Exam 3 - Readings (Cardioavascular) Flashcards
Term for fast heart rate.
Tachycardia
ECG results for patient with tachcardia.
Normal, however time intervals between QRS complex will generally be >100 beats/min.
Term for slow heart rate.
Bradycardia
A patient with a HR <60 beats/min can be diagnosed with what condition.
Bradycardia
Stimulation of this nerve causes bradycardia.
Vagus nerve
This tool measures the duration of interbals between successive QRS complexes in the ECG via height of successie peaks.
Cardiotachometer
A condition that may results from various condition altering the strength of the sympathetic and parasympathetic nerve signals to the heart sinus node.
Sinus arrhythmia
Blockage defined by sudden halting of P waves in an ECG, QRS-T complex is delayed but presents normally; due to sinus node impulse being blocked before it enters the atrial muscle.
Sinoatrial block
The only means by which an impulse can pass from the atria into the ventricle.
A-V bundle/Bundle of His
Blockage when P-R interval is >20 seconds.
First-degree heart block
Blockage that may occur fromt the following conditions: Ishemia/inflammaiton of the A-V node/A-V bundle fibers, compression of the A-V bundle via scar tissue, or extreme heart stimulation via the vagus nerve.
Atrioventricular block
Blockage defined as delay of conduction from the atria to the ventricles however there is not actual blockage of conduction.
First-degree heart block.
Blockage when P-R interval is 0.25-0.45 seconds.
Second-degree heart block
Blockage that demonstrates cases where an atrial P wave forms but is not followed with by a QRS-T wave.
Second-degree heart block
Second-degree heart block characterized by fixed number of nonconducted P waves for every QRS complex.
Type II
Second-degree heart block characterized by progressive prolongation of the PR interval until a ventricular beat is dropped.
Type I
Blockage characterized by complete blockage of impulse from the atria into the ventricles.
Third-degree heart block
Blockage where P waves are completely dissociated with QRS-T complexes.
Third-degree heart block
Term for ventricular excitability being initially suppressed due to the ventricles being driven by the atria at a rate greater than normal.
Overdrive suppression
Phenomenon that occurs due to overdrive suppression. When part of Purkinje system discharges rhythmically at a rate of 15-40 times per minutes and acts as the pacemaker for the ventricles.
Ventricular escape
Condition chararacterized by periodic fainting spells.
Stokes-Adams syndrome
A small battery-operated electrical stimulator planted beneath the skin connected to the right ventricle that maintains continued rhythmical impulses to the ventricles.
Artificial pacemaker
Term for a contraction that occurs before the time that normal contraction would have been expected.
Premature contraction
Main cause of premature contractions, emits abnormal impulses at odd times during the cardiac rhythm.
Ectopic foci
Condition that may result from the following causes: Local areas of ischemia, small calcified plaques within the heart, or toxic irritation of A-V node/Purkinje sysmer/myocardium.
Ectopic foci
Term for the interval between premature contractions and the next succeeding contraction which is slightly prolonged.
Compensatory pause
When the heart contracts before it should and the ventricles are not filled with blood normally and the stroke volume output during contraction is depressed or almost absent.
Pulse deficit
Results from incontrolable cardiac impulses within ventricular muscles leading to an endless cycle of stimulation.
Ventricular fibrillation
Causing factors of ventricular fibrillation.
Sudden electrical shock of the heart or ischemia of the heart muscle.
Ways that a cardiac impulse can “re-enter” the heart muscle.
Pathway us longer than normal, velocirt of conduction is decreased, or the refractory period of the muscle is shortened.
What effect would dilation of the heart have on the cardiac impulse pathway?
Increase the duration
What effect would blockage of the Purkinje system, ischemia of the heart, or high potassium levels have on a cardiac impulse?
Decrease its velocity
What effect would drugs such as epinephrine or repetitive electrical stimulation have on the refractory period of the heart muscle?
Decrease the refractory period
A patient’s ECG lacks P waves leading you to suspect what?
Atrial fibrillation
Main role of microcirculation.
Transport nutrients to tissues and remove cell excreta
Smooth muscles fiber that encricles a capillary, site at which a metarteriole becomes a capillary.
Precapillary sphincter
Thin-slit curving channel that lies between adjacent endothelial cells in capillary walls, where water soluble substances dissolve through the membrane.
Interceullar cleft
Small curve in endothelial cells that are thought to play a role in endocytosis
Caveolae
Organ associated with pores that form tight junctions and permit the movement of small molecules (i.e. oxygen, carbon dioxide, and water)
Brain
Organ associated with capillary pores that are wide open that nearly all dissolved substances may enter.
Liver
Organ associated with midsized capillary pores.
Gastrintestinal capillary membranes
Structure/Organ associated with oval window fenestrae capillary pores that make deep penetrations into the endothelial cells so that small molecules can filter through glomeruli without passing through the celft of endothelial cells.
Glomerular capillaries of the kidney
Intermittent contractions of the metarterioles and precapillary sphincters.
Vasomotion
What is the most significant regulator of vasomotion?
Oxygen concentration
Single most important means by which substances move between the plasma and interstitial fluid.
Diffusion
Oxygen and carbon dioxide are [water-soluble/lipid-soluble] substances.
Lipid soluble substances
[Lipid-soluble/water-soluble] substances can diffuse through endothelial membranes at any point without pores.
Lipid-soluble
Spaces between cells.
Interstitium
What are the two solid structures that make up interstitium?
Collagen and proteoglycan
Fluid in interstitium
Interstitial fluid
Osmotic pressure due to plasma proteins causing fluid movement via osmosis from the interstital spaces into blood.
Colloid osmotic pressure
Four factors that determine whether fluid will move out of the blood into the interstitial fluid or vice versa
Capillary pressure, interstitial fluid pressure, capillary plasma colloid osmotic presure, interstital fluid colloid osmotic pressure.
What direction does capillary pressure and interstitial fluid colloid osmotic pressure tend to make fluid move as it pertain to the capillary membrane?
Outward
What direction does interstitial fluid pressure and capillary plasma colloid osmotic pressure tend to make fluid move at it pertains to the capillary membrane?
Inward
System that removes excess fluid/protein molecules/debris/other matter from tissue spaces.
Lymphatic system
How does the lymphatic system effect the interstital fluid pressure?
Makes it negative
True/False: Superficial portions of the skin, the CNS, endomysium of muscles, and bones all have lymph channels.
False
Minute interstital channels that permit the flow of interstital fluid to lymphatic vessels.
Prelymphatics
Site at which lymph vessels of the lower part of the body empty into.
Thoracic duct
Where does lymph from the left side of the head, left arm, and parts of the chest drain?
Thoracic duct
Where does lymph from the right side of the head, the right arm, and parts of the thorax drain?
Right lymph duct
Where does lymph from the right lymph duct empty?
Right subclavian vein and internal jugular vein
How is most lymph reabsorbed? Where is the remaining lymph absorbed?
Through venous ends of blood capillaries; Lymphatic capillaries
Structures associated with lymphatic capillaries that allows absorbance of molecules with higher molecular weight (i.e. proteins).
Anchoring filaments
What lymph tends to have the highest protein concentration?
Liver and intestine
How is the lymphatic system important to nutrient absorption?
Major route for absorption especially as it pertain to fats in food
About how many liters of lymph flow through the body per day?
2-3 Liters
An increase in lymph flow will [increase/decrease] interstitial fluid pressure.
Increase
Factors that increase lymph flow.
Elevated capillary hydrostatic pressure, decreased plasma colloid osmotic pressure, increase interstital fluid colloid osmotic pressure, and increased permeabiltiy of the capillaries.
True/False: As interstital fluid begins to exceed atmospheric pressure it will continue to increase lymph flow.
False it will cap out
What causes pumping of the lymphatics (i.e. four factors)?
Contraction of surrounding skeletal muscles, movement of the parts of the body, pulsations of arteries adjacent to the lymphatics, and compression of the tissues by objects outside the body.
Generally, what two factors determine lymph flow?
Interstitial fluid pressure and activity of lymphatic pump
Aside from removal of excess fluid what other roles does the lymphatic system have?
Controls concentration of proteins within fluids/volume of interstital fluid/interstitial fluid pressure
What does the lymphatic systems ability to maintain negative interstital fluid pressure play a role in?
Holds tissues together by acting as a partial vacuum.
Artery that supplies nutrients to the heart.
Cornary arteries
Artery that supplies the anterior and left lateral portion of the left ventricle.
Left coronary artery
Artery that supplies most of the right ventricle and posterior part of the left ventricle.
Right coronary artery
Passage way by which coronary venous blood can return from the left ventricular muscle to the right atrium of the heart.
Coronary sinus
Passage way by which coronary venous blood can return from the right ventricular muscle to the right atrium.
Anterior cardiac veins
Passage way by which small amounts of coronary venous blood flows into all chmabers of the heart.
Thebesian veins
In the left ventricle coronary blood flow during systole is [>/=] coronary blood flow during diastole.
Artery found on outter surface of heart muscles, derived from epicardial arteries, supplies neeed nutrients.
Epicardial coronary arteries
Arteries that lie beneath beneath endocardium.
Subendocardial arteries
What is the primary control of coronary blood flow?
Local muscle metabolism
What influences coronary blood flow?
Oxygen demand of the heart
Direct effect of ANS on blood flow of heart.
Acetylcholine via vagus nerve and norepinephrine from sympathetic nerves via coronary vessels.
Indirect effects of ANS on blood flow of heart.
Secondary changes in coronary blood flow due to an increase/decrease in activity of heart.
What source of energy is used under resting conditions by the heart?
Fatty acid
What causes ischemic heart disease?
Insufficient coronary blood flow
Cholesterol build up in coronary arteries causing calcification which can block blood flow.
Atherosclerosis
Athlerosclerosis plaque
Thrombus
What permits coronary occulsion recovery?
Development of collateral channels between arteries
When there is little to no blood flow to a muscle in the heart such that it cannot maintain cardiac muscle function.
Infacrtion
Compression of heart due to blood flowing int pericardial cavity, right atrium will be unable to contract, and cardiac output will become insufficient.
Cardiac tamponade
