The purpose of this Post-Approval Study (PAS) is to evaluate the long-term performance of the Model 4798 Left Ventricular (LV) lead in a real-world patient population. Patients will be followed for the duration of the PAS. This study is required by FDA as a condition of approval of the Model 4798 LV lead and is integrated within the Product Surveillance Registry (PSR).

The Attain Stability Quad (ASQ) PAS is a multi-center, single arm, prospective observational study. However, in the US, retrospective enrollments from participants in the IDE study (IDE #G170020) are allowed.

Inclusion Criteria:

• Patient or legally authorized representative provides written authorization and/or consent per institution and geographical requirements
• Patient has or is intended to receive or be treated with a Model 4798 lead and a Medtronic CRT device
• Patient within 30 days of therapy received at the time of their initial PSR platform enrollment

Exclusion Criteria:

• Patient who is, or is expected to be inaccessible for follow-up
• Patient with exclusion criteria required by local law
• Patient is currently enrolled in or plans to enroll in any concurrent drug and/or device study that may confound results

The study population includes patients that are or will be implanted with a Model 4798 lead and a Medtronic CRT device.