Optimal Coronary Sinus Lead Implantation Using Intracardiac Impedography and Magnetic Resonance Imaging
|Heart Failure, Systolic Left Bundle Branch Block||Procedure: Cardiac Resynchronization Therapy (CRT) implantation|
|Study Design:||Intervention Model: Single Group Assignment
Masking: None (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|
- 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 ]
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
- Differential correlation of Ts, Tp, and Td (see description) to the CMR dyssynchrony map. [ Time Frame: Acute intraoperative measurement ]
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).
|Study Start Date:||June 2010|
|Study Completion Date:||December 2014|
|Primary Completion Date:||August 2014 (Final data collection date for primary outcome measure)|
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
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:
- 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.
- LV lead impedograms vary significantly depending on LV lead location.
- There are several characteristics of LV lead impedograms that correlate with mechanical phenomena of the heart.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01129635
|United States, Georgia|
|Emory University Hospital|
|Atlanta, Georgia, United States, 30322|
|Principal Investigator:||Michael S. Lloyd, MD||Emory University|