Congestive Heart Failure (Exam III) Flashcards
What’s the 5 year mortality rate for heart failure?
50%
What is the most common cause of heart failure?
What is the progression of this disease process?
Coronary Artery Disease
CAD → Angina → MI → Scarring/Remodeling → HF
Differentiate systolic HF vs diastolic HF.
Systolic HF = reduced cardiac function (i.e. pumping)
Diastolic HF = reduced diastolic filling (usually hypertrophy)
What happens to Ejection Fraction (EF) in systolic vs diastolic failure?
Systolic HF: ↓ EF ↓ CO
Diastolic HF: ↓ CO, normal EF.
What is the rarest form of heart failure?
What 4 examples were given that can cause this heart failure?
“High-Output” Failure = normal CO, insufficient for bodily demands.
- Hyperthyroidism
- Beriberi disease
- Anemia
- Arteriovenous shunts.
How is End-Diastolic Volume (EDV) calculated?
Passive Filling + Atrial Contraction + End-Systolic Volume (ESV) = EDV
Ex. 65ml + 25ml + 50ml = 140ml EDV
How is stroke volume calculated?
EDV - ESV = SV
140ml - 60ml = 80ml
What 3 examples were given in lecture for decreasing preload?
- Na⁺ restriction
- Diuretics
- Venodilation (nitroglycerin, etc.)
Describe the pathologic positive feedback mechanism of heart failure associated with excessive afterload.
↓ CO = ↑ NE/Epi → ↑ afterload = ↓ CO
rinse and repeat
Which compensatory mechanism is the first to respond in a situation of decreased cardiac output (CO) ?
↑ Heart Rate
Which 3 mechanisms influence stroke volume?
Which of these 3 negatively affects CO?
Preload, contractility, and afterload.
↑ afterload = ↓ CO
Which pump is going to influx Ca⁺⁺ into the sarcoplasmic reticulum for storage?
SERCA (Sarcoplasmic Reticulum Ca⁺⁺ ATPase Pump)
What molecule binds to and holds Ca⁺⁺ in the sarcoplasmic reticulum?
CalS (Ca⁺⁺ Sequestrin)
In broad strokes, what is the process for Ca⁺⁺ to affect myocardial contractility?
- “Trigger” Ca⁺⁺ enters cell via action potential.
- Ca⁺⁺ binds to SR, releasing Ca⁺⁺ stores.
- Ca⁺⁺ binds w/ myosin = contraction
What 3 factors effect the amount of “trigger” Ca⁺⁺ that enters a sarcomere/myocardial cell?
- Amount of L-Type Ca⁺⁺ channels
- Duration of channel opening
- SNS stimulation.
How do β1 agonists affect trigger Ca⁺⁺ levels?
β-1 agonists ↑ time that Ca⁺⁺ L-channels are open = ↑ trigger Ca⁺ to enter the cell.