Contractile Reserve in Dyssynchrony: A Novel Principle to Identify Candidates for Cardiac Resynchronization Therapy

Contractile Reserve in Dyssynchrony (CRID): A Novel Principle to Identify Candidates for Cardiac Resynchronization Therapy

Cardiac resynchronisation therapy (CRT) has been documented to be a powerful treatment in patients with severe congestive heart failure. However, 30-40% of patients receiving a CRT are non-responders. In this study the investigators will use a previously validated method to estimate myocardial segment work non-invasively by speckle-tracking echocardiography and blood pressure. Furthermore, cardiac magnetic resonance imaging (CMR) with late gadolinium enhancement (LGE) will be performed in feasible subjects. The main purpose of the study is to determine if myocardial work by echocardiography in combination with viability assessment by LGE-CMR can predict response to CRT.

Inclusion Criteria:

• Subject is indicated for CRT device according to European Society of Cardiology (ESC) guidelines from 2013.
• Subject is willing to sign informed consent form and is 18 years or older.

Exclusion Criteria:

• Right bundle branch block.
• Recent myocardial infarction, within 40 days prior to enrollment.
• Subject underwent coronary artery bypass graft (CABG) or valve surgery, within 90 days.
• Post heart transplantation, or is actively listed on the transplantation list, or has reasonable probability (per investigator's discretion) of undergoing transplantation in the next year
• Implanted with a LV assist device (LVAD), or has reasonable probability (per investigator's discretion) of receiving a LVAD in the next year
• Severe aortic stenosis (with a valve area of <1.0 cm2 or significant valve disease expected to be operated on within study period).
• Complex and uncorrected congenital heart disease.
• Breastfeeding women or women of child bearing potential.
• Enrolled in one or more concurrent studies that would confound the results of this study.
• Impossible to obtain LV volumes by echocardiography