The purpose of the study is:

• To evaluate the Heart Failure Risk Status (HFRS) feature performance.
• To establish the feasibility of remote follow-up in which patient risk triaging is performed by nurse-led review of HFRS feature as supplemental information.

Inclusion Criteria:

Patients that meet all of following criteria could be included in the study:

• Implant of a commercially available Medtronic CRTD or ICD device with or without the Optivol Fluid Status Monitoring feature.
• Inclusion in the Medtronic Carelink Network.
• Local consent available for CL network as well as general local consent available for the use of data in observational studies signed and informative sheet delivered.

Exclusion Criteria:

• Patients under the age of 18 years.

Study population will include patients of both sexes included in the Medtronic CareLink® Network and implanted with a Medtronic wireless implantable cardiac defibrillator (ICD) or cardiac resynchronization therapy device with defibrillation capabilities device (CRT-D) at Hospital Araba (former Hospital Txagorritxu). There are approximately 223 ICD and CRT-D patients included in the CareLink® Network at this site, and average number of transmissions per month is ~80, so it is expected that 480 transmissions are received during the study duration.

From this population, less than 10% are implanted with a device without Optivol® feature. For these patients we will not have HFRS data.