Precipitation of heart failure following sudden withdrawal of hydralazine.

Sudden withdrawal of oral therapy with hydralazine for reduction of afterload in a patient precipitated severe congestive heart failure. Signs of metabolic encephalopathy evolved due to low cardiac output. Reinstitution of therapy with hydralazine resulted in prompt improvement in cardiac and neurologic status. This case underscores the need for careful follow-up of such patients and argues against sudden withdrawal of vasodilator therapy.