Condition category
Circulatory System
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status
Results overdue

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Prof Jennifer Adgey


Contact details

Regional Medical Cardiology Centre
1st Floor West Wing
Royal Victoria Hospital
BT12 6BA
United Kingdom

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title


Study hypothesis

1. Electrocardiographic Imaging (ECGI) using potentials derived from the body surface can be used to identify electrical dyssynchrony within the Left Ventricle (LV), along with activation patterns and regions of slow conduction. It could therefore be used to predict response to cardiac resynchronisation therapy, and ultimately to guide placement of the LV pacing lead to the optimal site.
2. ECGI using body surface potentials acquired noninvasively is of comparable accuracy to endocardial data acquired invasively in determining sites of pacing of the LV endocardium and patterns of activation.
3. ECGI is comparable to endocardial data acquired invasively in locating the origin of Ventricular Tachycardia (VT) substrates and may provide useful information over and above endocardial data to aid radiofrequency ablation of this tachyarrhythmia.

Ethics approval

The Office for Research Ethics Committees in Northern Ireland (ORECNI), approved on 16/09/2005 (ref: 05/NIR01/139)

Study design

Non randomised controlled trial.

Primary study design


Secondary study design

Non randomised controlled trial

Trial setting


Trial type


Patient information sheet


Left ventricular dysfunction


1. CRT study
This is a pilot study during which 50 consecutive patients undergoing CRT implantation will be identified and worked up appropriately (there is no control group in this study and all participants will be given the same intervenions). All participants will undergo baseline assessment to include echocardiography, 6 minute walk testing, cardiopulmonary stress testing, quality of life assessment (questionnaire) and N-terminal Pro-BNP measurement. Body Surface Mapping (BSM) will be performed at baseline and the day following device implantation during different pacing modalities. They will then be followed up with a single visit at 6 months, at which time all of these tests will be repeated.

2. ECGI validation study:
A qualitative study comparing ECGI with data acquired invasively using noncontact endocardial mapping as gold standard. 10 patients undergoing invasive ElectroPhysiological Studies (EPS) requiring access to the left ventricle will be recruited. All patients will have an ECHO at baseline and undergo simultaneous body surface mapping and invasive endocardial mapping during muti-site pacing of the LV endocardium. BSM utilises a plastic 80-electrode mapping harness applied to the anterior and posterior torso. Noncontact endocardial mapping uses the previously validated EnSite 3000 system. This study will enable a qualitative comparison of both imaging modalities for localisation of pacing sites as well as activation sequences. There will be no follow-up for the patients in this sub-study.

3. VT study:
10 patients requiring VT ablation or simply EPS for induction of ventricular arrhythmias will be studied using both invasive and noninvasive modalities. This is a purely qualitative study.

Intervention type



Not Specified

Drug names

Primary outcome measure

CRT study:
Response to CRT (assessed clinically using echo, 6 minute walk distance, cardiopulmonary stress testing, and functionally using quality of life questionnaire and NYHA symptom class). This can be assessed in conjunction with pacing site localisation using ECGI in relation to regions of slow conduction/scar tissue.

ECGI validation and VT studies: These are qualitative studies whereby ECGI data and data acquired invasively are compared directly. Therefore there is no discrete end-point.

Secondary outcome measures

No secondary outcome measures

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

Cardiac Resynchronization Therapy (CRT) study:
1. Poor LV function with ejection fraction on echocardiogram (ECHO) <35%
2. Symptomatic with New York Heart Association (NYHA) class 2-4
3. Dilated LV (>55 mm)
4. Any QRS duration (representing the duration of ventricular depolarisation)
LV dysfunction can be of any aetiology. All patients must be able and willing to give writted informed consent.

ECGI validation study:
Patients must require EPS/ablation of tachyarrhythmias requiring LV access e.g. VT ablation/EPS, Brugada EPS, left sided pathways. All must be willing and able to give written informed consent.

VT study:
All patients must require EPS for induction of LV tachyarrhythmias or ablation of VT. Again all must give written informed consent.

Participant type


Age group



Not Specified

Target number of participants

70 (CRT study, 50; ECGI validation study, 10; VT study, 10)

Participant exclusion criteria

CRT study:
1. Ejection fraction on ECHO >35%
2. Unable or unwilling to come back for 6 month follow-up
3. Unable or unwilling to give written informed consent

ECGI validation and VT studies:
1. Procedures not requiring access to the LV
2. Bleeding conditions
3. Clotting disorders
4. Unwilling to give written informed consent
5. Age <18 years

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Regional Medical Cardiology Centre
BT12 6BA
United Kingdom

Sponsor information


Royal Victoria Hospital (UK)

Sponsor details

c/o Professor Ian Young
Royal Research Office
Royal Victoria Hospital
Grosvenor Road
BT12 6BA
United Kingdom

Sponsor type

Hospital/treatment centre



Funder type

Not defined

Funder name

Frances and Augustus Newman Foundation (UK)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

Shannon HJ, Navarro CO, Smith B, McClelland, AJ, Lau EW, Roberts MJD, Anderson JM, Adgey AAJ. Activation Patterns during Selective Pacing of the Left Ventricle can be Characterised using Noninvasive Electrocardiographic Imaging (in press) Journal of Electrocardiology, 2007

Publication citations

Additional files

Editorial Notes