Table 1. Randomized Trials of ICD Therapy to Prevent Sudden Cardiac Death in Patients with Left Ventricular Systolic Dysfunction.

Trial	Year	N (1)	Inclusion Criteria (2)
MADIT-II (3)	2002	742	Prior myocardial infarction NYHA I-III symptoms at enrollment LVEF≤0.30 Optimal medical therapy
SCD-HeFT (4)	2005	829	Chronic stable heart failure NYHA II-III symptoms LVEF ≤0.35 LSVD of ischemic or non-ischemic etiology Optimal medical therapy

Notes: (1) number of patients randomized to ICD therapy; (2) enrolled patients without a history of sudden cardiac death or syncope attributed to ventricular arrhythmias; (3) randomized comparison of ICD therapy with medical therapy; (4) randomized comparison of ICD therapy with medical therapy or medical therapy plus amiodarone.

Abbreviations: LVEF=left ventricular ejection fraction; LVSD=left ventricular systolic dysfunction; NYHA=New York Heart Association; VT=ventricular tachycardia