This site became the new on June 19th. Learn more.
Show more Menu IMPORTANT: Listing of a study on this site does not reflect endorsement by the National Institutes of Health. Talk with a trusted healthcare professional before volunteering for a study. Read more... Menu IMPORTANT: Talk with a trusted healthcare professional before volunteering for a study. Read more... Menu
Give us feedback

Localization of CRT According to Echocardiography: LOCATE-Pilot Study

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified November 2006 by Michigan Heart, PC.
Recruitment status was:  Active, not recruiting
Information provided by:
Michigan Heart, PC Identifier:
First received: October 5, 2005
Last updated: November 2, 2006
Last verified: November 2006
Currently, the majority of heart failure patients who qualify for and receive a cardiac resynchronization therapy (CRT) device feel better than before their implant. However, there are some patients who do not improve after the implant. Michigan Heart is sponsoring a research study called LOCATE-Pilot to help understand whether the information from an echocardiogram, performed before implanting the CRT device, improves patients’ responses to CRT. This is being done by evaluating your heart’s function with an echocardiogram, to measure your heart’s response during therapy. The study hypothesis is that response to CRT may be optimized by guiding left ventricular lead placement to the maximally delayed, viable basal segment of the left ventricle.

Condition Intervention
Heart Failure Procedure: Echocardiogram guided left ventricular lead placement

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double
Primary Purpose: Treatment
Official Title: Localization of CRT According to Echocardiography: LOCATE-Pilot Study

Resource links provided by NLM:

Further study details as provided by Michigan Heart, PC:

Primary Outcome Measures:
  • Efficacy: Indexed end systolic volume decrease>15% by biplane Simpson's technique at 6 month follow-up.
  • Safety: CRT implantation morbidity; mortality

Secondary Outcome Measures:
  • Clinical composite (6 month clinical assessment in HF clinic): 6 minute hall walk distance, MLWHF QOL score, NYHA functional classification
  • Clinical outcome at study termination (6 month follow-up for last patient enrolled): vital status (all cause mortality), cardiac mortality, unplanned hospitalization for major cardiovascular event
  • Proportion of diagnostic pulsed wave Doppler baseline studies
  • Success rate at Echo guided implantation (implantation of LV lead to target segment)
  • Outcomes stratified by concordance (pacing most delayed, viable segment)

Estimated Enrollment: 60
Study Start Date: September 2005
Estimated Study Completion Date: April 2007
Detailed Description:

CRT is a promising treatment modality for medically-refractory New York Heart Association (NYHA) class III or IV heart failure (HF) patients with intraventricular conduction delay (QRS > 130 ms). The randomized trials also suggest that a substantial minority of patients do not benefit, either echocardiographically or clinically, from CRT. In the MIRACLE trial, for instance, 35% of patients did not clinically improve after CRT. Objective reverse remodeling, typically defined as >15% reduction in the end-systolic volume, occurs in approximately 60% of patients. Most echocardiographic studies to date have reported only short- and intermediate-term results.

The objectives of the LOCATE-Pilot study are as follows: 1) to determine the proportion of patients undergoing CRT or CRT with defibrillator (CRT-D) with interpretable pulsed-wave tissue Doppler echocardiographic signals to quantitate and localize mechanical dyssynchrony; 2) to determine how frequently the LV lead can be successfully implanted in the most delayed basal segment (area of maximal delay); 3) to determine whether TDI guidance of CRT improves the proportion of patients with an echocardiographic response to treatment (reverse remodeling) at 6 months; 4) to determine whether TDI guidance of CRT improves the proportion of patients with a clinical response to treatment (6 min walk time, major clinical vascular events, or Minnesota Living with Heart Failure Quality of Life score); 5) to confirm that echocardiographic targeting of LV lead implantation is safe and does not hamper efficiency in the electrophysiological laboratory; 6) to validate the peak velocity delay (PVD) as a predictor of CRT response using pulsed-wave Doppler tissue imaging.

The LOCATE-pilot is a randomized, prospective study of 60 patients undergoing implantation of a Medtronic market approved CRT system. All patients will undergo a comprehensive baseline echocardiographic study in which a 6-segment model will be used to quantify dyssynchrony by the pulsed-wave Doppler technique. Myocardial viability will be assessed by conventional 2D criteria and nuclear perfusion data when available. Patients will be randomized to 1 of 2 groups with 30 patients per group on an intention-to-treat basis: 1) Control group: the implanting physician will have no knowledge of the baseline dyssynchrony assessment and use the current standard of care in the LV lead implantation; and 2) Echo-Guided group: the implanting physician will have full knowledge of baseline echocardiographic study and will use the dyssynchrony and viability data to guide final LV lead placement.

For this pilot study, patients will be followed for 6 months with a repeat Echocardiogram at 6 months. The primary endpoint of the study is indexed end systolic volume decrease >15% by biplane Simpson’s technique.


Ages Eligible for Study:   18 Years to 80 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • male/female patients
  • NYHA class III and IV chronic heart failure
  • symptoms refractory to standard therapy (beta blocker and either ACE-I or ARB on stable dosages for 1 month minimum and duration of 3 months therapy minimum)
  • patient has signed and dated informed consent
  • patient able to receive pectoral device implant
  • QRS>= 130 ms
  • EF <= 35%
  • follow-up at Michigan Heart CHF clinic feasible
  • patient understanding of protocol and willing to comply

Exclusion Criteria:

  • recent myocardial infarction (<3 months)
  • recent surgical or percutaneous revascularization (<3months)
  • age < 18 months
  • permanent AF without AV junction ablation
  • life expectancy under 6 months
  • women of child-bearing potential and not willing or able to take birth control
  • mechanical tricuspid valve
  • prior orthotopic heart transplantation
  • intermittent inotropic therapy or inotropic-dependent
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00234611

United States, Michigan
Michigan Heart, PC
Ypsilanti, Michigan, United States, 48197
Sponsors and Collaborators
Michigan Heart, PC
Principal Investigator: Steven E Girard, MD, PhD Michigan Heart, PC
  More Information

Publications: Identifier: NCT00234611     History of Changes
Other Study ID Numbers: MH-MDT-01
Study First Received: October 5, 2005
Last Updated: November 2, 2006

Additional relevant MeSH terms:
Heart Failure
Heart Diseases
Cardiovascular Diseases processed this record on August 21, 2017