Tachycardia electrograms for testing S-ICD discrimination algorithm

  • Research type

    Research Study

  • Full title

    The collection of supraventricular and ventricular tachycardia surface electrograms during electrophysiology studies for testing a novel Subcutaneous Implantable Cardioverter-Defibrillator (S-ICD) discrimination algorithm.

  • IRAS ID

    138620

  • Contact name

    John Morgan

  • Contact email

    jmm@hrclinic.org

  • Sponsor organisation

    University Hospital Southampton NHS Foundation Trust

  • Research summary

    The purpose of this study is to collect a series of heart rhythm recordings in order to test a component of a new Subcutaneous Implantable Cardioverter-Defibrillator (S-ICD).

    S-ICDs have been developed to improve on the traditional implantable cardioverter defibrillators (ICD). S-ICD and ICDs are implanted in people thought to be at high risk dying from lethal fast heart rhythm disturbances (tachy-arrhythmias). The ICD works by sensing, detecting and treating lethal tachy-arrhythmias.

    Unfortunately S-ICDs deliver more inappropriate shocks for non lethal arrhythmias compared to ICDs. This is due to something called T wave oversensing (TWOS). This occurs when a single heart beat is double counted by the S-ICD thus doubling the heart rate and resulting in shock delivery, inappropriately. This can cause significant discomfort and psychological distress to patients.

    In order to help develop S-ICD sensing technology, we propose the following study.

    To record 40 non-lethal and 20 potentially lethal tachy-arrhythmias from different patients and then test how accurately a new algorithm (computer programme) can discriminate lethal from non lethal arrhythmias. The arrhythmias will be recorded in the cardiac electrophysiology (EP) laboratory. We will recruit patients who are already undergoing EP studies for the investigation and treatment of tachy-arrhythmias. During an EP study it is normal that a tachycardia is induced. During the tachycardia a system called PRIME ECG (which is CE marked) will record the arrhythmia.

    Once sufficient recordings have been made, we will send the anonymised data to a company called Medtronic Inc. in the USA. Medtronic are market leaders in ICD technology and are developing a new S-ICD. Medtronic have developed an algorithm and will use the data we have provided them to test and refine this algorithm. This algorithm will be part of their new S-ICD. Neither their algorithm nor their S-ICD is currently CE marked.

  • REC name

    London - Brent Research Ethics Committee

  • REC reference

    13/LO/1800

  • Date of REC Opinion

    12 Nov 2013

  • REC opinion

    Favourable Opinion