CARDIOVASULAR RESPONES TO EXERCISE Flashcards
what is the cardiovascular response to exercise?
increase muscle contraction which increases metabolic demand
what is the regulation used if just a small group of muscles are worked?
what is the effect if many muscle groups are used like in running?
local regulation to respond in decrease in oxygen and increase in adenosine production
increase cardiac output occurs as result of vasodilation in the capillary beds from local regulation decreasing the TPR decreasing BP affecting blood flow
what is the effect of sympathetics on exercise?
increase stroke volume and heart rate increasing cardiac output
also, vasoconstriction increases TPR
why do sympathetics fire during exercise?
activated by the premotor cortex causing the muscle contraction
what is the increase in blood flow to muscles from exercise?
what is the effect in severe bleeding? if prolonged?
20x increase in blood flow to muscles with small to moderate increase in systolic pressure and MABP
vasoconstriction occurs with severe bleeding but in the brain, heart, lungs
necrosis and toxicity
main causes of hypertension?
hyper secretion of renin
acute neurogenic hypertension
essential hypertension
juxtaglomerular tumor and renal artery stenosis is a result of?
hypersecretion of renin due to too little volume
strong sympathetic outflow leads to _____?
acute neurogenic hypertension due to too little volume and too much blood in the arteries so thus increase cardiac output and decrease vascular volume
this is due to 90-95% of hypertensive cases, causes are largely unknown and associated with excess weight and a sedentary lifestyle, i.e. obesity
essential primary hypertension
what is the effect of obesity?
increase cardiac output to meet adipose demands
increase sympathetic firing due to increase leptin
symp stim renin to increase angio II
increase in arterial pressure causes kidney to decrease urine formation to increase blood volume
what can we use to treat hypertension?
decrease blood volume
decrease blood volume in arteries
increase vascular volume
how do we decrease blood volume?
diuretics
how do we decrease blood volume in the arteries?
decrease CO with B1 antagonists
how do we increase vascular volume?
Ca channel blockers
ACE inhibitors
alpha 1 antagonists
as heart rate increases the percent of time per min increase or decrease for diastole or systole? this affects flow where?
decreases
diastole
coronary blood flow
what regulates coronary flow? what happens if this is occluded?
decrease oxygen or increase in adenosine
patient gets ischemic, decrease ATP production, depolarization failure leading to risk of circus rhythm causing fibrillation
what is the term for the event when a piece of plaque breaks loose and occludes the vessel downstream?
acute coronary artery occlusion
ischemic part of heart develops and is described as crushing chest pain and is produced by lactate, histamine, bradykinin?
what is this condition called
angina pectoris
how do we treat angina pectoris?
vasodilation to decrease afterloads
nitroglycerin for quick response or beta blockers used as a slower treatment
this condition develops over time and heart becomes gradually weaker which can affect right ventricle or left ventricle, no cure
what is this syndrome?
heart failure
drugs used to treat decompensated phase of heart failure?
digitalis
shock
what is shock?
caused by?
inadequate blood flow throughout body due to decrease CO or increase vascular volume
heart problems (decrease CO)
decreased venous return
what does shock result in?
decrease blood flow to heart and brain
what are the types of shock?
toxic shock
hypovolemic shock
neurogenic shock
anaphylactic shock
name this shock
endotoxins from bacteria
toxic shock
name this shock
profound blood loss
hypovolemic shock
name this shock
venous dilation from deep anesthesia
neurogenic shock
name this shock
allergic response causing mast cells to release histamines
anaphylactic shock
how do we treat shock?
increase venous return
sympathomimetic drugs
administer oxygen
this disease is a result of a stiffened valve that doesn’t open as a result of stenosis and so the heart has to increase pressure to pump the same SV, sounds are turbulent; note that blood flows back through valve known as regurgitation
valvular disease
