heart failure (HF) is also called
pump failure
heart failure
general term for the inability of the heart to work effectively as a pump
major types of HF are:
preload
volume of blood in the ventricles at the end of diastole (end of diastolic pressure)
preload is increased in
afterload
resistance left ventricle must overcome to circulate blood
afterload is increased in
increased afterload = increased ___
increased cardiac workload
ejection fraction (EF)
percentage of blood ejected from left ventricle during systole
- normal: 50-70%
- can be assessed with echocardiogram (ultrasound)
how is EF computed?
amount of blood pumped out of the ventricle divided by total amount of blood in ventricle
left-sided HF
formerly known as congestive heart failure
LV to LA to lung
two types:
- systolic: measured by EF (more common)
* 60% of cases are systolic HF
problem: left ventricle (muscle) is weak (thin) and blood backs up from the heart back into in the lungs *pump problem; fills but doesnt pump
typical causes of left-sided HF
classification of left-sided HF: ACC/AHA
A. Patients at high risk for developing heart failure; might have HTN, MI, coronary artery disease; but do not have symptoms
- teaching important!
B. Patients with cardiac structural abnormalities or remodeling who have not yet developed symptoms; chest x-ray or echo reveals valvular abnormality but do not have symptoms
- teaching important!
C. Patients with current or prior symptoms of heart failure.
D. Patients with refractory end-stage heart failure
NYHA staging: class 1
NYHA staging: class 2 (mild)
NYHA staging: class 3 (moderate)
NYHA staging: class 4 (severe)
NYHA staging: changes
right-sided HF: causes
right-sided HF
high-output failure: cardiac ouput
cardiac output remains normal or above normal
high-output failure: causes
caused by increased metabolic needs of hyperkinetic conditions such as:
- septicemia
- anemia (hgb around 5-6; prob getting blood transfusions)
- hyperthyroidism (T3, T4, TSH numbers out of wack)
compensatory mechanisms for heart failure
HF is caused by _____ in 75% of cases
systemic HTN