Clasp Sudden Death Flashcards
(170 cards)
1
Q
What is central dogma?
A
how genes become protein
2
Q
What is the function of exons?
A
part of genetic code that codes for protein
3
Q
What happens to introns to make a protein?
A
have to be spliced
4
Q
What is a promotor sequence?
A
Part of genetic code that tells RNA transcriptase where to start
5
Q
What is a missense mutation
A
point mutation in which a single nucleotide change results in a codon which codes for a different amino acid
6
Q
What is a conserved gene?
A
a gene that has remained essentially unchanged through evolution- suggests its unique and essential
7
Q
How do you correct QT interval for HR?
A
QT interval/ (square root of R-R)
8
Q
What cardiac arrhythmia is classically associated with long QT syndrome?
A
torsades de pointes
9
Q
What is the defining characteristic of ventricular tachycardia?
A
QRS complex is greater than 120ms
10
Q
What drug class is used in the treatment of long QT syndrome?
A
beta blockers
11
Q
What is shock?
A
inadequate organ perfusion leading to inadequate oxygen delivery to tissues and eventually organ failure
12
Q
What are the 5 types of shock?
A
hypovolaemic; cardiogenic; septic; anaphylactic and neurogenic
13
Q
What is the most common infection to cause septic shock?
A
gram positive bacterial infection
14
Q
What are examples of causes of neurogenic shock?
A
spinal cord injury; spinal anaesthesia
15
Q
What are the common signs of shock?
A
tachycardia; hypoxia; tachypnoea; increased capillary refill time; decreased UO; pallor; cold
16
Q
What is Frank Starling’s Law?
A
increasing end diastolic volume eg preload increased the cardiac output
17
Q
What is afterload?
A
resistance LV must overcome to circulate blood
18
Q
What are the two equations for CO?
A
CO=HRxSV; CO=MAP/SVR
19
Q
What is oxygen delivery (DO2) equal to?
A
CO x CaO2
20
Q
What makes up arterial oxygen content?
A
o2 with haemoglobin and dissolved o2
21
Q
What is the pathogenesis of anaphylactic shock?
A
sensitised mast cells have IgE on surface which allergen binds to, causing mast cell degranulation and release of inflam mediators eg histamine and PGs, histamine activate H1 receptors on endothelium making hte vessels leaky
22
Q
How does adrenalide counteract anaphylaxis?
A
binds to adrenergic receptors on endothelium to close up leaks which reverses process of anaphylaxis
23
Q
What are the features of cardiogenic shock?
A
pulmonary oedema and hypotension
24
Q
What is the key issue in cardiogenic shock?
A
heart failure
25
What is the key issue in neurogenic shock?
loss of sympathetic outflow in thoracic spine
26
What is sepsis 6?
```
Blood cultures
Urine output
Fluid challenge
Antibiotics
Lactate
Oxygen
```
27
What are the reversible causes of cardiac arrest?
hypovolaemia; hypoxia; hypothermia; metabolic causes; tension pneumo; cardiac tamponade; toxin and thrombus
28
What heart rhythms is immediate defibrillation appropriate for?
VF and pulseless VT
29
What is the pathophysiological process underlying cardiac arrest with hypovolaemia?
inadequate stroke volume to maintain cardiac output
30
What is the pathophysiological process underlying cardiac arrest with hypoxia?
lack of oxygen at amitochondrial level in the myocytes
31
What is the pathophysiological process underlying cardiac arrest with hypothermia?
slows metabolic activity until enzymes stop functioning
32
What is the pathophysiological process underlying cardiac arrest with metabolic causes?
destroys electro-chemical balance across cell membrane
33
What is the pathophysiological process underlying cardiac arrest with tension pneumo?
greater pressure in pleural cavity then in lung squashes the lung
34
What is the pathophysiological process underlying cardiac arrest with tamponade?
myocardium squashed by pericardial fluid
35
What is the pathophysiological process underlying cardiac arrest with thrombus?
clot in lungs/coronary vessels preventing flow
36
What is the treatment for cardiac arrest caused by hypoxia?
oxygen and atropine
37
What is atropine?
a muscarinic receptor antagonist
38
What is cardiac arrest?
cardiac output is not sufficient for a palpable carotid pulse
39
What drugs are used in cardiogenic shock?
inotropes eg dobutamine, milnarone
40
What are the indicators of severe sepsis?
tachypnoea >=22; hypotension systolic <100mmHg; altered mental status
41
What are the 3 important types of thrombus causing cardiac arrest?
PE; atherosclerotic plaque; amniotic fluid embolism
42
What is the time for clinical death to biologic death under normal temp?
3-6mins
43
What is the difference between biologic death and clinical death?
clinical death is a reversible state
44
What is the most common cause ofcardiac arrest?
coronary heart disease
45
How often should adrenaline be given in ALS?
every 3-5mins
46
When should amiodarone be given in ALS?
after 3 shocks
47
How deep should cardiac compression be?
5-6cm
48
How many cardiac compressions be done?
100-120/min
49
Why should you not lean whilst doing CPR?
to ensure recoil without losing contact between hands and sternum
50
What can be used to meausre CPR in real time?
waveform capnography
51
What are the non-shockable rhythms?
PEA and asystole
52
What are the features of VF?
bizarre irregular waveform; no recognisable QRS complexes; random freq and amplitude
53
What are the causes of transthoracic impedenace?
electrode size; distance between electrodes; size of chest; hairy chest; poor electrode contact; air trapping
54
What are the features of monomorphic VT?
broad compex rhythm; rapid rate; constant QRS morphology
55
What are the clinical signs of a tension penumo?
decreased breath sounds; hyper-resonant percussion note; tracheal deviation
56
When should cardiac tamponade be considered as a diagnosis?
penetrating chest trauma or after cardiac surgery
57
what is the immediate post cardiac arrest treatment?
use ABCDE approach; aim for SpO2 of 94-98; normal PaCO2; ECG; treat cause
58
How long is seconds in one big box on ECG?
0.2s
59
How long is a small box on ECG?
0.04s
60
How is HR calculated from ECG?
300/large squares of R-R
61
What is the normal length of the PR interval?
0.12-0.2s
62
What is the normal QRS complex interval?
<120ms
63
How long should QT interval be?
<0.44s - F; <0.4s in M
64
What suggests a risk of asystole with bradycardia?
recent asystole; Mobitz II AV block; complete heart block with broad QRS; ventricular pause >3s
65
What is bradycardia often associated with?
shock; syncope; myocardial ischaemia; heart failure
66
what is the first line treatment for bradycardia
atropine
67
What is classic picture seen on ECG with atrial flutter?
saw tooth
68
What is the difference between atrial flutter and atrial fibrillation?
atrial flutter the atria beat regularly and more often than the ventricles whereas AF is irregular and produced in the pulmonary veins not atria
69
What are the features of AF on ECG?
irregularly irregular QRS; no p waves
70
What is typical atrial rate in AF?
>350bpm
71
What are the features of ventricular tachycardia on ECG?
regular, wide bizarre QRS
72
What are the features of torsades de pointes on ECG?
200-250bpm; regular or irregular; sinusoidal pattern; twisting of axis
73
What is torsades de pointes typically associated with?
electrolyte abnormalities
74
What is the definition of first degree AV block?
regular prolonged PR interval >0.2s
75
What are the features of type 1 Mobitz?
regularly irregular; increased PR interval until dropped beat then cycle starts over
76
What are the features of Mobitz second degree?
some p waves not conducted but p waves usually regular and same PR interval for all conducted beats
77
What are the features of complete heart block on ECG?
regular p waves and regular QRS complexes but no relationship between them
78
What channel do class I anti-arrhythmic drugs target?
sodium channels
79
What do class II anti-arrhymic drugs target?
beta-adrenoceptor antagonists- beta blockers
80
What do class III anti-arrhythmic drugs target?
potassium channels
81
What do class 4 anti-arrhythmic drugs target?
calcium channels
82
Which classes of anti-arrhythmics are involved in rate control?
classes II and IV
83
Waht classes of anti-arrhythmics are invovled in rhythm control?
class I and III
84
What is the mechanism of action of adenosine?
opens potassium channels in the AV node
85
What is the MOA of digoxin?
stimulates vagal activity- slows conduction and prolongs refractory period in AV ndoe and bundle of His
86
Give an example of type 1a agents?
disopyramide and procainamide
87
give an example of a type Ib agent?
lignocaine
88
Give an example of a type Ic agent?
flecainide
89
Give examples of type III agents?
amiodarone and sotolol
90
When do afterdepolarisations occur?
during phase 3 or 4 of an AP
91
When are afterdepolarisations more likley to occur?
when the AP duration is abnormally long
92
When do early afterdepolarisations occur?
during late phase 2 or 3
93
When do delayed afterdepolarisations occur?
late phase 3 or early phase 4
94
What arrythmia is asssociated with early afterdepolarisations?
torsades de pointes
95
What is the most common mutation causing long QT syndrome?
KCNQ1- potassium channel
96
What arrhythmia is associated with long QT syndrome?
torsades de pointes
97
What is the difficulty with diagnosing long AT syndrome?
no set length of QT so where is the line drawn- but, as length increases. risk of SCD increases
98
What is the most common mutation associated iwth Brugada syndrome?
SCN5A-15%: most patietns do not have an ideentified mutation
99
What is isolated LQT known as?
Romano-Ward Syndrome
100
What is the LQT associated with deafness known as?
Jerrell Lange-Neilson syndrome
101
What happens in torsades de pointes?
normal SA beat and the abnormal beat lands when half of heart is refractory and half is ready so ready half receives beat then it passes to the other half which is now ready and etc.
102
What is LQTS defined as?
QTc >=480ms in repeated ECGs
103
What are the common triggers for SCD in LQTS?
sleep; stress and exercise
104
Why is congenital short QT syndrome rarely seen?
not compatible with life- usually die in utero or as baby
105
What channels are affected in short QT syndrome?
potassium channels
106
What is seen on ECG with Brugada syndrome?
ST elevation and RBBB in V1-3
107
What common arrhythmia is associated with Brugada syndrome?
AF
108
What arrthmias are pts with Brugada syndrome at risk of?
AF; torsades; VF
109
Why is it difficult to diagnose Brugada syndrome?
intermittnet and changeble ECG changes
110
What is the problme channel in Brugada syndrome?
sodium channels
111
What are the triggers for ECG changes in Brugada syndrome?
stress esp. fever; flecainide- blocks sodium channels
112
How is brugada syndrome inherited?
AD
113
Which sex is brugada syndrome more common in?
males x8
114
What is catecholaminergic polymoprhic VT?
adrenaline induced (exaggerated reaction to normal levels of adrenaline) bidirectional VT
115
How is catecholaminergic polymorphic VT inherited?
AD
116
What is the treatment for catecholaminergic polymorphic VT?
beta blockers; felcainide; sympathetic denervation surgery
117
What is the problem in Wolff-Parkinson White syndrome?
accessory pathway between atria and ventricles
118
Waht is needed to diagnosed WPW syndrome?
palpitations and ECG appearnace
119
What is a delta wave?
slurred upstroke into QRS; delayed onset into QRS
120
Waht is seen on ECG with WPW syndrome?
delta waves and short PR interval
121
What is the most common arrhthmia with WPW syndrome?
atrioventricular reentrant tachycardia- SVT
122
What is the most common mutation in hypertrophic cardiomyopathy?
sarcomere genes
123
What is the risk of mortality with HCM?
1% per year risk of mortality
124
How do you determine whether to give an ICD to HCM patients?
HCM risk calculator
125
What is affected in dilated cardiomyopathy?
sarcomeres and desmosomes
126
What is the RF for developing dilated cardiomyopathy?
alcohol
127
Which gender gets dilated cardiomyopathy more commonly?
males
128
What happens in arrhythmogenic right ventricular cardiomyopathy?
fibro-fatty replacement of cardiomyocytes- loss of heart structure and change in conduction
129
What increases your isk of SCD with arrhythmogenic RV cardiomyopathy?
FHx of premature SCD; secerity of RV and LV function; ECG- QRS prolongation; male, older at presentation
130
What drug is particularly useful in arrhythmogenic RV cardiomyopathy?
sotalol- has some class III anti-arrhytmic action
131
What is the significance of an intronic variant?
low likelihood of effect
132
What is the significance of a mutation of the edge of an exon?
splicing error
133
What is the significance of an exonic variant?
1- change amino acid
2- create stop codon
3- cause frameshift
4- have no effect
134
What does cDNA stand for?
complementary DNA
135
What is cDNA?
essentialy mature mRNA sequence with introns removed
136
What is Loeys Dietz syndrome associated with?
bifid uvula; down-slanting eyes and aortic aneurysms
137
Above which grading intensity of heart murmurs are thrills present?
4/6
138
When is JVP raised?
if >4cm above sternal angle
139
What is a positive abdominojugular reflex?
JVP is raised through 15s compression
140
What does a positive abdominojugular reflex mean?
RV failure
141
What is the treatmnet for native valve indolent endocarditis?
amoxicillin and gentamicin
142
What is the main bug associated with native valve indolent endocarditis?
strep. viridans
143
what is the treatment for acute native valve endocarditis?
fluclox
144
What is the main bug associated with native valve acute endocarditis?
s. aureus
145
What is the treatment for prosthetic vlave of MRSA endocarditis?
vancomycin, rifampicin and gent
146
What are roth spots?
boat-shaped retinal haemorrhage with pale centre
147
What vessel is ST elevation in V2-V4 assocaited with?
diagnoal branch of LAD
148
What vessel is ST elevation in V1 and V2 assocatied iwth?
septal branch of LAD
149
what vessel is ST elevation in V1-6 associated iwth?
LCA
150
What vessel is ST elevation in I, AvL, V5 and V6 associated iwth?
circumflex branch of LCA
151
What vessel is ST elevation in II, III and aVF associated iwth?
RCA
152
What is first line tx for SVT?
vagal manoeuvres
153
what is 2nd line for SVT?
adenosine
154
What is 3rd line for SVT?
beta blocker
155
What paitnets is adenosine CI in?
asthma
156
What should be used instead of adenosine in asthmatics?
verapamil
157
What is used for pharma cardioversion with AF/flutter?
flecainide
158
what should be used with structural heart damage in pharm cardioversion with AF/flutter?
amiodarone
159
What is the treatment for sustained VT?
amiodarone
160
What is hte treatment for torsades?
magnesium sulphate
161
What is the treatment for bradycardia?
atropine
162
Which korotkoff sound is systolic pressure?
phase 1
163
Which korotkoff sound in diastolic pressure
phase 5
164
What is the mnemonic for classses of antiarrhythmics?
South Beach Polka
165
What is the difference between the dihydropyridines and non-dihydropiridines?
dihydropirimidines work only on vascular smooth muscle, whereas non- heart and vascular
166
What does hepb surface antigen mean?
infected with hep b -acute or chronic
167
what does hep b surface antibody ?
devloped immunity to hep b- natural or vaccinr
168
What does HBeAg mean?
virus is multiplying
169
What does hep b core antibody mean?
person has been infected with hep b-dont get with vaccine
170
What does IgM anti-Hbc mean?
acute infection
