the heart is a hollow organ that lies in the
upper portion of heart
separate the atria from the ventricles
AV valve between the right atrium and right ventricle
AV valve between left atrium and left ventricle
thin strands of connective tissue that connects the AV valves to small mounds of myocardium (papillary muscles) that hold the valves in place
valves that prevent backflow of blood from the aorta and pulmonary arteries into the ventricles
Semilunar (SL) valves
when the ventricles contract, what opens that allows blood to flow out of the ventricles?
What percent of oxygen in the blood is taken out by the myocardium by means of the coronary arteries?
how does the heart receive freshly oxygenated blood?
L & R coronary arteries
the coronary arteries refill when the heart is?
heart attacks (myocardial infarctions) are usually caused by?
blocked coronary arteries
blockage of the left main coronary artery AKA?
"widow maker" because of its association with sudden death
largest vein that drains the heart
the coronary sinus drains unoxygenated blood into the?
two reasons for ischemia?
increased myocardial oxygen demand, reduced myocardial oxygen supply
chest discomfort caused by increased oxygen demand of the heart temporarily exceeds the bloods supply of oxygen.
what types of medication can resolve ischemia?
beta blockers (rest or slow the heart rate), nitroglycerin (increase coronary blood flow by dilating the coronary arteries).
what is an example of a clot busting drug that may help ischemia if an artery is blocked?
when blood flow to the heart muscle stops or is suddenly decreased long enough to cause cell death
Myocardial Infarction (MI)
chronic disease of the arterial system characterized by abnormal thickening and hardening of the vessel walls
thickening of fatlike deposits (plaque) in the inner lining of large and middle sized muscular arteries. can narrow the artery and interrupt blood flow to muscle.
what division of the autonomic nervous system is Norepinephrine the primary neurotransmitter for?
Sympathetic "fight or flight"
what division of the autonomic nervous system is Acetylcholine the primary neurotransmitter for?
Parasympathetic "feed and breed", "rest and digest"
sensors found in the internal carotid arteries and aortic arch that detect and compensate for a change in blood pressure
If BP drops, baroreceptors will cause?
peripheral blood vessel constriction, increase heart rate, increase the force of myocardial contraction
response to decreased BP that causes peripheral constriction, increased HR, increased myocardial contraction force?
Sympathetic (adrenergic) response
response to increased BP in which sympathetic stimulation is blocked or decreased
Parasympathetic (cholinergic) response
sensors in the internal carotid arteries and aortic arch that detect change in the bloods concentration of hydrogen ions(pH), oxygen, and carbon dioxide.
the two main types of cholinergic receptors:
Nicotinic, Muscarinic. Nicotinic receptors located in skeletal muscle. Muscarinic receptors located in smooth muscle.
what produces angiotensin, a powerful vasoconstrictor?
Renin. renin is released by kidneys during Beta1 stimulation
the force exerted on the walls of the ventricles at the end of diastole (end-diastolic volume)
"the greater the stretch of the cardiac muscle (within limits), the greater the resulting contraction"
Starling's law of the heart
condition in which the heart is unable to pump enough blood to meet the metabolic needs of the body
the pressure or resistance against which the ventricles must pump to eject blood
the lower the Afterload, the _________ blood can be ejected.
what do vagal maneuvers do?
slow the heart rate
asking the patient to cough, try to blow through an occluded straw, or bear down as if having a bowel movement, are all what?
types of Vagal Maneuvers
what can cause the heart to become dilated and flaccid(limp), slow the heart rate, and dramatically alter conduction?
Hyperkalemia (excess potassium) or hypocalcemia (decreased calcium levels)
what can cause the heart to go into a spastic contraction?
Hypercalcemia (excess calcium)
what supplies the right atrium and ventricle with blood?
Right coronary artery
the primary chemical mediator of the sympathetic division of the autonomic nervous system
the Circumflex Artery is a branch of the?
Left Coronary Artery
the anterior surface of the heart is made up mostly of the?
What is primarily responsible for parasympathetic stimulation of the heart?
the Vagus Nerves
coronary artery that supplies the SA node and AV node in most of the population
Right Coronary Artery
a semilunar valve is shaped like a?
a negative __________ effect refers to a decrease in heart rate
innermost layer of the heart?
the amount of blood flowing into the right atrium each minute from the systemic circulation
the ________ septum separates the right and left atria
a buildup of excess blood or fluid in the pericardial space can cause cardiac ____________.
specialized nerve tissue located in the internal carotid arteries and the aortic arch that detect changes in blood pressure?
one of the semilunar valves?
upper chambers of the heart?
the percentage of blood pumped out of a heart chamber with each contraction?
This typically results when the heart's demand for oxygen exceeds its supply from the coronary circulation
Sensors in the internal carotid arteries and aortic arch that detect changes in the concentration of hydrogen ions (pH), oxygen, and carbon dioxide in the blood?
When actin and myosin filaments slide together, the cardiac muscle ____________.
____________ in myocardial cells function as electrical connections and allow the cells to conduct electrical impulses very rapidly.
Space between the lungs that contains the heart, great vessels, trachea, and esophagus, among other structures.
This electrolyte is very important in cardiac muscle contraction.
This type of heart valve separates an atrium and ventricle.
Lower heart chambers
Pulmonary arteries and veins, aorta, superior and inferior vena cava?