Evaluation of Resynchronization Therapy for Heart Failure (EARTH)

EvaluAtion of Resynchronization Therapy for Heart Failure (EARTH)

Heart failure is a major health problem in Canada. Recent advances in medical and device therapy have helped to reduce the morbidity and mortality of patients with this problem. Among these treatments, cardiac resynchronization therapy (CRT) has very recently been shown to be effective to improve functional class, quality of life and exercise tolerance of the patients with the most severe symptoms of heart failure and a prolonged duration of the QRS on the 12-lead Electrocardiography (ECG).

Study Overview

• Status: Terminated
• Conditions: Heart Failure
• Intervention / Treatment: Device: CRT on; Device: CRT off

Detailed Description

Resynchronization of the failing ventricle is currently achieved by pacing the left and right ventricles simultaneously with specialized electrodes and a cardiac stimulator. However, controversy persists concerning the optimal configuration for cardiac pacing in these patients. Right ventricular pacing alone has been shown to be deleterious in some patient populations. The benefits of biventricular pacing in heart failure patients may be due primarily to left ventricular stimulation and may, in some patients, be decreased by the presence of simultaneous RV stimulation. Preliminary data from our own animal work suggest that in the majority of cases, LV stimulation alone is better than RV stimulation, and that BiV stimulation represents an intermediary situation between LV and RV stimulation.

• Study Type: Interventional
• Enrollment (Anticipated): 120
• Phase: Phase 4

Contacts and Locations

Study Locations

• Canada
  • Alberta
    • Edmonton, Alberta, Canada, T6G 2B7
      • University of Alberta Hospital
  • Nova Scotia
    • Halifax, Nova Scotia, Canada, B3H 3A7
      • QEII Health Sciences Centre
  • Ontario
    • Hamilton, Ontario, Canada, L8L 2X2
      • Hamilton Health Sciences Center
    • Ottawa, Ontario, Canada, K1Y 4W7
      • University of Ottawa Heart Institute
    • Toronto, Ontario, Canada, M5B 1W8
      • St-Michael's Hospital
    • Toronto, Ontario, Canada, M4N 3M5
      • Sunnybrook & Women's Hospital
  • Quebec
    • Fleurimont, Quebec, Canada, J1H 5N4
      • CHUS-Fleurimont
    • Montreal, Quebec, Canada, HIT1C8
      • Montreal Heart Institute Research Center
    • Montréal, Quebec, Canada, H2W 1T8
      • CHUM-Hôpital Hotel-Dieu
    • Montréal, Quebec, Canada, H4J 1C5
      • Sacre-Coeur Hospital
    • Québec, Quebec, Canada, G1V 4G5
      • Institut Univ de Cardiologie et de Pneumologie de Québec

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• The patients are eligible if they undergo an ICD implantation or replacement
• They have a documented LVEF ≤ 35% measured in the previous 6 months (without major clinical subsequent event, such as heart surgery, since the LVEF measurement)
• If measured by echocardiography, the LV end-diastolic diameter must be ≥ 60 mm
• The duration of the QRS is < 120 ms
• They are in sinus rhythm
• They cannot walk more than 400 meters during the screening 6-minute walk test (the patients must be limited by heart failure symptoms)

Exclusion Criteria:

• Patients with an indication for permanent ventricular pacing or with chronotropic insufficiency defined as follow:

  • Any condition where the treating physician believes it would not be acceptable for the patient to have his device NOT programmed with the SENSOR at ON for the duration of the study
  • Second or third degree AV block, either persistent or intermittent
  • Patients with a pacemaker or an ICD who are paced in the ventricular chamber more than 5% of the time
• Patients with LV dysfunction associated with a reversible cause such as post-partum cardiomyopathy, tachycardia induced cardiomyopathy, acute myocarditis or acute toxic cardiomyopathy (including acute alcoholic)

• Patients who had a myocardial infarction within the past 6 weeks* defined by 2 of the 3 following conditions:

  • Prolonged chest pain
  • ECG changes suggesting of AMI
  • Cardiac enzymes elevation more than twice the local upper limit of normal)
• Patients who had cardiac surgery within the past 6 weeks*
• Patients with moderate or severe cardiac valve stenosis (aortic, mitral, pulmonary or tricuspid)
• Patients with an inability or a limitation to walk for reasons other than heart failure symptoms (e.g., angina, intermittent claudication, severe lung condition or arthrosis)
• Patients with severe coexisting illnesses making survival > 6 months unlikely
• Patients who are pregnant and/or nursing.
• Patients with inability or unwillingness to consent or comply with follow-up requirements
• Patients participating in another study

The 6-week period is calculated prior to the beginning of the baseline evaluation and not the implant procedure itself. This difference comes from the fact that the protocol includes a delay of 2 to 8 weeks between the implant procedure and the actual beginning of the patient's evaluation.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: CRT	Device: CRT on; 12 months
Sham Comparator: No CRT	Device: CRT off; 12-month

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Total exercise duration at a constant submaximal load (defined as 75% of peak exercise during the baseline metabolic evaluation); study is powered to detect a min difference of 300 sec (+25% from baseline) in the primary endpoint between the 2 treatments	one year

Secondary Outcome Measures

Outcome Measure	Time Frame
Clinical & electrical endpoints and echocardiographic & nuclear medicine evaluation of LV function. Dyssynchrony evaluation will help advancing the understanding of the physiopathology of heart failure and response to resynchronization therapy.	one year

Collaborators and Investigators

• Sponsor: Montreal Heart Institute
• Collaborators: Canadian Institutes of Health Research (CIHR); Abbott Medical Devices
• Investigators: Study Chair: Bernard Thibault, MD, Montreal Heart Institute

Publications and helpful links

General Publications

• Thibault B, Harel F, Ducharme A, White M, Ellenbogen KA, Frasure-Smith N, Roy D, Philippon F, Dorian P, Talajic M, Dubuc M, Guerra PG, Macle L, Rivard L, Andrade J, Khairy P; LESSER-EARTH Investigators. Cardiac resynchronization therapy in patients with heart failure and a QRS complex <120 milliseconds: the Evaluation of Resynchronization Therapy for Heart Failure (LESSER-EARTH) trial. Circulation. 2013 Feb 26;127(8):873-81. doi: 10.1161/CIRCULATIONAHA.112.001239. Epub 2013 Feb 6.

Study record dates

Study Major Dates

• Study Start: October 1, 2003
• Primary Completion (Actual): February 1, 2011
• Study Completion (Actual): July 1, 2011

Study Registration Dates

• First Submitted: May 12, 2009
• First Submitted That Met QC Criteria: May 12, 2009
• First Posted (Estimate): May 13, 2009

Study Record Updates

• Last Update Posted (Estimate): July 21, 2011
• Last Update Submitted That Met QC Criteria: July 20, 2011
• Last Verified: July 1, 2011

More Information

Terms related to this study

• Keywords: Heart failure; ICD; Cardiac resynchronization therapy
• Additional Relevant MeSH Terms: Heart Diseases; Cardiovascular Diseases; Heart Failure
• Other Study ID Numbers: UCT67914 (Lesser Earth); ISRCTN 42560370