© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Chapter 13 Heart

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Functions of the Circulatory System The heart is the pump that circulates blood to all parts of the body Arteries, veins, and capillaries transport the blood Blood carries oxygen and nutrients to the cells and carries waste products away Lymph system returns excess fluid from the tissues the circulation

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Major Blood Circuits Blood leaves the heart through arteries and returns by veins Blood circulation routes –General or system circulation –Cardiopulmonary circulation Changes in the composition of circulating blood

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. The Heart About 5 inches long and 3.5 inches wide Weighs about 1 pound Located in the thoracic cavity; the apex of the heart lies on the diaphragm and points to the left of the body

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Figure 13-1 The heart is located in the thoracic cavity between the lungs

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. The Heart After 4 to 5 minutes without blood flow, brain cells are irreversibly damaged Can hear the heartbeat through a stethoscope Cardiac arrest Cardiopulmonary resuscitation (CPR)

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Structure of the Heart (1 of 2) Hollow, muscular, double pump Pericardium and pericardial fluid Epicardium Myocardium –Cardiac muscle tissue Endocardium

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Structure of the Heart (2 of 2) Superior and inferior vena cava Coronary sinus Pulmonary artery Pulmonary veins Aorta

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Figure 13-2 Anterior external view of the heart

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Figure 13-3 Anterior cross-sectional view of the heart

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Chambers and Valves (1 of 2) Separated into right and left halves by the septum; then each half separated into an upper and lower chamber Upper chambers –Left and right atria

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Chambers and Valves (2 of 2) Lower chambers –Left and right ventricles Valves keep blood flowing in one direction

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Valves Atrioventricular valves –Tricuspid valve (separates the right atria and right ventricle) –Bicuspid or mitral valve (separates the left atria and left ventricle) Semilunar valves –Pulmonary semilunar valve (opening of the pulmonary arteries) –Aortic semilunar valve (opening of the aorta)

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Physiology of the Heart Double pump Right heart –Deoxygenated blood Left heart –Oxygenated blood

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Heart Rate and Cardiac Output Normal adult rate is between 72 and 80 beats per minute Cardiac output=stroke volume x heart rate Calculating the cardiac output Exercise increases cardiac output

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Heart Sounds Valves make sounds when they close Called lubb dupp sounds Lubb –Tricuspid and bicuspid valves (S1) Dupp –Aortic and pulmonary valves (S2)

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Conduction System Electrical impulses cause rhythmic beating of the heart Sinoatrial (SA) node or pacemaker Atrioventricular (AV) node Bundle of His Purkinje fibers

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Figure 13-7 An electrical impulse from the SA node travels to the AV node and causes the ventricle to contract

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. ECG or EKG (1 of 2) The electrocardiogram is a device to record the electrical activity of the heart Systole –Contraction Diastole –Relaxation

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. ECG or EKG (2 of 2) Positive and negative deflection P, QRS, and T waves

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Effects of Aging Heart muscle fibers replaced by fibrous tissue Heart valves increase in thickness Cardiac output decreases Changes become more significant when elderly person becomes physically or mentally stressed

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Prevention of Heart Disease Heart disease is the leading cause of death for both men and women in the US –Coronary heart disease Risk factors Steps to lower risk or prevent heart disease Blood cholesterol levels and triglycerides

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Diagnostic Tests – Noninvasive (1 of 2) Angiography Cardiac MRI Coronary calcium scoring/heart scan Echocardiography Electrocardiogram

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Diagnostic Tests – Noninvasive (2 of 2) Exercise stress tests Holter monitor MUGA (multiple gated acquisition scan) Nuclear perfusion

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Diagnostic Tests – Invasive Cardiac catheterization IVUS (intravascular coronary ultrasound) TEE

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Diagnostic Tests – Blood Tests Arterial blood gases BNP Lipid panel C-reactive protein Cardiac Troponin T

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Diseases of the Heart – Common Symptoms Arrhythmia Bradycardia Tachycardia Murmurs Mitral valve prolapse

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Diseases of the Coronary Artery Coronary artery disease (CAD) Angina pectoris Myocardial infarction

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Infectious Diseases of the Heart Pericarditis Myocarditis Endocarditis Rheumatic heart disease

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Heart Failure (1 of 2) When the ventricles of the heart are unable to contract effectively and blood pools in the heart Symptoms depend on which ventricle fails

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Heart Failure (2 of 2) Left ventricle failure –Dyspnea (shortness of breath) Right ventricle failure –Engorgement of organs, edema of the legs and feet, and ascites

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Congestive Heart Failure Similar to heart failure Left-sided failure – pulmonary edema Right-sided failure – fluid buildup throughout body Treatment

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Rhythm/Conduction Defects Heart block –First-degree block –Second-degree block –Third-degree block or complete heart block Premature contractions –Atrial fibrillation –PVCs –Ventricular fibrillation

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Types of Heart Surgery Angioplasty Cardiac stents Coronary bypass Transmyocardial laser revascularization

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Heart Transplants Used as a last resort Histocompatibility Organ rejection

© 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Medical Highlights Pacemaker Cardiac resynchronization therapy Defibrillator Heart pumps