Familial primary arrhythmias: Genes, mechanisms and treatment: Present perspective

The Heart is a specialised organ that contracts synchronously, pumping blood to the body and to the lungs. The upper two chambers of the heart are called atria (right and left), the bottom two chambers are called ventricles (right and left). Right atrium receives deoxygenated blood from all parts of the body except for the lungs and transports them to right ventricle. The left atrium receives oxygenated blood from the lungs and transports them to the left ventricle and then to rest of the body. Cardiac excitation originates in the sinoatrial (SA) node and propagates through the atria into the atrial-ventricular (AV) node. The impulse then propagates through the Purkinje conduction system to the ventricles which then contract. The synchronized pumping action of the heart is caused by a flow of electricity through the heart that repeats itself in a cycle.