Heart Failure Flashcards
Define low output heart failure / “Forward” HF
ventricular dysfunction resulting in poor tissue perfusion (↓ CO) & arterial hypotension (↓ BP)
Define CHF / “Backwards” HF
cardiac malfunction resulting in ↑ pulmonary venous or systemic venous pressures
Which usually precedes the other: low output heart failure or congestive heart failure
CHF almost always precedes low output HF
What is the expected blood pressure (High vs Low vs Normal) for the following:
congestive heart failure:
low output heart failure:
congestive heart failure: normal BP
low output heart failure: ↓ BP
True or False: patients with CHF usually appear BAR, whereas patients with low output heart failure appear QAR
TRUE
BP = _____ X _____
BP = CO x SV
List the harmful effects of Angiotensin II
- Free radicals cause cell death and fibrosis resulting in myocardial dysfunction (can’t fill or contract)
- Increased vasoconstriction causes increased afterload and decreased SV and CO
List the beneficial effects of Angiotensin II
- Increased vasoconstriction and sympathetic tone results in increased BP and increased CO
- Triggers aldosterone to increase Na+ and H20 which increases blood volume and CO
In concentric hypertrophy, sarcomeres are added in __________
parallel
In eccentric hypertrophy, sarcomeres are added in __________
series
What symptoms and CS do you expect to see with L-sided CHF?
- Syncope
- Coughing (Dogs>cats)
- Hypoxemia (dec. gas exchange from lungs)
- Exercise intolerance
- Tachypnea (inc resp rate) to try and compensate/ Dyspnea
- Pulmonary edema
Cats: pleural effusion causing ABD distention
What symptoms and CS do you expect to see with R-sided CHF?
- ABD and jugular distention
- Exercise intolerance
- Cough (Dogs>cats)
- Tachypnea/Dyspnea
- Syncope
- Diarrhea if peritoneal effusion
PE abnormalities in a dog with L-sided CHF?
- Tachypnea/Dyspnea
- Inc HR (tachycardia)
- Crackles/wheezes
- Muscle loss
- Abnormal heart sounds
PE abnormalities in a dog with R-sided CHF?
- Inc HR (tachycardia)
- Jug vein distension
- +/- Tachypnea/Dyspnea if pleural effusion
- Decreased or absent lung sounds if pleural effusion
- ABD distension due to peritoneal effusion
- Abnormal heart sounds
PE abnormalities in a cat with R-sided CHF?
- Inc HR (tachycardia)
- Jug vein distension
- Tachypnea/Dyspnea due to pleural effusion
- Decreased or absent lung sounds due to pleural effusion
- +/- ABD distension due to peritoneal effusion
PE abnormalities in a cat with L-sided CHF?
- Tachypnea/ +/-Dyspnea
- Inc HR (tachycardia)
- Increased bronchovesicular sounds/Crackles/wheezes if pulmonary edema ORRR decreased/absent lung sounds if pleural effusion
- Muscle loss
- Abnormal heart sounds
CS and PE abnormalities of Low Output heart failure
- Pale mucous membranes
- Hypothermia
- Weak femoral pulses
- Weakness/collapse
- Tachycardia (inc HR)
- Abnormal heart sounds
- Muscle loss
(Bolded shows differences between low output heart failure vs CHF)
List 2 tests you would want to do in order to diagnoses low output heart failure?
- Blood pressure (will be LOW)
- Lactate (will be HIGH due to hypoxemia and anaerobic metabolism)
3 Goals of heart failure therapy?
- Relieve congestion
- Improve cardiac output
- Prevent progression
The first step of HF therapy is to relieve congestion. How is this done?
Decrease ventricular filling pressure by:
- Decreasing blood volume (preload): Give diuretic drug to dec. preload
- Decrease venous return to the heart (preload): Give venodilating drugs
- Increase forward flow (CO)
Which drug is given during heart failure therapy to decrease preload?
Furosemide!!! (loop diuretic)
- decreases blood volume back to the heart which slows down accumulation and congestion
Which drugs is given during heart failure therapy to improve CO and relieve congestion in the case of a systolic dysfunction?
- Positive inotrope to increase ventricular contractility (Ex: Pimobendan, Dobutamine)
- Arterial dilating drugs to decrease afterload
Which drug is given during heart failure therapy to improve CO and relieve congestion in the case of a diastolic dysfunction?
- Negative chronotropic drugs to decrease HR and allow more time for filling
- Lusitropic drugs to improve ventricular relaxation and atrial function
The 3rd step of HF therapy is to prevent progression/remodeling. How is this done?
- Inhibit the deleterious neuroendocrine mechanisms (Ex: RAAS and Ang II)
Give ACE inhibitor!! Benazepril/Enalapril