In patients with NYHA class II or III CHF and LVEF of 35 percent or less, amiodarone has no favorable effect on survival, whereas single-lead, shock-only ICD therapy reduces overall mortality by 23 percent.

Patients with small social networks had an elevated risk of mortality, but this greater risk was not attributable to confounding with disease severity, demographics, or psychological distress. These findings have implications for mechanisms linking social isolation to mortality and for the application of psychosocial interventions.