Electrical Storms in Brugada Syndrome: Review of Pharmacologic and Ablative Therapeutic Options

Electrical storm occurring in a patient with the Brugada syndrome is an exceptional but malignant and potentially lethal event. Efficient therapeutic solutions should be known and urgently applied because of the inability of usual antiarrhythmic means in preventing multiple recurrences of ventricular arrhythmias. Isoproterenol should be immediately infused while oral quinidine should be further administrated when isoproterenol is not effective. In case of failure of these therapeutic options, ablation of the triggering ventricular ectopies should be attempte

Global and directional activation maps for cardiac mapping in electrophysiology

Abstract Cardiac mapping is a necessary step for accurate diagnostics in cardiology. I

Epicardial Ventricular Tachycardia Ablation for Which Patients?

With the widespread use of implantable cardioverter-defibrillators, an increasing number of patients present with ventricular tachycardia (VT). Large multicentre studies have shown that ablation of VT successfully reduces recurrent VT and this procedure is being performed by an increasing number of centres. However, for a number of reasons, many patients experience VT recurrence after ablation. One important reason for VT recurrence is the presence of an epicardial substrate involved in the VT circuit which is not affected by endocardial ablation. Epicardial access and ablation is now frequently performed either after failed endocardial VT ablation or as first-line treatment in selected patients. This review will focus on the available evidence for identifying VT of epicardial origin, and discuss in which patients an epicardial approach would be benefitial

Electrical storm reversible by isoproterenol infusion in a striking case of early repolarization

A 40-year-old woman was referred to intensive care unit after recurrent ventricular fibrillation. She was free of cardiac medical history or medications. The resting ECG displayed an extended early repolarization in the inferior leads and all the precordial leads. Incessant ventricular fibrillations justified a treatment by intravenous amiodarone associated with general anaesthesia and mechanical ventilation without success on ventricular fibrillation. Because of a low heart rate intravenous isoproterenol infusion was initiated. Isoproterenol infusion was associated with heart rate acceleration and a decrease in J point elevation and the disappearance of ventricular fibrillation episodes. No cardiac disease was documented and the patient was implanted of a single chamber ICD. Six months later the patient was free of syncope and ventricular fibrillation on ICD memory. This case report demonstrates the usefulness and efficiency of the isoproterenol infusion to eliminate recurrent ventricular fibrillation in patients with early repolarization

Endocardial role in arrhythmias induced by acute ventricular stretch and the involvement of Purkinje fibres, in isolated rat hearts

Purkinje fibres (PFs) play an important role in some ventricular arrhythmias and acute ventricular stretch can evoke mechanically-induced arrhythmias. We tested whether PFs and specifically TRPM4 channels, play a role in these mechanically-induced arrhythmias. Pseudo-ECGs and left ventricular (LV) activation, measured by optical mapping, were recorded in isolated, Langendorff-perfused, rat hearts. The LV endocardial surface was irrigated with experimental agents, via an indwelling catheter. The number and period of ectopic activations was measured during LV lumen inflation via an indwelling fluid-filled balloon (100 μL added over 2 s, maintained for 38 s). Mechanically-induced arrhythmias occurred during balloon inflation: they were multifocal, maximal in the first 5 s and ceased within 20 s. Optical mapping revealed activation patterns indicating PF-mediated and ectopic focal sources. Irrigation of the LV lumen with Lugol solution (IK/I2) for 10s reduced ectopics by 93% (n = 16, P < 0.001); with ablation of endocardial PFs confirmed by histology. Five min irrigation of the LV lumen with 50 μM 9-Phenanthrol, a blocker of TRPM4 channels, reduced ectopics by 39% (n = 15, P < 0.01). Immunohistochemistry confirmed that TRPM4 was more abundant in PFs than myocardium. Our results show that the endocardial surface plays an important role in these mechanically-induced ectopic activations. Ectopic activation patterns indicate a participation of PFs in these arrhythmias, with a potential involvement of TRPM4 channels, shown by the reduction of arrhythmias by 9-Phenanthrol

The accessory papillary muscle with inferior J-waves - peculiarity or hidden danger?

Originally described in 1953, today the so-called J-wave is the source of much controversy. As a marker of so-called "early repolarization", this variant has been regarded as a totally benign variant since the 1960's. However, since then a wealth of data have indicated that the J-wave may be a marker of a highly arrhythmogenic substrate with a resultant high risk of sudden cardiac death

New Mathematical approaches in Electrocardiography Imaging inverse problem

International audienceImprove ECGI inverse problem reconstruction Introduce new mathematical approches to the field of the ECGI inverse problem Compare the performance of the new mathematical approaches to the state-of-the-art methods, mainly the MFS method used in commercial devices. In silico validation of the new approches. Assessment of some simplification hypothesis: Torso inhomogeneity Propose some uncertainty quantification apronches to deal with measurements errors Context and objectives Optimal control approach Mathematical model In silico gold standard Results Torso Heterogeneity effect Conclusions Forward model If we know the heart potential we can compute the electrical potential Inverse problem If we know the electrical potential and the current density at the outer boundary of the torso and we look for the electrical potential at the heart surface Computational heart and torso anatomical models + electrodes position Computational torso meshes: 250 nodes mesh (blue). More accurate FE mesh with 6400 nodes (green) Remarks Introducing the torso heterogeneity is natural with FEM. also anisotropy could be introduced The error is more important in the left ventricle Main results and perspectives New mathematical approches for solving the inverse problem in electrocardiography imaging based on optimal control Over all the 20 cases used in this study the optimal control method performs better than the MFS both in terms of relative error and correlation coefficient: Acknowledgment: This work was partially supported by an ANR grant part of "Investissements d'Avenir" program with reference ANR-10-IAHU-04. It is also supported by the LIRIMA international lab thought the EPICARD tea