Chronic Heart Failure (CHF)

Question 1

Define heart failure

Answer 1

a condition where the heart is unable to adequately pump blood throughout the body

Question 2

Define CHF

Answer 2

a condition that occurs subsequent to heart failure leading to increased pressure in the venous and capillary system

Question 3

What is the result of CHF?

Answer 3

congestion of lungs or liver (varies with which side of the heart is affected) with blood or fluid (edema)

Question 4

What is the result of heart failure?

Answer 4

decrease in the delivery of O2 to the body’s tissues

Question 5

What happens with left-sided failure?

Answer 5

congestion of lungs (pulmonary edema, pleural effusion)

Question 6

What happens with right-sided failure?

Answer 6

congestion of liver

fluid leaks into abdomen (ascities)

Question 7

Is left or right sided failure more common?

Answer 7

left

Question 8

What commonly causes right-sided failure in SAM?

Answer 8

HW Dz

Question 9

Lab work and rads with left sided failure

Answer 9

• labs usually normal
• change in heart size/shape
• pulmonary edema (usually ,but not always, concentrated around the heart) and/or pleural effusion

Question 10

Lab work and rads with right sided failure

Answer 10

• CBC mild to mod anemia if HW Dz

- Chem may show increased Alk Phos (cholestatic hepatic enzyme) and increased ALT (enzyme associated with liver damage)

Question 11

What is the initiating factor for CHF

Answer 11

any cardiac dz that results in decrease of cardiac output or volume of blood ejected by the ventricle

Question 12

How does the nervous system respond to decreased cardiac output/decreased volume of ejected blood?

Answer 12

1. Increases HR to attempt to increase cardiac output

2. Vasoconstriction attempts to raise systemic blood pressure

Question 13

What is the event cascade that results from the NS response?

Answer 13

• cardiac output and BP return to normal
• but heart has to work harder to maintain this compensation
• heart gets tired
• cardiac output and systemic BP decrease again
• body reimplements increasing HR and initiation of vasoconstriction

Question 14

What happens if the heart can’t compensate anymore?

Answer 14

pressure begins to build in the circulatory system prior to the failing portion of the heart

Question 15

Who is at risk for developing CHF?

Answer 15

any patient affected by primary cardiac Dz

Question 16

Examples of congenital cardiac dz

Answer 16

Patent Ductus Arteriosus (PDA)
Subaortic Stenosis (SAS)
Pulmonic Stenosis (PS)

Question 17

Examples of acquired cardiac dz

Answer 17

mitral valve endocardosis
mitral valve regurgitation
various cardiomyopathies
HW Dz

Question 18

3 main goals of medical management for CHF

Answer 18

1. relieve edema/pleural effusion by removing/controlling water retention and salt intake
2. improve ability of heart muscle to pump adequately
3. reduce worklaod of the heart

Question 19

Meds to relieve edema

Answer 19

diuretics

• Furosemide
• Thiazide
• Potassium-sparing diuretics

Question 20

Emergency drugs to improve ability of heart muscle to pump

Answer 20

Positive inotropes

• dobutamine
• dopamine

Question 21

Meds to reduce the workload of the heart

Answer 21

Angiotensin Converting Enzyme (ACE) inhibitors

• Enalapril
• Benazepril

Question 22

What is a potential side effect of ACE inhibitors that you need to be careful about when using them in a heart patient?

Answer 22

can cause hypotension and worsen the situation if severe heart failure is present

Question 23

Strategy for addressing pleural effusion in cardiac patients

Answer 23

diuretic won’t work well for this if at all; will need to do Thoracocentesis to remove fluid from the pleural space

Question 24

Things owners should know about CHF

Answer 24

• CHF is not the primary Dz present but is instead the result of an underlying cardiac Dz
• current status of their pet
• outline ultimate goals of therapy (short term = eliminate CS causing decreased QoL; long term = established if P responds well to Tx)
• understand meds being Rxed and why they’re needed
• therapy is life-long
• recheck appointments 3-4x a year
• many emotional ups and downs