It's our body's natural pacemaker, and it uses electrical signals to set the pace (see What determines the rhythm of your heart?)

The natural pacemaker (the SA node) loses some of its cells.

Within the right atrium of a normal heart is a natural pacemaker that initiates and controls the heartbeat.

Had he suffered a heart attack that affected the natural pacemaker in his heart?

The heart contains a cluster of specialized muscle cells that act as the heart's natural pacemaker.

The SA node is sometimes called the "natural pacemaker" of the heart.

It means that the heart's natural pacemaker is not working right or that the electrical pathways of the heart are disrupted.

This node is your heart's natural pacemaker.

It can occur when the heart's natural pacemaker is damaged.

An implanted electrical device that replaces the heart's natural pacemaker.