ClinicalHeart FailureImaging modality for left ventricular ejection fraction estimation and effect of implantable cardioverter-defibrillator on mortality in patients with heart failure
Introduction
Sudden cardiac death is the most common mode of death for patients with heart failure with reduced ejection fraction (HFrEF).1,2 National guidelines recommend an implantable cardioverter-defibrillator (ICD) in patients with HFrEF with left ventricular ejection fraction (LVEF) ≤35% but do not recommend any specific imaging modality to determine LVEF.3,4 Two-dimensional echocardiography (2DE) and radionuclide ventriculography, also known as multigated acquisition radionuclide ventriculography (MUGA), are 2 commonly used noninvasive imaging approaches that use different mechanisms to estimate LVEF. Less is known about whether the effect of ICD on mortality varies between the 2 noninvasive imaging modalities used to estimate LVEF, the examination of which was the objective of the present study.
Section snippets
Source of data and study patients
The present analysis is based on a public use copy of data of the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) sponsored by the National Heart, Lung, and Blood Institute, the details of the rationale, design, and results of which have been previously reported.5 SCD-HeFT was a prospective, randomized, placebo-controlled trial comparing the effect of amiodarone or ICD on all-cause mortality in patients with chronic HFrEF (LVEF ≤35%) receiving conventional heart failure therapy. The
Baseline characteristics
The baseline characteristics of patients receiving ICD or placebo are summarized in Table 1. Of the 971 patients whose LVEF was estimated using 2DE, 486 were randomized to placebo and 485 were randomized to ICD. These patients had a mean age of 59 and 60 years, respectively, and both groups had a mean LVEF of 24% (Table 1). In contrast, of the 415 patients whose LVEF was estimated using MUGA, 208 were randomized to placebo and 207 were randomized to ICD. These patients had a mean age of 60 and
Discussion
The findings from our post hoc analyses of the SCD-HeFT data demonstrate that the effect of ICD in the subgroup of patients whose LVEF was estimated using the noninvasive imaging modalities of 2DE or MUGA is similar to that observed in the original trial. Furthermore, we demonstrate that there is no evidence of heterogeneity of the associations of ICD with all-cause and cause-specific cardiac mortalities between patients in the 2 noninvasive imaging modality groups. To our knowledge, this is
Conclusion
The findings of the present post hoc analysis of the SCD-HeFT data demonstrate that there is no evidence of heterogeneity in the effect of ICD on mortality in patients with HFrEF regardless of whether 2DE or MUGA was used to measure LVEF to determine the eligibility for the device.
References (13)
- et al.
Mode of death in advanced heart failure: the Comparison of Medical, Pacing, and Defibrillation Therapies in Heart Failure (COMPANION) trial
J Am Coll Cardiol
(2005) - et al.
Limitations in the current screening practice of assessing left ventricular ejection fraction for a primary prophylactic implantable defibrillator in southern Ontario
Can J Cardiol
(2010) - et al.
Prognostic value of LGE-CMR in HCM: a meta-analysis
JACC Cardiovasc Imaging
(2016) Disrupting the approach to sudden cardiac death: from vulnerable ejection fraction to vulnerable patient
Circulation
(2018)- et al.
2015 ESC Guidelines for the management of patients with ventricular arrhythmias and the prevention of sudden cardiac death: The Task Force for the Management of Patients with Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death of the European Society of Cardiology (ESC). Endorsed by: Association for European Paediatric and Congenital Cardiology (AEPC)
Eur Heart J
(2015) - et al.
2017 AHA/ACC/HRS Guideline for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death
Circulation
(2018)
Cited by (0)
Funding Sources: Dr Ahmed was in part supported by grants from the Department of Veterans Affairs (I01HX002422).
Disclosures: Dr Fonarow reports consulting with Abbott, Amgen, AstraZeneca, Bayer, Cytokinetics, Edwards, Janssen, Medtronic, Merck, and Novartis. None of the other authors report any conflicts of interest related to this manuscript. The content is solely the responsibility of the authors and does not necessarily represent the official views of the Department of Veterans Affairs.
- 1
Equal contribution.