Clustered Ventricular Arrhythmias in ICD Patients

Mar 17, 2020
Font Size
A
A
A
Authors:
Elsokkari I, Parkash R, Tang A, et al.
Citation:
Mortality Risk Increases With Clustered Ventricular Arrhythmias in Patients With Implantable Cardioverter-Defibrillators. JACC Clin Electrophysiol 2020;Mar 6:[Epub ahead of print].
Summary By:
Fred Morady, MD, FACC

Study Questions:

What is the prognostic significance of clustered episodes of ventricular tachycardia/ventricular fibrillation (VT/VF) that do not meet the criteria for an electrical storm (ES) in patients with an implantable cardioverter-defibrillator (ICD)?

Methods:

The data for this study were gathered from the Resynchronization in Ambulatory Heart Failure Trial, which had a sample size of 1,764 patients with an ICD. Clustered ventricular arrhythmias (CVAs) were defined as ≥2 episodes of VT/VF (VAs) within 3 months. Patients with an ES (≥3 VAs within 24 hours) were excluded. The mortality rates of patients with and without CVAs were compared.

Results:

CVAs occurred in 465 patients and unclustered VAs occurred in 406 patients. During a median follow-up of 40.1 months, unclustered VAs were associated with a 1.45-fold higher risk of mortality compared to the mortality rate in patients with no VAs, and patients with CVAs had a 2.68-fold higher risk of mortality. Mortality risk was directly related to the number of VAs within the cluster. The incremental risk of mortality in patients with CVAs was greater when there were VAs that required termination with an ICD shock than when antitachycardia pacing alone was sufficient.

Conclusions:

Among patients with an ICD, CVAs are predictive of higher mortality than when VAs occur at a frequency of <2 episodes within 3-month intervals.

Perspective:

It already is well established that ES have a negative impact on survival. This study, for the first time, presents data on the incremental mortality risk of VA burden among ICD patients who have CVAs that do not meet the criteria of ES. Still unknown is whether the incremental risk of mortality associated with CVAs can be attenuated by prevention of the VAs.

Clinical Topics: Arrhythmias and Clinical EP, Heart Failure and Cardiomyopathies, Prevention, Implantable Devices, SCD/Ventricular Arrhythmias, Atrial Fibrillation/Supraventricular Arrhythmias, Acute Heart Failure

Keywords: Arrhythmias, Cardiac, Defibrillators, Implantable, Heart Failure, Risk, Secondary Prevention, Stroke, Tachycardia, Ventricular, Ventricular Fibrillation


< Back to Listings