Pathology Heart Failure

Question 1

what is systolic heart failure ?
what is diastolic heart failure ?
(2)

Answer 1

1- systolic hear failure =WEAK PUMPING, reduced ejection fraction
2-diastolic heart failure= filling PROBLEM

Question 2

what is the cause of left hearted heart failure ?
3 main points and explain
(6)

Answer 2

1- ischaemic disease (MI ) where coronary arteries are blocked
2-High BP means the pressure inside the arteries is too high. As the heart pumps against this pressure, it must work harder. Over time, this causes hypertrophy ( this ALSO squishes the coronary arteries and hence decreases Blood to myocardium =weaker contraction)
3- Dilated Cardiomyopathy = heart chamber walls stretch out and grow to keep inline with an increased pre load hence force of contraction becomes stronger FOR SHORT TERM BUT the heart muscle cell = too thin =weaker pumping

Question 3

compensatory mechanisms in hear failure?

6

Answer 3

Sympathetic activation to increase HR / VASOCONSTRICITON via baroreceptor reflex
this can be dangerous with heart failure because the heart is already weak :
-heart muscles suffer from hypertrophy
-apoptosis/necrosis
-conractile dysfunction , arrhythmia , sudden cardiac death!

RAAS activation to raise BP and increase Preload of heart in Heart failure will increase CO ( heart cant cope )

• water retention =oedema
• short term = works as it increase pre-load
• Long term =maladaptive = increases fluid retention, Ofer load, remodelling !

Question 4

what are the causes of diastolic (filling) heart failure ?

4

Answer 4

1- HT = muscle cells grow so much that the space in Ventricles = decreased = less space for filing

2-Aortic stenosis = narrow aorta ( harder to pump blood into aorta= hypertrophy=

3-RAAS = senses low bp hence works to increase Bp= INCREASES fluid retention, preload ,force of contraction = this can make heart failure worse in the long term as fluid leaks out from BV.

4-Back up of blood in lungs ( edema = dyspnea/ orthopnoea)

Question 5

how do we test for Heart failure ?

3

Answer 5

1-ECG-normal ECG can rule out heart failure
2-BNP=B type natriuretic peptide levels ( HIGH BNP = LOW EJECTION FRACTION hence heart failure )
3-Echocardiogram (calculate ESV / EDV = left ventricle ejection fraction to see if they have heart failure )

Question 6

how to manage heart failure?

5

Answer 6

1-reduce salt and water intake
2-blockade of unhelpful RAAS so use drugs that will block this: ACE inhibitors , AT1 antagonists, Mineralcortacoid receptors antagonist ( spironolactone)
3-Reduce SNS effect = Beta-blockers (decrease HR, hence CO)
4-Enhancing BNP system drug ( BNP helps vasodilation and increases diuresis )
5-reduce preload = diuretics

Question 7

how to manage heart failure ? (5)

Answer 7

1-reduce salt and water intake
2-blockade of unhelpful RAAS so use drugs that will block this : ACE inhibitors , AT1 antagonists , Mineralcortacoid receptors antagonist ( spiralactone )
3-Reduce SNS effect = Beta blockers (decrease HR , hence CO)
4-Enhancing BNP system drug, BNP levels need to increase = Sacubitril/valsartan is a combination product. Sacubitril is a pro-drug that upon activation STOPS the break down of BNP.
5-reduce preload = diuretics

Question 8

how do people get Right sided heart failure ?
(3)
think about causes and effects

Answer 8

1- Left –> right shunt due to septal defect
2-Chronic lung disease (hypoxia causes pulmonary arteriole constriction =directs blood to better perfused area= hence pulmonary BP increases –>hypertrophy )
3- Blood gets backed up in body ( backward failure )