Acute Subcutaneous Defibrillation Study

Protocol page 9, 10; Study Backgroud

Implantation of a defibrillation system that does not require entry into the
subject*s venous system offers several advantages over transvenous systems.
Such a system may be easier to implant because it removes the necessity to
enter the venous system and heart chamber. It also may eliminate the need for
fluoroscopic guidance because the implant procedure can potentially be based on
anatomical landmarks. Given that leads are not implanted in the vasculature,
such a system may also be more easily manageable in the event lead
complications arise in the subject. Without a defibrillation electrode within
the heart, a portion of energy delivered to the subject will not pass through
the heart.
Energy required for successful defibrillation is expected to be higher for a
subcutaneous defibrillator compared to current transvenous systems. In fact, the
Cameron Health S-ICD is currently approved in several countries and delivers up
to 80J. Thus, Medtronic is proposing to study defibrillation efficacy from
induced VF episodes of up to 20 seconds in duration at energies up to 65J to
ensure adequate defibrillation efficacy at a maximum device output of up to 80J.
Medtronic is exploring a non-transvenous defibrillation system intended to
improve upon the commercially available system manufactured by Cameron Health
Inc. by offering a more optimal shock waveform that could achieve required
defibrillation efficacy with less energy and smaller device size. The proposed
study is required to determine and test the defibrillation efficacy prior to
development of this implantable subcutaneous defibrillation system.
To maintain the advantage of performing implants without accessing the venous
space, a subcutaneous device-based method for inducing VF during implant
testing is preferred. Medtronic is exploring a non-transvenous method of VF
induction intended to improve upon the commercially available system.

The primary purpose is to assess the defibrillation efficacy of Medtronic
subcutaneous defibrillation system.

This is a prospective, multi site, non-randomized, pre-market acute feasibility
study.
Data is collected at baseline, implantation, the routine post-ICD implantation
visit (between 30 and 80 days).
An analysis is performed after 20 subjects completed the defibrillation testing
according to the protocol. It is then decided whether the study will continue
according to the protocol or that the protocol will be changed. The decision is
taken by the Medtronic study team based on interim analysis.

In the Netherlands only patients who will receive a S-ICD will be enrolled in
the study.

The extra interventions for the subjects in the Netherlands are;
- An transvenous catheter (or RV lead) and an additional incision for temporary
lead placement (for protocol version 1 and potentially for protocol version 2).

- In order to test the defibrillation efficacy of the test system, a maximum of
3 VF inductions wil be done and terminated with the test system.

- There are two fluoroscopy images taken when the test system is implanted.

See protocol page 35-40
Risks associated with the implantation of a (subcutaneous) ICD, the extended
procudure time, additional incisions and the additional VF inductions and
defibrillation.