Assessment of Combined CCM and ICD Device in HFrEF

Inclusion Criteria: Individuals must meet all the following: 1. Patient is aged 18 years or older; 2. Patient meets the Stage C or D criteria of the Universal Definition of Heart Failure ; 3. Patient has HFrEF (LVEF ≤40%); 4. Patient is on GDMT for heart failure; 5. Patient has a Class I or Class II indication for an ICD 6. Patient has a reasonable expectation of meaningful survival of \> 1 year; 7. Patient has either non-ischemic cardiomyopathy or ischemic cardiomyopathy and is at least 40 days post-MI, if an MI occurred; 8. Patient is willing to give informed consent, available for scheduled study follow-up visits, and able to complete all testing described in the study protocol at the investigational site location. Exclusion Criteria: An individual who meets any of the following criteria will be excluded from participation in this study: 1. Patients should not have severe AI or AS, and should not have MS; additionally, patients undergoing DE testing should not have severe MR; 2. Patients who have undergone mitral valve repair or clip within 90 days prior to study consent; 3. Cardiac surgery within 90 days or a PCI procedure within 30 days prior to study consent; 4. Prior heart transplant or ventricular assist device; 5. Implanted mechanical tricuspid valve; 6. PR interval greater than 375ms or advanced AV block; 7. In situ S-ICD, pacemaker, or CRT device; 8. Indicated for CRT; 9. End stage renal disease, currently on dialysis, or with other major medical disorder (e.g. liver failure, terminal cancer); 10. Indicated for permanent bradyarrhythmia pacing; 11. Unstable angina pectoris within 30 days prior to study consent; 12. Pregnant or planning to become pregnant during the study; 13. Participating in another cardiac investigational device or drug study at the same time (or within 30 days prior to study consent); Note: Registries and other observational studies are acceptable. 14. Other criteria that preclude Optimizer INTEGRA CCM-D implantation and/or CCM therapy, as determined by Investigator.