Optimal Coronary Sinus Lead Implantation Using Intracardiac Impedography and Magnetic Resonance Imaging

This study is ongoing, but not recruiting participants.
Sponsor:
Information provided by (Responsible Party):
Michael S. Lloyd, Emory University
ClinicalTrials.gov Identifier:
NCT01129635
First received: May 5, 2010
Last updated: December 15, 2013
Last verified: December 2013
  Purpose

Despite the dramatic effect of cardiac resynchronization therapy (CRT) on survival and morbidity in people with congestive heart failure, 50-70% of eligible patients do not respond to this intervention. There is retrospective evidence that placement of the left ventricular (LV) lead at the region of latest mechanical delay markedly improves response to CRT. However, there is no feasible way to gauge dyssynchrony at LV lead sites during CRT implantation. Impedance recordings from pacing lead tips allow for real-time assessment of mechanical motion and may represent a useful intraoperative tool to guide optimum placement of the LV lead during CRT implantation. This pilot trial will assess the use of intraoperative impedograms in humans to measure regional dyssynchrony at potential LV lead locations during CRT implantation.


Condition Intervention
Heart Failure, Systolic
Left Bundle Branch Block
Procedure: Cardiac Resynchronization Therapy (CRT) implantation

Study Type: Interventional
Study Design: Endpoint Classification: Efficacy Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Real-Time Intracardiac Impedograms of Left Ventricular Leads to Locate Sites of Latest Mechanical Delay in Cardiac Resynchronization Therapy

Resource links provided by NLM:


Further study details as provided by Emory University:

Primary Outcome Measures:
  • Anatomic correlation between largest Ts (see description) and site of longest delay among probed locations in the CMR dyssynchrony map. [ Time Frame: Acute intraoperative measurement ] [ Designated as safety issue: No ]

    Parameter will be recorded for at least 10 consecutive heartbeats during sinus and RV paced rhythm

    Ts = The average time from the sensed RV IEGM to the peak of the LV impedance curve



Secondary Outcome Measures:
  • Differential correlation of Ts, Tp, and Td (see description) to the CMR dyssynchrony map. [ Time Frame: Acute intraoperative measurement ] [ Designated as safety issue: No ]

    Ts: The average time from the sensed RV IEGM to the peak of the LV impedance curve.

    Tp: The average time from the paced RV IEGM to the peak of the LV impedance curve.

    Td: The difference between Ts and Tp (Tp - Ts).



Enrollment: 38
Study Start Date: June 2010
Estimated Study Completion Date: December 2014
Estimated Primary Completion Date: August 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: CRT Candidate

Patients with NYHA Class III or IV heart failure; EF ≤ 30% and QRS duration ≥ 120 ms, who are scheduled for CRT surgery.

Intervention: Cardiac Resynchronization Therapy (CRT) implantation

Procedure: Cardiac Resynchronization Therapy (CRT) implantation

The impedance measurement is performed during device implantation following CMR. After the RV and LV leads are inserted, secured and tested, they will be connected to the impedance monitor. Impedance recording of at least ten beats will be acquired and stored for future analysis. Each recording will be tagged with the anatomical location of the LV lead. Subsequently, the LV lead will be moved to a different location and the same procedure will be repeated until accessible coronary sinus sites are exhausted. The ultimate LV lead location is determined by the implanting electrophysiologist and is not constrained by the study protocol. Finally, the LV lead will be tested again and the rest of the implantation procedure will proceed as routine.

Arm: CRT Candidate


Detailed Description:

This is a clinical trial using intracardiac impedance signals (impedograms) to assess regional dyssynchrony at various sites of left ventricular (LV) lead placement in humans undergoing CRT device implantation. This study will test the following hypotheses during the funding period:

  1. LV lead impedograms as an implant tool to place leads at sites of latest mechanical delay are feasible and correlate with other means of assessing dyssynchrony.
  2. LV lead impedograms vary significantly depending on LV lead location.
  3. There are several characteristics of LV lead impedograms that correlate with mechanical phenomena of the heart.
  Eligibility

Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Patients with NYHA class III or IV heart failure
  • LVEF ≤ 30%
  • QRS duration ≥ 120 ms

Exclusion Criteria:

  • Not a candidate for CRT implantation
  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 ClinicalTrials.gov identifier: NCT01129635

Locations
United States, Georgia
Emory University Hospital
Atlanta, Georgia, United States, 30322
Sponsors and Collaborators
Emory University
Investigators
Principal Investigator: Michael S. Lloyd, MD Emory University
  More Information

Publications:

Responsible Party: Michael S. Lloyd, PI, Emory University
ClinicalTrials.gov Identifier: NCT01129635     History of Changes
Other Study ID Numbers: IRB00036655, ACTSI-EP-001
Study First Received: May 5, 2010
Last Updated: December 15, 2013
Health Authority: United States: Institutional Review Board

Keywords provided by Emory University:
Heart failure
Cardiac resynchronization therapy
Regional left ventricular dyssynchrony
CRT

Additional relevant MeSH terms:
Heart Failure
Bundle-Branch Block
Heart Failure, Systolic
Heart Diseases
Cardiovascular Diseases
Heart Block
Arrhythmias, Cardiac
Pathologic Processes

ClinicalTrials.gov processed this record on October 19, 2014