Initial Drug Treatment - Systolic Dysfunction

The initial drug treatment of significant systolic dysfunction typically includes: angiotensin converting enzyme, or ACE, inhibitors, beta blockers and diuretics.

ACE inhibitors are vasodilators the decrease both preload and afterload. They improve survival and exercise capability and inhibit the process of remodeling.

Beta blockers block cardiac adreno-receptors and paradoxically improve ejection fraction through upregulation of adreno-receptors. They increase survival, reduce hospitalizations and improve symptoms.

Diuretics decrease preload.

Beta blocker therapy should be cautiously administered after contol of the patient's volume status. These agents may initially cause decompensation and should be started at a very low dose. They should be progressively titrated upward to a target dose.

Additional therapy may be considered in selected patients. Aldosterone antagonists have been shown to reduce hospitalization and death in class II-IV patients already on standard therapy including beta blockers. An alternative approach to inhibition of angiotensin II for patients who cannot tolerate ACE inhibitors is the use of angiotensin II receptor blockers (ARB). Unlike ACE inhibitors, they do not inhibit kinase and, therefore, are not associated with cough, a common side effect of ACE inhibitors. The combination of hydralazine and isosorbide dinitrate provides complementary vasodilating effects in patients who cannot tolerate ACE inhibitors or ARBs. It appears to have added benefit to ACE inhibitors and ARBs in patients of African descent. Digitalis improves symptoms without influencing mortality in patients with elevated filling pressures, or volume overload. Digitalis should be used in low doses, to keep digoxin levels less than one nanogram per milliliter. Excerise training should be considered for all stable patients on standard drug therapy, because it can lessen symptoms, increase exercise capacity and improve the quality of life

More intensive therapy for hospitalized patients with refractory congestive heart failure include the temporary use of intravenous agents. They may provide further afterload reduction with or without preload reduction and include IV nitroglycerin, nitroprusside and less commonly, B-type natriuretic peptide (BNP). Alternatively, intravenous inotropic drugs may be used to temporarily to boost the contractility of the left ventricle and include dobutamine, dopamine and milrinone. Biventricular pacing has also been shown to improve functional capacity, quality of life and survival in selected patients.