The LINQ™ Respiration study will collect and characterize Reveal LINQ™ derived respiration data from patients undergoing a simulated 24-hour time period while being monitored with capnography.

The Reveal LINQ™ Respiration study is a Non-Significant Risk IDE, observational, non-randomized, multi-center, clinical study. The study is expected to be conducted at up to 5 centers in the United States and up to 100 subjects will be enrolled, with no more than 25 subjects enrolled per site. In addition, a minimum of 30% of all enrolled subjects will have a history of heart failure.

All enrolled subjects will either have the investigational LINQ HF or ALLEVIATE-HF RAMware downloaded onto their implanted Reveal LINQ device, Holter monitor and capnography monitor applied and undergo a series of activity and breathing maneuvers. The expected duration of subject participation in the study (from start of study procedures to study exit) is approximately 1.5 hours. The expected total study duration (from time of first enrollment to the exit of last enrolled subject) is approximately 3 months.

All Adverse events will be collected throughout the study duration of a subject's participation in the study, beginning at the time of informed consent.

Inclusion Criteria:

• Patient is ≥ 55 years old
• Patient (or patient's legally authorized representative) is willing and able to provide written informed consent
• Patient is willing and able to comply with the study procedures
• Patient has an active Medtronic Reveal LINQ device that has been implanted for ≥ 60 days and no more than 3 years

Exclusion Criteria:

• Patient has an existing condition that necessitates the use of supplemental oxygen
• Patient has an active acute respiratory infection or a respiratory disorder that may affect ability to perform respiratory maneuvers
• Patient has NYHA Class IV heart failure per most recent assessment
• Any concomitant condition that might endanger the patient through participation in the study or interfere with study procedures, as assessed by the investigator
• Patient is enrolled in another study that could confound the results of this study
• Patient has an existing implantation of Medtronic IPG, ICD, CRT-D or CRT-P device

The target population for the LINQ Respiration study will include subjects who are ≥ 55 years old and implanted with a Reveal LINQ device for ≥60 days and no longer than 3 years. In addition, a minimum of 30% of all enrolled subjects will have a documented history of heart failure.

No plan to share IPD