Exam 2 lecture 6 Flashcards

1
Q

where are the depolarizations of the heart generated

A

in the sinus node (SA node)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where is the SA node located

A

upper portion of right atrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

When depolarization is generated it is conducted across _____ to _______. What does this lead to?

A

when depolarization is generated it is conducted across INTERNODAL PATHWAY to AV NODE.

This leads to atrial contraction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

where is the AV node located

A

lower portion of right atrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Depolarization travels from AV node to _____

A

bundle of HIS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Atrial depolarization is represented by what wave

A

P wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

which phase is depolarization? WHat is the ion used?

A

Phase 0, Na current

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What ions are used in QRS complex? Which phase is it?

A

K+
Phase 1
also called ventricular depolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

early part of QRS represents______

A

ventricular depolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

PR interval is often used as a measure of what

A

AV nodal conduction time.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which drugs lengthen PR interval and slow AV nodal conduction

A

BB
diltiazem
verapamil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

QT represents

A

Ventricular repolariztion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

T waves represent

A

phase 3 repolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

PR interval represents

A

conduction time through AV node

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how to estimate HR

A

300
150
100
75
60

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

When is a PR interval considered to be too long

A

0.2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is QTc? Do men or women have longer QTc?

A

Corrected QT interval
Women have slightly longer QTc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is considered a long QTc interval? what does that lead to?

A

greater than or equal to 500 ms
increased risk of drug induced arrhythmia known as torsades de pointes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Torsades de pointes can cause sudden cardiac death T/F

20
Q

What are the 5 supraventricular arrhythmias

A

Sinus bradycardia
AV block
Sinus tachycardia
A-Fib
Supraventricular tachycardia

21
Q

What is sinus bradycardia? mechanism?

A

HR<60BPM
reduced automaticity of the SA node

22
Q

sinus bradycardia risk factors

A

MI or ischemia
abnormal sympathetic or parasympathetic tone
hyper kalemia and hypermagnesemia

23
Q

What drugs could cause sinus bradycardia

A

Digoxin
BB
CCBs
Amiodarone

24
Q

Symptoms of sinus bradycardia

A

Hypotension
Dizziness
Syncope

25
treatment of sinus bradycardia
Tx only necessary when pt is symptomatic Atropine -0.5-1 mg IV Q 5 mins
26
max dose of atropine dose
3 mg
27
Treating sinus bradycardia if unresponsive to atropine
Dopamine 5-20 mcg/kg/min Epinephrine 2-10 mcg/min or 0.1-0.5 mcg/kg/min Isoproterenol 20-60 mcg IV bolus
28
Atropine adverse effects
Tachycardia, dry mouth
29
treatment of sinus bradycardia after heart transplant and spinal cord injury
Aminophylline- 6mg/kg IV over 20-30 mins Theophylline heart transplant- 30 mg followed by oral dose of 5-10 mg/kg/day spinal cord injury- Oral dose of 5-10 mg/kg/day titrated to effect
30
long term treatment of sinus bradycardia
Permanent pacemaker
31
What can be another long term treatment if pt is unwilling to use pacemaker
theophylline oral 5-10 mg/kg/day
32
atrial activity in A-fib
Chaotic and disorganized- no atrial depolarizations
33
ventricular rate of A-fib
120-190 bpm
34
rhythm of A-fib
irregularly irregular
35
Know what the waves look like for A fib
36
P waves in A-fib
absent
37
A- fib stages
Stage 1- no A-fib (has risk factors) stage 2- pre- Afib stage 3- Atrial fibrilations Stage 4- Permanent A fib
38
explain stage 2 a fib
pre- a fib ECG findings show structural or electrical findings that dispose pt to A fib
39
What are the different stages of stage 3 A fib
3A- paroxysmal AF 3B- Persistent AF 3C- long standing persistent AF 3D- Successful AF ablation
40
explain A fib 3A
paroxysmal AF AF that is intermittent and terminates within less than 7 days of onset
41
Explain A fib 3B
Persistent AF AF that is continuous and sustains for more than 7 days and requires intervention
42
explain A fib 3C
longstanding persistent AF AF that is continous for more than 12 months in duration
43
Explain a FIB 3D
Successful AF ablation freedom from AF after intervention
44
explain stage 4 A fib
Permanent A fib no further attempts at rhythm control after discussion between patient and clinician
45
A fib mechanism
-Abnormal atrial/pulmonary vein automaticity -atrial re entry
46