The normal sinus node: What we know now
Abstract
The sinus node is the physiological pacemaker of the heart. Different pathophysiological conditions lead to a reduction of its function, which is clinically called sinus dysfunction. However, for a better understanding of its disease state, it is necessary to elucidate how it works under normal conditions. New evidences indicate that the automatism of the sinus node is produced by the interaction of the membrane clock and the calcium clock, which gives it a strong character that protects it against malfunctions. Current evidences on cell synchrony within the sinus node are presented, as well as the form of electrical propagation and the source-sink coupling. In addition, recent anatomical and histological findings are described.Downloads
References
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