Pharmacologic Approach to Sinoatrial Node Dysfunction.

The spontaneous activity of the sinoatrial node initiates the heartbeat. Sinoatrial node dysfunction (SND) and sick sinoatrial syndrome are caused by the heart's inability to generate a normal sinoatrial node action potential. In clinical practice, SND is generally considered an age-related pathology, secondary to degenerative fibrosis of the heart pacemaker tissue. However, other forms of SND exist, including idiopathic primary SND, which is genetic, and forms that are secondary to cardiovascular or systemic disease. The incidence of SND in the general population is expected to increase over the next half century, boosting the need to implant electronic pacemakers. During the last two decades, our knowledge of sinoatrial node physiology and of the pathophysiological mechanisms underlying SND has advanced considerably. This review summarizes the current knowledge about SND mechanisms and discusses the possibility of introducing new pharmacologic therapies for treating SND. Expected final online publication date for the Annual Review of Pharmacology and Toxicology, Volume 61 is January 7, 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.