Heart Failure Flashcards
What is heart failure?
The inability of the heart to pump enough blood to the rest of the body, due to a structural or mechanical problem to do with ventricular filling or ejection
What are the risk factors for heart failure?
Male sex
Increased age
Diabetes
Smoking
50% of people diagnosed with heart failure die within 5 years, true or false?
True
What is the average age of diagnosis for heart failure?
76 years
What are the causes of heart failure?
Coronary artery disease Hypertension Cardiomyopathies Valvular heart disease Arrhythmias Chronic kidney disease
What are complications of heart failure?
Cardiac arrhythmias (usually AF and ventricular arrhythmias) Depression Cachexia Chronic kidney disease Sudden cardiac disease
What is the most common cause of heart failure?
Coronary artery disease
What is the definition of ejection fraction, and how is it calculated?
The fraction of blood volume ejected from the ventricles per beat
SV/EDV x100
What is systolic heart failure?
The heart can’t pump forcefully enough
What is ejection fraction in systolic heart failure, and why?
Reduced
The heart can’t pump enough blood out of the ventricles so SV is reduced, which reduces ejection fraction
What is systolic heart failure defined as, in terms of ejection fraction?
Ejection fraction of 35-40%
What is diastolic heart failure?
Heart is pumping forcefully enough but there isn’t enough preload (blood volume in ventricles before ejection)
What is ejection fraction in diastolic heart failure, and why?
Normal (about 70%) because SV and EDV are both reduced
What is left-sided heart failure usually caused by?
Systolic dysfunction
Why does atherosclerosis cause left-sided heart failure?
Less oxygenated blood gets through coronary arteries to the myocardium, so the heart does not have enough energy to contract forcefully enough
Why does a previous MI cause left-sided heart failure?
Scar tissue prevents myocardium from stretching so the heart can’t contract forcefully enough
Why does hypertension cause left-sided heart failure?
As aortic pressure increases it gets harder for ventricles to eject against the pressure
LV hypertrophies to compensate but eventually the muscle weakens leading to weaker contractions
Also the hypertrophy reduces the amount of space in the ventricle, decreasing preload and leading to diastolic heart failure
What is dilated cardiomyopathy and how does it cause left-sided heart failure?
Ventricular wall stretches and thins out to accommodate increased preload but contraction strength weakens
What is restrictive cardiomyopathy and how does it cause left-sided heart failure?
The ventricle becomes too stiff to contract properly, and also can’t stretch so preload is decreased
How does the body try to compensate for systolic dysfunction?
Activating the RAAS to increase blood flow
Causing fluid retention in the lungs