(12) Flashcards
so what can you do to make effort smaller - get a bigger hand
(The LAw of Laplace)
- the bigger the LV, the greater the what?
- At any radius (LV size), the greater the systolic P developed the greater the what
- increased wall stress requires what?
- how does heart deal with increased wall stress?
- wall stress
- wall stress
- increase O2 uptake (greater rate of ATP use)
- hypertrophy (creates more sarcomeres)
(Cardiac Hypertrophy)
(influenced by type of chronic load)
- increase systolic pressure (pressure overload) results in what kind of hypertrophy?
- increased volume load (volume overload) results in what kind of hypertrophy?
- new sarcomeres in parallel (concentric)
- new sacromere in series (eccentric)
(determinants of ventricular filling)
- what of the myocardium?
- ventricular what?
- venous what?
- duration of what?
- atrial what?
- active relaxation of the myocardium
- ventricular compliance
- venous return
- diastole
- atrial contraction
(she didn’t talk about this figure too much)
(Some people say - the ventricle sucks)
- relaxation is due to active removal of what?
- When AV valves open, the ventricle is doing what?
- During the initial filling the ventricles aspirates some blood from where?
- Ca from the cytoplasm surrounding the myofibrils
- actively relaxing
- the atrium (ie the ventricle sucks blood in)
(Diastolic Function)
- what determines degree of diastolic function?
- decreased compliance –> what?
- ventricular compliance
- increased stiffness (stiffness (1/compliance) is ratio of dP/dV
(then look at graph - she talked about this a bit)
(Ventricular compliance)
depends on
- vascluar dimensions - smaller ventricles are stiffer or no?
- wall thickness - thick walls stiffer?
- Muscle activity - incomplete relaxation –> ?
- wall composition - fibrosis –> ?
- external compression - impairs what?
- stiffer
- yep (LV is stiffer than RV)
- increased ventricular wall stiffness
- increased stiffness
- normal diastolic expansion
(Diastolic Function)
- increase vasular stiffness impairs what?
- baseline of PV loop rises more steeply –> ?
- Stiffer heart may be where on the Starling curve?
- normal pump function
- increased atrial P needed for filling
- lower (smaller end diastolic volume)
(Coronary Circulation)
(Myocardial Oxygen Delivery)
- coronary arteries control what?
- Flow rate determines delivery of O2 - flow equal what? Is resistance relatively constant?
- Coronary blood is very deoxygenated -
FUCK IT - just read this slide
- myocardial O2 supply
- (AoP - RAP)/R; don’t know…
(Coronary Microcirculation)
(very rich capillary supply to heart)
she’s really speeding through these… just read it again
and this one
(Coronary blood flow)
- proportional to the driving pressure across the coronary bed/ what? driving pressure equals what?
- Varies during cardiac cycle; what in diastole? in systole?
- Early diastolic flow (peak flow rate) can be impaired when what occurs?
- resistance; AoP - RAP (or coronary sinus P)
- 85%; remaining 15% (but only in epicardial areas)
- when rate of myocardial relaxation in early diastole is slowed
- Since flow goes from epicardial–>endocardial, ischemia first occurs in what?
- subendocardium
- anything that causes heart to be thicker than normal
she then talked about nemo a bit at around 35 if you feel like watching it…
look at this
know the difference between cardiac factors and coupling factors