Week 5 - Cardiovascular System PDF

Week 5 Human Anatomy & Physiology - 1 (HMG380) CARDIOVASCULAR SYSTEM Dr. Merin Thomas [email protected] Office hours : Monday & Wednesday, 3:00pm to 5:00pm Tues...

Week 5 Human Anatomy & Physiology - 1 (HMG380) CARDIOVASCULAR SYSTEM Dr. Merin Thomas [email protected] Office hours : Monday & Wednesday, 3:00pm to 5:00pm Tuesday & Thursday 1:00pm to 3:00pm  Learning Objectives BLOOD BLOOD VESSELS HEART  OVERVIEW OF THE CARDIOVASCULAR SYSTEM The cardiovascular system consists of three interrelated components 1. Blood 2. Blood vessels 3. Heart  Levels of Structural Organization - LEVEL 3 - TISSUE LEVEL Epithelial Tissue Connective Tissue Muscular Tissue Nervous Tissue Covers body surfaces, Contracts to make body lines hollow organs & Connects, supports, and protects Carries information parts move & in the from one part of the cavities, and forms body organs while distributing process generates heat body to another glands. blood vessels to other Loose tissues Connective Smooth Muscle through nerve Based on shape of Tissue impulses the cell 2 types of cells Dense Connective Tissue Skeletal Muscle Based on number Cardiac Muscle of layers of cells Special Connective Tissue Three parts: CNS, PNS, ANS  CARDIOVASCULAR SYSTEM - BLOOD Blood is a liquid connective tissue that consists of cells surrounded by a liquid extracellular matrix. The extracellular matrix is called blood plasma, and it suspends various cells and cell fragments.  CARDIOVASCULAR SYSTEM - BLOOD - FUNCTIONS 1. Transports oxygen, carbon dioxide, nutrients, hormones, heat, and wastes. 2. Regulates pH, body temperature, and water content of cells. 3. Protects against blood loss through clotting, and against disease through phagocytic white blood cells and proteins such as antibodies, interferons, and complement.  BLOOD - PHYSICAL CHARACTERISTICS Blood is denser and more viscous than water. The temperature of blood is 38°C, about 1°C higher than oral or rectal body temperature Slightly alkaline pH ranging from 7.35 to 7.45 (average = 7.4). The color of blood varies with its oxygen content. Blood constitutes about 20% of extracellular fluid, amounting to 8% of the total body mass. The blood volume is 5 to 6 liters in an average-sized adult male and 4 to 5 liters in an average-sized adult female.  CARDIOVASCULAR SYSTEM - BLOOD - COMPONENTS WHOLE BLOOD BLOOD PLASMA PROTEINS ALBUMINS 54 % BLOOD 8% PLASMA 7% GLOBULINS 38% 55% FIBRINOGEN 7% ALL OTHERS 1% WATER 91.5% - ELECTROLYTES - NUTRIENTS - GASES - REGULATORY SUBSTANCES OTHER OTHER SOLUTES 1.5% - WASTE PRODUCTS FLUIDS & TISSUES PLATELETS 92% FORMED 1,50,000-4,00,000 ELEMENTS NEUTROPHILS 60-70% 45% WHITE BLOOD CELLS 5,000- LYMPHOCYTES 20-25% 10,000 MONOCYTES 3-8% EOSINOPHILS 2-4% RBCs (44%), BASOPHILS 0.5-1% WBCs & RED BLOOD CELLS 4.8- PLATELETS 5.4MILLION (1%) BODY WEIGHT VOLUME FORMED ELEMENTS; No/μL  BLOOD - FORMATION OF BLOOD CELLS Hemopoiesis (hematopoiesis) is the process that produces the formed elements of the blood. Hemopoiesis takes place in the red bone marrow found in the epiphyses of long bones, flat bones, vertebrae, and the pelvis. Within the red bone marrow, hemopoietic stem cells ( hemocytoblasts) divide to produce various “blast” cells. Each of these cells matures and becomes a particular formed element. Erythropoiesis: the process of making erythrocytes Leukopoiesis: the process of making leukocytes Thrombopoiesis: the process of making platelets Pluripotent Stem Cells  BLOOD CHARACTERISTICS & FUNCTIONS OF FORMED ELEMENTS  Name CHARACTERISTICS FUNCTIONS Size: 7-8μm diameter, Red Blood Cells Shape: biconcave discs Hemoglobin within RBCs transports (RBCS) Or Nuclei: no nuclei, Oxygen and part of CO2 in blood Erythrocytes Life - ~120days White Blood Life: Most live for a few hours to a few Combat pathogens and other foreign Cells (WBCS) Or days. substances that enter body. Leucocytes Size: 10-12μm diameter, Phagocytosis. Destruction of bacteria Nucleus: has 2-5lobes; granulated Neutrophils with lysozyme, defensins, and strong nucleus, oxidants Cytoplasm: pale lilac granules Size: 10–12 μm diameter; Combat effects of histamine in Eosinophils Nucleus: usually has 2 lobes; allergic reactions, phagocytize Cytoplasm: large, red-orange granules fill antigen–antibody complexes Size: 8-10μm diameter Liberate heparin, histamine, and Nucleus: has 2 lobes, serotonin in allergic reactions that Basophils Cytoplasm: large granules, deep blue intensify overall inflammatory purple response.  NAME CHARACTERISTICS FUNCTIONS Mediate immune responses, Size: Small lymphocytes are 6–9 μm in including antigen–antibody reactions. B cells develop into plasmocytes, Lymphocytes (T diameter; large lymphocytes are 10–14 which secrete antibodies. cells, B cells, and μm in diameter; T cells attack invading viruses, cancer natural killer Nucleus: is round or slightly indented; cells, and transplanted tissue cells. cells) Cytoplasm: forms rim around nucleus Natural killer cells attack wide variety that looks sky blue; of infectious microbes and certain spontaneously arising tumor cells. Size: 12–20 μm diameter; Nucleus: is kidney or Phagocytosis (after transforming into Monocytes Horseshoe shaped; fixed or wandering macrophages). Cytoplasm: blue-gray and appears foamy. Size: 2–4 μm diameter cell fragments Life: live for 5–9 days Form platelet plug in hemostasis; release chemicals that promote PLATELETS Cytoplasm: contain many vascular spasm and blood clotting. vesicles Nucleus: no nucleus.  BLOOD - BLOOD GROUPS AND TYPES The surfaces of erythrocytes contain antigens composed of glycoproteins and glycolipids called agglutinogens Based on the presence or absence of various antigens, blood is categorized into different blood groups. Within a given blood group, there may be two or more different blood type. There are at least 24 blood groups and more than 100 antigens that can be detected on the surface of red blood cells. Two major blood groups—ABO and Rh.  CARDIOVASCULAR SYSTEM - BLOOD - ABO BLOOD GROUP The ABO blood group is based on two glycolipid antigens called A and B. People whose RBCs display only antigen A have type A blood. Those who have only antigen B are type B. Individuals who have both A and B antigens are type AB Those who have neither antigen A nor B are type O. Blood plasma usually contains antibodies called agglutinins that react with the A or B antigens if the two are mixed. Anti-A antibody, which reacts with antigen A Anti-B antibody, which reacts with antigen B RED BLOOD CELLS BLOOD PLASMA TYPE TYPE TYPE TYPE BLOOD TYPE A B AB O  CARDIOVASCULAR SYSTEM - BLOOD - ABO BLOOD GROUP - TRANSFUSIONS A transfusion is the transfer of whole blood or blood components into the bloodstream. Most often given to alleviate anemia, to increase blood volume or to improve immunity. The normal components of one person’s RBC plasma membrane can trigger damaging antigen–antibody responses in a transfusion recipient. In an incompatible blood transfusion, antibodies in the recipient’s blood plasma bind to the antigens on the donated RBCs, which causes agglutination or clumping, of the RBCs. Hemolysis  To be completed in class.. BLOOD TYPE CHARACTERISTIC A B AB O Agglutinogen (antigen) on RBCs A B BOTH A & B NEITHER A NOR B Agglutinin (antibody) in blood NEITHER ANTI-A BOTH ANTI-A AND plasma ANTI-B ANTI-A NOR ANTI-B ANTI-B Compatible donor blood types (no hemolysis) A,O B,O A,B,AB,O O Incompatible donor blood types (hemolysis) B,AB A,AB - A,B,AB People with type AB blood do not have anti-A or anti-B antibodies in their blood plasma. They are sometimes called universal recipients because theoretically they can receive blood from donors of all four blood types People with type O blood have neither A nor B antigens on their RBCs and are sometimes called universal donors because theoretically they can donate blood to all four ABO blood types. Type O persons requiring blood may receive only type O blood  CARDIOVASCULAR SYSTEM - BLOOD - RH BLOOD GROUP The Rh blood group so named because the antigen was discovered in the blood of the Rhesus monkey. + People whose RBCs have Rh antigens are designated Rh (Rh positive); − those who lack Rh antigens are designated Rh (Rh negative). Normally, blood plasma does not contain anti-Rh antibodies. If an Rh− person receives an Rh+ blood transfusion, however, the immune system starts to make anti-Rh antibodies that remain in the blood. If a second transfusion of Rh+ blood is given later, the previously formed anti-Rh antibodies cause agglutination and hemolysis of the RBCs in the donated blood, and a severe reaction may occur. CARDIOVASCULAR SYSTEM - BLOOD - RH BLOOD GROUP  CARDIOVASCULAR SYSTEM - HEART Heart is a hollow, somewhat conical, muscular organ Situated in the middle mediastinum, between the two lungs, posterior to the sternum and anterior to the vertebral column.  CARDIOVASCULAR SYSTEM - HEART Covered by Pericardium : Membrane covering the heart. Made up of two layers Pericardial cavity; capillary layer of pericardial fluid  CARDIOVASCULAR SYSTEM - HEART Layers of the Heart - 3 layers Epicardium Myocardium Endocardium  CARDIOVASCULAR SYSTEM - HEART - CHAMBERS OF THE HEART Consists of FOUR chambers Two are RECEIVING chambers Right Atrium & Left Atrium Two are PUMPING chambers Right Ventricle & Left Ventricle 29  CHAMBERS OF THE HEART 11. Right Atrium 12. Left Atrium 13. Right Ventricle 14. Left Ventricle 30 CARDIOVASCULAR SYSTEM - HEART - CHAMBERS OF THE HEART Right Atrium Receives deoxygenated blood (Venous blood) from whole body through large veins – Superior Vena Cava (SVC) Inferior Vena Cava (IVC) Right Ventricle Deoxygenated blood (venous blood) from right atrium enters through an opening guarded by the tricuspid valve and pumps it to the lungs via the pulmonary trunk 31  CARDIOVASCULAR SYSTEM - HEART - CHAMBERS OF THE HEART Left Atrium Receives oxygenated blood from the lungs via the pulmonary veins Left Ventricle Oxygenated blood from left atrium enters through an opening guarded by the bicuspid valve and it pumps it to the rest of the body via the aorta 32 33  CARDIOVASCULAR SYSTEM - HEART - CHAMBERS OF THE HEART - INTERIOR Right Atrium: Openings of SVC, IVC, Cornary Sinus; Tricuspid Valve Right Ventricle: Opening of pulmonary trunk; guarded by pulmonary valve. Valve complex Left Atrium: Opening of pulmonary veins Bicuspid Valve Left Ventricle: Wall much thicker than right ventricle; Valve complex ; Opening of aorta, guarded by aortic valve 34 CARDIOVASCULAR SYSTEM - HEART - CHAMBERS OF THE HEART - INTERIOR ARCH OF AORTA SVC PULMONARY TRUNK LEFT PULMONARY ATRIUM VALVE RIGHT AORTIC ATRIUM VALVE BICUSPID VALVE TRICUSPID VALVE LEFT VENTRICLE RIGHT VENTRICLE IVC 35  CARDIOVASCULAR SYSTEM - HEART - CHAMBERS OF THE HEART - VALVES Tricuspid valve 36  CARDIOVASCULAR SYSTEM - HEART - CHAMBERS OF THE HEART Tricuspid valve 37  CARDIOVASCULAR SYSTEM - HEART - CHAMBERS OF THE HEART Bicuspid valve/ Mitral Valve 38 CHAMBERS OF THE HEART - Valves 39 CARDIOVASCULAR SYSTEM - HEART - EXTERNAL FEATURES OF THE HEART Grooves separating chambers Crux LEFT ATRIUM Interatrial groove RIGHT ATRIUM RIGHT VENTRICLE LEFT VENTRICLE Atrioventricular groove CRUX Posterior interventricular groove 40  CVS- HEART - EXTERNAL FEATURES OF THE HEART Within the grooves are present the blood vessels that supply the heart Heart gets its main blood supply from the right and left coronary artery and their branches Right coronary, originates in the arch of aorta and is in the right atrioventricular groove Left coronary, originates in the arch of aorta and its largest branch Left anterior descending artery; Br. Of left coronary – anterior interventricular groove Posterior descending artery; Br. Of right coronary – posterior interventricular groove Coronary Sinus – Posterior atrioventricular groove ARTERIES AND VEINS WITHIN THE GROOVES 42  CARDIOVASCULAR SYSTEM - HEART - Great Vessels of the heart The great vessels of the heart are several vessels associated directly with the heart. These are the ascending aorta, the pulmonary trunk, the pulmonary veins, the superior vena cava, and the inferior vena cava The branches from the arch of aorta supply the upper limb, head & neck CARDIOVASCULAR SYSTEM - HEART - CONDUCTING SYSTEM OF THE HEART Bundle of His 46 Purkinje Fibers  CARDIOVASCULAR SYSTEM - HEART - ELECTROCARDIOGRAM - ECG As action potentials propagate through the heart, they generate electrical currents that can be detected at the surface of the body. An electrocardiogram abbreviated either ECG or EKG, is a recording of these electrical signals. The ECG is a composite record of action potentials produced by all the heart muscle fibers during each heartbeat. The instrument used to record the changes is an electrocardiograph.  CARDIOVASCULAR SYSTEM - HEART - SYSTEMIC CIRCULATION AND PULMONARY CIRCULATION system of blood vessels that forms a closed circuit between the heart and the lungs / trunk system of blood vessels that forms a closed circuit between the heart and the rest of the body  CARDIOVASCULAR SYSTEM - HEART - SYSTEMIC CIRCULATION AND PULMONARY CIRCULATION  CARDIOVASCULAR SYSTEM - HEART - CARDIAC CYCLE A single cardiac cycle includes all the events associated with one heartbeat. A cardiac cycle consists of systole and diastole of the atria plus systole and diastole of the ventricles. systole refers to the phase of contraction diastole refers to the phase of relaxation (dilation or expansion)  0.4 sec 0.3 sec 0.1 sec ATRIAL VENTRICULAR SYSTOLE RELAXATION PERIOD SYSTOLE  CARDIOVASCULAR SYSTEM - HEART - HEART SOUNDS Auscultation the act of listening to sounds within the body, is usually done with a stethoscope. The sound of the heartbeat comes primarily from blood turbulence caused by the closing of the heart valves. Smoothly flowing blood is silent. During each cardiac cycle, there are four heart sounds, but in a normal heart only the first and second heart sounds (S1 and S2) are loud enough to be heard through a stethoscope  CARDIOVASCULAR SYSTEM - HEART - HEART SOUNDS The first sound (S1), which can be described as a lubb sound, is louder and a bit longer than the second sound. S1 is caused by blood turbulence associated with closure of the AV valves soon after ventricular systole begins. The second sound (S2), which is shorter and not as loud as the first, can be described as a dupp sound. S2 is caused by blood turbulence associated with closure of the SL valves at the beginning of ventricular diastole. Although S1 and S2 are due to blood turbulence associated with the closure of valves, they are best heard at the surface of the chest in locations that are slightly different from the locations of the valves USE THIS AS A GUIDE FOR YOUR PRACTICALS  CARDIOVASCULAR SYSTEM - HEART - CARDIAC OUTPUT Cardiac output (CO) is the volume of blood ejected from the left ventricle (or the right ventricle) into the aorta (or pulmonary trunk) each minute. Cardiac output equals the stroke volume (SV), the volume of blood ejected by the ventricle during each contraction, multiplied by the heart rate (HR), the number of heartbeats per minute: CO = SV × HR (mL/min) (mL/beat) (beats/min)  CARDIOVASCULAR SYSTEM - HEART - CARDIAC OUTPUT CALCULATE CO IN A TYPICAL RESTING ADULT where stroke volume averages 70 mL/ beat, and heart rate is about 75 beats/min. Thus, average cardiac output is Will× 75 CO = 70 mL/beat bebeats/min calculated in class.. = 5250 mL/min = 5.25 L/min This volume is close to the total blood volume, which is about 5 liters in a typical adult male  CARDIOVASCULAR SYSTEM - BLOOD VESSELS Arteries carry oxygenated blood Veins carry deoxygenated/ venous blood Exception to this rule.. STRUCTURE OF BLOOD VESSEL  Tunica media more thicker in arteries than in veins Arteries have thick walls with muscles Veins have thin walls  CARDIOVASCULAR SYSTEM - BLOOD VESSELS Blood pressure is the pressure of blood pushing against the walls of your arteries  CARDIOVASCULAR SYSTEM - BLOOD VESSELS Systolic blood pressure (SBP) is the highest pressure attained in arteries during systole Diastolic blood pressure (DBP) is the lowest arterial pressure during diastole  Hypertension is classified into two different categories: 1.Primary Hypertension: Also called essential hypertension, where there is no known cause. This type of hypertension develops slowly due to lifestyle, environment, or age. 2.Secondary Hypertension: This type of hypertension is secondary due to health problem or medicine.  CARDIOVASCULAR SYSTEM – HEART RATE Heart rate or pulse, is the number of times the heart beats per minute. Resting heart rate is the heart pumping the lowest amount of blood needed - heart rate is normally between 60 and 100 beats per minute TACHYCARDIA - heart rate over 100 beats a minute BRADYCARDIA - a slower than normal heart rate USE THIS AS A GUIDE FOR YOUR PRACTICALS CARDIOVASCULAR SYSTEM – Arterial Pulse Points CARDIOVASCULAR SYSTEM - BLOOD VESSELS - MAJOR ARTERIES Descending thoracic aorta CARDIOVASCULAR SYSTEM - BLOOD VESSELS - MAJOR VEINS  TOPICS FOR ILLUSTRATION DRAW A NEAT LABELLED DIAGRAM OF THE GIVEN TOPICS ON PLAIN A4 SIZE PAPER – FOLLOW RUBRICS COMPLETED DIAGRAMS TO BE SUBMITTED FOR CORRECTION ON 30.09.2024 – sections 22/66 & 33/77 (Mon/Wed) 08.10.2024 – sections 44/88 (Tue/Thurs) Internal features of heart  REFERENCES Tortora, Gerard J. And Bryan H Derrickson. Principles of Anatomy and Physiology. John Wiley & Sons, 2020 Standring, Susan. Gray’s Anatomy E-Book. Elsevier Health Sciences, 2015.