Non-invasive Mapping of Rhythm Disorders

This current care protocol is for 3 groups of patients :

1. Role of mapping arrhythmias before radiofrequency ablation :

Radiofrequency ablation is a treatment of atrial or ventricular arrhythmias resistant to drug treatment. The electrocardiogram does not allow a full diagnosis of arrhythmias and it appears difficult to get a comprehensive and simultaneous view of cardiac activity during invasive maps. The Investigators have demonstrated the feasibility of mapping atrial fibrillation and its usefulness to guide radiofrequency ablation. The non-invasive mapping would allow a better understanding of complex cardiac arrhythmias mechanism (atrial fibrillation, ventricular tachycardia and ventricular fibrillation in particular), would identify the arrhythmogenic sites and thus facilitate radiofrequency ablation. 2. Optimizing the site of implantation of cardiac pacing leads and programming the pacemaker:

The optimal position of the cardiac pacing leads may vary from one patient to another and the current choice of implantation sites is essentially guided by imaging and does not use power requirements because of the inadequacies of the ECG standard. The Investigators have already demonstrated the usefulness of non-invasive mapping in the selection of potential responders to cardiac resynchronization therapy. The non-invasive mapping would study the cardiac electrical activation in order to determine the optimal pacing sites and optimum programming according to each patient and thus improve the clinical response to pacing. 3. Role diagnostic and prognostic for patients referred for evaluation of the risk of occurrence of a serious rhythm disorder or sudden death :

The possibility to identify electrically abnormal areas either during the activation, or during cardiac repolarization with the high-resolution ECG is an indication of myocardial pathology that can be both unapparent on standard ECG and inaccessible to imaging techniques (ultrasound, CT or MRI). It is likely that such electrical anomalies are early diagnostic features of heart disease that will later be apparent. Such anomalies can also have an adverse prognostic weight (risk of arrhythmias or sudden death) that can be corrected if it is highlighted. Non-invasive mapping seems particularly important in patients with unexplained symptoms by conventional tests (palpitations or discomfort - syncope). It will also be applicable to patients with heart disease (myocardial infarction, cardiomyopathy) in search of localized electrical disorders that can be an originating site of arrhythmia.