DANISH-CRT - Does Electric Targeted LV Lead Positioning Improve Outcome in Patients With Heart Failure and Prolonged QRS
DANISH-CRT - Does Electric Targeted LV Lead Positioning Improve Outcome in Patients With Heart Failure and Prolonged QRS
Heart failure is a leading cause of morbidity and mortality. Cardiac resynchronization
 therapy (CRT) is a well-established treatment for patients with symptomatic heart failure in
 spite of optimised medical treatment (OMT), reduced left ventricular pump function with left
 ventricular ejection fraction (LVEF) ≤ 35% and prolonged activation of the ventricles (bundle
 branch block: BBB). CRT is established by implanting an advanced pacemaker system with three
 leads in the right atrium, right ventricle, and in the coronary sinus (CS) for pacing the
 left ventricle (LV), and often is combined with an implantable defibrillator (ICD) function.
 On average, CRT treatment improves longevity, quality of life and functional class, and
 reduces heart failure symptoms. Thus, at present, CRT is indicated for heart failure patients
 on OMT with BBB or chronic right ventricular (RV) pacing.

 It is, however, a significant problem that 30-40% of CRT patients do not benefit measurably -
 showing symptomatic improvement or improved cardiac pump function - from this therapy
 (socalled non-responders). LV lead placement is one of the major determinants of beneficial
 effect from CRT.

 Observational studies and three randomised trials with small sample sizes indicate that
 targeted placement of the LV lead towards a late activated segment of the LV may be
 associated with improved outcome. Based on this literature, some physicians already search
 for late activation when positioning the LV lead. However, such a strategy was never tested
 in a controlled trial with a sample size sufficient to investigate important clinical
 outcomes. Detailed mapping for a late activation may increase operating times and infection
 risk, result in use of more electrodes and wires, thereby increasing costs, and increase
 radiation exposure for patient and staff. Placement of the LV lead in late activated areas
 close to myocardial scar may even result in higher risk of arrhythmia and death.

 At present, it is completely unsettled whether targeted positioning of the LV lead to the
 latest electrically activated area of LV is superior to contemporary standard CRT with regard
 to improving prognosis for patients with heart failure and BBB.

 The present study aims to test whether targeting the placement of the LV lead towards the
 latest electrically activated segment in the coronary sinus branches improves outcome as
 compared with standard LV lead implant in a patient population with heart failure and CRT
 indication.
Inclusion Criteria:

 -  Heart Failure, NYHA II, III, outpatient IV

 -  LVEF ≤35% measured by echocardiography

 -  Optimal medical treatment for heart failure

 -  Bundle Branch Block

 -  Indication for primary CRT-D or CRT-P implantation or upgrade from RV pacing
 (pacemaker or ICD) to CRT-D or CRT-P

 -  Ischemic heart disease (IHD) or non-IHD

 -  Sinus rhythm or atrial fibrillation

 -  Life expectancy >2 years

 -  Signed informed consent

 Exclusion Criteria:

 -  NYHA class I

 -  Acute mycardial infarction (AMI) within the latest 3 months

 -  Coronary artery bypass graft (CABG) within the latest 3 months

 -  Life expectancy <2 years

 -  Participation in another clinical trial of experimental treatment

 -  Contraindication for establishing implantable device treatment

 -  Previously implanted CRT system

 -  Does not wish to participate