Sick sinus syndrome and atrial fibrillation in older persons — A view from the sinoatrial nodal myocyte. (June 2015)

• Record Type: Journal Article
• Authors: Monfredi, O.; Boyett, M.R.
• Is Part Of: Journal of molecular and cellular cardiology. Volume 83(2015:Jun.)
• Page Start: 88
• Page End: 100
• Publication Date: 2015-06
• Subjects: Sinoatrial node -- Pacemaking -- Ion channels -- Calcium handling -- Atrial fibrillation -- Arrhythmia; Cardiology -- Periodicals; Heart Diseases -- Periodicals; Molecular Biology -- Periodicals; Cardiologie -- Périodiques; Cardiology; Electronic journals; Periodicals; 616.12
• DOI: 10.1016/j.yjmcc.2015.02.003
• Languages: English
• ISSNs: 0022-2828

Abstract

Abstract: Sick sinus syndrome remains a highly relevant clinical entity, being responsible for the implantation of the majority of electronic pacemakers worldwide. It is an infinitely more complex disease than it was believed when first described in the mid part of the 20th century. It not only involves the innate leading pacemaker region of the heart, the sinoatrial node, but also the atrial myocardium, predisposing to atrial tachydysrhythmias. It remains controversial as to whether the dysfunction of the sinoatrial node directly causes the dysfunction of the atrial myocardium, or vice versa, or indeed whether these two aspects of the condition arise through some related underlying pathological mechanism, such as extracellular matrix remodeling, i.e., fibrosis. This review aims to shed new light on the myriad possible contributing factors in the development of sick sinus syndrome, with a particular focus on the sinoatrial nodal myocyte. This article is part of a Special Issue entitled CV Aging. Graphical abstract: Highlights: Sick sinus syndrome (SSS) remains an extremely important clinical problem. It is responsible for more electronic pacemaker insertions than any other arrhythmia. SSS is a complex syndrome of symptomatic bradycardia interspersed with tachycardia. SSS may occur as a consequence of myriad diverse electrophysiological alterations. These changes occur in both the sinus node and the atrial myocardium.