The purpose of this study is to compare electrical acute changes between simultaneous and sequential LV pacing and to assess the paced QRSd over a range of inter- and intra-ventricular programmable delays setting during MPP pacing.

The study will be a prospective, single-arm, non-randomized, non-blinded, acute study conducted at CRT device implant and prior to subject discharge. Subjects scheduled to be implanted with a Quadripolar Pacing System who provide informed consent will undergo "Enrollment" and participate in "SCOPE-CRT" study. Enrollment and device implant can occur in the same day. Including Enrollment, each subject's participation is expected to be 1-2 days. The total duration of the study is expected to be 12 months, including Enrollment. Enrollment will include the Informed Consent process, physical examination, and collection of demographics, cardiovascular history, medical history, and medications.

During CRT implant, surface ECG and PV loop recordings will be taken over the different programmable MPP settings. Following data collection, CRT device programming will be left to the discretion of the physician.

Inclusion Criteria:

• Patients with approved indication for CRT by European Society of Cardiology/European Heart Rhythm Association guidelines (ESC/EHRA)
• QRS duration > 130 ms
• Ability to provide informed consent for study participation
• At least 18 years of age

Exclusion Criteria:

• Myocardial infarction within 40 days before enrolment

  • NYHA Class IV
  • Tachyarrhythmia caused by temporary or reversible irritation, e.g. poisoning, electrolyte imbalance, hypoxia, sepsis or acute myocardial infarction
  • Such frequent VT or VF that the therapies would cause an unacceptably rapid depletion of the device batteries
  • VT with few or without clinically relevant symptoms
  • VT or VF treatable by surgery
  • Concomitant diseases that would substantially limit a positive prognosis
  • Accelerated intrinsic rhythm
  • Women who are pregnant

A total of 50 selected heart failure patients with approved indication for CRT by European Society of Cardiology/European Heart Rhythm Association guidelines (ESC/EHRA) will be enrolled for this prospective study.