Newman_HighYield Flashcards
(91 cards)
1
Q
BP =
A
CO x PVR
2
Q
constrictors?
A
NE, Epi, Ag2, TxA2
3
Q
dilators?
A
PGI2, NO
4
Q
stretch of myocardial fibers measures?
A
preload
5
Q
what are afterload determinants?
A
size of dilation of the LV
systolic BP of the LV
6
Q
what is contractility?
A
the inherent ability of the heart to contract irrespective of preload and afterload
7
Q
EF =
A
SV / LV EDV
8
Q
What is considered a good Ejection Fraction (EF)?
A
anything over 50%
9
Q
What are the 3 syndromes of coronary disease?
A
Chronic stable angina (angina pectoris)
Acute Coronary syndrome
MI
10
Q
chest pain upon exertion, think?
A
chronic stable angina
11
Q
myocardial oxygen demand is a function of what?
A
systolic BP
HR
12
Q
chest pain without exertion, think?
A
acute coronary syndrome
13
Q
what is seen on ECG with MI?
A
ST elevation
14
Q
what percentage of the coronary artery is occluded in acute coronary syndrome?
A
~80%
15
Q
what percentage of the coronary artery is occluded in MI (STEMI)?
A
100%
16
Q
what can distinguish acute coronary syndrome from MI?
A
ECG (MI has ST elevation)
17
Q
what are markers of MI?
A
CK-MB, SGOT, LDH, Troponin I
18
Q
features of a vulnerable plaque?
A
large lipid core
many inflammatory cells
low smooth muscle count
thin fibrous cap
19
Q
features of stable plaques?
A
more smooth muscle cells
well formed
20
Q
what do vulnerable plaques typically lead to?
A
acute coronary syndrome
21
Q
what do stable plaques typically lead to?
A
stable angina
22
Q
myocardial O2 supply is a function of?
A
coronary blood flow
23
Q
tx options for MI?
A
streptokinase (clot buster)
angioplasty and stent placement
bipass surgery
24
Q
what is the ideal tx for MI with ST elevation?
A
angioplasty and stent placement
25
what are the two main valvular diseases?
stenosis
| regurgitation
26
aortic regurgitation occurs during?
diastole
27
mitral regurgitation occurs during?
systole
28
what is the cardiac pathophysiological adaptation in stenosis? results from?
concentric hypertrophy (sarcomeres in parallel)
results from increased pressure
29
what is the cardiac pathophysiological adaptation in regurgitation? results from?
eccentric hypertrophy (sarcomeres in series)
results from increased volume
30
describe changes in concentric hypertrophy
increased thickness of muscle, normal volume and size
31
describe chances in eccentric hypertrophy
normal thickness, increase mass and dilation
32
what is the thickness of a normal interventricular septum?
2 cm
33
in the assessment of murmurs, what indicates stenosis? regurgitation?
turbulent flow
| inappropriate timing
34
What does Echo allow you to do?
study blood flow
| identify diseased valves
35
What are two factors involved in the assessment of stenosis?
```
the gradient (pressure drop bw LV and LA)
flow (cardiac output)
```
36
What are two main causes of mitral stenosis?
```
rheumatic fever (most common)
HTN
```
37
What are causes of mitral regurgitation?
MVP (most common)
LV dilatation
Rheumatic Fever
38
What happens to SV and EF in mitral regurg?
both increased
39
What helps distinguish acute mitral regurg from chronic mitral regurg?
lack of eccentric hypertrophy in acute
40
what are signs of aortic stenosis?
concentric hypertrophy
delayed arterial pulse (tardus)
weakened arterial pulse (parvus)
41
what 2 things are needed in IE?
bacteremia (bugs in the blood)
| diseased valve
42
complications of IE?
valve destruction
embolization
immune complex deposition
43
What is the most common cause of sudden cardiac death?
ventricular fibrillation
44
P-wave represents
depolarization of atria
45
PR interval is...
conduction through the AV node
46
Q wave
depolarization of septum
47
RS complex
depolarization of ventricles
48
ST segment
period in which the ventricles are depolarized
49
T wave
ventricular repolarization
50
if the axis of the electrode is parallel (in the same direction) to the axis of the heart: ____ deflection
positive
51
if the axis of the electrode is perpendicular to the axis of the heart: ____ deflection
no deflection, straight line
52
if the axis of the electrode is parallel and in the opposite direction to the axis of the heart: ____ deflection
negative
53
slow APs (SA and AV nodes) are driven by ___
Ca2+
54
fast APs are driven by ___
Na+
55
where is the absolute refractory period located?
bw phases 0 and 3
56
where is the relative refractory period located?
bw phases 3 and 4
57
What are the 2 common mechanisms of dysrhythmias?
altered (enhanced) automaticity
| Reentry
58
how does enhanced automaticity occur?
altered phase 4 (resting state) diastolic depolarization of the AP such that threshold potential is reached out of order/more easily
59
what factors can lead to increased automaticity?
```
autonomic (increased SNS activity)
metabolic (low O2, high CO2, low pH, inc T)
mechanical (stretch)
drugs (digitalis, NE, Epi)
electrolytes (low K, high Ca)
```
60
what 3 things does reentry need
1. contiguous pathway that forms a loop circuit
2. unidirectional block (refractory tissue)
3. slow conduction in the alternate pathway (different conduction velocity)
61
what is the most common cause of stroke?
atrial fibrillation
62
pericardial disease disrupts the elasticity of the heart during _____
diastole
63
what can cause acute pericarditis?
```
anything that causes inflammation:
infection
trauma
autoimmune (SLE)
metabolic (kidney failure, thyroid disease)
```
64
symptoms of acute pericarditis?
chest pain, worse when supine, relieved when leaning forward
65
main sign of acute pericarditis?
pericardial friction rub
66
what do you see on echo with pericardial effusion?
large clear halo surrounding heart
67
pericardial effusion leads to ____dysfunction
diastolic
68
hallmark of pericardial effusion?
all chambers have equal pressure during diastole → cardiac tamponade → EDV decreases bc the heart cannot fill up enough → C.O. decreases → BP decreases
69
hallmark of cardiac tamponade?
pulsus paradoxus
70
what is pulsus paradoxus?
exaggerated decrease in systolic BP and pulse wave amplitude during inspiration
71
what are the 2 major determinants of afterload?
size of the LV
| Systolic BP
72
what 4 drugs/classes can save lives in tx of chronic HF?
ACE inhibitors ("prils")
ARBs ("sartans")
B-Blockers ("lols")
Spironolactone (aldosterone antagonist)
73
what are the 3 neurohumoral systems activated in HF?
SNS
RAAS
natriuretic peptides
74
what are some contraindications to heart transplant?
systemic disease
| >65 age
75
define acute HF
when oxygen delivery to the heart is inadequate relative to oxygen requirement
76
most common cause of acute HF? other causes?
acute MI
exacerbation of chronic HF
post-op complication
77
if you see a low EF on exam, think?
heart failure
78
normal tissues extract around ___ % of oxygen delivered to them
25%
79
normally, about ___% of the oxygen delivered to tissues is returned to the heart
75%
80
Normal CO is ____ L/min. What happens to O2 extraction if CO decreases? Venous O2 saturation/return to heart?
5 L/min
tissue O2 extraction increases
venous O2 return decreases
81
In HF, RAAS and SNS are activated. What are the effects?
vasoconstriction of peripheral vessels (increased TPR) which maintains perfusion to the brain at the expense of decreased perfusion to kidneys (increased renin, creatinine), gut, and skin (pallor, cool extremities)
82
what measures preload?
pulmonary artery catheter
83
what are tx goals in HF?
```
raise cardiac index (CO)
raise mixed venous O2 concentration
reduce LV filling pressure (preload)
reduce TPR
maintain MAP
```
84
chronic HF is a syndrome of?
salt and water retention dictated by RAAS
85
in chronic HF, what factors affect the RAAS?
- RBF (decreased RBF increases renin)
- amount of Na+ in diet (reduced Na+ intake will reduce aldosterone levels)
- thermal stress (increased heat will increase aldosterone)
- body position (supine with elevated legs will turn off RAAS and decrease renin)
86
what ratio can differentiate bw decompensated and compensated HF?
urinary Na+:K+ ratio
| 1 in compensated
87
what are signs/symptoms of HF?
low C.O.
abnormal retention of Na and water
pulmonary congestion (crackles, orthopnea)
systemic congestion (ascites, edema, JVD)
88
dangerous side effect of ACE inhibitors?
hyperkalemia
89
how does chronic HF related to systemic disease?
- cachexia (wasting of muscles)
- increased oxidative stress
- elevated pro-inflammatory cytokines (TNFa, IL6)
90
how do you measure increased intravascular volume?
measure JVD
91
T or F: diuretics are less effective when supine
F, diuretics are more effective when supine
