Arrhythmias Flashcards
Time course of VPCs from birth to adults
Commonly occur in infancy.; declines in incidence in early childhood
Becomes common again in adolescence and adulthood
Ventriculophasic Sinus arrhythmias
The 2 p waves sorrounding a QRS occurs at a faster rate
Exact reason not known
?increased SA nodal artery flow
How to identify a WPW with long refractory period
Intermittent loss of delta ; at rest or exercise or with procainamide
Chances of Afib with fast conduction less
First step in Arruda algorithm For WPW
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
Most common type of WPW
LEFT LATERAL
Second step in Arruda for WPW
Coronary Sinus step
Negative DELTA in Ld II ( mimics IWMI)
SVT originates from
HIS bundle and above
Cardiac compromise happens when heart rate is more than
200/mt i.e. < 300 ms
60000ms/300ms=200
Atypical AVNRT is precipitated by —-ectopics
Ventricular
Long RP tachy means
RP> PR
Irregular SVT
AF,MAT,AFlutter with varying condxn
Atrial tachy is Short or Long RP
Usually Long RP. Or if Short RP , the short RP >90 ms
Epicardium mapping in VT is indicated in structural diseases like
CHAGAS
ARVD
Frequent VPCs definition
- More than 60/ hour or 1/minute -ESC cardiology
2. >1% or > 1000 per day- Korean heart journal
ECG findings which suggest Brugada syndrome in an asymptomatic type 1 pattern
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
Use of family history in diagnosis of BRUGADA SYNDROME
- Family history of SCD <45 yrs
2. Type 1 ECG pattern in family - This was there in 2005 criteria but removed in 2013 criteria
In pts with WPW and AF higher risk is suggested by persistence of accessory pathway conduction with RR intervals
Less than 250ms
SCD in apparently normal hearts incidence
5-20%
In Lowns grading of VPB Ron T is
Grade 5 . Most severe
Lowns grading of Multifocsl VPBs
Grade3
Lowns grading of couplets and NSVT
Grade 4
Location of carotid Sinus is b/w
Angle of mandible and Superior border of Thyroid cartilage
What direction of current do V1/2 measure
Anterior/Posterior forces
Right/Left forces are measured by which leads
V6, Lead I
If all frontal plane leads are isoelectric the axis is
Cannot be determined i.e. Indeterminate.. This is a normal variant
Antidote of adenosine
Aminophylline
Location of carotid Sinus
Inferior to angle of mandible at level of Thyroid cartilage
ACC/AHA/HRS definition of Non valvular Afib 2014 Jan
In the absence of
- Rheumatic MITRAL VALVE DISEASE
- Mitral valve repair
- Prosthetic valve
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
MVP mode of pacing
Managed Ventricular Pacing
Uses AV Search hysteresis
Primary mode of Pacing in MVP Mode is
AAIR
Heart rate is said to be regular if the RR variability is
Less than 60 ms
Internet
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
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
An axis change of ______indicates VT
40 degree
An axis of ____ with RBBB indicates VT
-30 or more
An axis of _____indicates VT in LBBB
90 or more
A QRS duration of> ______ indicates VT in RBBB
140
In LBBB it is 160
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
3 features of AV dissociation in VT
- Dissociated p waves
- Fusion beats
- Capture beats
Morphological criteria in V6 for VT with RBBB
rS in V6 . s/o VT
If R/s is more than 1 it’s SVT
Morphological criteria for VT with LBBB in V6
qR pattern in V6
Anterior fascicle supplies which part of LV
ALU–Anterior supplies LATERAL and UPPER parts
Short QT syndrome QT interval
360 or less
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
MC type of LQTS
Type 1
Deafness is a feature
Triggers for LQTS
LQTS1- Exercise
LQTS2- Loud noise
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
Paroxysmal Afib means
Reverts in 7 days
Main risk of sub clinical Hyperthyroidism
Afib