Heart Failure Optimization Study

This study will be conducted at thirty to sixty sites, initially in US and Europe. It will be
used to observe the rate of recovery of ventricular function (EF>35%) between 90 and 180 days
in newly diagnosed HF patients who were prescribed the WCD ≤ 10 days post-discharge after
hospitalization for a primary reason of new onset HF (≤30 days since first HF
hospitalization), with ischemic or non-ischemic cardiomyopathy, and have already used a WCD
for 90 ± 14 days. For the first 90 days of WCD use, patients will be enrolled in a pre-study
registry. The FDA-approved WCD will be prescribed for up to 6 months of use after hospital
discharge, with the option for longer use under physician discretion. Approximately 870
subjects will enroll into the pre-study registry and 750 subjects into the study.

Inclusion Criteria:

Part 1

- Patients (≥18 years old) who were prescribed the WCD ≤ 10 days post-discharge after
hospitalization for a primary reason of new onset HF (≤30 days since first HF
hospitalization), with ischemic or nonischemic cardiomyopathy, and have used the WCD
for no more than 30 days.

- Patients who had an EF ≤ 35% during index hospitalization (must be last measurement if
performed multiple times).

Part 2

- Patients (≥18 years old) who were prescribed the WCD ≤ 10 days post-discharge after
hospitalization for a primary reason of new onset HF (≤30 days since first HF
hospitalization), with ischemic or nonischemic cardiomyopathy, and have already used a
WCD for 90 ± 14 days.

- Patients who had an EF ≤ 35% during index hospitalization (must be last measurement if
performed multiple times). Of note, EF at 90 ± 14 days post-hospitalization does not
need to be low to be included in the study.

Exclusion Criteria:

- Patients under 18 years old.

- Patients who have an active unipolar pacemaker.

- Patients with a physical or mental condition that could impair their ability to
properly interact with the device.

- Patients currently participating in another clinical study.

- Patients with any skin condition that would prevent wearing the device.

- Patients with an advanced directive prohibiting resuscitation.

- Patients who are indicated for cardiac resynchronization therapy or have a QRS
duration of ≥135 ms.

- Patients with recent myocardial infarction or coronary revascularization (since start
of WCD wear; i.e. 0-90 days of WCD wear).