![]() ![]() The left bundle splits further into the left anterior fascicle and left posterior fascicle. The left bundle branch activates the left ventricle, whilst the right bundle activates the right ventricle. ![]() The distal part of the AV node is called the Bundle of His which splits into two bundle branches in the inter ventricular septum (left and right). The AV node introduces a critical delay (the PR interval) into the conduction system allowing blood to flow from the atria into the ventricles. The impulse is propagated from the right atrium to the left atrium via Bachmann’s bundle.Ĭonduction to the AV node occurs in specialised tissue called intermodal tracts. Normally, electrical activity is spontaneously generated by the SA node (the ‘physiological pacemaker’) Signals arising from the SA node stimulate the atria to contract and are conducted to the AV node (the P wave on the ECG). The conduction pathways of the heart consist of: A final section describes drug therapy and pacing in more detail.įigure 1: The conduction pathways of the heart. The causes, clinical presentations and management for each type of bradycardia are discussed in more detail in the sections below. May be asymptomatic worsening of angina pectoris or heart failure. Other symptoms may relate to the underlying cause. Organophosphates (including nerve agents)īradycardia may present as an incidental finding or with symptoms related to hypotension: Various drugs can also affect the electrophysiology of the heart myocytes and their nerve supply (Table 1). Electrolyte disturbance: Hyperkalaemia and hypokalaemia.Normal physiological variants as seen, for example, in athletes. ![]() The causes of bradycardia can be broadly categorised as: Bradycardia is defined as a heart rate of less than 60 beats per minute. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |