PPT-ANTIDYSRHYTHMICS ECG Contraction of atria

Contraction of ventricles Repolarization of ventricles Cardiac Arrhythmias result from disorders of impulse formation conduction or both Causes of arrhythmias Cardiac ischemia Excessive discharge or sensitivity to autonomic transmitters. Review Principles of Muscle Mechanics. Same principles apply to contraction of a single fiber and a whole muscle. Contraction produces tension, the force exerted on the load or object to be moved. Review Principles of Muscle Mechanics. Physiology . of the Heart. Mechanism and Events of Contraction. 1) Influx of sodium ions from the extracellular fluid into the cells initiates the action potential by opening voltage-regulated sodium channels . Refers to the events of 1 complete heart beat . Both atria & ventricles contract then relax (0.8 sec if beating 75x/min). Key terms to know. Diastole. - relaxation. Systole. - contraction. Lub-dub. Rhythm refers to the regularity . or spacing . of the ECG waves. Any variation from the . normal rhythm . and sequence of excitation of the heart is termed . an arrhythmia.. Or simply. Abnormal rhythm of heart is called arrhythmia.. Circuits of the Blood. There are 3 circuits:. Systemic Circulation. From the left ventricle to the aorta and on to the body. Back to the heart via the superior and inferior vena cava to the right atrium. Heart – located in mediastinum within the thoracic cavity. The Pericardium – . membrane surrounding heart. Serous Pericardium . = 1. Parietal - outer layer. 2. Visceral - inner layer (part of . epicardium. The Pericardium – . membrane surrounding heart. Serous Pericardium . = 1. Parietal - outer layer. 2. Visceral - inner layer (part of . epicardium. ). Layers of Heart Wall. Epicardium. – outermost layer. Heart Wall. Three layers. Epicardium. Outside layer. AKA visceral pericardium. Pericardium. Visceral pericardium or epicardium. Next to heart. Actually part of heart wall. Parietal pericardium. Outside layer. ASSIGNMENT. : Most Of The Anatomy We Have Already Done In The Lab, So Make Sure To Do The . * of slide 1 through 29. . As I Will Likely Not Take The Time To Review This Material.. *. PARTS OF THE CARDIOVASCULAR SYSTEM. DHO 7.8 pg. 186. HS1/2016-2017. Electrical impulses in the heart cause its cyclic contractions. Conductive pathway includes:. SA node. AV node. Bundle of His. Asst. Prof. Dr. . Ghaith Ali Jasim Al . Zubaidy. PhD Pharmacology. MSc. Physiology & Pharmacology. dr.ghaithali@yahoo.com. Cardiovascular System Function. Functional components of the cardiovascular system:. October . 24 - 25 2017. Muscle . Structure. Muscle. Fascicle (bundle of fibers). Muscle . Fiber (single cell). Myofibril (organelle). Sarcomere (unit of contraction). Microscopic Anatomy of Skeletal Muscle. CIRCULATORY SYSTEM. (BLOOD VESSELS). Cardiovascular system. Heart. Single function. Pump blood through blood vessels. Circulatory system. Blood and lymph vessels. Services tissue needs for . Oxygen. Nutrients. ANATOMY. The heart acts as two serial pumps that share several electrical and mechanical components. . The right heart circulates blood to the lungs where it is oxygenated, and the left heart receives this and circulates it to the rest of the body..