The Rhytmia System to Determine the Precise Location and Potential Mechanism of Premature Contractions

Study Overview
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Brief Summary
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This is a purely observational project and the objectives are to record and analyze the local potentials at the site of Premature Ventricular Contraction (VPC) focus through the Rhythmia system, ti determine the short and long-term success of the procedure and compare it to the existing literature about standard procedures, to highlight the advantages of the system compared to conventional mapping and to characterize optimal pace map or activation map as achieved by the Rhythmia system.

Detailed Description
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This is a purely observational study. No special methodology choice, no comparison. The study want to find the determination of precise location of the focus and mechanisms involved constitutes a challenge for conventional electrophysiology, even with tridimensional systems, because of the time needed for accurate delineation of the location (due to the sometimes unfrequent Ventricular Premature Beats (VPB)) and to the insufficient mapping density or inadequate signal characteristics. The Rhythmia system could allow better determination of the focus location in relation to the anatomical structures, especially with unfrequent VPB, because of the available high density mapping due to the number of closed high-resolution electrodes located on the Orion catheter. Better delineation of the true focus origin and of the mechanisms involved (automaticity vs re-entry) may be of useful help for better understanding and efficient therapy.

Official Title
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Use of the Rhytmia System for Determining the Precise Location and Potential Mechanism of Premature Ventricular Contractions

Conditions
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Cardiac Arrhythmia, Cardiomyopathy, Dilated

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients with symptomatic monomorphic PVC with or without heart disease refractory to anti arrhythmic drugs patients with dilated cardiomyopathy and altered Left Ventricular Ejection Fraction (LVEF) suspected to be causes by frequent monomorphic VPC patients with malignant ventricular arrhythmias reproducibly induced by monomorphic PVC Exclusion Criteria: patients with non-symptomatic VPC and without cardiomyopathy patients under 18 yo pregnant women patients with polymorphic PVC arising from clearly different areas patient protected by the french law: guardianship and Trusteeship

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Determining the surface of optimal pace map or activation map | To evaluate the area of isochronal earliest activation of PVC (Premature Ventricular Contraction), based on unipolar or bipolar activation : correlations will be made with the suspected endocardial or epicardial/intra-mural location of the focus. This technic may reduce the area of perfect pace-mapping and possibly more accurately locate the focus. | One year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Record the local potentials at the site of PVC focus through the Rhythmia system | Pacing from any electrode being in close contact with the endocardial surface and comparing the paced QRS to the spontaneous VPC (automatic calculation available on Bard ElectroPhysiology (EP) system). Describe and analyze the local signals recorded from the Orion catheter at the site of the PVC focus. by looking for prepotentials as a surrogate of local abnormal automaticity, for local discrete scar and local late potentials favouring local reentry as a cause for PVC, determining the local activation characteristics of VPC (surface of local breakthrough, velocity and direction of activation. | One year | 
| Determine the short success of the procedure | Determine by repeated Holter recordings, and the relation to the findings made during the procedure (endocardial or suspected epicardial focus), mechanism | One year | 
| Determine long-term success of the procedure and compare it to the existing | Determine by repeated Holter recordings, and the relation to the findings made during the procedure (endocardial or suspected epicardial focus), mechanism | One year | 
| Characterize optimal pace map or activation map as achieved by the Rhythmia system | Evaluate the surface of perfect pace-mapping using the Orion catheter, by pacing from any electrode being in close contact with the endocardial surface and comparing the paced QRS to a template of the spontaneous VPC | One year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Rythmia system