrotoxicosis, beri beri, cor pulmonale) or CHF due to stenotic valvular lesions or myocarditis. However, digoxin is used to slow ventricular rate in atrial fibrillation or to convert atrial fibrillation to atrial flutter due to any cause. Digital Investigation Group (DIG) trial though have found no benefit or harm with digitalis, hence, recommends its use in CHF in patients who remain symptomatic in spite of adequate volume control.
Dose and route: The digoxin is used orally in lower doses i.e. 0.5 mg followed by oral maintenance dose of 0.125 mg to 0.25 mg daily. In chronic heart failure maintenance dose may be given thrice or five times a week.