Ambulatory Post-Syncope Arrhythmia Protection Feasibility Study

OBJECTIVES To conduct a prospective observational study assessing a unique outpatient care
model in which syncope patients are provided with, and trained to use, a wearable
defibrillator prior to discharge from the emergency department (ED). Observational data will
be collected to assess the logistics of equipping patients with the device and providing
training in the ED, and the ability of patients to receive follow-up care on an outpatient
basis. In addition, data will be collected to confirm that the device meets expected safety.
The experience gained from this stage of the study will be used to guide future studies of
device's functionality enhancements and definitive device safety and efficacy.

STUDY POPULATION Participants will be patients presenting to the ED following a syncope event
which has been defined as cardiac, or potentially cardiac, i.e. undiagnosed in nature.

INTERVENTION A wearable defibrillator optimized for short-term ambulatory use with adhesive
electrodes will be prescribed for up to 14 days of use following emergency department
discharge or until the physician responsible for the subject's care defines an alternative
treatment plan.

STUDY DESIGN This is a single-arm feasibility study.

STUDY SIZE The study will enroll a minimum of 50 and a maximum of 80 subjects. A maximum of
20 centers will be used for enrollment.

Inclusion Criteria:

1. Age≥18

2. Experienced a syncopal event within the past 48 hours

3. Either one of the following profiles(A or B) apply:

A. ED workup indicates that the patient may have experienced syncope that is cardiac in
nature (any one or more of the following apply:

- History or diagnosis of structural heart disease

- History of cardiovascular disease

- Age ≥ 40

- Palpitations experienced pre-syncope

- Major ECG abnormalities:

- QRS-duration greater than 140 ms

- PR-interval greater than 200 ms

- Non-specific repolarization abnormality

- Syncope experienced without any warning

- Syncope experienced while supine

- Syncope during exercise B. ED workup does not indicate a clear cause of the syncopal
event

Exclusion Criteria:

1. Clear diagnosis of non-cardiac syncope (e.g. orthostatic hypotensive syncope,
vasovagal syncope, carotid sinus syncope, situational fainting)

2. An active implantable cardioverter-defibrillator (ICD)

3. An active unipolar pacemaker

4. Significant risk or suffering a cardiovascular event such as:

- Symptoms of New York Heart Association (NYHA) class III or IV heart failure

- ED diagnosis of acute coronary syndrome

- Having required resuscitation in response to the index syncopal event

- Advanced directive prohibiting resuscitation (DNR)

6. Physical or mental conditions preventing subjects from interacting with or wearing the
device as determined by the investigating physician.

7. Bandages or other clinical condition preventing SWD 1000 use 8. Injuries or other
conditions beyond simple syncope that require hospitalization 9. Travel out of town during
the study participation period that prevents the field service representative from visiting
the subject daily 10. Unable or unwilling to provide written informed consent