Trial Outcomes & Findings for Precise Measurement of Pediatric Defibrillation Thresholds (NCT NCT01043562)

NCT ID: NCT01043562

Last Updated: 2018-02-05

Results Overview

The defibrillation threshold is a measure of the minimum amount of energy (in Joules) that is able to successfully defibrillate an episode of ventricular fibrillation. This measurement is specific to each individual patient with his/her specific defibrillator configuration. There are several different strategies to measuring this in an individual patient; this study utilized the binary search protocol.

Recruitment status

COMPLETED

Target enrollment

20 participants

Primary outcome timeframe

During clinical ICD procedure, as a single event

Results posted on

2018-02-05

Participant Flow

Participant milestones

Participant milestones
Measure
Pediatric ICD Pts
Inclusion criteria: 1) weight ≤60 kg, 2) new or existing ICD system, and 3) clinically necessary assessment of the defibrillation efficacy of the ICD system. Transvenous systems utilized a high-voltage ICD coil with active-fixation lead attached to the right ventricular endocardial surface, whereas non-transvenous systems depended upon a high-voltage shocking coil placed within the pericardial, subcutaneous or pleural space. To be included in the post-shock pacing portion of the study, adequate sinus and AV node function had to be present at baseline. Exclusion criteria included 1) tenuous hemodynamic status felt to warrant abbreviation of the defibrillation efficacy testing or 2) inability to induce fibrillation during defibrillation threshold testing (DFT). Defibrillator threshold testing: Measurement of the defibrillation threshold was performed using a modified binary search protocol. This protocol specified three distinct inductions of ventricula
Overall Study
STARTED
20
Overall Study
COMPLETED
20
Overall Study
NOT COMPLETED
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Precise Measurement of Pediatric Defibrillation Thresholds

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Pediatric ICD Pts
n=20 Participants
Inclusion criteria: 1) weight ≤60 kg, 2) new or existing ICD system, and 3) clinically necessary assessment of the defibrillation efficacy of the ICD system. Transvenous systems utilized a high-voltage ICD coil with active-fixation lead attached to the right ventricular endocardial surface, whereas non-transvenous systems depended upon a high-voltage shocking coil placed within the pericardial, subcutaneous or pleural space. To be included in the post-shock pacing portion of the study, adequate sinus and AV node function had to be present at baseline. Exclusion criteria included 1) tenuous hemodynamic status felt to warrant abbreviation of the defibrillation efficacy testing or 2) inability to induce fibrillation during defibrillation threshold testing (DFT). Defibrillator threshold testing: Measurement of the defibrillation threshold was performed using a modified binary search protocol. This protocol specified three distinct inductions of ventricula
Age, Continuous
16 years
n=99 Participants
Sex: Female, Male
Female
7 Participants
n=99 Participants
Sex: Female, Male
Male
13 Participants
n=99 Participants
Region of Enrollment
United States
20 Participants
n=99 Participants
Cardiac diagnosis
Channelopathy
11 Participants
n=99 Participants
Cardiac diagnosis
Congenital heart disease
5 Participants
n=99 Participants
Cardiac diagnosis
Cardiomyopathy
4 Participants
n=99 Participants
Weight (kg)
48 kilograms
n=99 Participants
ICD system configuration
Transvenous
12 Participants
n=99 Participants
ICD system configuration
Nontransvenous
8 Participants
n=99 Participants
Location of high-voltage coil
Transvenous single coil
7 Participants
n=99 Participants
Location of high-voltage coil
Transveous dual coil
5 Participants
n=99 Participants
Location of high-voltage coil
Pericardial
6 Participants
n=99 Participants
Location of high-voltage coil
Subcutaneous
1 Participants
n=99 Participants
Location of high-voltage coil
Pleural
1 Participants
n=99 Participants
Indication for defibrillation threshold testing
New implant
7 Participants
n=99 Participants
Indication for defibrillation threshold testing
Lead revision
5 Participants
n=99 Participants
Indication for defibrillation threshold testing
Generator change
5 Participants
n=99 Participants
Indication for defibrillation threshold testing
Surveillance
3 Participants
n=99 Participants
Anti-arrhythmic medications at testing
Beta-blocker
13 participants
n=99 Participants
Anti-arrhythmic medications at testing
Calcium-channel blocker
3 participants
n=99 Participants
Anti-arrhythmic medications at testing
Amiodarone
2 participants
n=99 Participants
Anti-arrhythmic medications at testing
Other
3 participants
n=99 Participants

PRIMARY outcome

Timeframe: During clinical ICD procedure, as a single event

The defibrillation threshold is a measure of the minimum amount of energy (in Joules) that is able to successfully defibrillate an episode of ventricular fibrillation. This measurement is specific to each individual patient with his/her specific defibrillator configuration. There are several different strategies to measuring this in an individual patient; this study utilized the binary search protocol.

Outcome measures

Outcome measures
Measure
Pediatric ICD Pts
n=20 Participants
Inclusion criteria: 1) weight ≤60 kg, 2) new or existing ICD system, and 3) clinically necessary assessment of the defibrillation efficacy of the ICD system. Transvenous systems utilized a high-voltage ICD coil with active-fixation lead attached to the right ventricular endocardial surface, whereas non-transvenous systems depended upon a high-voltage shocking coil placed within the pericardial, subcutaneous or pleural space. To be included in the post-shock pacing portion of the study, adequate sinus and AV node function had to be present at baseline. Exclusion criteria included 1) tenuous hemodynamic status felt to warrant abbreviation of the defibrillation efficacy testing or 2) inability to induce fibrillation during defibrillation threshold testing (DFT).
Non-transvenous ICDs
Patients with an implanted defibrillator system utilizing a nontransvenous high voltage coil/defibrillator lead.
Defibrillation Threshold
7 Joules
Interval 4.0 to 9.0

SECONDARY outcome

Timeframe: During clinical ICD procedure, as a single event

The defibrillation threshold (as measured in Joules as already described in the details regarding the primary outcome) will be compared between patients with two distinct general types of implanted defibrillator systems: 1) transvenous ICD systems (defibrillator leads located inside the vein and attached to the endocardial surface of the heart) and 2) non-transvenous ICD systems (including all other types of debrillation systems).

Outcome measures

Outcome measures
Measure
Pediatric ICD Pts
n=12 Participants
Inclusion criteria: 1) weight ≤60 kg, 2) new or existing ICD system, and 3) clinically necessary assessment of the defibrillation efficacy of the ICD system. Transvenous systems utilized a high-voltage ICD coil with active-fixation lead attached to the right ventricular endocardial surface, whereas non-transvenous systems depended upon a high-voltage shocking coil placed within the pericardial, subcutaneous or pleural space. To be included in the post-shock pacing portion of the study, adequate sinus and AV node function had to be present at baseline. Exclusion criteria included 1) tenuous hemodynamic status felt to warrant abbreviation of the defibrillation efficacy testing or 2) inability to induce fibrillation during defibrillation threshold testing (DFT).
Non-transvenous ICDs
n=8 Participants
Patients with an implanted defibrillator system utilizing a nontransvenous high voltage coil/defibrillator lead.
Do DFTs Vary by Type of ICD Systems Implanted?
7 Joules
Interval 4.5 to 11.0
6 Joules
Interval 3.5 to 9.0

SECONDARY outcome

Timeframe: During clinical ICD procedure, as a single event

Population: Post-defibrillation episodes in which intrinsic rhythm was evaluable and pacing was necessary

A patient will be considered to have an intrinsic slow heart rate in the period of time immediately following defibrillation (20 seconds) if any of the following are observed: \>7 paced beats, asystole \>4 seconds, or experienced \>10% decrease in systolic blood pressure.

Outcome measures

Outcome measures
Measure
Pediatric ICD Pts
n=49 Post-defibrillation episodes
Inclusion criteria: 1) weight ≤60 kg, 2) new or existing ICD system, and 3) clinically necessary assessment of the defibrillation efficacy of the ICD system. Transvenous systems utilized a high-voltage ICD coil with active-fixation lead attached to the right ventricular endocardial surface, whereas non-transvenous systems depended upon a high-voltage shocking coil placed within the pericardial, subcutaneous or pleural space. To be included in the post-shock pacing portion of the study, adequate sinus and AV node function had to be present at baseline. Exclusion criteria included 1) tenuous hemodynamic status felt to warrant abbreviation of the defibrillation efficacy testing or 2) inability to induce fibrillation during defibrillation threshold testing (DFT).
Non-transvenous ICDs
Patients with an implanted defibrillator system utilizing a nontransvenous high voltage coil/defibrillator lead.
Intrinsic Heart Rate in the Immediate Post-defibrillation Period
0 episodes

Adverse Events

Pediatric ICD Pts

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Andrew E. Radbill

Vanderbilt University (current institution)

Phone: 615-322-7447

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place