Arrhythmias Flashcards
(126 cards)
1
Q
Time course of VPCs from birth to adults
A
Commonly occur in infancy.; declines in incidence in early childhood
Becomes common again in adolescence and adulthood
2
Q
Ventriculophasic Sinus arrhythmias
A
The 2 p waves sorrounding a QRS occurs at a faster rate
Exact reason not known
?increased SA nodal artery flow
3
Q
How to identify a WPW with long refractory period
A
Intermittent loss of delta ; at rest or exercise or with procainamide
Chances of Afib with fast conduction less
4
Q
First step in Arruda algorithm For WPW
A
Two leads V1& Ld 1 Ld 1::Isoelectric or neg DELTA-Left free wall path OR V1::R/S more than 1-Left free wall
To locate more precisely check DELTA in
aVF-positive::LL/LAL
Negative::LP/LPL
5
Q
Most common type of WPW
A
LEFT LATERAL
6
Q
Second step in Arruda for WPW
A
Coronary Sinus step
Negative DELTA in Ld II ( mimics IWMI)
7
Q
SVT originates from
A
HIS bundle and above
8
Q
Cardiac compromise happens when heart rate is more than
A
200/mt i.e. < 300 ms
60000ms/300ms=200
9
Q
Atypical AVNRT is precipitated by —-ectopics
A
Ventricular
10
Q
Long RP tachy means
A
RP> PR
11
Q
Irregular SVT
A
AF,MAT,AFlutter with varying condxn
12
Q
Atrial tachy is Short or Long RP
A
Usually Long RP. Or if Short RP , the short RP >90 ms
13
Q
Epicardium mapping in VT is indicated in structural diseases like
A
CHAGAS
ARVD
14
Q
Frequent VPCs definition
A
- More than 60/ hour or 1/minute -ESC cardiology
2. >1% or > 1000 per day- Korean heart journal
15
Q
ECG findings which suggest Brugada syndrome in an asymptomatic type 1 pattern
A
1.First degree heart block
2.Left axis deviation
Late potential in SAE,
3. Afib
4. ST/T alternans with VPCs of LBBB morphology in Holter
5. Fragmented QRS
BLAST Fragmented the QRS
2013 Criteria for Asymptomatic Pts
16
Q
Use of family history in diagnosis of BRUGADA SYNDROME
A
- Family history of SCD <45 yrs
2. Type 1 ECG pattern in family - This was there in 2005 criteria but removed in 2013 criteria
17
Q
In pts with WPW and AF higher risk is suggested by persistence of accessory pathway conduction with RR intervals
A
Less than 250ms
18
Q
SCD in apparently normal hearts incidence
A
5-20%
19
Q
In Lowns grading of VPB Ron T is
A
Grade 5 . Most severe
20
Q
Lowns grading of Multifocsl VPBs
A
Grade3
21
Q
Lowns grading of couplets and NSVT
A
Grade 4
22
Q
Location of carotid Sinus is b/w
A
Angle of mandible and Superior border of Thyroid cartilage
23
Q
What direction of current do V1/2 measure
A
Anterior/Posterior forces
24
Q
Right/Left forces are measured by which leads
A
V6, Lead I
25
If all frontal plane leads are isoelectric the axis is
Cannot be determined i.e. Indeterminate.. This is a normal variant
26
Antidote of adenosine
Aminophylline
27
Location of carotid Sinus
Inferior to angle of mandible at level of Thyroid cartilage
28
ACC/AHA/HRS definition of Non valvular Afib 2014 Jan
In the absence of
1. Rheumatic MITRAL VALVE DISEASE
2. Mitral valve repair
3. Prosthetic valve
29
AV Search hysteresis is
AV delay is periodically lengthened for upto 8 consecutive beats to search for intrinsic PR intervals
Useful for pts with intermittent AV block
30
MVP mode of pacing
Managed Ventricular Pacing
Uses AV Search hysteresis
31
Primary mode of Pacing in MVP Mode is
AAIR
32
Heart rate is said to be regular if the RR variability is
Less than 60 ms
Internet
33
Step 3 if Arruda algorithm (Septal step)
V1 lead negative or equiphasic delta
aVF -positive means AS or MS . (anteroseptal or mid septal ) if axis >0 AS & if < 0 MS
Now remaining is PS( posteroseptal)- if aVF delta is equiphasic it is LPS; if negative it is RPS
After this step the remaining will be Right free wall
34
WQRS tachy showing indeterminate axis but not VT occurs in setting of
WPW with antidromic conduction
Bi ventricular pacing- shows a q in Ld I
35
An axis change of ______indicates VT
40 degree
36
An axis of ____ with RBBB indicates VT
-30 or more
37
An axis of _____indicates VT in LBBB
90 or more
38
A QRS duration of> ______ indicates VT in RBBB
140
In LBBB it is 160
39
How to differentiate WPW(antidromic) vs VT
Check V4,5,6-- If predominantly negative VT
If not check for q in V2,3,4,5,6 - if present VT
If not look for 1:1 conduction- if present not VT
40
3 features of AV dissociation in VT
1. Dissociated p waves
2. Fusion beats
3. Capture beats
41
Morphological criteria in V6 for VT with RBBB
rS in V6 . s/o VT
If R/s is more than 1 it's SVT
42
Morphological criteria for VT with LBBB in V6
qR pattern in V6
43
Anterior fascicle supplies which part of LV
ALU--Anterior supplies LATERAL and UPPER parts
44
Short QT syndrome QT interval
360 or less
45
How to evaluate Short QT syndrome
330 ms or greater & no clinical criteria- no evaluation
Less than 330 (Markedly short QT)and no clinical criteria- EP reference for genetic screening etc
<350 and clinical criteria need ICD
Clinical-VT,Syncope, AF , Family history etc
46
MC type of LQTS
Type 1
Deafness is a feature
47
Triggers for LQTS
LQTS1- Exercise
| LQTS2- Loud noise
48
Pause dependence in LQTS means
Ectopic-Pause-next QT will be prolonged- now if another ectopic happens Torsades is ppted
Long -Short cycle
Common in LQTS2
49
Paroxysmal Afib means
Reverts in 7 days
50
Main risk of sub clinical Hyperthyroidism
Afib
51
VKA was proven superior to Aspirin for stroke prevention in AF in
1995
52
VKA was shown to reduce stroke in Afib by 2/3 rd versus placebo in
2000
53
Dabigatran in Afib trial was published in
2009
54
Around .....% of patients with Afib have concomitant ACS
10
55
Donperidone should not be prescribed if QTc is more than
Males 450
| Females 470
56
Most common cause of cardiac arrest in young adults
1. HCM
| 2. Anomalous origin of Coronary Arteries
57
Castle AF trial results
In AF and EF <=35NYHA II or more with CRT— Catheter ablation superior to Drugs
58
Average heart rate in Inappropriate Sinus Tachy in 24 hr Holter
> 95
Other sources> 90/my
59
Effect of beta blockers in IST ( inappropriate Sinus tachy)
Generally ineffective even in high doses.
Can try Ivabradine also
60
POTS (postural orthostatic tachycardia syndrome)
Persistent increase in heart rate by >30 beats/mt or HR > 120/ mt within 10 mts of upright position without orthostatic hypotension
61
P waves may be difficult to see when HR is more than
140
62
Agent for acute treatment of SVT in pregnancy
Adenosine
2nd Metoprolol
3rd Verapamil
4th Procainamide
5th Amiodarone when no other options .Multiple adverse effects on fetus
63
Role of eyeball pressure in SVT
Abandoned - dangerous
64
Cardioversion in pregnancy
Reported to be safe in all stages of pregnancy
2015 ACC/AHA. SVT Guidelines
65
Ongoing treatment of SVT in pregnancy
Digoxin, Metoprolol, Propranolol- considered safe first line agents
Beta blockers- intrauterine growth retardation. Especially with Atenolol
Flecainide And Propafenone has been used in maternal and fetal arrhythmias
66
Drug treatment of AVRT with pre excitation in resting ECG
Flecainide or Propafone- in absence of Struct heart disease
IIa indication
Class I is ablation
Class IIb is Amiodarone, Sotolol etc or even beta blockers/CCB
67
Focal atrial tachy 3 features
1. 100-250/mt rate
2. Isoelectric segment in between
3. Microreentry or Automaticity
68
Atrial flutter is otherwise can be called as
Macro reentry Atrial tachy
69
2 types of TYPICAL Atrial flutter
Clockwise- Positive P in infr leads and Negative in V1
Counterclockwise- Opposite pattern
V1 is opposite polarity to infr leads
Normal ECG type is clockwise
70
Atypical Atrial Flutter is different from typical by
Atypical is not Cavotrcuspid isthmus dependent
Usually secondary to Atrial scars due prior surgery etc
71
ECG finding in atypical Atrial flutter
Does not fit Typical flutter findings
| Eg- P wave polarity can be concordant in infr and V1 unlike typical
72
Arrhythmia originating from His Bundle is
SVT. by definition
Not VT
73
Atypical AVNRT forms .....% of AVNRT
20%
74
In typical AVNRT antegrade conduction is via the
Slow pathway
75
Common sites of WPW in order
1. Left lateral-50%
2. Posteroseptal-30%
3. Right anteroseptal and Rt lateral-10% each
76
Short PR interval is
<120 ms
77
Pacemaker mediated tachycardia is due to
Sensing of retrograde p wave as intrinsic p
78
Blanking period is to prevent
Oversensing and cross talk
79
Two parts of refractory period in Pacemaker
Refractory period
First part of refractory period- no sensing- blanking period
Second part of refractory period-relative refractory-senses But no pacing
80
Difference in time interval between Sensed and Paced AV intervals
Paced AV interval is usually 30 seconds more than Sensed AV interval
The interval b/w Sensed or Paced p and V pace
81
Ventricular refractory period is to prevent
T wave oversensing
82
Pacemaker mediated tachycardia can be prevented by
Increasing PVARP-Post Ventricular Atrial Refractory Period
Sensing retrograde P is prevented by Ventricular blanking . During rest of the refractory period it senses but will not initiate the AV delay
83
During BLANKING period there is No—
Sensing
84
How to measure QTc in Afib
1. QT after longest and shortest RR divided by the square root of preceding RR
2. QTc of 10 beats
No final decision
85
Wide QRS adjusted QTc
QTc-(QRS-100)
86
Feature of Second degree SAN block Type 1
PP shortening gradually
So grouping of QRS happens
Pause at end of each group
Look like Sinus arrhythmia
In Type I block pause is less than 2 PP interval
87
Second degree Type II SA block ECG feature
Pause sorrounding dropped P is an exact multiple of preceding PP interval
88
What Sinus pause is significant
A pause of 3 second or more is generally considered to be significant
Pause of 2 seconds may be considered normal
89
Sinus pause definition is
2 seconds or more
> 3 is mostly significant
90
Treatment of Asymptomatic Sinus node disease
No treatment
91
When is Sinus arrhythmia considered abnormal
Only in Digoxin toxicity sinus arrhythmia is considered normal
92
Post Atrial ventricular blanking means
After Atrial pacing Ventricle is deaf /blind for some time. ie it will not sense anything
Done to prevent Atrial pacing being detected by Ventricular lead , which will inhibit ventricular pacing and is catastrophic
So Yes if a Ventricular extra systole happens during this period it will not be detected and there is a chance of ventricular pacing occurring during the vulnerable period
93
Post Atrial ventricular blanking period is usually programmed to ..... ms
30-40 ms
94
How is risk of pacing on a Ventricular extra systole at the vulnerable period ( relative refractory period)after the p wave is prevented
After Post Atrial Ventricular Blanking period there is a period called Safety Window where Ventricular activity is Sensed.
If Ventricular activity is Sensed the AV delay is automatically shortened so that the Ventricular pacing will happen early in the refractory period of the extra systole ( and not in relative refractory period- the vulnerable period)
Also if the activity detected is not a real QRS the Ventricle will be paced - thus giving a safety option
95
The duration of safety window in Ventricular lead is
110 ms or identical as the AV delay if AV delay is less than 110 ms
So after the Post Atrial Ventricular blanking period of 30-40 ms... if the ventricular lead senses an activity the AV delay is shortened so that pacing doesn’t happen on the vulnerable period of QRS at the end of normal AV delay
96
What is Hysteresis in VVI Pacemaker
1. It’s a rate which is set lower than the lower rate of pacing
2. Eg. If lower pacing rate is 60. Then Hysteresis will be set lower than 60. Eg at rate of 50
3. Once the pacemaker senses an intrinsic QRS , it then waits for a longer time than before to check whether some intrinsic activity is going to occur at 50/mt.
4. If the next intrinsic comes within 1200 ms. ( ie at 50/my)It will not pace.
5. Once it starts pacing it paces again at 1000ms interval(60/mt)
97
In 2013 consensus statement how many leads are required to make diagnosis of Brugada
Only one lead
V1 or V2
Uses the BLAST Fragmented QRS criteria in Asymptomatic patients
First degree AV block and LAD in ECG, Late potentials, Atrial fibrillation, ST/T alternans
2005 criteria used family history of Type I Ecg as a criteria
98
The PR interval following an interpolated VPC may be prolonged because
Of the concealed retrograde conduction into the AV node
99
The cardiac vein which travels along with LAD
Great cardiac vein
100
Parasystole occurs because of
Entrance block into the ectopic site. So it cannot be influenced
101
Beta blockers with Most supporting evidence in Afib
Atenolol, Metoprolol, Timolol, Pindalol, Nadolol
Though most appear to have similar efficacy . Labetolol may be little less effective in reducing heart rate at rest
102
Brugada Syndrome there is no real RBBB because it’s a
Repolarisation abnormality and not a depolarization abnormality like RBBB
103
MC use of SAECG
To detect Ventricular Late potentials. (rePresent delayed ventricular activation ) .
Identifies patients at increased risk of re-entrant re-entrant ventricularTachyarrhythmia
Can also be used to find Atrial late potentials- among other uses
104
Role of aspirin in prosthetic valves
75-100 mg in all mechanical prosthesis- Class 1A
IIaB in bio prosthetic valves
105
Isoprenaline reduces QTc so is useful in
Torsades/ Polymorphic VT
106
Short PR interval with normal QRS
Lown Ganong Levine syndrome
107
———million people worldwide have Afib
33 million
108
2017 EMANATE trial
Apixaban safe as routine anticoagulants in Elective cardioversion of AFib
109
Most common sustained cardiac arrhythmia
Afib
110
First Randomised study to show LAA closure during surgery reduces stroke
2017 LAACS study
111
SA Node is situated in
RA/ POSTERIOR WALL/ Near Entrance of SVC
112
AV Node is situated in
RA/ Lower portion of IAS/ Just above the SEPTAL CUSP of TV/ Anterior to Ostium of CORONARY SINUS - ie in the Triangle of Koch
113
Conduction through which bundle is little slower
RIGHT BUNDLE is slower than LEFT
114
Course of His bundle
Pass through fibrous trigone- Along upper portion of membranous IVS( here divides into Rt and Lt)
Rt extends into subendocardial layer of IVS
Lt bundle emerges in LV (passing through upper part of Muscular IVS- ) between RCC& NCC
115
The WIDTH & HEIGHT of .............wave is same in adults and children
P wave
Both less than 2.5 mm in Adults and children
116
The 2 congenital long QTc syndromes
1. Jervell Lange Nielsen syndrome
| 2. Romano Ward syndrome
117
For Bazett equation how to measure RR interval
RR interval just prior to the measured QT interval is taken
118
Lon QTc as a normal variant is seen in
Sleep
| Marked Sinus arrhythmia
119
Rule of thumb for QT INTERVAL
At normal rates if 60-100, QTc should be less than half the RR interval
120
Intendations on T indicate
1. Pwave or
| 2. T/U combination
121
QTc interval indicates
total duration of electrical activity of the Ventricles
122
Percentage of patients having visual symptoms with Ivabradine
15%
123
ST prolongation contributing to QT prolongation is characteristic of
Hypocalcemia
124
Minimum Duration of Afib to diagnose it
Min 30 seconds- ESC 2016
125
Sinus pause definition
2 seconds or more
Uptodate
126
Sinus node exit block identification
First degree- cannot be differentiated from Normal
Third degree- cannot be differentiated from SINUS ARREST
Second degree- TYPE2- Pause PP interval is a multiple of basic PP interval
TYPE1- pp progressively REDUCES.Then pause. Pause is less than 2 Times PP interval
