Duplication or absence of parts of the specialized cardiac conduction system in patients with heterotaxy syndrome causes significant clinical disease, but the mechanistic basis by which embryonic ...

Answer: Enhanced parasympathetic tone and ischemia to the AV nodal artery. Also recall that the right coronary artery (RCA), in addition to supplying the right ventricle and inferior walls, also ...

If the SA node of the heart isn't functioning properly, then this might lead to abnormal rhythms and irregular heartbeat. It is then that you might need a pacemaker. Sometimes the SA node is not able ...

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. When this occurs prior to ...