The conduction system of the heart includes the sinus node, atrioventricular node, atrioventricular bundle, left bundle branch, right bundle branch, and Purkinje fibers. The cardiac conduction system is located within the myocardium and consists of cardiomyocytes capable of generating and conducting conflict. From the sinoatrial node, the heart completes an excitation by conducting to the AV node, then to the AV bundle, to the left and right bundle branches, and finally to the Purkinje fibers. Ischemia and abnormalities at any of the conduction sites can lead to conduction block. If any of the segments agitate prematurely, various arrhythmias can be triggered, such as atrial premature beats, ventricular premature beats, and atrioventricular junctional premature beats. Abnormalities in cardiac conduction can be diagnosed by an electrocardiogram (ECG) and an ambulatory electrocardiogram (EKG). If an ECG reveals an abnormality, it is important to seek medical attention and take medication as prescribed.