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Updated: May 24, 2026
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A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation
Published on: February 28, 2012
Clinical comparison of ICD detection algorithms that include rapid-VT zones.
David S Hirsh1, Larry A Chinitz, Neil E Bernstein
1Leon H. Charney Heart Rhythm Center, New York University School of Medicine, New York, New York, USA.
Pacing and Clinical Electrophysiology : PACE
|March 6, 2012
Summary
The Boston Scientific implantable cardioverter defibrillator (ICD) algorithm shows a longer time to detect ventricular fibrillation (VF), delaying device charging. This may impact the safety of antitachycardia pacing (ATP) for treating rapid ventricular tachycardia (VT).
Area of Science:
- Cardiology
- Biomedical Engineering
Background:
- Antitachycardia pacing (ATP) for ventricular tachycardia (VT) relies on implantable cardioverter defibrillators (ICDs) distinguishing VT from ventricular fibrillation (VF).
- Accurate and rapid VT/VF discrimination is crucial for timely and appropriate device therapy.
Purpose of the Study:
- To compare the time to device charging following VF induction across different ICD multizone detection algorithms.
- To evaluate the performance of VT/VF discrimination algorithms from Boston Scientific, Medtronic, and St. Jude Medical devices.
Main Methods:
- A prospective cohort study of 62 patients undergoing ICD implantation.
- Induction of VF at the time of implantation to test device algorithms.
- Analysis of time to device charging and therapy initiation for Boston Scientific, Medtronic, and St. Jude Medical devices.
Main Results:
- Mean time to charging was significantly prolonged for the Boston Scientific group (4.24 seconds) compared to Medtronic (3.99 seconds) and St. Jude Medical (3.00 seconds).
- A higher percentage of tests showed charge initiation >5 seconds from VF induction in the Boston Scientific group (19%) versus Medtronic (4%) and St. Jude Medical (0%).
- Antitachycardia pacing (ATP) was initiated first in 9.4% of tests with the Boston Scientific device.
Conclusions:
- The Boston Scientific multizone VT/VF discrimination algorithm leads to a prolonged time for VF detection and subsequent device charging.
- Further research is necessary to determine the clinical significance of these prolonged detection times.
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