Cardiology Flashcards
(91 cards)
1
Q
what three areas does RCA supply?
A
-RA -RV -LV (inferior wall)
2
Q
85% of the time, which artery gives rise to PDA (posterior descending artery)
A
RCA
3
Q
what does PDA (posterior descending artery) supply?
A
-superior interventricular septum -inferior wall
4
Q
what EKG leads correspond to PDA ischemia?
A
-ii, iii, AVF (inferior leads) ST-Elevate -reciprocal changes lateral leads (i, AVL, V5/V6); ST depression
5
Q
LMCA supplies what parts of heart?
A
-LA -LV (septal, anterior, lateral) walls -most interventricular septum
6
Q
what parts of left ventricle NOT supplied by Left
A
-SUPERIOR interventricular septum -inferior wall of LV
7
Q
SA node supplied 60% by which artery?
A
RCA
8
Q
SA node supplied 40% by which artery?
A
LAD
9
Q
AV node supplied by which two arteries?
A
-RCA -circumflex
10
Q
RCA provides what percent to AV node
A
85-90%
11
Q
which artery supplies only 10-15% of AV node?
A
circumflex
12
Q
Bundle of His supplied by WHICH two arteries
A
PDA LAD
13
Q
blood flow rate to heart is ____ mL/min?
A
250 mL/min
14
Q
what is flow to heart per min per 100grams?
A
80mL/100g/min
15
Q
what percent of CO does coronary flow take up?
A
5%
16
Q
myocardium what percentage extraction of oxygen from blood?
A
65% (this is maximum extraction)
17
Q
WHICH EKG LEAD MOST SENSITIVE FOR ISCHEMIA?
A
lead V - 75% lead II + V - 80%
18
Q
lateral EKG leads
A
I, AvL, V5, V6
19
Q
inferior EKG leads
A
II, III, AVF
20
Q
septum leads
A
V1, V2
21
Q
anterior leads
A
V3-V4
22
Q
AVR lead?
A
???? supplied by?
23
Q
what TEE view is most effective for diagnosing ischemia?
A
transgastric short axis view
24
Q
which valve is bicuspid USUALLY
A
mitral
25
normal Aortic valve area?
2.5-4.5cm^2
26
chordae tendinae on which valve?
tethers MV to papillary muscles; if rupture muscles, can have acute failure
27
normal area of MV?
4-6cm^2
28
sympathetic input to heart from WHAT ganglia of brainstem?
stellate ganglion (to both SA/AV nodes & ventricular mm)
29
cardioaccelerators at what thoracic level?
T1-4
30
Vagal input to conduction system of heart from WHICH nucleus in medulla?
nucleus ambiguous
31
transplanted heart lacks ability to do WHAT things?
-NO BARO-RECEPTOR FUNCTION (norepi has beta and alpha agonist function, increases BP and HR initially, but baroreceptor reflex to decrease HR doesn't work)
32
transplanted heart has NO what?
-no Vagal tone -no cardiac accelerators -no baroreceptor reflexes
33
changes in CARDIAC OUTPUT in transplanted heart happen by WHAT mechanism??
increase in STROKE volume
34
which sympathomimetic agents work on transplanted heart?
-amines 1) isoproterenol 2) epi 3) dopamine 4) dobutamine
35
cardiac cells attached together how?
attached by desmosomes
36
what makes striations in cardiac cells?
from linearly organized sarcomeres
37
What transmits depolarization in cardiac cells?
T-tubules - transmit depolarization
38
specialized Calcium reservoir in cardiac cells?
sarcoplasmic reticulum
39
what cell junction helps heart function as syncytium?
gap junctions
40
Cardiac MYOCYTE AP maintains plateau phase how?
inward Ca current (against concurrent K efflux); prolongs refractory period to allow mechanical contraction
41
Phase 0 of Cardiac MYOCYTE Action potential is known as WHAT phase?
-depolarization
42
Phase 0 of Cardiac MYOCYTE Action potential membrane potential change
-90 to above 0
43
Phase 0 of Cardiac MYOCYTE Action potential from WHAT ion movement?
-Na entrance thru fast VOLT-gated channels
44
Phase 1 of Cardiac MYOCYTE Action potential; what happens at BEGINNING?
-Sodium channels close -POTASSIUM CHANNELS [delayed rectifier channels] open to efflux
45
Phase 2 of Cardiac MYOCYTE Action potential also known as?
plateau phase
46
Phase 2 of Cardiac MYOCYTE Action potential; PLATEAU phase from WHAT type of channels?
L-type Ca channels
47
how much TIME between phase 0 and phase 4?
200ms
48
Phase 3 Cardiac MYOCYTE Action potential; WHAT CHANNELS CLOSE/OPEN?
-CLOSE: Ca -OPEN: K+ delayed rectifier
49
what helps trigger AP of phase 0 in myocyte?
inward Ca from phase 2/plateau phase
50
PACEMAKER cells (conducting cells) resting state at what mV?
-60mV
51
Phase 0 in PACEMAKER cells (conducting cells) is caused by WHAT ion?
Ca
52
what TYPE of CHANNELS (of ion) causes phase 0 in PACEMAKER cells (conducting cells); WHICH is primary?
-T-type Ca -L-type Ca\*\* \*\*PRIMARY, open after T-type (t-type causes slow gradual upslope of phase 4)
53
what ion creates automaticity of PACEMAKER cells (conducting cells)
Na
54
via WHAT CHANNELs does \_\_(ion)\_\_ provide automaticity
-LEAKY (i-funny) -Na channels
55
what phase(s) does PACEMAKER cells (conducting cells) NOT HAVE?
NO phase 1 NO phase 2
56
in PACEMAKER cells (conducting cells); what ion/channel provides phase 0 to phase 3 change?
iK (potassium channels)
57
nodal action potentials spread via WHAT means?
gap junctions in myocytes
58
when electrical vector of depol in direction of lead, get WHAT?
Positive deflection
59
P-R interval represents?
AV nodal delay (if any)
60
normal PR interval?
.12-.20 sec
61
normal QT?
.36-.44 sec
62
thick filament?
myosin (head groups that bind ATP)
63
thin filament
actin (monomers together)
64
regulatory proteins of myocyte sarcomere?
troponin and tropomyosin?
65
LONG filament that sits over actin binding sites
(LONG name, LONG filament) tropomyosin
66
what pulls tropomyosin out of the way? and how?
-troponin -CALCIUM binds it to allow initiation of contractile cycle
67
when powerstroke, what released?
ADP released
68
entrance of Calcium into myocytes triggers opening of WHAT other receptors?
RYANODINE receptors
69
where are Rya receptors?
on surface of sarcoplasmic reticulum
70
what to the Rya receptors do?
lflood out ca into cytoplasm (Ca-triggered-ca-release)....Ca then binds troponin
71
in order to STOP contraction cycle, how does cell get rid of Ca from cytoplasm? (2 mechanisms)
\*\*SERCA pump reaccumulates Ca in Sarco retic \*Na/Ca exchanger pumps Ca out of cell (3Na in, 1Ca out)
72
what is phospholamban (PLN)?
tonic inhibitor of SERCA pump; when phosphorylated, SERCA can work
73
WHAT is lusitropy? HOW is lusitropy related to Phospholamban and SERCA?
LUSITROPY = ability to relax --\>phosphorylation of phospholamban allows SERCA to work, which HELPS relaxation more rapidly
74
which part of brain maintains tight BP control?
-MEDULLA
75
where does medulla receive input from?
-higher cortical centers -peripheral afferents from chemo and baroreceptors
76
types of receptors ON the heart? -what neurotrans for each?
Beta1 (NE) Beta2 (NE) --------- M2 (Ach)
77
chronotropy?
HR
78
inotropy
force of contraction
79
dromotropy
velocity of conduction of A.P.
80
beta receptors are WHAT kind of receptors?
G-protein coupled
81
G-prot receptor mediation from Sympathetic nerve input changes
aden cyclase--\>cAMP--\>protein kinases PK's, increases the funny channels and T-type polarization
82
how much increase in ventricular filling from Atrial kick?
20-30% increase
83
usual process of Ventricular filling is done how? based on what pressure?
PASSIVELY; based on pressure decrease from ventricle relaxing goes BELOW atrial pressure
84
describe what's happening at each wave part
85
what happens during "a" part of atrial pressure wave?
a - the end of **A**trial contraction
86
what happens during "c" part of atrial pressure wave?
c - RV **C**ontraction, tri**C**uspid bulge
87
what happens during "x" part of atrial pressure wave?
x - atrial rela**X**ation
88
what happens during "v" part of atrial pressure wave?
v - **V**enous filling
89
what happens during "y" part of atrial pressure wave?
y - rapid empt**Y**ing of the atrium
90
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