Week 1 Flashcards
Name a painfull lesions seen on the extremities related to an infectious heart disease, then name that disease
Oslers nodes, a type III hypersensitivity, seen in infectious endocarditis
The major and minor duke criteria. And what disease are they for?
Major:
- Multiple positive blood cultures
- Evidence of endocardial involvement (mitral or av regurg)
Minor:
- Predisposition (heart valve, iv drug use)
- Fever above 38c
- Vascular phenomenon (arterial emboli, janeway lesions, however you word it basically peripheral petechiae)
- Immunologic phenomenon (oslers nodes, roth spots, rheumatoid factor)
- Single blood culture
In what group and how hemolytic is strep pyo
Group a beta hemolytic
Most common cause of myocarditis
Coxsackie B
Adenovirus
White spots on the retina. What are they called and what disease do you see them in?
Roth spots, seen in endocarditis
2 most common alpha hemolytic strep species
Strep pneumo and viridians
What holds the cardiac cells together, and also allows action potentials to pass through them? What is the name of the protein that forms these structures?
Gap junctions, connexin
What structure between myocytes ensures the mechanical transfer of energy between them?
Fascia adherens and macula adherens
Aka desmosomes
Desribe how the pns slows the heart rate
Vagus nerve releases ach on the SA node, which:
- Increases the permeability of the resting membrane to K, allowing the cell to hyperpolarize
- decreases the current of the funny channels, so they depolarize more slowely
what do you call a compression of the heart caused by fluid in the pericardium
cardiac tamponade
The arterial branch that supplies the SA node comes off of which coronary artery
Right Coronary artery in 60 percent of people
coronary occlusion is most common in this artery
left anterior descending (aka anterior interventricular branch)
What does coronary arterial dominance refer to?
what are the ratios?
which artery gives rise to the posterior interventricular artery
70 % right coronary artery
10% left coronary artery (widow maker)
20% co-dominant
where is the great cardiac vain on the heart
curves around the left from the sinus and goes with the LAD artery
what is the name of the small outcropped pouch in the left atrium and what muscles are there?
Left auricle, pectinate muscles
circumflex artery comes off what
left coronary
path of sympathetic nerves that act on the heart
and what they release
preganglionic fibers from upper 4 or 5 thoracic spinal segments
synapse in cervical and upper thoracic sympathetic ganglia of sympathetic truck
terminate in SA node and AV node to increase contraction of heart and dilation of coronary arteries.
release NE
Path of the parasympathetic nerves from the CNS to the heart and what they release
preganglionic from the vagus
pass through cardiac plexus without synapsing
synapse onto postganglionic neurons in microganglia in the walls of the atria\
release Ach
Three waves of the right atrium on a pressure vs time graph
A wave: atrial contraction
C wave: bulging of tricuspid valve into right atrium die to ventricular contraction
V wave: right atrium and central veins re-filling behind closed tricuspid valve
describe the mechanism of S2 splitting
When you breath in, you create a drop in pressure in the thoracic cavity. This vaccuum sucks blood from the vena cavas (more so that the pulminary veins) and causes increased preload in the right ventricle, which as a result, closes later than the aortic (this vacuum also causes blood to stay in the lung longer, so there is less filling of the left ventricle)
Does increased preload increase the end diastolic volume?
yes.
two ways to measure the Mean Arterial Pressure
DP + 1/3 PP (pulse pressure)
or
2/3 DP + 1/3 SP
equation for ejection fraction
stroke volume / peak volume
Effect of NE on the heart
there are 5 main ones
Increases HR by activating funny channel currents (positive chronotropic effect)
Increases rate of action potential conduction, particularly in AV node by altering conductivity of gap junctions (positive dromotropic effect)
increases the amount that the muscle fibers can contract by activating Ca current and increasing Ca release from the SR (positive inotropic effect)
increase in the rate of cardiac relaxation by increasing Ca reuptake by the SR (positive lusitropic effect)
Decrease in cardiac action potential duration, which promotes realy relaxation via early activation of delayed K current (positive lusitropic effect)
what is the law that says that cardiac output increaces with preload volume?
starlings law