title: Ventricular arrhythmias and the His-Purkinje system.
abstract: Ventricular arrhythmias are a major cause of sudden death, which accounts for approximately half of cardiac mortality. The His-Purkinje system is composed of specialized cells responsible for the synchronous activation of the ventricles. However, experimental studies show that the Purkinje system can be arrhythmogenic during electrolyte imbalance, after exposure to various drugs, and in myocardial ischaemia, during which Purkinje cells can survive in anaerobic conditions. Purkinje cells can generate both automatic and triggered focal rhythms, and their network configuration can accommodate re-entrant circuits. In humans, a variety of monomorphic ventricular tachycardias can be sustained within the architecture of the Purkinje branches. Furthermore, discrete Purkinje sources can serve as critical triggers of ventricular fibrillation in a wide spectrum of patients with structural heart disease or with an apparently normal heart. In drug-resistant cases of monomorphic and polymorphic Purkinje-related ventricular tachycardias, catheter ablation is a very effective treatment. The specific transcriptional signatures and functional properties of Purkinje cells, including their intracellular calcium dynamics, underlie their extreme arrhythmogenicity. However, the identification of vulnerable individuals remains challenging, and the molecular mechanisms of Purkinje-related arrhythmias have to be characterized further to enable the development of interventions to prevent lethal cardiac arrhythmias.
authors.affiliation: Hôpital Cardiologique du Haut Lévêque, Avenue de Magellan, 33604 Pessac Cedex, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Haissaguerre
authors.affiliation: IHU LIRYC, Site Xavier Arnozan, Avenue du Haut Lévêque, 33600 Pessac, France.
authors.forename: Edward
authors.initials: E
authors.lastname: Vigmond
authors.affiliation: IHU LIRYC, Site Xavier Arnozan, Avenue du Haut Lévêque, 33600 Pessac, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Stuyvers
authors.affiliation: Hôpital Cardiologique du Haut Lévêque, Avenue de Magellan, 33604 Pessac Cedex, France.
authors.forename: Meleze
authors.initials: M
authors.lastname: Hocini
authors.affiliation: IHU LIRYC, Site Xavier Arnozan, Avenue du Haut Lévêque, 33600 Pessac, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Bernus
mesh_terms: D000200:Action Potentials; D000818:Animals; D002036:Bundle of His / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D011690:Purkinje Fibers / Q000503:physiopathology*; D018570:Risk Assessment; D012307:Risk Factors; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy