Comparison of VF Induction Techniques During Medtronic ICD Implant (VF) (ICD) (VF)
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|ClinicalTrials.gov Identifier: NCT02027883|
Recruitment Status : Completed
First Posted : January 6, 2014
Results First Posted : December 30, 2014
Last Update Posted : May 22, 2018
As the indications for Implantable Cardioverter Defibrillator implantation expand, minimizing implant time is critical. Also, patients receiving biventricular ICDs are sometimes more unstable and minimization of sedation time is crucial. Multiple induction attempts, with a 1-Joule shock, can cause disruption in lead position. Therefore limiting the number of attempts will allow for better lead stability throughout the procedure and a more straightforward implant process.
Investigator proposes a detailed documentation of success rates from various Ventriculart Fibrillation induction methods during implant of Medtronic defibrillation capable devices.
|Condition or disease||Intervention/treatment||Phase|
|Cardiomyopathy||Device: Nominal T shock setting Device: Educated T shock setting||Not Applicable|
Our clinical experience has found that attempts to induce patients receiving ICDs at implant using the nominal Medtronic T-shock settings are not always effective at inducing ventricular fibrillation. When this results, a change to the parameters for T-shock is made before reattempting to induce ventricular fibrillation in patients undergoing ICD implantation.
Another available induction method is 50 Hz Burst. "The 50 Hz Burst induction is designed to induce VF by delivering a rapid burst of pacing pulses. The amplitude and pulse width of these pulses are selectable, but the pacing interval is fixed at 20 ms."2 If multiple attempts using the T-shock method are unsuccessful, 50 Hz Burst provides an additional method for inducing ventricular fibrillation. It is a less desirable method since it can result in very fine VF that is difficult to identify the initiation of possibly resulting in longer times in VF causing higher defibrillation threshold or in undersensing due to the fine nature of the rhythm.
T-shock has been found to be a fast and reliable method for inducing ventricular fibrillation in ICD implants. Greater success of inducing ventricular fibrillation using the T-shock method has been found when the energy of the T-shock was higher and the coupling interval was shorter. In addition, increasing the shock strength increases the window of vulnerability. For the T-shock method to be most efficient, initial success at inducing ventricular fibrillation, and therefore a reduced number of attempts, is important. This requires a better understanding of the optimal programmed settings for the initial T-shock induction attempt.
Moreover, in recent years, ICD indications have grown to include primary prevention patients. These patients may have different vulnerable periods than patients previously evaluated to develop Medtronic nominal settings.
Our clinical experience has found that the nominal T-shock settings are only effective at inducing ventricular fibrillation approximately seventy-five percent of the time. However, a detailed collection of success rates has not been performed.
|Study Type :||Interventional (Clinical Trial)|
|Actual Enrollment :||100 participants|
|Intervention Model:||Parallel Assignment|
|Masking:||None (Open Label)|
|Official Title:||Comparison of Ventricular Fibrillation Induction Techniques During Medtronic Implantable Cardioverter Defibrillator Implant|
|Study Start Date :||January 2011|
|Actual Primary Completion Date :||August 2012|
|Actual Study Completion Date :||August 2012|
Active Comparator: Nominal Parameter
Nominal T shock setting
Device: Nominal T shock setting
Nominal Parameter Set 1 Programming Values for EnTrust
Other Name: Medtronic ICDs
Experimental: Experimental Parameter
Educated T shock setting
Device: Educated T shock setting
Experimental Parameter Set 2 Programming Values
Other Name: Medtronic ICDs
- Sustained Ventricular Fibrillation [ Time Frame: 2 hours ]The primary endpoint is the successful induction of sustained ventricular fibrillation.
- Factors [ Time Frame: 2 hours ]Determine if any pre-implant patient demographics are factors impacting T-shock success according to parameter settings.
- Safety Monitoring [ Time Frame: 2 hours ]Number of participants that were monitored for safety issues, including increased heart rate, blood pressure, decreased oximetry levels, and stable rhythm during the entire procedure.
To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02027883
|United States, Tennessee|
|Wellmont CVA Heart Institute|
|Kingsport, Tennessee, United States, 37660|