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A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation
16:40

A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation

Published on: February 28, 2012

Seasonal variations of ventricular arrhythmia clusters in defibrillator recipients

Thomas Stuber1, Christa Eigenmann, Etienne Delacrétaz

  • 1Swiss Cardiovascular Center Berne, University Hospital, Berne, Switzerland.

Pacing and Clinical Electrophysiology : PACE
|August 23, 2006
PubMed

Insights

Ventricular arrhythmia clusters in implantable cardioverter-defibrillator recipients occur more often in winter and spring. These findings suggest seasonal variations impact electrical storm events, requiring further investigation into contributing factors.

Area of Science:

  • Cardiology
  • Electrophysiology
  • Medical Devices

Background:

  • Clustering ventricular arrhythmias pose management challenges in patients with implantable cardioverter-defibrillators (ICDs).
  • Identifying triggers for these arrhythmias is often difficult.
  • Previous research indicates seasonal patterns in cardiovascular events.

Purpose of the Study:

  • To investigate if seasonal factors influence ventricular electrical instability.
  • To determine if seasonality exacerbates arrhythmia clusters and electrical storm in ICD recipients.

Main Methods:

  • Follow-up of 214 ICD recipients over 3.3 ± 2.2 years.
  • Defined arrhythmia cluster as ≥3 events triggering ICD therapy within 2 weeks.
  • Analyzed time intervals between clusters across months and seasons using statistical tests.

Main Results:

  • 98 arrhythmia clusters were observed in 51 patients over 698 patient-years.
  • Clustering ventricular arrhythmias were significantly more frequent in winter and spring.
  • Time intervals between clusters were shortest in winter (16 days) and spring (11.5 days) compared to summer (34.5 days) and fall (50.5 days).

Conclusions:

  • Significant seasonal variations exist in the incidence of arrhythmia clusters among ICD recipients.
  • The study highlights a link between seasonality and ventricular arrhythmia clustering.
  • Further research is needed to explore environmental, activity-related, or psychological factors driving these seasonal variations.
Abstract

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