55 Effect of Aldosterone Antagonist on Ventricular Arrhythmias and Appropriate Implantable Cardiovertor Shocks in Patients With Congestive Cardiomyopathy:

Abstract

BackgroundAdministration of aldosterone antagonists among patients with congestive heart failure (CHF) reduces total mortality, sudden cardiac death and frequency of ventricular arrhythmias. Effectiveness of spironolactone, an aldosterone antagonist, in reduction of implantable cardiovertor-defibrillator (ICD) shocks due to ventricular arrhythmia among patients with CHF has never been established. We sought to establish that spironolactone reduces the frequency of total ICD shocks, ventricular tachycardia (VT), ventricular fibrillation (VF) and non-sustained VT (NSVT).MethodsAll patients who underwent ICD implantation between 2000 and 2002 and were receiving spironolactone due to CHF were compared with matched group of control subjects with CHF and ICD, who were not receiving spironolactone. Kruskal-Wallis test was performed for the means of ICD shocks, number of VT, VF and NSVT episodes per month, in the study and control group. P value was calculated for each variable.ResultsBaseline characteristics were similar in the treatment and control groups: age (64.61 vs. 67.54 yrs; p = 0.29), LVEF (21.3% vs. 24.7%; p = 0.06), CAD (82.1% vs. 94%; p = 0.22), use of beta blockers (85.7% vs. 63.8%, p = 0.08), amiodarone (21.43% vs. 30.56%, p = 0.56) and ACE inhibitors (75% vs. 61.1%, p = 0.29) respectively. The results are given in the Table: ConclusionsSpironolactone reduced the frequency of total ICD shocks, VT and NSVT but not VF among ICD recipients with CHF.