Flashcards in L28 Deck (21)
2 types of HF
HFpEF = systolic dysfxn
HFrEF = diastolic dysfxn
Same clinical presentation: orthopnea, PND, DOE, peripheral edema
What is low EF
EF = SV/EDV
= amt out / total filling amt
What does systolic vs diastolic dysfxn mean for HF?
Diastolic dysfxn = inadequate LV filling at normal pressures
Systolic dysfxn = inadequate LV ejection
What are 3 reasons you might not be filling LV completely - HFpEF
1. LV hypertrophy - excessive muscle means ↓compliance
2. CAD --> ischemia = stiffer
3. Restrictive cardiomyopathy
What is restrictive cardiomyopathy? How does this look on ECHO?
Tissue invading myocardium that change the muscle properties (compliance)
See bilateral atrial dilation - small ventricles w/ huge atrial
What does ↓LV compliance (filling) lead to? 2 things:
1. ↑LV EDP
What does ↑LV EDP lead to?
pEF or rEF - more common in:
- Older pts
Compensation for ↓CO w/ HF
1. ↑renin - AGT2 - aldosterone = volume expansion
2. ↓baroreceptor firing -> ↑sympa tone (↑NE) -> ↑contractility
GOAL = ↑afterload & HR to restore CO
Why do HF pts get peripheral and pulm edema?
Overcompensation with RAAS
The Law of LaPlace says that LV wall stress equals
LV wall stress = (LV radius x LV pressure) / 2x LV thickness
A dilated LV w/ thin walls = high wall stress
- Hypertrophy to ↓that stress
pEF or rEF - treat with med
Which meds improve survival of rEF pts
Which med improve symptoms of rEF pts
Why give vasodilators
- Better LV ejection = ↑SV
NO change contractility
Caution about spironolactone
Which pt populations respond bet to hyrdalazine nitrates?
Why put in an internal cardioverter defribrilators
= Biventricular pacing
For HFrEF only
Should you put HFpEFs on diuretics?
Sure! Also have compensatory volume overload and diuretics not a part of neuro-hormonal axis that rEF pts don't respond to