Ch. 9-Cardiovascular System Flashcards
How many times does the heart beat each day?
100,000; 8,000 liters of blood
What does the cardiovascular system do?
Circulates blood by action of the heart, provides cells with oxygen and nutritive elements and removes waste and carbon dioxide
Where does blood flow?
Through the heart to the lungs, then back to the heart and out of the body
Heart
Center of cardiovascular system where vessels originate and return, weighs 300g, circulates blood through lungs and body
Pulmonary circulation
Lung circulation
Systemic circulation
Circulation through the rest of the body
3 Layers if the Heart
Endocardium, myocardium, pericardium
Endocardium
Inner lining of the heart
Myocardium
Muscular middle layer of heart
Pericardium
Outer membranous sac surrounding the heart
Arteries
Branching systems of vessels that transport blood from the right and left ventricles to all body parts
They always have a pulse
Veins
Transport blood from tissues back to the heart
Capillaries
Microscopic blood vessels connecting arterioles with venules
-passage of life sustaining fluids containing oxygen and nutrients
Blood
Consists of formed elements (erythrocytes, thrombocytes, leukocytes) and plasma
-delivers necessary substances to cells and transports waste
Septum
Divides heart into sections called the right and left heart
Atria
Two upper chambers, separated by interatrial septum, designated as right or left depending on which side of the septum they are on. They receive blood from the body
Ventricles
Two lower chambers, separated by interventricular septum, designated as right or left depending on which side of the septum they are on. Pump blood out to body
Right atrium
RA
Receives blood from body. Superior and inferior vena cava bring deoxygenated blood here, fills atrium, then passes through tricuspid valve to the right ventricle
Right ventricle
RV
Receives blood from right atrium through tricuspid valve, contracts to force blood through pulmonary valve into left and right pulmonary arteries, which then carry it to the lungs where it is oxygenated
Pulmonary arteries
Only artery that carries oxygen-deficient blood
Left atrium
LA
Receives blood from left and right pulmonary veins from lungs, fills atrium and creates pressure that forces oxygenated blood through the mitral (bicuspid) valve and into left ventricle
Left ventricle
LV
Receives blood from left atrium through mitral valve, contracts when filled, closing the mitral valve and opening the aortic valve. The blood is pumped from the aorta all over the body through arteries and capillaries
Tricuspid valve
Right atrioventricular valve
Guards opening between right atrium and right ventricle
Pulmonary valve
Semilunar valve
Guards opening between right ventricle and pulmonary artery
Mitral valve
Bicuspid valve
Left atrioventricular valve
Between left atrium and left ventricle
Aortic valve
Semilunar valve
Between left ventricle and aorta
Coronary arteries
Part of hearts own vascular system that delivers oxygen rich blood to the heart
Cardiac veins
Part of hearts own vascular system that collects oxygen poor blood and returns it to the right atrium
Heartbeat
Controlled by autonomic nervous system and generated by specialized neuromuscular tissue that causes cardiac muscle to contract
3 Things in Heart’s Specialized Neuromuscular Tissue
Sinoatrial node, atrioventricular node, and atrioventricular bundle
Sinoatrial node
SA node
Located in right atrium below superior vena cava, pacemaker of the heart, network of Purkinje fibers that discharge electrical impulses
Purkinje fibers
Atypical muscle fibers
Atrioventricular node
AV node
Beneath endocardium of right atrium and transmits electrical impulses to the bundle of His
Atrioventricular bundle
bundle of His
Collection of heart muscle cells specialized for electrical conduction that transmits impulses from the AV node to Purkinje fibers, which distribute it to ventricular muscle
Average adult heartbeat?
60-90 bpm
What affects the rate of heartbeat?
Emotion, smoking, disease, body size, age, stress, environment, and many others
Electrocardiogram
ECG, EKG
Records heart’s electrical activity
3 Commonly Used Sites for Taking Pulse
Radial artery, brachial artery, carotid artery
Auscultation
Taking pulse with stethoscope and counting for one minute
Apical pulse
Taking pulse right over the heart as with a stethoscope
Temporal artery
Temple area of head, used to control bleeding from the head and to monitor circulation
Carotid artery
Neck, easiest to access in an emergency
Brachial artery
Antecubical space of elbow, common for blood pressure
Radial artery
Thumb side of wrist, most common for pulse
Femoral artery
Groin area, used to monitor circulation
Popliteal artery
Behind the knee, used to monitor circulation
Dorsalis pedis artery
On dorsal surface of foot (top), used to assess for peripheral artery disease (PAD)
Blood pressure
BP
Pressure exerted by blood on artery walls, consists of systolic and diastolic number and measured by sphygmomanometer
Needs to be below (120/80)
Systolic number
Numerator and higher number, pressure while heart contracts
Diastolic number
Denominator and lower number, pressure while heart relaxes between beats
Pulse pressure
Difference between systolic and diastolic readings and indicates tone of arterial walls. Should not be over 50 or under 30
Arteriosclerosis
Hardening of the arteries
Atherosclerosis
Fatty plaques in arterial walls
Cardiovascular disease can accelerate due to
Reduced blood flow
Elevated blood lipids
Detective endothelial repair
Heart failure
One of the most common types of cardiovascular disease in older adults
Congestive heart failure
CHF
Left sided failure
Symptoms are pulmonary edema, dyspnea, shortness of breath
Right ventricular heart failure
Right sided failure
Usually occurs as a result of CHF
Symptoms are liver enlargement, distention of neck veins, edema in ankles
Stent
Steel cage like object is placed over a balloon catheter and inserted into the blockage, expanded, and removed so that the stent stays in place
Digitalis drugs
Strengthen heart muscle, increase force of systolic contraction, slow heart rate, and decrease conduction through the atrioventricular node