The ICONIC-M study is a multicenter randomized controlled study to assess patient response to CRT comparing ECGI map guided left ventricular lead placement with empirical lead placement.

The hypothesis of the investigation is to demonstrate that CRT LV lead implantation guided by a map obtained with the Amycard 01C System and showing LV Latest Electrical Activated Site (LEAS) in combination with a CT cardiac venogram improves CRT outcome. An improved CRT outcome is defined as a ≥30% increase in LVESVi reduction compared to empiric CRT LV lead implantation.

The sample size will be 136 in the Control arm and 194 in the Active arm. A total of 330 subjects.

The study follows an adaptive design, in where one interim analysis at 70% enrollment will be performed. The sponsor may stop enrollment when either one of the following conditions apply:

• Statistical significant difference between groups in the primary endpoint has been reached confirming a difference in reduction of the LVESVi of ≥30% in the Active arm compared to the Control arm
• There is no trend or reason to believe statistical significance will be reached with a higher sample size.

Statistical significance (primary endpoint) is reached at interim (70%) or at total (100%) of enrollment with a significance value P lower than 0.025.

The study is conducted at European sites as a Post-Market Clinical Follow-Up study of a CE marked device (Amycard 01C). Its aim is to strengthen clinical evidence by assessing whether the use of this device for CRT planning improves clinical outcome in a statistically significant number of patients.

Inclusion Criteria:

1. Appropriately signed and dated informed consent.
2. Age ≥18 years at time of consent.
3. Received optimal medical therapy for HF for at least 3 months before screening
4. Patient in sinus rhythm at the time of screening fulfilling Class I or IIa criteria per ESC CRT guidelines 2013 .
5. Patient is intended for placement of a CRT device with biventricular (BiV) pacing.

Exclusion Criteria:

1. Previous cardiac pacemaker/CRT/ICD implantation
2. Acute diseases or exacerbations of chronic diseases (as per the investigator's discretion)
3. Contraindications to CT scanning
4. Contraindications to body surface ECG mapping: (ongoing wound healing on the chest (e.g. recent surgery), skin diseases, allergic reactions to surface mapping electrodes and medical band-aid)
5. Pregnant, or subjects planning to become pregnant within 6 months after signing informed consent (a documented negative pregnancy test (serum or blood) is required for women of childbearing potential)
6. Incapacitated individuals, defined as persons who are mentally ill, mentally handicapped, or individuals without legal authority, are excluded from the study population