Synchronized Diaphragmatic Stimulation in Symptomatic Heart Failure

Inclusion Criteria:

* NYHA classes II/III on optimal Guideline Directed Medical Therapy (GDMT)
* QRS duration ≤ 130 ms
* EF≤ 40%

Exclusion Criteria:

* Baseline 6 minute walk test \> 500 meters or \< 200 meters
* NT-proBNP\< 250 if on loop diuretics, or NT-proBNP \< 500 if not on loop diuretics
* Supine resting heart rate \> 140 bpm
* Systolic blood pressure \< 80 mmHg or \> 170 mmHg
* Serum creatinine \> 2.5 mg/dL
* Serum hepatic function 3x ULN
* Any of the following within the previous 3 months: unstable angina, AMI, CABG, PTCA, CVA/TIA, persistent AF (\> 24 hours), symptomatic NSVT or DCCV
* Any inotropic drug treatment within the previous 3 months
* Bradycardia (heart rate \< 50 beats/min), atrial arrhythmias with rates \> 100 beats/min, sustained ventricular tachycardia or frequent ventricular ectopy \>10% present during screening
* Significant uncontrolled symptomatic bradyarrhythmia, atrial fibrillation, unstable ventricular arrhythmias or frequent ventricular ectopy \> 10% documented within the previous 3 months
* Reversible non-ischemic cardiomyopathy
* Valvular disease requiring intervention within the next 12 months or presence of significant valve disease as determined by the site cardiologist as:

  1. Greater than mild mitral valve stenosis
  2. Greater than moderate mitral valve regurgitation
  3. Greater than mild tricuspid valve stenosis
  4. Greater than moderate-severe tricuspid valve regurgitation
  5. Greater than moderate aortic stenosis
  6. Greater than moderate aortic regurgitation
  7. Greater than mild-moderate pulmonic stenosis
  8. Greater than moderate pulmonic regurgitation
* Severe primary pulmonary disease, including pulmonary arterial hypertension. PAP sys \>70 mmHg at rest
* Severe COPD, other respiratory or lung diseases where FEV \< 50%
* Presence of more than small pleural effusion or history of pleural drainage within the previous 6 months
* Known history of diaphragmatic paralysis or suspicion confirmed by unilateral or bilateral elevation of the diaphragm on chest x-ray
* Pericardial disease
* Diabetic neuropathy
* Existing diaphragmatic stimulation for respiration assist
* Present LVAD, Baroreflex Activation Therapy, Cardiac Contractility Modulation or interatrial shunt devices; temporary mechanical cardiac assist devices (current or within the previous 3 months); or CRT that is indicated or implanted and functional
* Contraindications to laparoscopic access to the diaphragm, as determined by the implanting physician
* Known intra-abdominal pathology which could increase the risk of laparoscopic access to the diaphragm.
* Previous open laparotomy within 1 year
* Previous thoracic or abdominal organ transplant
* Drug induced immuno-suppression
* Body mass index \> 40
* Enrollment in a concurrent investigation / clinical study
* Having a life expectancy of \<1 year due to any condition
* Pregnant or planning a pregnancy during the study period
* Known allergies to implantable device materials
* History of systemic infection requiring the use of intravenous antibiotics within the previous 3 months