Patients with EF >35% at the time of primary prevention ICD generator replacement continue to be at significant risk for appropriate ICD therapy (5% per year vs 12% for EF ≤35%; HR 3.57, P=0.001).
Cohort (n=253)
Yes
Does recovered EF > 35% at the time of ICD generator replacement predict a lower risk of appropriate ICD therapy compared to persistently reduced EF ≤ 35% in primary prevention patients without prior therapies?
Patients with a primary prevention ICD and no previous therapy who have recovered EF >35% at generator replacement remain at significant risk for appropriate ICD therapy (5% per year), supporting continued ICD replacement in this population.
Effect estimate: HR 3.57
Absolute Event Rate: 5% vs 12%
p-value: p=0.001
BACKGROUND: The effectiveness of implantable cardioverter-defibrillators (ICDs) for primary prevention of sudden death in patients with an ejection fraction (EF) ≤ 35% and clinical heart failure is well established. However, outcomes after replacement of the ICD generator in patients with recovery of EF to >35% and no previous therapies are not well characterized. METHODS AND RESULTS: Between 2001 and 2011, generator replacement was performed at 2 tertiary medical centers in 253 patients (mean age, 68.3 ± 12.7 years; 82% men) who had previously undergone ICD placement for primary prevention but subsequently never received appropriate ICD therapy. EF had recovered to > 35% in 72 of 253 (28%) patients at generator replacement. During median (quartiles) follow-up of 3.3 (1.8-5.3) years after generator replacement, 68 of 253 (27%) experienced appropriate ICD therapy. Patients with EF ≤ 35% were more likely to experience ICD therapy compared with those with EF > 35% (12% versus 5% per year; hazard ratio, 3.57; P = 0.001). On multivariable analysis, low EF predicted appropriate ICD therapy after generator replacement (hazard ratio, 1.96 1.35-2.87 per 10% decrement; P = 0.001). Death occurred in 25% of patients 5 years after generator replacement. Mortality was similar in patients with EF ≤ 35% and > 35% (7% versus 5% per year; hazard ratio, 1.10; P = 0.68). Atrial fibrillation (3.24 1.63-6.43; P 35% at the time of generator replacement, these patients continue to be at significant risk for appropriate ICD therapy (5% per year). These data may inform decisions on ICD replacement.
Madhavan et al. (Tue,) conducted a cohort in Primary prevention of sudden cardiac death (n=253). ICD generator replacement with EF > 35% vs. ICD generator replacement with EF ≤ 35% was evaluated on Appropriate ICD therapy (HR 3.57, p=0.001). Patients with EF >35% at the time of primary prevention ICD generator replacement continue to be at significant risk for appropriate ICD therapy (5% per year vs 12% for EF ≤35%; HR 3.57, P=0.001).