Unit 6. Terms related to ECG and Arrhythmiasis.pdf

Terms related to ECG and Arrhythmias AWAD MOHAMMED ALQAHTANI BSc of Anesthesia Technology King Khalid University, Muhayil Asir  Electrocardiography (ECG) Process of recording electrical activity of heart Able to diagnose arrhythmias, myocardial damage,...

Terms related to ECG and Arrhythmias AWAD MOHAMMED ALQAHTANI BSc of Anesthesia Technology King Khalid University, Muhayil Asir  Electrocardiography (ECG) Process of recording electrical activity of heart Able to diagnose arrhythmias, myocardial damage, and heart problems Because a large number of cells in the heart rhythmically depolarize, with each contraction, we can record the electrical changes on our body surface.  Basic Heart Anatomy Heart consists of 4 chambers (2 atria & 2 ventricles). Atria are smaller than ventricles, left ventricle bigger than right ventricle. Blood flows in the following order: 1. Right atria 2. Right ventricle 3. Lungs 4. Left atria 5. Left ventricle 6. Rest of Body  Conduction System 1-SA Node (Pacemaker) 2-AV Node 3-Bundle of His 4-Perkinje fibers  Electrocardiogram and Heart Rate 1. The SA-node is the first part of the heart to show Heart electrical activity. ECG  Electrocardiogram and Heart Rate 2. Shortly after the SA-node fires, both atria of the heart depolarize (P-wave) followed closely by atrial contraction. Heart ECG  Electrocardiogram and Heart Rate 3. There is a brief pause, and then the AV-node, Bundle of HIS, and Purkinje fibers fire in succession Heart (QRS complex). ECG  Electrocardiogram and Heart Rate 3. There is a brief pause, and then the AV-node, Bundle of Heart HIS, and Purkinje fibers fire in succession (QRS complex). ECG  Electrocardiogram and Heart Rate 3. There is a brief pause, and then the AV-node, Bundle of HIS, and Purkinje fibers fire in succession Heart (QRS complex). ECG  Electrocardiogram and Heart Rate 3. There is a brief pause, and then the AV-node, Bundle of HIS, and Purkinje fibers fire in succession Heart (QRS complex). ECG  Electrocardiogram and Heart Rate 4. Following Ventricular depolarization, the ventricles Heart contract and repolarization (T-wave) occurs. ECG  Contraction of ventricles ECG (EKG) showing wave segments Repolarization of Contraction of atria ventricles  Normal heartbeat and atrial arrhythmia Normal rhythm Atrial arrhythmia AV septum  Arrhythmias Result from disorders of impulse formation, conduction, or both. Palpitation Fibrillation Atrial fibrillation Ventricular fibrillation Bradycardia Tachycardia  Mechanism of Arrhthmogensis 1. Disorder of impulse formation. a) Automaticity. b) Triggered Activity. 1) Early after depolarization. 2) Delayed after depolarization. 2. Disorder of impulse conduction. a) Block – Reentry. b) Reflection. 3. Combined disorder.  Common Arrhythmias SINUS TACHYCARDIA (Rate: 101-160/min) SINUS BRADYCARDIA (Rate: 40-59 bpm) MULTIFOCAL ATRIAL TACHYCARDIA (Rate: 100-250/bpm) PAROXYSMAL ATRIAL TACHYCARDIA (Atrial rate: 160-250/min) ATRIAL FIBRILLATION (Atrial rate : 400-650/bpm) VENTRICULAR TACHYCARDIA (Rate: 100 to 220/bpm) VENTRICULAR FIBRILLATION(Ventricules rate : 150 to 500/bpm)  References Quick and Easy Medical Terminology, 7th Edition, Peggy C. Leonard, Elsevier, 2014. Page Number: 171-197.