Author + information
- Rahul G. Muthalaly, MD, MPHa,b,
- Raymond Y. Kwong, MD, MPHa,b,
- Roy M. John, MBBS, PhDa,b,
- Rob J. van der Geest, PhDc,
- Qian Tao, PhDc,
- Benjamin Schaeffer, MDa,b,
- Shinichi Tanigawa, MDa,b,
- Tomofumi Nakamura, MD, PhDa,b,
- Kyoichi Kaneko, MD, PhDa,b,
- Usha B. Tedrow, MD, MSa,b,
- William G. Stevenson, MDa,b,
- Laurence M. Epstein, MDa,b,
- Sunil Kapur, MDa,b,
- Paul C. Zei, MD, PhDa,b and
- Bruce A. Koplan, MD, MPHa,b,∗ ()
- aCardiovascular Division, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts
- bHarvard Medical School, Boston, Massachusetts
- cLeiden University Medical Center, Leiden, the Netherlands
- ↵∗Address for correspondence:
Dr. Bruce A. Koplan, Arrhythmia Service, Brigham and Women’s Hospital, 75 Francis Street, Boston Massachusetts 02115.
Objectives The aim of this study was to assess the utility of left ventricular (LV) entropy, a novel measure of myocardial heterogeneity, for predicting cardiovascular events in patients with dilated cardiomyopathy (DCM).
Background Current risk stratification for ventricular arrhythmia in patients with DCM is imprecise. LV entropy is a measure of myocardial heterogeneity derived from cardiac magnetic resonance imaging that assesses the probability distribution of pixel signal intensities in the LV myocardium.
Methods A registry-based cohort of primary prevention implantable cardioverter-defibrillator patients with DCM had their LV entropy, late gadolinium enhancement (LGE) presence, and LGE mass measured on cardiac magnetic resonance imaging. Patients were followed from implantable cardioverter-defibrillator placement for arrhythmic events (appropriate implantable cardioverter-defibrillator therapy, ventricular arrhythmia, or sudden cardiac death), end-stage heart failure events (cardiac death, transplantation, or ventricular assist device placement), and all-cause mortality.
Results One hundred thirty patients (mean age 55 years, 83% men, LV ejection fraction 29%, mean LV entropy 5.58 ± 0.72, LGE present in 57%) were followed for a median of 3.2 years. Eighteen (14.0%) experienced arrhythmic events, 17 (13.1%) experienced end-stage heart failure events, and 7 (5.4%) died. LV entropy provided substantial improvement of predictive ability when added to a model containing clinical variables and LGE mass (hazard ratio: 3.5; 95% confidence interval: 1.42 to 8.82; p = 0.007; net reclassification index = 0.345, p = 0.04). For end-stage heart failure events, LV entropy did not improve the model containing clinical variables and LGE mass (hazard ratio: 2.03; 95% confidence interval: 0.78 to 5.28; p = 0.14). Automated LV entropy measurement has excellent intraobserver (mean difference 0.04) and interobserver (mean difference 0.03) agreement.
Conclusions Automated LV entropy measurement is a novel marker for risk stratification toward ventricular arrhythmia in patients with DCM.
- implantable cardioverter-defibrillator
- magnetic resonance imaging (MRI)
- sudden cardiac death
Dr. Muthalaly is supported by a Doctors-in-Training scholarship from Avant Mutual and an overseas research grant from Monash Health. Dr. John has received lecture honoraria from Abbott; and research support from Biosense Webster and Abbott. Dr. Stevenson is a coholder of a patent for needle ablation consigned to Brigham and Women’s Hospital. Dr. Epstein has received consulting fees from Boston Scientific, Medtronic, and Spectranetics. Dr. Tedrow has received consulting fees from St. Jude Medical; and research support from Boston Scientific and Biosense Webster. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose. Drs. Muthalaly and Kwong contributed equally to this work as first authors.
- Received April 24, 2018.
- Revision received June 4, 2018.
- Accepted July 3, 2018.
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