Chapter 13 Heart

Draw the Pathway of Blood Flow

AGAIN… Draw, Color & Label 

Media Time  https://www.youtube.com/watch?v=5tUWOF6wEnk

Functions of the Circulatory System The heart is the pump that circulates blood Arteries, veins, and capillaries transport the blood Blood carries oxygen and nutrients to the cells and carries waste products away Lymph system functions

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

The Heart About the size of a closed fist 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

The Heart © 2014 Cengage Learning.

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)

Structure of the Heart Hollow, muscular, double pump Pericardium and pericardial fluid Myocardium Cardiac muscle tissue Endocardium Superior and inferior vena cava Coronary sinus Pulmonary artery Pulmonary veins Aorta

Structure of the Heart © 2014 Cengage Learning.

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Chambers and Valves 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 Lower chambers Left and right ventricles Valves keep blood flowing in one direction

Valves Atrioventricular valves Semilunar valves Tricuspid valve Bicuspid or mitral valve Semilunar valves Pulmonary semilunar valve Aortic semilunar valve

Physiology of the Heart Double pump Right heart Deoxygenated blood POOR BLOOD Left heart Oxygenated blood RICH BLOOD

Heart Rate and Cardiac Output Normal adult rate is between 72 and 80 beats per minute (60 to 100 beats a minute) Stroke volume is the amount of blood ejected by the left ventricle in one contraction. Although stroke volume can refer to either left or right side of the heart, it is most associated with the left side. Calculating the cardiac output Cardiac output is the volume of blood pumped by the heart per minute (mL blood/min). Cardiac output is a function of heart rate and stroke volume. The heart rate is simply the number of heart beats per minute. The stroke volume is the volume of blood, in milliliters (mL), pumped out of the heart with each beat. Exercise increases cardiac output

Heart Sounds Valves make sounds when they close Called lubb dupp sounds Lubb Tricuspid and bicuspid valves (S1) Dupp Aortic and pulmonary valves (S2)

Conduction System Electrical impulses cause rhythmic beating of the heart Sinoatrial (SA) node or pacemaker Atrioventricular (AV) node Bundle of His Purkinje fibers https://www.youtube.com/watch?v=fZT9vlbL2uA

The heartbeat happens as follows: The SA node (called the pacemaker of the heart) sends out an electrical impulse. The upper heart chambers (atria) contract. The AV node sends an impulse into the ventricles. The lower heart chambers (ventricles) contract or pump.

Conduction System © 2014 Cengage Learning.

ECG or EKG The electrocardiogram is a device to record the electrical activity of the heart Systole Contraction Diastole Relaxation

ECG or EKG Positive and negative deflection (change direction) P, QRS, and T waves Being able to interpretate these details allows diagnosis of a wide range of heart problems. https://www.youtube.com/watch?v=RYZ4daFwMa8

Prevention of Heart Disease Heart disease is the leading cause of death Coronary heart disease Risk factors High blood cholesterol and triglyceride levels (a type of fat found in the blood) High blood pressure Diabetes and prediabetes Overweight and obesity Smoking Lack of physical activity Unhealthy diet Stress The risk factors you can't control are age, gender, and family history

Steps to lower risk or prevent heart disease Eat healthy Exercise Blood cholesterol levels and triglycerides

Diagnostic Tests – Noninvasive Angiography visualize the inside of blood vessels and organs of the body, with particular interest in the arteries, veins, and the heart chambers

Coronary calcium scoring/heart scan Cardiac MRI Cardiac MRI is a common test. It's used to diagnose and assess many diseases and conditions, including: Coronary heart disease. Damage caused by a heart attack. Heart failure. Coronary calcium scoring/heart scan Cardiac calcium scoring uses a special X-ray called a computed tomography (CT) scan to find the buildup of calcium on the walls of the arteries

Dx: fibrillation Echocardiography Electrocardiogram Echocardiography uses standard two-dimensional, three-dimensional, and Doppler ultrasound to create images of the heart. Electrocardiogram Echocardiogram, often referred to as a cardiac echo or simply an echo, is a sonogram of the heart. (ECG is an abbreviation for an electrocardiogram.) Dx: fibrillation

Electrocardiogram to DX Fibrillation - a muscular twitching, very rapid irregular contractions of the muscle fibers of the heart atrial fibrillation, ventricular fibrillation Electrocardiogram to DX

Diagnostic Tests – Noninvasive Exercise stress tests A stress test, sometimes called a treadmill test or exercise test, helps a doctor find out how well your heart handles work. As your body works harder during the test, it requires more oxygen, so the heart must pump more blood. The test can show if the blood supply is reduced in the arteries that supply the heart.

MUGA (multiple gated acquisition scan) Holter monitor A Holter monitor is a continuous tape recording of a patient's EKG for 24 hours. Since it can be worn during the patient's regular daily activities, it helps the physician correlate symptoms of dizziness, palpitations (a sensation of fast or irregular heart rhythm) or black outs. MUGA (multiple gated acquisition scan) highly accurate test used to determine the heart's pumping function, nuclear imaging test.

Diagnostic Tests – Invasive Cardiac catheterization Cardiac catheterization (cardiac cath or heart cath) is a procedure to examine how well your heart is working. A thin, hollow tube called a catheter is inserted into a large blood vessel that leads to your heart.

IVUS (intravascular coronary ultrasound) test that uses sound waves to see inside blood vessels. It is useful for evaluating the coronary arteries that supply the heart.

Diagnostic Tests – Blood Tests Arterial blood gases measures the amounts of certain gases (such as oxygen and carbon dioxide) dissolved in arterial blood. An ABG test involves puncturing an artery with a thin needle and syringe and drawing a small volume of blood. BNP a substance secreted from the ventricles or lower chambers of the heart in response to changes in pressure that occur when heart failure develops and worsens. The level of BNP in the blood increases when heart failure symptoms worsen, and decreases when the heart failure condition is stable.

Lipid panel C-reactive protein Lipids include cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglycerides. The basic lipid panel measures total cholesterol, triglyceride levels, HDL and LDL cholesterol. C-reactive protein produced by the liver. The level of CRP rises when there is inflammation throughout the body. It is one of a group of proteins called "acute phase reactants" that go up in response to inflammation

Cardiac Troponin T indicators of damage to the heart muscle (myocardium). They are measured in the blood to differentiate between unstable angina and myocardial infarction (heart attack) in people with chest pain.

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

Diseases of the Heart – Common Symptoms Arrhythmia-change from normal rate/rhythm Bradycardia-slow/heart beats less then 60 beats/min Tachycardia- fast/heart beast more then 100 beats/min Murmurs- valve fails to close properly (hissing sound or gurgling sound) surg to replace if necessary Mitral valve prolapse- between LA & LV closes imperfectly (s/s: fatigue, palpitations, HA, Chest Pain, Anxiety)

Diseases of the Coronary Artery Coronary artery disease (CAD)- narrowing of the arteries, plaque builds up and causes Heart Attack Angina pectoris- Chest Pain (Call 911, lie down, ASA, Nitro to open artery) Myocardial infarction- MI/Heart Attack (s/s: chest pain, nausea, sweating, fatigue, dyspnea/difficulty breathing) DAMAGE HEART MUSCLE CANT PUMP BLOOD.

Infectious Diseases of the Heart Pericarditis- Inflammation outer member covering of heart Myocarditis- Inflammation of heart muscle Endocarditis- Inflammation membrane that lines heart valves & heart CAN lead to Fatal BLOOD CLOT) Rheumatic heart disease- result from frequent strep throat, attack lining of heart

Heart Failure When the ventricles of the heart are unable to contract effectively and blood pools in the heart Symptoms depend on which ventricle fails LEFT Ventricle=S/S: Dyspnea occurs RIGHT Ventricle=Organ fill with blood, S/S: edema, lung congestion, coughing

Heart Failure Left ventricle failure Right ventricle failure Dyspnea Engorgement of organs, edema, and ascites(serous fluid in abd cavity)

Congestive Heart Failure Similar to heart failure Left-sided failure pulmonary edema Right-sided failure fluid buildup throughout body Treatment medication & diuretics

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

Types of Heart Surgery Angioplasty Cardiac stents surgical repair or unblocking of a blood vessel, especially a coronary artery. https://www.youtube.com/watch?v=e13TGGccvT4 Cardiac stents a tube-shaped device placed in the coronary arteries that supply blood to the heart, to keep the arteries open in the treatment of coronary heart disease https://www.youtube.com/watch?v=1aJ60DTnT2k

Transmyocardial laser revascularization Coronary bypass During coronary artery bypass graft surgery (also called CABG), a blood vessel is removed or redirected from one area of the body and placed around the area or areas of narrowing to "bypass" the blockages and restore blood flow to the heart muscle. This vessel is called a graft. https://www.youtube.com/watch?v=7ZuU0uzRCDU Transmyocardial laser revascularization a new treatment aimed at improving blood flow to areas of the heart that were not treated by angioplasty or surgery. A special carbon dioxide (CO2) laser is used to create small channels in the heart muscle, improving blood flow to the heart muscle.

Heart Transplants Used as a last resort Histocompatibility matching of tissue type Organ rejection https://www.youtube.com/watch?v=QGtLYtOwtxA

Medical Highlights Read in Class Pacemaker A pacemaker is a small device that's placed in the chest or abdomen to help control abnormal heart rhythms. This device uses low-energy electrical pulses to prompt the heart to beat at a normal rate. Pacemakers are used to treat arrhythmias. Arrhythmias are problems with the rate or rhythm of the heartbeat.

Cardiac resynchronization therapy improves the heart's efficiency and increases blood flow, patients have reported alleviations of some heart failure symptoms

Defibrillator a common treatment for life-threatening cardiac dysrhythmias and ventricular fibrillation. Defibrillation consists of delivering a therapeutic dose of electrical current to the heart with a device called a defibrillator.

Heart pumps The left ventricular assist device, or LVAD, is a mechanical pump that is implanted inside a person's chest to help a weakened heart pump blood throughout the body.