Abstract 1877: Patient Misperceptions about the Survival Benefit of Implantable Defibrillators for Primary Prevention of Death in Heart Failure
Introduction: Broader indications for implantable cardioverter-defibrillators (ICDs) in primary prevention of sudden death may impact >1 million patients with heart failure (HF) though most will die of causes not preventable by ICDs. We examined patient perceptions about the effect of ICDs on survival.
Methods: Pts with LVEF <35% and HF symptoms, without prior VT/VF, cardiac arrest, or syncope, were chosen from 2 referral centers to approximate the SCD-HeFT population in which ICDs saved 7.2 lives per 100 during 5 years. Consent was obtained prior to a questionnaire asking pts to anticipate lives saved by ICDs and circumstances under which they might turn off the device. Responses were compared using Fisher’s Exact Test for proportional differences.
Results: Of 104 pts surveyed, 65% had ICDs, 52% had HF >5yrs, and 37% were NYHA Class III. Mean LVEF was 21% and peak VO2 14 ml/kg/min. Asked about magnitude of benefit, 54% thought ICDs would save ≥50 lives per 100 over 5 years and 97% overestimated the number of lives saved compared to SCD-HeFT. [Figure⇓] Estimates did not differ between pts with and without ICD (p=0.46). More ICD recipients believed the device would definitely save their own life than patients without an ICD (67% vs. 16%, p<0.0001). Despite the ease of programming defibrillation off, 70% of ICD recipients indicated they would keep the ICD on if dying of cancer, 55% would keep it on with daily shocks, and none would inactive defibrillation even for constant dyspnea at rest.
Conclusion: HF pts overestimate the survival benefits of ICDs for primary prevention and are reluctant to turn them off. Their education should include candid discussion about the limitations of ICD benefit.