Respicardia, Inc. Pivotal Trial of the remedē System

Inclusion Criteria:

1. At least 18 years of age

2. Central Sleep apnea confirmed by core lab analysis of PSG with EEG within 40 days of
scheduled implant:

- Apnea/Hypopnea Index (AHI) greater than or equal to 20;

- Central Apnea Index (CAI) at least 50% of all apneas, with at least 30 central
apnea events;

- Oxygen Desaturation Index (OAI) less than or equal to 20% of the total AHI

3. Medically stable for 30 days prior to all baseline testing (including PSG), i.e., no
hospitalizations for illness, no breathing mask-based therapy, and on stable
medications and therapies:

- Stable medications are defined as no changes during this period except for those
within a pre-specified sliding scale medication regimen;

- If the subject has heart failure, the baseline testing (including PSG) should
occur at least 6 months after initial diagnosis;

- If the subject has systolic heart failure, the baseline testing (including PSG)
should occur after maximally titrating beta blockers, angiotensin converting
enzyme inhibitors (ACE-I) and other medications indicated in the current
guidelines (unless contraindicated or not considered medically necessary) and
after receiving any indicated device therapy including devices for cardiac
resynchronization therapy and/or primary prevention of sudden cardiac death;

- If subject has a hospitalization or physician visit requiring IV medication
between the screening PSG and implant, the subject must be re-screened when
stable

4. Expected to tolerate study procedures in the opinion of the investigator, in
particular:

- Ability to lie down long enough to insert the remede system without shortness of
breath and able to tolerate instrumentation for the Polysomnogram/Polygram
testing;

- Expected to tolerate therapy titration and the sensation of therapy, and
communicate therapy experience.

5. In the investigator's opinion, willing and able to comply with all study requirements

6. Signed the Institutional Review Board/Medical Ethics Committee approved informed
consent (HIPAA authorization in the U.S.)

Exclusion Criteria:

1. Pacemaker dependent subjects without any physiologic escape rhythm

2. Suspected inability to place catheter for delivery of stimulation lead (e.g.
previously know coagulopathy, distorted anatomy, prior failed pectoral implant, etc.)

3. Evidence of phrenic nerve palsy

4. More than 2 previous open chest surgical procedures (e.g., CABG)

5. Etiology of central sleep apnea known to be caused primarily by pain medication

6. Documented history of psychosis or severe bipolar disorder

7. Cerebrovascular accident (CVA) within 12 months of baseline testing

8. History of idiopathic pulmonary hypertension, World Health Organization Class 1

9. Limited pulmonary function with either forced expiratory volume (FEV) 1/forced vital
capacity (FVC) less than 65% of predicted value or FVC less than 60% of predicted
value

10. Baseline oxygen saturation less than 92% while awake and on room air after 5 minutes
of quiet rest

11. Anticipated need for chronic oxygen therapy or breathing mask-based therapy for 6
months post therapy initiation visit

12. Active infection or sepsis within 30 days of enrollment

13. Currently on renal dialysis or creatinine level greater than 2.5 mg/dL or calculated
creatinine clearance equal to or less than 30 ml/min using the Cockcroft-Gault
equation

14. Poor liver function with baseline aspartate transaminase (AST), alanine transaminase
(ALT), and/or total bilirubin greater than 3 times the upper limit of normal (per lab
normals at each site)

15. Hemoglobin less than 8 gm/dL

16. In subjects with heart failure, American College of Cardiology (ACC)/American Heart
Association Heart (AHA) Stage D

17. Within the 3 months prior to baseline testing, any of the following: uncorrected
severe valvular stenosis, valve replacement or repair (percutaneous or surgical),
myocardial infarction (MI), coronary artery bypass grafting (CABG) surgery,
percutaneous coronary intervention (PCI), cardiac ablation, new cardiac
resynchronization device or new pacemaker implant

18. New implantable cardioverter defibrillator or any implantable device generator
change-out within 30 days prior to baseline testing or anticipated within the first 6
months of enrollment

19. Other anticipated surgery or invasive procedure expected to affect ability to perform
testing at 6-month post-therapy initiation visit

20. Unstable angina

21. Allergy to or intolerant of contrast dye

22. Pregnancy or of child bearing potential without a negative pregnancy test within 10
days prior to remede system implant

23. Life expectancy or expected time to transplant or left ventricular assist device of
less than 12 months

24. Currently enrolled or planning to enroll in another study that may conflict with
protocol requirements or confound subject results in this trial