Non-Invasive epiCardial and Endocardial mapping of Idiopathic Ventricular Arrhythmias

Rationale
Idiopathic ventricular arrhythmias mostly originate in the outflow area of the heart.
This is a complex anatomic area consisting of the right ventricular outflow tract,
pulmonic artery, left ventricular outflow tract, aortic cusps, coronary sinus as well as
the cardiac veins, mitral annulus and epicardial anterior crux.
Detailed data on the site of origin obtained by a non-invasive mapping tool such as
integrated electrocardiographic mapping prior to the procedure may facilitate future
mapping procedure by narrowing down the number of potential anatomical structures
from which the ventricular ectopy may originate.
Thus, procedure time can be shortened in addition to achieving a reduction in the
number of anatomical structures that needs to be mapped invasively.

Objective
Non-invasive localization of the origin of idiopathic ventricular arrhythmias

Study design
Observational study

Study population
Patients eligible for radiofrequency catheter ablation of idiopathic ventricular extrasystole and/or (non-)sustained monomorphic ventricular tachycardia, who are able to comprehend the study purposes as well as procedure and provide us with informed consent.

Intervention
Patients who are scheduled to undergo radiofrequency ablation of symptomatic, idiopathic ventricular ectopy are eligible for this study. All patients will undergo cardiac (diffusion-) magnetic resonance imaging (MRI) as part of standard workup before ablation.
Prior to electrophysiology study, an extended, 64-channel, body surface electrocardiogram of the spontaneous ventricular ectopy will be obtained. This ECG-data combined with findings of MRI will be fed into a mathematical model capable of reconstructing epicardial and endocardial activation maps to estimate the site of origin of the ventricular ectopy.

Main study parameters/endpoints
Two primary endpoints have been established.
First, measure of agreement between the calculated origin of ventricular arrhythmia via our mathematical model versus observed origin of ventricular arrhythmia as Rhythmia© mapping system.
Second, accuracy of the NI-ECG in predicting the origin of ventricular arrhythmia by calculating the mean difference in millimetres between observed site of origin and calculated site of origin.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness:
Patients will have to undergo one additional extended body surface
electrocardiographic (ECG) registration by means of a 64-electrode set. A MRI will be
performed as part of standard clinical care and it will be used to reconstruct cardiac
and thoracic anatomy as well as geometry. There is no additional
risk to our patient population, since no additional invasive procedures are required.
All patients will receive standard care prior to, during and after procedure.
There is no direct potential benefit of participating in this study. Future mapping
procedures may become more efficient, since endocardial and epicardial activation have
been visualized prior to start of the ablation procedure.

We hypothesize our body surface mapping system will be able to detect origin of idiopathic ventricular arrhythmia with high accuracy.

Submitted to METC Twente

Prior to electrophysiology study, an extended, 64-channel, body surface electrocardiogram of the spontaneous ventricular ectopy will be obtained. This ECG-data combined with findings of MRI will be fed into a mathematical model capable of reconstructing epicardial and endocardial activation maps to estimate the site of origin of the ventricular ectopy.