Chronic Heart Failure (CHF) Flashcards
Define heart failure
a condition where the heart is unable to adequately pump blood throughout the body
Define CHF
a condition that occurs subsequent to heart failure leading to increased pressure in the venous and capillary system
What is the result of CHF?
congestion of lungs or liver (varies with which side of the heart is affected) with blood or fluid (edema)
What is the result of heart failure?
decrease in the delivery of O2 to the body’s tissues
What happens with left-sided failure?
congestion of lungs (pulmonary edema, pleural effusion)
What happens with right-sided failure?
congestion of liver
fluid leaks into abdomen (ascities)
Is left or right sided failure more common?
left
What commonly causes right-sided failure in SAM?
HW Dz
Lab work and rads with left sided failure
- labs usually normal
- change in heart size/shape
- pulmonary edema (usually ,but not always, concentrated around the heart) and/or pleural effusion
Lab work and rads with right sided failure
- 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)
What is the initiating factor for CHF
any cardiac dz that results in decrease of cardiac output or volume of blood ejected by the ventricle
How does the nervous system respond to decreased cardiac output/decreased volume of ejected blood?
- Increases HR to attempt to increase cardiac output
2. Vasoconstriction attempts to raise systemic blood pressure
What is the event cascade that results from the NS response?
- 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
What happens if the heart can’t compensate anymore?
pressure begins to build in the circulatory system prior to the failing portion of the heart
Who is at risk for developing CHF?
any patient affected by primary cardiac Dz
Examples of congenital cardiac dz
Patent Ductus Arteriosus (PDA) Subaortic Stenosis (SAS) Pulmonic Stenosis (PS)
Examples of acquired cardiac dz
mitral valve endocardosis
mitral valve regurgitation
various cardiomyopathies
HW Dz
3 main goals of medical management for CHF
- relieve edema/pleural effusion by removing/controlling water retention and salt intake
- improve ability of heart muscle to pump adequately
- reduce worklaod of the heart
Meds to relieve edema
diuretics
- Furosemide
- Thiazide
- Potassium-sparing diuretics
Emergency drugs to improve ability of heart muscle to pump
Positive inotropes
- dobutamine
- dopamine
Meds to reduce the workload of the heart
Angiotensin Converting Enzyme (ACE) inhibitors
- Enalapril
- Benazepril
What is a potential side effect of ACE inhibitors that you need to be careful about when using them in a heart patient?
can cause hypotension and worsen the situation if severe heart failure is present
Strategy for addressing pleural effusion in cardiac patients
diuretic won’t work well for this if at all; will need to do Thoracocentesis to remove fluid from the pleural space
Things owners should know about CHF
- 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
