Left Ventricular Dilatation Increases the Risk of Ventricular Arrhythmias in Patients With Reduced Systolic Function.

Abstract

BACKGROUND:

Reduced left ventricular (LV) ejection fraction increases the risk of ventricular arrhythmias; however, LV ejection fraction has a low sensitivity to predict ventricular arrhythmias. LV dilatation and mass may be useful to further risk-stratify for ventricular arrhythmias.

METHODS AND RESULTS:

Patients from the Genetic Risk of Assessment of Defibrillator Events (GRADE) study (N=930), a study of heart failure subjects with defibrillators, were assessed for appropriate implantable cardioverter-defibrillator shock and death, heart transplant, or ventricular assist device placement by LV diameter and mass. LV mass was divided into normal, mild, moderate, and severe classifications. Severe LV end-diastolic diameter had worse shock-free survival than normal and mild LV end-diastolic diameter (P=0.0002 and 0.0063, respectively; 2-year shock free, severe 74%, moderate 80%, mild 91%, normal 88%; 4-year shock free, severe 62%, moderate 69%, mild 72%, normal 81%) and freedom from death, transplant, or ventricular assist device compared with normal and moderate LV end-diastolic diameter (P<0.0001 and 0.0441, respectively; 2-year survival: severe 78%, moderate 85%, mild 82%, normal 89%; 4-year survival: severe 55%, moderate 64%, mild 63%, normal 74%). Severe LV mass had worse shock-free survival than normal and mild LV mass (P=0.0370 and 0.0280, respectively; 2-year shock free: severe 80%, moderate 81%, mild 91%, normal 87%; 4-year shock free: severe 68%, moderate 73%, mild 76%, normal 76%) but no association with death, transplant, or ventricular assist device (P=0.1319). In a multivariable Cox proportional hazards analysis adjusted for LV ejection fraction, LV end-diastolic diameter was associated with appropriate implantable cardioverter-defibrillator shocks (hazard ratio 1.22, P=0.020). LV end-diastolic diameter was associated with time to death, transplant, or ventricular assist device (hazard ratio 1.29, P=0.0009).

CONCLUSIONS:

LV dilatation may complement ejection fraction to predict ventricular arrhythmias.

CLINICAL TRIAL REGISTRATION:

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02045043.

• Authors: Ryan G Aleong, Matthew J Mulvahill, Indrani Halder, Nichole E Carlson, Madhurmeet Singh, Heather L Bloom, Samuel C Dudley, Patrick T Ellinor, Alaa Shalaby, Raul Weiss, Rebecca Gutmann, William H Sauer, Kumar Narayanan, Sumeet S Chugh, Samir Saba, Barry London
• Journal: Journal of the American Heart Association (J Am Heart Assoc) Vol. 4 Issue 8 Pg. e001566 (Jul 31 2015) ISSN: 2047-9980 [Electronic] England
• PMID: 26231842 (Publication Type: Journal Article, Multicenter Study, Observational Study, Research Support, N.I.H., Extramural)
• Copyright: © 2015 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Topics

• Aged
• Arrhythmias, Cardiac (diagnosis, etiology, mortality, physiopathology, therapy)
• Chi-Square Distribution
• Death, Sudden, Cardiac (etiology, prevention & control)
• Defibrillators, Implantable
• Dilatation, Pathologic
• Disease-Free Survival
• Electric Countershock (instrumentation)
• Female
• Heart Failure (etiology, physiopathology, therapy)
• Heart Transplantation
• Heart-Assist Devices
• Humans
• Hypertrophy, Left Ventricular (complications, diagnosis, mortality, physiopathology, therapy)
• Kaplan-Meier Estimate
• Male
• Middle Aged
• Multivariate Analysis
• Proportional Hazards Models
• Prospective Studies
• Risk Assessment
• Risk Factors
• Systole
• Time Factors
• Treatment Outcome
• United States
• Ventricular Dysfunction, Left (complications, diagnosis, mortality, physiopathology, therapy)
• Ventricular Function, Left