Implantable Cardioverter Defibrillator Therapy in Patients with Acute Decompensated Heart Failure with Reduced Ejection Fraction: An Observation from the KCHF Registry

Background: It remains unclear the clinical characteristics and prognosis of implantable cardioverter defibrillator (ICD) on prevention for sudden cardiac death (SCD) in Japanese patients with acute decompensated heart failure (ADHF) and reduced left ventricular ejection fraction (LVEF). We investigated the prevalence, clinical characteristics, and clinical outcomes in a contemporary large-scale Japanese ADHF registry. Methods: Among the consecutive 3785 patients hospitalized for ADHF and discharged alive in the Kyoto Congestive Heart Failure registry, we identified 1409 patients with reduced LVEF (ICD: N = 115, non-ICD: N = 1294). Results: Patients in the ICD group were younger (69.3 +/- 12.9/74.2 +/- 13.6 years; p < 0.001), more likely to be men (84%/65%), and more often had a history of heart failure hospitalization (70%/36%; p = 0.001), cardiomyopathy as the underlying heart disease (51%/27%; p < 0.001), and previous serious ventricular arrhythmia (57%/3.8%; p < 0.001), and had lower LVEF (25.4 +/- 7.4%/29.5 +/- 6.9%; p < 0.001), and estimated glomerular filtration rate (43.0 +/- 19.7/47.8 +/- 23.4 mL/min/1.73m2; p = 0.04) than those in the non-ICD group. The cumulative 1-year incidence of the primary arrhythmic composite endpoint of SCD, arrhythmic death, or resuscitated cardiac arrest trended to be lower in the ICD group than in the non-ICD group (0.0% versus 3.4%, p = 0.053), and the lower adjusted risk of the ICD group relative to the non-ICD group was significant for the primary arrhythmic endpoint (HR 0.10, 95% CI, 0.01-0.53; p = 0.003). However, there were no differences in the cumulative incidences of all-cause death between the ICD and non-ICD groups (17.3% versus 17.5%, p = 0.68), and the adjusted risk of the ICD group relative to the nonICD group remained insignificant for all-cause death (HR, 0.85; 95%CI, 0.52-1.36, p = 0.51). Conclusions: This study elucidated the real-world features of ADHF patients between those with ICD and those without. ICD use in patients with ADHF and reduced LVEF as compared with non-ICD use was associated with significant risk reduction for arrhythmic events, but not for mortality. (c) 2020 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study revealed that the use of ICD in Japanese patients with ADHF and reduced LVEF was associated with a significant reduction in the risk of arrhythmic events, but did not impact mortality rates.