Cardiac function and heart failure Flashcards
(22 cards)
What is heart failure?
The heart cannot pump enough blood around the body to meet the individuals needs
What problems with the heart cause heart failure?
The heart can’t fill properly or can’t eject with enough force
What are the stages of heart failure?
A - risk factors but no structural changes
B - Structural changes but no symptoms
C - Structural and functional changes (symptoms)
D - requiring treatment
What are the risk factors of heart failure?
Smoking/alcohol Previous heart attacks Heart valve disease Hypertension Coronary artery disease
What affect does heart failure have on after load, is this good or bad?
It increases in response to the low CO.
Initially this is good because it helps the heart peruse the organs but later it is bad because the heart has to work harder to pump
What affect does heart failure have on preload, is this good or bad?
Preload increases due to hypertension resulting in fluid retention.
Initially this is good because it maintains CO
But later can cause pulmonary oedema
What happens when the heart cannot pump enough blood and maintain BP?
Systemic vasconstriction
What is the consequence of systemic vasoconstriction?
Organs aren’t perfused as much
What are the direct causes of heart failure?
Problems with heart muscles or valves
What are the indirect causes of heart failure?
Hypertension - increased vascular resistance
What is hypertrophic cardiomyopathy?
Portion of the myocardium becomes enlarged causing functional impairment
What are the effects of hypertrophic cardiomyopathy?
Heart can’t fill with enough blood
Reduces EDV
Reduces systolic volume
Reduced CO
What is dilated cardiomyopathy?
Heart becomes enlarged and can’t pump blood efficiently
What are the effects of dilated cardiomyopathy?
Heart can’t pump blood with enough force.
Increased EDV
Reduced systolic volume
Reduced CO
What is valve stenosis?
Valves don’t fully open
Restricting blood flow
Extra strain on the heart to pump past restriction
What is valve incompetence?
Valves doesn’t close properly
Blood flows backwards
Extra statin on heart to pump required volume
What is coronary circulation?
Blood in the coronary arteries
What is the problem with oxygen delivery in the heart?
During contraction perfusion drops - very little oxygen delivery - pulsatile perfusion
What is hyperaemia?
Increased blood flow to tissues
What is active hyperaemia?
Increased blood flow to an organ associated with increased metabolic activity of the organ
What is reactive hyperaemia?
Increased blood flow following a period of ischemia e.g. pulsatile perfusion
What is athersclerosis?
Hardening of arteries due to plaque formation
