The LEADLESS Pacemaker IDE Study (Leadless II)

The purpose of this study is to evaluate the safety and effectiveness of the leadless
pacemaker system in treating patients with a slow heart rate or irregular heartbeats. The
Nanostim leadless pacemaker provides bradycardia pacing as a pulse generator with built-in
battery and electrodes, for permanent implantation in the right ventricle. As a leadless
pacemaker, it does not need a connector, pacing lead, or pulse generator pocket, but it has
the same operating principles as a conventional pacemaker.

Inclusion Criteria:

1. Subject must have one of the clinical indications before device implant in adherence
with Medicare, ACC/AHA/HRS/ESC single chamber pacing guidelines including:

- Chronic and/or permanent atrial fibrillation with 2 or 3° AV or bifascicular
bundle branch block (BBB block), including slow ventricular rates (with or
without medication) associated with atrial fibrillation; or

- Normal sinus rhythm with 2 or 3° AV or BBB block and a low level of physical
activity or short expected lifespan (but at least one year); or

- Sinus bradycardia with infrequent pauses or unexplained syncope with EP findings;
and

2. Subject ≥18 years of age; and

3. Subject has life expectancy of at least one year; and

4. Subject is not enrolled in another clinical investigation; and

5. Subject is willing to comply with clinical investigation procedures and agrees to
return for all required follow-up visits, tests, and exams; and

6. Subject has been informed of the nature of the study, agrees to its provisions and has
provided written informed consent, approved by the IRB; and

7. Subject is not pregnant and does not plan to get pregnant during the course of the
study.

Exclusion Criteria:

1. Subject has pacemaker syndrome, has retrograde VA conduction or suffers a drop in
arterial blood pressure with the onset of ventricular pacing; or

2. Subject is allergic or hypersensitive to <1 mg of dexamethasone sodium phosphate; or

3. Subject has a mechanical tricuspid valve prosthesis; or

4. Subject has a pre-existing endocardial pacing or defibrillation leads; or

5. Subject has current implantation of either conventional or subcutaneous implantable
cardioverter defibrillator (ICD) or cardiac resynchronization therapy (CRT); or

6. Subject has an implanted vena cava filter; or

7. Subject has evidence of thrombosis in one of the veins used for access during the
procedure; or

8. Subject has an implanted leadless cardiac pacemaker; or

9. Subject had recent cardiovascular or peripheral vascular surgery within 30 days of
enrollment