The purpose of this study is to evaluate long-term performance of the DF4 Connector System. This evaluation is based on the number of DF4 lead-related complications occurring during the study compared to the number of leads enrolled in the study. The DF4 systems will be followed for 5 years after implant. This study is required by FDA as a condition of approval of the DF4 Connector Systems. This study is conducted within Medtronic's post-market surveillance platform.

Inclusion Criteria:

• Subject or legally authorized representative provides written authorization and/or consent per institution and geographical requirements
• Subject is intended to be implanted or is within 30 days post-implant of a DF4 Connector System with a Medtronic DF4 lead used for a pacing, sensing and/or defibrillation application

Exclusion Criteria:

• Subject who is, or will be inaccessible for follow-up at a study site
• Subject with exclusion criteria required by local law (Europe, Central Asia [ECA] only)
• Implant and follow-up data, including any adverse device effects and system modifications at implant through the time of enrollment are unavailable

Patients intended to be implanted or are within 30 days post-implant of a DF4 Connector System with a Medtronic DF4 lead. All subjects must meet Inclusion criteria and none of the Exclusion criteria.