[Cardiac conduction disorders in the elderly].

While the left bundle branch block frequently reflects underlying cardiac disease, conductive disorders occurring at three levels (sinus node, atrioventricular node, and branches of the bundle of His), are usually part of the aging heart. In addition, AV nodal block and sinus node dysfunction are readily compounded with drugs, often indispensable (beta-blockers, calcium-blockers, digoxin, antiarrhythmic), and very common among the elderly. Indications for permanent pacing are accurately described and come in four classes: I, recommended (mandatory) - IIa, raisonable - IIb, possible - III, contraindicated. In 2009, 24H ECG Holter and electrophysiological study are generally disappointing in the positive diagnosis of syncope, so the clinical characteristics of syncope are essential in the decision of device implantation. Indeed, in the absence of ECG recorded at the time of the syncope, the diagnosis of BAV or BSA cannot be certain, and on the contrary, vague symptoms should not be attributed to a patent bradycardia of sinus or AV block origin without any precaution. Finally, the relationship between sinus dysfunction and carotid sinus syndrome remain poorly understood, dysautonomia is common among the elderly, and the existence of conduction disorders associated with syndrome of sleep apnea should not be ignored.