Pierre Jais

2012 HRS/EHRA/ECAS expert consensus statement on catheter and surgical ablation of atrial fibrillation: recommendations for patient selection, procedural techniques, patient management and follow-up, definitions, endpoints, and research trial design

This is a report of the Heart Rhythm Society (HRS) Task Force on Catheter and Surgical Ablation of Atrial Fibrillation, developed in partnership with the European Heart Rhythm Association (EHRA), a registered branch of the European Society of Cardiology and the European Cardiac Arrhythmia Society (ECAS), and in collaboration with the American College of Cardiology (ACC), American Heart Association (AHA), the Asia Pacific Heart Rhythm Society (APHRS), and the Society of Thoracic Surgeons (STS). This is endorsed by the governing bodies of the ACC Foundation, the AHA, the ECAS, the EHRA, the STS, the APHRS, and the HRS.

Chapter 112 – Catheter Ablation of Atrial Fibrillation: Triggers and Substrate

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia in humans, occurring in 2% of the unselected adult population, increasing with each decade of life to a prevalence of 5.9% in the population older than 65 years. It results in an increased mortality rate and significant morbidity rate related to thromboembolic stroke, loss of atrial systole, and tachycardia-mediated atrial and ventricular cardiomyopathy. 1 Management strategies have been two tiered, either using palliative measures of rate control coupled with anticoagulation or the restoration and maintenance of sinus rhythm. Emerging evidence suggests that the pharmacologic maintenance of sinus rhythm has limited efficacy and value, at least in older patients and in those with persistent AF or structural heart disease. 2 3 4 Consequently, there is heightened interest in the nonpharmacologic, catheter-based approaches to maintain sinus rhythm that may prevent the significant adverse consequences associated with this arrhythmia. This chapter focuses on the current mapping techniques and the advantages and limitations of catheter ablation techniques targeting the triggers and substrate of AF.

Ablation par radiofréquence de la fibrillation auriculaire

Resume La possibilite de guerir les patients souffrant de fibrillation paroxystique au moyen d’un traitement par radiofrequence est un bouleversement dans la prise en charge de cette arythmie. La deconnexion des veines pulmonaires est efficace et sure, passe l’effet d’apprentissage de l’operateur. Cette isolation des veines pulmonaires est l’etape initiale et indispensable permettant l’elimination des fibrillations auriculaires chez 70xa0% des patients. La modification du substrat fibrillatoire grâce aux lesions lineaires augmente le taux de succes a 75xa0% dans les fibrillations chroniques et 82xa0% dans les fibrillations paroxystiques. L’ablation de la fibrillation auriculaire doit etre vue comme un acte chirurgical a cœur ferme isolant des structures et sectionnant des tissus que les progres techniques (nouveaux catheters de radiofrequence) a venir faciliteront probablement. Des etudes comparatives avec le traitement medical evaluent leur efficacite, securite et couts respectifs et pourraient entrainer une augmentation considerable des patients pouvant beneficier de ces gestes curatifs.

Confidence-Based Training for Clinical Data Uncertainty in Image-Based Prediction of Cardiac Ablation Targets

Ventricular radio-frequency ablation (RFA) can have a critical impact on preventing sudden cardiac arrest but is challenging due to a highly complex arrhythmogenic substrate. This work aims to identify local image characteristics capable of predicting the presence of local abnormal ventricular activities (LAVA). This can allow, pre-operatively and non-invasively, to improve and accelerate the procedure. To achieve this, intensity and texture-based local image features are computed and random forests are used for classification. However using machine-learning approaches on such complex multimodal data can prove difficult due to the inherent errors in the training set. In this manuscript we present a detailed analysis of these error sources due in particular to catheter motion and the data fusion process. We derived a principled analysis of confidence impact on classification. Moreover, we demonstrate how formal integration of these uncertainties in the training process improves the algorithm’s performance, opening up possibilities for non-invasive image-based prediction of RFA targets.

Intra-Procedural Techniques: Fluoroscopy and Angiography

X-ray fluoroscopic imaging of the heart is the standard to which all other imaging modalities are currently compared to, and no electrophysiology laboratory is designed without an X-ray system. Even though magnetic resonance (MR) imaging is being used by more laboratories for pre-procedural imaging and is being developed for use as a real-time imaging modality to allow interventional procedures to be carried out within the MR environment, all such systems in use today incorporate an X-ray system (XMR). The pre-eminence of fluoroscopy above imaging modalities is due to a number of factors. Fluoroscopic systems are easy to use, provide real-time information, catheters are easily visualized, electrical interference with recording systems is minimal and virtually no time is required to set up the system.

Early Repolarization Syndrome: Epidemiology, Genetics, and Risk Stratification

Early repolarization (ER) involving the inferolateral leads, previously considered a benign electrocardiographic (ECG) phenomenon, has recently been associated with sudden cardiac death. Although the mechanisms underlying early repolarization are unknown, ER is the latest of the primary electrical cardiac disease discovered to have significantly high prevalence in SCD cases and contribute to increased risk of death from cardioarrhythmic cause. Population-based studies have demonstrated an association between early repolarization and sudden death, primarily when the ECG demonstrates ≥0.2 mV of ST elevation. Risk stratification, especially for asymptomatic patient, remains challenging. However, clinical features as personal history of syncope, familial history of sudden cardiac death and characteristics of the J-wave (>0.2 mV, wide distribution, horizontal/descending ST segment) should be considered at higher risk.

Catheter Ablation of Ventricular Tachycardia and Fibrillation

As in atrial fibrillation (AF), while both triggers and substrate may theoretically be the target of catheter ablation strategies, the presently published literature on catheter ablation of ventricular fibrillation (VF), including isolated case reports, has focused on targeting triggers.1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11The large mass of ventricular myocardium, the importance of maintaining normal mechanical ventricular function, and the risk of creating other forms of malignant arrhythmias mean that ablation strategies aimed at substrate modification are not suitable using the currently available technology. However, previous work in AF has shown that both triggers and substrate may share a close structural relationship. The pulmonary veins play an important role in the initiation and maintenance of AF,12 and recent studies have shed light on their role in the maintenance of AF in some patients. Similarly, several experimental studies demonstrated that Purkinje fibers act as initiators and perpetuators of VF.13,14 Hence, by ablating an area in which the triggering ectopics are found to originate, an additional effect might be substrate modification if the area is implicated in the maintenance of VF.

Anatomical versus electrophysiological approaches for ablation of the slow pathway in patients with AV nodal reentrant tachycardia

Different approaches have been described [1–12] for ablating the slow ‘pathway’ (SP) in patients with atrioventricular nodal reentrant tachycardia (AVNRT). In one approach, electrogram patterns are used to identify the ablation site [1,4], whereas in the other approach, the ablating site is selected on anatomical criteria. Both approaches appear effective, but no study (except one preliminary abstract [8]) comparing the two techniques has been published. In the following study, we analyze the results of these different techniques and investigated the prevalence of electrogram patterns and their relation to a successful outcome in a series of 164 patients.