Randomized Clinical Trial of MRI for Optimal CRT Outcomes

At baseline, patients will have CMR, echocardiography, and cardiopulmonary exercise testing.
In patients randomized to CMR guidance for the CRT procedure, LV lead placement will be
guided by the MRI information related to scar, activation and anatomy. Patients will have
follow-up assessments at 6 and 12 months.

Inclusion Criteria:

1. chronic systolic HF

2. LVEF 35% or less, and a guideline-based class I or II indication for CRT 3) 3) They
must be between 20 and 90 years old

4) Predominantly in sinus rhythm 5) The GFR must be at least 45 cc/min if the patient is to
receive gadolinium

Exclusion Criteria:

1. inability to provide informed consent

2. pregnancy

3. presence of metal embedded in the body due to prior accident or injury, as documented
by skull films or other imaging;

4. cerebral aneurysm clips

5. gadolinium contrast allergy (only if gadolinium is given)

6. cochlear implants

7. other metallic implants known to be contraindications to MRI

8. severe claustrophobia

9. acute kidney injury

10. acute renal failure or chronic kidney disease with GFR < 40 cc/min

11. liver transplant

12. gadolinium contrast allergy