Your heart’s job is to keep your pulse steady to pump blood throughout your body. Sometimes your heart rate is slower when you’re relaxing, and sometimes it’s faster when you’re exercising or stressed ...

Bradycardia is a condition characterized by a slower than normal heart rate. While a normal adult heart beats between 60 and ...

An accelerated junctional rhythm occurs when the heart’s atrioventricular node beats too quickly. Damage to the heart’s primary natural pacemaker causes it.

When you have a wandering atrial pacemaker, control of your heartbeat shifts from your SA node to other parts of your atria, the two upper chambers of your heart. When that happens and your heart ...

Sick sinus syndrome (SSS) is a group of heart rhythm problems that occur when the heart's natural pacemaker—the sinoatrial (SA) node, also known as the sinus node—doesn't function properly.

Normal heart rate The heart has a complex system of nerves that conduct the electrical impulses fired by the sino-atrial node (SA node) and spread them throughout the heart, causing it to pump.

Atrial tachycardia (AT). Your sinoatrial (SA) node is the only place that can create a new electrical impulse to cause a heartbeat. But if you have AT, an extra area in your atria is sparking ...

The SA node is composed of specialised pacemaker cells, which send out an electrical impulse throughout the cardiomyocytes (cardiac cells), ensuring the heart beats properly.

During an average lifetime, the heart beats more than 2 billion times. To you, it might just be a steady "lub-dub" that speeds up under pressure and slows as you drift to sleep. But behind that ...

A premature atrial contraction (PAC) occurs when a focus in the atrium (not the SA node), generates an action potential before the next scheduled SA node action potential. There are four main ...