Heart Failure Flashcards
what is considered heart failure?
when the heart is unable to produce an adequate cardiac output (CO) to meet metabolic needs
basically IMPAIRED PUMPING, FILLING OR BOTH
What is heart failure characterized by?
1) ventricular dysfunction
2) reduced exercise tolerance
3) diminished quality of life
4) shortened life expectancy
what are the 2 primary risk factors for HF?
1) CAD (coronary artery diseases)
2) Hypertension
what are some other contributing factors?
diabetes
tobacco
obesity
high serum cholesterol
what are the 4 factors that are affecting cardiac output?
1) preload : volume of blood in the ventricles at the end of diastole, before the next contraction
2) afterload : peripheral resistance against the LV
3) myocardial contractility
4) heart rate
what are the 3 types of heart failure?
1) heart failure with reduced ejection fraction (MOST COMMON)
- LV loses ability to generate enough pressure to eject blood forward
-systole
- Ejection fraction of 40% or lower
2) heart failure wit preserved ejection fraction
- ventricles cant relax and fill during diastole
- diagnosis happens based on symptoms of HF and normal Ejection fraction
3) mixed heart failure
- seen in dilated cardiomyopathy
- poor ejection fraction <35%
what are the 2 HF compensatory mechanism?
1) sympathetic nervous activation
- first and LEAST effective
- released of catecholamines (episode and norepinephrine)
2) neurohormonal responses
- kidney releases renin = RAAS
- pituitary releases ADH
- endothelium stimulated by ADH = Potent vasoconstrictor
what are the consequences of compensatory mechanisms?
1) enlargement of the chambers of the heart occurs when pressure in LV is elevated
2) Hypertrophy basically the heart muscle gets big
what is a counter regulatory process?
natriuretic peptides : atrial natriuretic peptide (ANP), b-type natriuretic peptide (BNP)
- released to increase atrial volume and ventricular pressure
what can you say about ANP and BNP with its storage?
ANP stored in granules of the atria and ventricles so even the smallest muscle stretch will release it
BNP stored in the ventricles so its release is triggered by increase pressure especially in LV
both of these promote venous and trial vasodilation. chronic HF will decrease both these hormones
what is Left sided HF?
MOST COMMON
- from left ventricular dysfunction caused by MI, CAD etc..
- backup of blood into the left atrium and pulmonary veins causes pulmonary congestion
What are the 3 findings of left sided HF?
1) Dyspnea and orthopnea
- develops as fluid accumulates in lungs
2) cough
- associated with fluid irritating the respiratory passages
3) paroxysmal nocturnal dyspnea
- pulmonary edema and occurs during sleep
- usually leads to pneumonia
what is right sided HF?
backup of blood into the right atrium and venous systemic circulation
caused by:
- cor pulmonate
- right ventricular MI
- Left side HF
What is signs of right side HF?
1) edema in the feet
2) listened jugular veins
3) hepatomegaly/slenomeagly
wha does chronic HF lead to?
ventricular remodelling
