Trial Outcomes & Findings for Leadless Electrocardiogram (ECG) Evaluation Study (NCT NCT01297283)

NCT ID: NCT01297283

Last Updated: 2025-07-18

Results Overview

During CRT-P standard follow-up, ECG is used to determine atrial, left and right ventricular pacing thresholds. As primary endpoint, we will consider the proportion of patients for which for all leads LECG provides pacing threshold values that are clinically equivalent to those obtained with PECG taken as reference. The analysis will be performed on data collected at the 1-Month Follow-Up visit when the device pocket healing process is completed. Clinical equivalence will be defined as the LECG threshold values being no more than 0.5 volts different from the PECG threshold values.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

195 participants

Primary outcome timeframe

30 to 120 days

Results posted on

2025-07-18

Participant Flow

200 patients were enrolledand were followed for at least 1 month in 25 institutions in France (max 50 patients per center). The first patient was enrolled on 16th of September 2010. The last patient was enrolled on the 13th of September 2011. The last follow-up visit took place on 5th of December 2011.

The point of enrollment was defined as the time before device implant at which a patient has signed and dated the Informed Consent Form. At that point, the patient needed to be followed for the duration of the study (until the 1-Month Follow-Up visit) unless a Study Exit Form was completed.

Participant milestones

Participant milestones
Measure
Overall Subjects
Measurement of pacing thresholds are done first with the support of a leadless ECG provided by the implanted device
Overall Study
STARTED
195
Overall Study
COMPLETED
176
Overall Study
NOT COMPLETED
19

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Leadless Electrocardiogram (ECG) Evaluation Study

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Overall Subjects
n=195 Participants
Age, Continuous
80 years
n=5 Participants
Sex: Female, Male
Female
50 Participants
n=5 Participants
Sex: Female, Male
Male
145 Participants
n=5 Participants
BMC Index
24.75 kg/m²
n=5 Participants
Weight
71 Kilogramms
n=5 Participants
Height
1.69 meters
n=5 Participants
NYHA Class
Class I
6 participants
n=5 Participants
NYHA Class
Class II
41 participants
n=5 Participants
NYHA Class
Class III
105 participants
n=5 Participants
NYHA Class
Class IV
12 participants
n=5 Participants
NYHA Class
Not available
31 participants
n=5 Participants
LVEF
31 %
n=5 Participants
General cardiovascular history
Cardiomyopathy
187 participants
n=5 Participants
General cardiovascular history
Congenital Heart Disease
2 participants
n=5 Participants
General cardiovascular history
Congestive Heart Failure
29 participants
n=5 Participants
General cardiovascular history
Coronary artery disease
24 participants
n=5 Participants
General cardiovascular history
Hypertension
66 participants
n=5 Participants
General cardiovascular history
Myocardial infarction
25 participants
n=5 Participants
General cardiovascular history
Pulmonary hypertension (PH)
2 participants
n=5 Participants
General cardiovascular history
Valve dysfunction
26 participants
n=5 Participants
General cardiovascular history
Other cardiovascular history
17 participants
n=5 Participants
Cardiovascular Surgical History
NONE
65 participants
n=5 Participants
Cardiovascular Surgical History
Ablation
16 participants
n=5 Participants
Cardiovascular Surgical History
Coronary artery bypass graft (CABG)
11 participants
n=5 Participants
Cardiovascular Surgical History
Coronary artery intervention
43 participants
n=5 Participants
Cardiovascular Surgical History
Valve surgery
20 participants
n=5 Participants
Cardiovascular Surgical History
Other cardiovascular surgery
5 participants
n=5 Participants
Previous Device
CRT-D implant
6 participants
n=5 Participants
Previous Device
CRT-P implant
39 participants
n=5 Participants
Previous Device
ICD implant
1 participants
n=5 Participants
Previous Device
IPG implant
37 participants
n=5 Participants
Previous Device
other
5 participants
n=5 Participants
Atrial Arrhythmia History
NONE
86 participants
n=5 Participants
Atrial Arrhythmia History
Atrial fibrillation
99 participants
n=5 Participants
Atrial Arrhythmia History
Atrial flutter
12 participants
n=5 Participants
Atrial Arrhythmia History
Atrial tachycardia
1 participants
n=5 Participants
Atrial Arrhythmia History
Premature atrial complexes
1 participants
n=5 Participants
Atrial Arrhythmia History
Sinus node dysfunction
6 participants
n=5 Participants
Atrial Arrhythmia History
Supraventricular tachycardia
1 participants
n=5 Participants
Atrial Arrhythmia History
Other atrial arrhythmias
3 participants
n=5 Participants
Ventricular Arrhythmia History
NONE
174 participants
n=5 Participants
Ventricular Arrhythmia History
Premature ventricular complexes
7 participants
n=5 Participants
Ventricular Arrhythmia History
Torsades de pointes
1 participants
n=5 Participants
Ventricular Arrhythmia History
Ventricular asystole
1 participants
n=5 Participants
Ventricular Arrhythmia History
Ventricular flutter
1 participants
n=5 Participants
Ventricular Arrhythmia History
Ventricular tachycardia, non-sustained
6 participants
n=5 Participants
Ventricular Arrhythmia History
Ventricular tachycardia, sustained monomorphic
1 participants
n=5 Participants
Ventricular Arrhythmia History
Ventricular tachycardia, sustained, unknown morpho
2 participants
n=5 Participants
Ventricular Arrhythmia History
Other ventricular arrhythmias
3 participants
n=5 Participants
AV Junctional Arrhythmia History
NONE
44 participants
n=5 Participants
AV Junctional Arrhythmia History
1st degree AV block
31 participants
n=5 Participants
AV Junctional Arrhythmia History
2nd degree AV block
10 participants
n=5 Participants
AV Junctional Arrhythmia History
3rd degree AV block
43 participants
n=5 Participants
AV Junctional Arrhythmia History
Intermediate bundle branch block
4 participants
n=5 Participants
AV Junctional Arrhythmia History
Left bundle branch block
96 participants
n=5 Participants
AV Junctional Arrhythmia History
Right bundle branch block
15 participants
n=5 Participants
AV Junctional Arrhythmia History
Other AV junctional arrhythmias and blocks
5 participants
n=5 Participants

PRIMARY outcome

Timeframe: 30 to 120 days

During CRT-P standard follow-up, ECG is used to determine atrial, left and right ventricular pacing thresholds. As primary endpoint, we will consider the proportion of patients for which for all leads LECG provides pacing threshold values that are clinically equivalent to those obtained with PECG taken as reference. The analysis will be performed on data collected at the 1-Month Follow-Up visit when the device pocket healing process is completed. Clinical equivalence will be defined as the LECG threshold values being no more than 0.5 volts different from the PECG threshold values.

Outcome measures

Outcome measures
Measure
Overall Subjects
n=176 Participants
Proportion of Patients With LECG Performing Clinically Equivalent to PECG During Standard Pacemaker Follow-up Procedure.
LV Lead
0.98 proportion
95% Confidence Interval 1.19 • Interval 0.95 to 1.0
Proportion of Patients With LECG Performing Clinically Equivalent to PECG During Standard Pacemaker Follow-up Procedure.
All leads
0.96 proportion
Interval 0.92 to 0.98
Proportion of Patients With LECG Performing Clinically Equivalent to PECG During Standard Pacemaker Follow-up Procedure.
Atrial lead
0.99 proportion
95% Confidence Interval 0.41 • Interval 0.95 to 1.0
Proportion of Patients With LECG Performing Clinically Equivalent to PECG During Standard Pacemaker Follow-up Procedure.
RV Lead
0.98 proportion
95% Confidence Interval 0.56 • Interval 0.95 to 1.0

SECONDARY outcome

Timeframe: 30 to 120 days

Population: Proportion of Patients Correctly Classified

The investigator will simulate loss of capture (LOC) at 1-Month Follow-Up visit by printing strips of LOC in both ventricular leads, LOC in LV lead only, LOC in RV lead only, no LOC. One strip randomly selected among them by the study manager will be submitted to an independent reviewer. With help of the PHD template LECG strips (intrinsic, RV paced, LV paced, BiV paced) of this patient, he/she will determine which lead is capturing. The endpoint is the proportion of correct classifications of ventricular capture done by then independent reviewer of LECG.

Outcome measures

Outcome measures
Measure
Overall Subjects
n=176 Participants
Evaluation of the Possibility to Determine Ventricle Capture by an Independent Reviewer.
0.51 proportion
Interval 0.43 to 0.59

SECONDARY outcome

Timeframe: 30 to 120 days

Two parameters will be used to evaluate LECG changes between PHD and 1-Month on the same LECG vector: intrinsic R wave amplitude and P waves visibility (selection the LECG vector at PHD with best combination of the highest R wave and most visible P wave). R wave amplitude measurements as well as P wave visibility assessment will be done by the independent reviewer. The endpoints evaluated are: * mean R wave changes from PHD to 1-month * proportion of patients with stable P wave visibility at PHD and 1-Month (meaning both visits visible or both visits not visible).

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: 30 to 120 days

The two following parameters will be used to compare the quality of LECG in new implants versus device replacements at PHD and 1-Month on the same LECG vector: * Intrinsic R wave amplitude * P waves visibility The LECG vector at PHD with best combination of the highest R wave and most visible P wave will be selected. R wave amplitude measurements as well as P wave visibility assessment will be done by the independent reviewer. The endpoints will be: * comparison of mean R wave values at PHD and 1-month * comparison of proportion of patients with P wave visible at PHD and 1-month.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: 30 to 120 days

The intrinsic R wave amplitude and P waves visibility will be taken to evaluate the effect of posture changes and artifact-inducing maneuvers on the quality of LECG at the 1-Month Follow-Up visit (LECG vector with best combination of the highest R wave and most visible P wave). The endpoints will be R wave amplitude and P wave visibility in different positions (meaning visible or not visible in both positions). R wave changes and proportion of patients with stable P waves visibility at lying position versus other positions will be calculated by an independent reviewer.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: 30 to 120 days

The following factors will be evaluated to investigate whether they influence the LECG quality: * device position (subcutaneous, submuscular, etc) * device rotation * device fixation * device side facing the skin * position of lead loops in the pocket * use of antibiotics in the pocket * skin type (loose, normal, firm) * body mass index (BMI) The endpoints will be: * describe R wave amplitude values * describe proportion of patients with P wave visible on intrinsic LECG strips recorded at 1-Month FU.

Outcome measures

Outcome data not reported

Adverse Events

Overall Subjects

Serious events: 35 serious events
Other events: 3 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
Overall Subjects
n=195 participants at risk
Cardiac disorders
Cardiac decompensation / Global heart failure
3.1%
6/195 • Number of events 8
Cardiac disorders
Phrenic nerve stimulation
3.1%
6/195 • Number of events 6
Cardiac disorders
Atrial fibrillation
1.5%
3/195 • Number of events 3
Cardiac disorders
cardiogenic shock
1.5%
3/195 • Number of events 3
Cardiac disorders
AV node / His ablation
1.0%
2/195 • Number of events 2
Cardiac disorders
Pericardial effusion
0.51%
1/195 • Number of events 1
Cardiac disorders
LV lead dislodgement
0.51%
1/195 • Number of events 1
Cardiac disorders
LV lead threshold elevation
0.51%
1/195 • Number of events 1
Respiratory, thoracic and mediastinal disorders
Pneumothorax
1.0%
2/195 • Number of events 2
Respiratory, thoracic and mediastinal disorders
pulmonary edema
0.51%
1/195 • Number of events 1
Blood and lymphatic system disorders
anemia
0.51%
1/195 • Number of events 1
Skin and subcutaneous tissue disorders
Pocket hematoma
2.1%
4/195 • Number of events 4
Skin and subcutaneous tissue disorders
eczema
0.51%
1/195 • Number of events 1
Vascular disorders
Abdnominal aortic aneurysm
0.51%
1/195 • Number of events 1
Hepatobiliary disorders
hepatocellular failure
0.51%
1/195 • Number of events 1
Blood and lymphatic system disorders
allergy to iodine
0.51%
1/195 • Number of events 1
Endocrine disorders
hyperthyroidism
0.51%
1/195 • Number of events 1
General disorders
fever
0.51%
1/195 • Number of events 1
General disorders
multiviceral failure and cancer
0.51%
1/195 • Number of events 1
General disorders
general fatigue sensation and feet formications
0.51%
1/195 • Number of events 1

Other adverse events

Other adverse events
Measure
Overall Subjects
n=195 participants at risk
Cardiac disorders
coronary sinus dissection
0.51%
1/195 • Number of events 1
Blood and lymphatic system disorders
Slight deglobulisation
0.51%
1/195 • Number of events 1
Gastrointestinal disorders
colonic ischemia
0.51%
1/195 • Number of events 1

Additional Information

Latifa Foudali

Medtronic

Phone: +33 631992144

Results disclosure agreements

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