 Cardiovascular System – Heart and Blood Vessels Topics in Human Pathophysiology Fall 2011 Gilead Drug Safety and Public Health

Outline  Blood continued  Hemopoiesis  Erythrocytes cont.  Platelets and Clotting  Heart  Structure  Cardiac cycle  Conduction System and ECGs  Coronary Circulation  Cardiovascular Disease – diagnosis and treatment

Blood Cell Genesis - Hemopoiesis

Blood Types

Disorders of Erythrocytes  Anemias  Blood Type mismatching – Acute Hemolytic Reaction  Hemolytic Reaction of the Newborn  Blood Doping - polycythemia

Agglutination in Blood Typing test

Hemolytic Disease of the Newborn

Platelets

Stages of Hemostasis

Disorders of Clotting  Thrombi and Emboli  Hemophilia  Thrombocytopenia  Impaired Liver Function

White Blood Cells - Leukocytes  Protect against pathogens by:  causing inflammation and fever  phagocytosing pathogens  creating antibodies to tag pathogens for destruction  killing pathogens in other ways  Creating a cadre of cells to fight reinfection by specific pathogens (immune memory)

Heart Structure

 Systole – ventricles contract, semilunar valves open to allow blood to large arteries; AV valves close to prevent backflow to the atria  Diastole – ventricles relax, semilunar valves close to prevent backflow into the ventricles, AV valves open to allow ventricles to fill  Cardiac Cycle video Cardiac Cycle video

 SA node is primary pacemaker  AV node is secondary pacemaker  AV bundle carries signal to ventricles  Electrical signal stimulates muscle contraction  For the conduction system to work properly adequate blood supply is required.

 Coronary artery disease  Myocardial ischemia  Myocardial hypoxia  Myocardial infarct  Myocardial necrosis

From wikipedia

Age Male sex Heredity Smoking Diabetes mellitus Hypertension High cholesterol Obesity Lack of exercise

 Diagnosis  BP monitoring  Symptoms  ECG  Angiogram  Stress Test  Nuclear myocardial perfusion tests

 For myocardial perfusion imaging (MPI)  A 2A adenosine receptor agonist  Vasodilates coronary arteries as if exercising  Injected into blood stream prior to gamma camera scan  Can give a good indication of myocardial perfusion

Treatment – Coronary bypass surgery – Angioplasty – Stents – Cholesterol lowering agents – Anticoagulents – Antianginal medications

 For angina  Thought to inhibit a sodium ion channel in the cardiac muscle cells  Contraction of those cells might normally cause compression of cardiac blood vessels during diastole.  Can be taken with other anti-anginal meds  Very effective

Congestive Heart Failure  Heart becomes weak  Blood backs up in veins and capillaries  Fluid excess in tissues  Symptoms include shortness of breath, edema, difficulty breathing (especially when lying down,) difficulty exercising

Congestive Heart Failure  Causes:  cardiomyopathy  hypertension  lung disease  coronary artery disease  previous MI  valve disease