Effect of Posture on Left Ventricular (LV) Transvenous Lead Capture Thresholds (EXPECT) (EXPECT)

Effect of Posture on LV Transvenous Lead Capture Thresholds (EXPECT)

The purpose of this study is to determine whether changes in a patient's position affect LV capture thresholds in a clinically significant way.

Study Overview

• Status: Terminated
• Conditions: Congestive Heart Failure
• Intervention / Treatment: Device: Medtronic 4195 active fixation LV lead and Medtronic passive fixation LV lead

Detailed Description

Traditionally clinicians program the safety margins for the right atrial, right ventricular, and left ventricular leads two-times the capture thresholds. This safety margin is necessary for the right atrial and right ventricular outputs to prevent asystole during fluctuation of capture thresholds. This two-times safety margin may not be necessary for the left ventricular lead output and may be causing shorter device battery longevity. Newly implemented LV capture threshold management algorithms may help maintain a proper balance of safety margin and battery longevity. However, recent research conducted on automatic left ventricular capture measurement (LVCM) shows as much as 3.5 V daily variability in capture thresholds. In this same study, 18% of patients had >1.5 V LV threshold variability. A possible explanation for the variability of LV thresholds is lead stability. Small movements of the lead electrodes associated with movement of patient posture may account for daily fluctuation of capture thresholds. As heart failure patient care and therapies improve, CRT patients may survive longer than the projected longevities of their device. In order to minimize patient risks associated with device change-outs, care must be taken to maximize battery longevity while maintaining CRT pacing. Examining patient posture changes as a possible cause of threshold variability may guide clinicians to program more appropriate LV outputs with patient safety and device longevity in mind.

• Study Type: Interventional
• Enrollment (Actual): 11
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Texas
    • Plano, Texas, United States, 75093
      • The Heart Hospital in Plano

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:

• Greater than 18 years of age and able to provide informed consent
• Planned placement of a Medtronic LV pacing lead and a Medtronic ICD generator with LVCM technology
• Geographically stable and able to follow-up for a period of at least six months post-procedure at The Heart Hospital Baylor Plano
• Willingness to comply with the requirements of the protocol

Exclusion Criteria:

• Life expectancy of less than six months
• Plans for or significant possibility of pregnancy during the required follow-up window
• Significant cardiovascular surgery planned within six months following ICD implant

Study Plan

How is the study designed?

Design Details

• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Medtronic passive fixation LV lead; Medtronic 4195 Active Fixation LV lead and Medtronic passive fixation LV lead arms will both have same follow-up testing and schedule	Device: Medtronic 4195 active fixation LV lead and Medtronic passive fixation LV lead; 1:1 randomization between Medtronic active fixation 4195 LV lead and another FDA approved passive fixation Medtronic LV lead. Fluoroscopic images will be taken at implant in a supine position and again at 3 month follow-up in different postural positions with capture thresholds of the LV lead taken at each postural position.
Experimental: Medtronic 4195 Active Fixation LV Lead; Medtronic 4195 Active Fixation LV lead and Medtronic passive fixation LV lead arms will both have same follow-up testing and schedule	Device: Medtronic 4195 active fixation LV lead and Medtronic passive fixation LV lead; 1:1 randomization between Medtronic active fixation 4195 LV lead and another FDA approved passive fixation Medtronic LV lead. Fluoroscopic images will be taken at implant in a supine position and again at 3 month follow-up in different postural positions with capture thresholds of the LV lead taken at each postural position.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Evidence of Change in Threshold of >1 Volt With Posture Changes	6 months

Collaborators and Investigators

• Sponsor: Baylor Research Institute
• Collaborators: Medtronic
• Investigators: Principal Investigator: James B DeVille, M.D., Baylor Research Institute - The Heart Hospital Baylor Plano

Study record dates

Study Major Dates

• Study Start: December 1, 2009
• Primary Completion (Actual): December 1, 2011
• Study Completion (Actual): December 1, 2011

Study Registration Dates

• First Submitted: February 22, 2010
• First Submitted That Met QC Criteria: January 26, 2012
• First Posted (Estimate): January 30, 2012

Study Record Updates

• Last Update Posted (Estimate): May 26, 2014
• Last Update Submitted That Met QC Criteria: April 30, 2014
• Last Verified: April 1, 2014

More Information

Terms related to this study

• Keywords: Congestive Heart Failure (CHF); Fraction; Cardiac Resynchronization Therapy (CRT); BiVentricular Implantable Cardioverter Defibrillator (BiVICD)
• Additional Relevant MeSH Terms: Heart Diseases; Cardiovascular Diseases; Heart Failure
• Other Study ID Numbers: 009-067