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50/50% Tilt and Tuned Defibrillation Waveform

This study has been completed.
Information provided by:
St. Jude Medical Identifier:
First received: May 16, 2007
Last updated: March 30, 2011
Last verified: March 2011

Study Description The purpose of this study is to compare the defibrillation efficacy between the 50/50% tilt biphasic waveform and the Tuned biphasic waveform utilizing High Voltage Lead Integrity Check (HVLIC) impedance.

Hypothesis The Tuned waveform reduces defibrillation thresholds (DFTs) when compared to the 50/50% tilt waveform.

Study Methods

  • This is an acute, paired-sample, randomized (waveform testing sequence) study
  • Patients are implanted with an Food and Drug Administration (FDA) approved St. Jude Medical (SJM) EpicTM+ DR/VR Implantable Cardioverter Defibrillator (or any other standard output ICD after Epic+) and defibrillation lead system.
  • All study testing is completed at implant.
  • Patients are randomized to begin DFT testing with either the 50/50% tilt or Tuned waveform.
  • The HVLIC feature is used to measure the high voltage lead impedance and to program the Tuned and 50/50% tilt waveform pulse widths.
  • The DFT is determined by an optimized binary search method that is designed to reduce the overall number of VF inductions to an average of 5.13 while maintaining very high resolution and accuracy.
  • Total # of centers - 15 centers
  • Sample size - 60 patients

Condition Intervention
DFT Testing Procedure: DFT Testing with a 50/50% tilt

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Official Title: 50/50% Tilt and Tune Defibrillation Waveforms Utilizing High Voltage Lead Integrity Check Impedance

Further study details as provided by St. Jude Medical:

Study Start Date: January 2005
Study Completion Date: November 2005
Primary Completion Date: November 2005 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
50/50% Tilt Procedure: DFT Testing with a 50/50% tilt


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All

Inclusion Criteria:

  • Patient is a candidate for ICD implantation.
  • Patient is able to tolerate DFT testing.

Exclusion Criteria:

  • Patient has a mechanical valve in the tricuspid position.
  • Patient is pregnant.
  • Patient is less than 18 years old.
  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.

No Contacts or Locations Provided
  More Information

Responsible Party: Director, Clinical Affairs, St. Jude Medical Identifier: NCT01325922     History of Changes
Other Study ID Numbers: CRD 274
Study First Received: May 16, 2007
Last Updated: March 30, 2011 processed this record on September 21, 2017