Cardiovascular System

I. Introduction The cardiovascular system consists of the heart, and vessels, arteries, capillaries, and veins. A functional cardiovascular system is vital for _________________________and ___________from them.

II. Structure of the Heart The ______is a hollow, cone-shaped, muscular pump within the __________. Size and Location of the Heart –The average adult heart is _______________wide. –The heart lies in the _______ under the sternum & ______________.

Average Size of Heart 14 cm long 9 cm wide

Coverings of the Heart –The __________encloses the heart –It is made of ___________; the outer, tough connective tissue fibrous __________ surrounding a more delicate visceral pericardium (____________that surrounds the heart. –Between the 2 pericardia is a space (______________) filled with fluid

Wall of the Heart –The wall of the heart is composed of __________________ –The outermost layer, the ____________, is made up of connective tissue and houses ___________ and ________________. –The middle layer called ____________consists of ____________and is the thickest layer of the heart –The inner layer is the ______________.

Heart Chambers and Valves –The heart has four internal chambers: ____________on the top and ____________ on the bottom. _______________returning to the heart from other parts of the body and have thin walls and ear-like auricles projecting from their exterior. The thick-muscled _________________________

Coronal Sections of Heart

–A __________ divides the atrium and ventricle on each side. Each also has an _____________________to ensure one way flow of blood. ________________________ –Both have cusps to which __________________(heart strings) attach.

______________are, in turn, attached to _______________in the inner heart wall that contract (pull) during ventricular contraction to ______________________through the A-V valves. –The _______________________bring de- oxygenated blood from the body to the right atrium. –The __________________than does the left ventricle because it pumps blood only as far as the lungs, compared to the ____________________________________ ____________________________________

–At the base of the ______________leading to the lungs, is the ______________, which ____________________________________ ____________________________________ –The __________________receives blood from five pulmonary veins. –The _____________pumps blood into the entire body through the _______, guarded by the aortic valve that prevents backflow of blood into the ventricle.

Path of blood through the Heart. –.–. –.–. –.–. –.–.

–.–. –.–. –.–.

Blood supply to the Heart Muscle –__________________ Feed the heart muscle with oxygenated blood. –__________________ Drain the blood from the heart muscle and carry it to the right atrium

III. Heart Actions Blood pressure is the force of blood against the inner walls of the arteries. The cardiac cycle consists of: –Atria beating in unison (___________) –Contraction of both ventricles __________________________________________ _________________________________________ –Then the entire heart relaxes for a breif moment (________________________________) ________ = ventricle contraction felt in the arteries

Heart sounds –___________are due to the vibrations in heart tissue as blood rapidly changes velocity within the heart. –Heart sounds can be described as a “lubb- dupp” sound, also called “___________” sounds –The “_____” occurs as ventricles contract –The “_____” occurs as ventricles relax

IV. Blood Vessels The blood vessels form a closed tube that carries blood away from the heart, to the cells, and back again to the heart. _______ are thick vessels adapted for carrying high presure blood _____ from the heart ________are the smallest vessels, through which substances are exchanged with cells _______ are thinner than arteries; they _____ blood to the heart.

Venous Valves

Venous Blood Flow not a direct result of heart action depends on skeletal muscle contraction depends on breathing

Life-Span Changes deposition of cholesterol in blood vessels heart enlarges cardiac muscle cells die fibrous connective tissue of heart increases adipose tissue of heart increases blood pressure increases resting heart rate decreases 15-70

Clinical Application Arrhythmias Ventricular fibrillation rapid, uncoordinated depolarization of ventricles Tachycardia rapid heartbeat Atrial flutter rapid rate of atrial depolarization 15-71