Part 20: CV & Renal Overview Flashcards
cardiac output = ____ x ___
stroke volume (SV) x HR
what is cardiac output?
how much blood can be pumped by the heart per min
what is stroke volume?
amount of blood pumped with each contraction
cardiac muscle contraction is generated by action potentials initiated by an _____ system in the heart
intrinsic electrical
cardiac processes are modulated by the ____ nervous system
autonomic
t/f at a cellular level, cardiac myocytes have a lot of similarity to the neurons and muscle cells
t
what is the primary difference between cardiac cells and neurons and muscle cells?
cardiac cells are receiving AP and contracting betwn 50-150x per min
when cardiac myocytes is stimulated by an AP, ____ions enter the cell through ___ channels, causing membrane ___, which causes the opening of ____ channels
Na; voltage gated Na channels; depolarization; voltage gated Ca
which ion is the key mediator in cardiac contraction?
Ca
cardiac myocytes store large amounts of ca in ___ and ____
organelles and the SR
when voltage gated Ca channels in cardiac myocytes are opened, some Ca enters and interacts with receptors in the _____ to generate a large efflux of Ca
SR
what is it called when Ca stimulates the SR to release more Ca?
ca induced Ca release
what is the purpose of Ca induced Ca release?
provides a large amounts of intracellular Ca available to interact with the myofilaments and initiate contraction
how do cardiac myocytes relax?
ATPase pumps are used to pump Ca out of the cytosol to allow relaxation. The Na/Ca exchanger and Na-K ATPase also contribute
t/f the process of all this ca movement happens every time our heart beats
t
t/f BV are dynamic tissues
t
t/f BV determine the resistance to blood flow and how easily blood gets to its destination
t
give an example of the baroreceptor reflex
when sitting or lying down, bp tends to be lower, bc gravity isnt pulling our blood away from the heart, when we stand up the body needs to counteract this change and baroreceptors sense this and increase BP
aldoesterone regulates how much ___ and ____ are retained in the body
Na and water
what is the 1st leading cause of death in Canada?
cancer
what is the 2nd leading cause of death in Canada?
heart disease
t/f mortality related to CVD has been on the decline
t
why has CVD mortality been on the decline?
early detectation, education to the public and improved treatent strategies and understanding
what are the 4 main types of CVD?
- arrythmias
- heart failure
- coronary artery disease
- hypertension
what are arrythmias?
dysfunction or dysregulation of the electrical activity of the heart
what is heart failure?
when the heart muscle undergoes changes that makes it less efficient in pumping blood
when people are talking about MI and stroke, they are referring to _____
CAD
what is atherosclerosis?
build up of lipids in the BV causing the narrowing & increased resistance to blood flow
what can atherosclerosis lead to?
obstruction can cause angina and full occlusion of a vessel can cause an MI or stroke
ischemic heart disease is alos known as ___
angina
t/f hypertension doesnt have a specific location, but high BP can be damaging to organs and precipitate other CVDs like an MI in a patient with CAD
t
incidence of Canadians being diagnosed with CV related diseases is now ____ (lowe/higher) than previous generations
lower
list broad category risk factors for CVD (10)
- age, sex, ethinicity
- family history
- unhelathy diet (high sodium, fat, processed)
- overweight, low physical activity
- tobacco use
- high alocohol consumption (>1-2 drinks/day)
- high BP
- high cholesterol
- diabetes and other chronic health conditions
- stress
which ethnic groups have higher risk of CVD?
indigenous, south asian, african
what family history puts a patient at higher risk?
first degree relative that has/had CVD
what are 2 main goals of treating hypertension?
reduce BP and reduce the risk of developing other CVD
what are 3 goals when treating CAD?
- reduce athersclerosis
- reduce risk of blood clots
- manage symptoms of ishcemic heart disease
what are 2 goals when treating heart failure?
- improve cardiac output
2. manage congestive heart failure
what are 2 goals when treating arrhythmias?
- reduce abnormal rhythms
2. reduce risk of blood clots
what are the primary preventative medications for CVD?
antihypertensives and lipid lowering agents
