Heart Failure

Question 1

What is chronic heart failure?

Answer 1

This is when the heart is unable to pump a enough blood to meet the metabolic need of the tissue

Question 2

Physiological mechanism that maintains arterial bp and organ perfusion

Answer 2

1. Frank sterling mechanism- increases end-diastolic filling volumes
   Increase in ventricular dilation leads to ^ in oxygen requirement of the myocardium
2. Myocardial adaptation- hypertrophy with or without cardiac chamber dilation ( increase in cardiac muscle with normal size or ^ in the size of ventricle
3. Activation of neurohomoral system

Question 3

DECOMPENSATED HEART FAILURE ?

Answer 3

Failing myocardium no longer propel sufficient blood - DECOMPENSATED HEART FAILURE

Question 4

compensated heart failure?

Answer 4

If dilated ventricle meets cardiac output- compensated heart failure

Question 5

Myocardial structure changes?

Answer 5

1. Pressure overload (hypertension, valvular stenosis) - new sarcomere are added adjacent to existing sarcomere (concentric hypertrophy) - no increase in size of the heart but ventricular thickness
2. Volume overload (valvular regurgitation)- new sacromere are added in series with existing sacromere , length ^, ventricle dilates, thickness <>=

Question 6

Two types of heart failure?

Answer 6

Left and right

Question 7

Causes of Left-sided HF?

Answer 7

IHD (atherosclerosis)

SYSTEMIC HYPERTENSION

MITRAL OR AROTUC VALVE DISEASE

DISEASE OF THE MYOCARDIUM (amyloidosis)

Question 8

Effect of left sided HF

Answer 8

Reduced systemic perfusion

Elevated back pressure in the lungs

Affects heart and lungs.

Question 9

Morphology of left sided HF

Answer 9

Heart-  ventricular hypertrophic
             Mitral valve stenosis
             Myocyte hyperthrophy
             Atrial fribilation
             Interstitial fibrosis
Lungs- pressure in pulmonary veins
             Congestion and edema
             Pleural effusion
             Heavy and boggy
             Perivascular and interstitial transudates
             Alveolar edema 
             RBc extravasate from capillaries to the alveol
             Heart failure cells