PATIENTS WITH MILD HEART-FAILURE WORSEN DURING WITHDRAWAL FROM DIGOXIN THERAPY

Objectives. We investigated whether patients with mild heart failure d ue to left ventricular systolic dysfunction were at risk of worsening during digoxin withdrawal. Background. Deterioration during digoxin wi thdrawal is often believed to be restricted to patients with moderate to severe clinical evidence of heart failure, To test this hypothesis, we studied the outcome of patients categorized by treatment assign me nt and a clinical signs and symptoms heart failure score in two rigoro usly designed clinical heart failure trials: the Prospective Randomize d Study of Ventricular Function and Efficacy of Digoxin (PROVED) and t he Randomized Assessment of Digoxin and Inhibitors of Angiotensin-Conv erting Enzyme (RADIANCE) trial. Methods. Potential differences in trea tment failure, left ventricular ejection fraction and exercise capacit y were evaluated in three groups of patients: those with mild heart fa ilure (score less than or equal to 2) who were withdrawn from digoxin (Dig WD Mild); those with moderate heart failure (score >2) who were w ithdrawn from digoxin (Dig WD Moderate); and patients who continued re ceiving digoxin regardless of heart failure score (Dig Cont). Results. Heart failure score at randomization did not predict outcome during f ollow-up in Dig Cont-group patients. Dig WD Mild group patients were a t increased risk of treatment failure and had deterioration of exercis e capacity and left ventricular ejection fraction compared with that i n Dig Cont group patients (all p < 0.01). Patients in the Dig WD Moder ate group mere significantly more likely to experience treatment failu re than patients in either the Dig WD Mild or Dig Cont group (both p < 0.05). Conclusions. Patients with systolic left ventricular dysfuncti on were at risk of clinical deterioration after digoxin withdrawal des pite mild clinical evidence of congestive heart failure. (C) 1997 by t he American College of Cardiology.