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

Congestive Heart Failure Clinical Trial

— EXPECT  

Official title:

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

Clinical Trial Details — Status: Terminated

Administrative data

• NCT number: NCT01520714
• Other study ID #: 009-067
• Status: Terminated
• Phase: N/A
• First received: February 22, 2010
• Last updated: April 30, 2014
• Start date: December 2009
• Est. completion date: December 2011

Study information

• Verified date: April 2014
• Source: Baylor Research Institute
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

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

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.

Recruitment information / eligibility

• Status: Terminated
• Enrollment: 11
• Est. completion date: December 2011
• Est. primary completion date: December 2011
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

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 Design

Allocation: Randomized, Intervention Model: Parallel Assignment, Masking: Open Label

Related Conditions & MeSH terms

• Congestive Heart Failure
• Heart Failure

Intervention

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.

Locations

Country	Name	City	State
United States	The Heart Hospital in Plano	Plano	Texas

Sponsors (2)

Lead Sponsor	Collaborator
Baylor Research Institute	Medtronic

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Evidence of Change in Threshold of >1 Volt With Posture Changes		6 months	No