Cardiovascular Physiology PDF

Cardiovascular Physiology Chapter 18 I. Heart General Information A. Pump Systems 1. Pulmonary 2. Systemic I. Heart General Information A. Pump Systems 1. Pulmonary 2. Systemic B. Location 1. Mediastinum 2. Pericardial Cavity C. Structure 1. External Structure a. Apex b. Base I. Heart General Inform...

Cardiovascular Physiology Chapter 18 I. Heart General Information A. Pump Systems 1. Pulmonary 2. Systemic I. Heart General Information A. Pump Systems 1. Pulmonary 2. Systemic B. Location 1. Mediastinum 2. Pericardial Cavity C. Structure 1. External Structure a. Apex b. Base I. Heart General Information C. Structure 1. External Structure 2. Chambers a. b. Atria Ventricles 3. Valves a. b. c. d. Bicuspid Tricuspid Aortic Semilunar Pulmonary Semilunar 4. Chordae tendonae 5. Papillary muscles I. Heart General Information D. Coverings 1. Fibrous Pericardium 2. Serous Pericardium a. b. Parietal layer Visceral layer E. Layers 1. Endocardium 2. Myocardium 3. Epicardium Functions Transportation! Gases (O2 and CO2) Nutrients/wastes Proteins (i.e. clotting) Communication Hormones Proteins Body Temperature II. Blood Flow A. Pulmonary B. Systemic C. Coronary Coronary Blood Flow C. Coronary Circulation 1. Left coronary artery a. Anterior interventricular artery b. Circumflex artery 2. Right coronary artery a. Right marginal artery b. Posterior interventricular artery C. Coronary Circulation 3. Coronary Veins a. Cardiac veins 1.) Great cardiac vein 2.) Middle cardiac vein 3.) Small cardiac vein b. Coronary Sinus c. Anterior cardiac veins 4. Angina pectoris 5. Myocardial Infarction III. Cardiac Muscle Cells A. Characteristics of cardiac myocytes 1. Branched 2. Striated 3. Intercalated discs B. Physiology 1. Cardiac myocytes - contractile 2. Pacemaker cells – spontaneously depolarize a. Autorhythmicity b. No neural input III. Cardiac Muscle Cells 3. Sarcoplasmic reticulum a. Stores calcium b. Extracellular calcium triggers the release of calcium from the SR c. Slow calcium channels allow for the entry of 10-20% of extracellular calcium d. 80-90% calcium comes from the SR 2. 1. 3. Cardiac Cycle Atrial depolarization Conduction through AV node and AV bundle Ventricles relax Ventricular repolarization Ventricular Contraction Ventricular contraction Electrocardiogram Waves Segments Abnormal EKGs U wave IV. Cardiac Rhythm A. Intrinsic Conduction System 1. Noncontractile cardiac Cells a. b. c. Autorhythmic About 1% of the cardiac fibers Unstable resting potential 2. Action Potentials a. Pacemaker potential b. Depolarization c. Repolarization 3. Defects a. Arrhythmias b. Fibrillation IV. Cardiac Rhythm A. Intrinsic Conduction System 4. Sequence of excitation a. b. c. d. e. SA node AV node AV bundle Right and left bundle branches Subendocardial conducting network IV. Cardiac Rhythm B. Extrinsic Innervation of the Heart 1. Nerves of the heart a. Medulla oblongata b. Cardioaccelerator center c. Cardioinhibitory center IV. Cardiac Rhythm B. Extrinsic Innervation of the Heart 2. Action Potential of Contractile Cardiac Cells a. Depolarization b. Plateau Phase c. Repolarization C. Cardiac Cycle 1. Systole 2. Diastole 3. Phases of the Cardiac cycle a. ventricular filling b. Isovolumetric contraction c. Ventricular ejection d. Isovolumetric ventricular relaxation Phases of the Cardiac Cycle – Wiggers Diagram End Diastolic Volume End Systolic Volume Stroke Volume EDV-ESV = SV Atrial Ventricular Systole Ventricular Cardiac Output CO = HR X SV Factors affecting Stroke Volume 1. Length of muscle fibers Preload Frank-Starling Law of the heart 2. Contractility Increased contractility Decreased contractility Factors affecting stroke volume Heart Rate Parasympathetic Control Acetylcholine K+ channels increase permeability Ca2+ permeability decreases Sympathetic Control Catecholamines (NE & Epi) β1- adrenergic receptors Increased permeability to Na+ and Ca2+ V. Embryology of the heart A. Endocardial tubes B. 4 chambers form 1. 2. 3. 4. Sinus venosus Atrium Ventricle Bulbis cordis C. Fetal heart adaptations 1. Umbilical arteries and vein 2. Foramen Ovale 3. Ductus Arteriosus VI. Clinical Heart Problems A. Heart Rate 1. Tachycardia 2. Bradycardia B. Cardiac Output 1. 2. 3. 4. 5. Congestive Heart Failure Coronary atherosclerosis High Blood Pressure Multiple myocardial infarctions Dilated cardiomyopathy Compliance Draw a concept map for Cardiac Output