Real-Time Intracardiac Impedograms of Left Ventricular Leads to Locate Sites of Latest Mechanical Delay in Cardiac Resynchronization Therapy
Overview
- Phase
- N/A
- Intervention
- Not specified
- Conditions
- Heart Failure, Systolic
- Sponsor
- Emory University
- Enrollment
- 38
- Locations
- 1
- Primary Endpoint
- Anatomic correlation between largest Ts (see description) and site of longest delay among probed locations in the CMR dyssynchrony map.
- Status
- Completed
- Last Updated
- 11 years ago
Overview
Brief Summary
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.
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.
Investigators
Michael S. Lloyd
PI
Emory University
Eligibility 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
Outcomes
Primary Outcomes
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
Secondary Outcomes
- Differential correlation of Ts, Tp, and Td (see description) to the CMR dyssynchrony map.(Acute intraoperative measurement)