Chapter 7 Cardiovascular System
Function of the Cardiovascular System
The function of the cardiovascular system is to maintain an adequate supply of blood to all the tissues of the body.
What system controls the heart rate?
This is accomplished by the rhythmic contractions of the heart. Heart rate is controlled by the autonomic nervous system.
myocardium
muscle tissue of the heart
Pericardium
double-walled sac containing the heart
Epicardium
membrane that forms the inner most layer of pericardium and the outer surface of the heart
Endocardium
inner most layer of tissue that lines the chambers of the heart
Septum
separates the two aria (atrial septum) separates the two ventricles (ventricular septum
Systole
part of heartbeat when the heart muscle contracts and pumps blood from chambers to arteries
Diastole
phase of heartbeat when heart muscles relax and fills the chambers with blood
myocardial infarction
Heart attack; death of myocardial cells
Another name for and location of: Left atrioventricular valve (AV)
mitral valve, lies between left atrium and left ventricle
Another name for and location of: Right atrioventricular valve
tricuspid valve, between the right atrium and right ventricle
Flow of blood through heart
into inferior and superior vena cava > to right atrium > through tricuspid valve > to right ventricle > through the pulmonary valve > to pulmonary arteries > into lungs > to pulmonary veins > into left atrium > through left mitral valve > into left ventricle > through aortic valve > to aorta > rest of body
Most common congenital cardiac lesion
left to right shunts
Atrial Septal Defect
a hole in the wall (septum) between the two upper chambers of your heart(atria)
What does atrial septal defect cause
free communication between the two atria
What does atrial septal defect result from
lack of closure of the foramen ovule after birth
How does it appear radiographically
enlargement of the right ventricle and atrium and pulmonary outflow tract
Ventricular Septal Defect
opening between the left and right ventricles allowing blood to flow back into the right ventricle instead of entering the systemic circulation
How does ventricular septal defect appear radiographically
enlarged pulmonary trunk
Cardiomegaly
enlarged heart
How can you diagnose cardiomegaly from PA chest x-ray
evaluating the heart size with cardiothoracic ratio --- greater than 50% = cardiomegaly
Tetralogy of Fallot
combination of four congenital abnormalities. The four defects include a ventricular septal defect (VSD), pulmonary valve stenosis, a misplaced aorta and a thickened right ventricular wall (right ventricular hypertrophy
Most common cause of what
cyanotic congenital heart disease
Coarctation of the Aorta
narrowing or constriction of the aorta
Where does Coarctation of the Aorta commonly occur
just beyond the branching of the blood vessels to the head and arm
Classic sign of Coarctation of the Aorta
hypertension in children
Coronary Artery Disease
narrowing of the lumen of one or more of the coronary arteries
Most common cause of Coronary Artery Disease
atherosclerosis – deposition of fatty material on the inner arterial wall
Predisposing factors for CAD
HYTN – obesity – smoking – high cholesterol diet – lack of exercise
Congestive Heart Failure
inability of the heart to propel blood at the rate and volume sufficient to provide an adequate supply to the tissues
Congestive Heart Failure causes
intrinsic cardiac abnormality – HTN – obstructive process increasing resistance to blood flow
Pulmonary Edema
abnormal accumulation of fluid in the extravascular pulmonary tissue
Most common cause of Pulmonary Edema
elevation of pulmonary venous pressure
Other causes of Pulmonary Edema
left sided heart failure – lymphatic blockage - more
Hypertension
high blood pressure
Leading cause of Hypertension
strokes & CHF
Above what systolic/diastolic is one considered hypertensive
140/90
Aneurysm
localized dilation of an artery that most commonly involves the aorta
Saccular Aneurysm
involves one side of the arterial wall
Fusiform
aneurysm is bulging of the entire circumference of the vessel wall
Traumatic Aortic Rupture
potentially fatal complication of closed chest trauma
Aortic Dissection
potentially life-threatening condition in which disruption of the intima permits blood to enter the wall of the aorta and separate its layers
Atherosclerosis
thickening, hardening, and loss of elasticity in the arteria wall
Thrombus
intravascular clot
Embolism
thrombus that becomes detached and enters bloodstream
Valvular Disease
is characterized by damage to or a defect in one of the four heart valves: the mitral, aortic, tricuspid or pulmonary
Rheumatic Heart Disease
autoimmune disease that results from a reaction of the patients antibodies against antigens from a previous streptococcal infection
What does Rheumatic Heart Disease damage
Heart valves - mitral and aortic
Mitral Stenosis
narrowing of the mitral valve opening
Complication of Mitral Stenosis
rheumatic disease
Results from Mitral Stenosis
thickening of the valve by fibrous tissue, calcific deposits, or both
Aortic Stenosis
Narrowing of the valve in the large blood vessel branching off the heart (aorta).
causes of aortic stenosis
rheumatic heart disease
Aortic Insufficiency
A condition in which a heart valve doesn't properly close.
Aortic Insufficiency causes
rheumatic heart disease – syphilis – infective endocarditis – dissecting aneurysm – marfans syndrome
Pericardial Effusion
accumulation of fluid within the pericardial space surrounding the heart
Results from Pericardial Effusion
bacteria – viruses – neoplastic involvement – idiopathic pericardial effusion
Deep Venous Thrombosis
A blood clot in a deep vein, usually in the legs.
Primarily involves Deep Venous Thrombosis
lower extremities
DVT is major source of potentially fatal what?
pulmonary embolism
Varicose Veins
dilated, elongated, and tortuous vessels that most commonly involve the superficial veins of the leg just under the skin
Best non-invasive testing to diagnose
color flow Doppler ultrasound