Transcript Baby Steps to ECG

Baby Steps to ECG
Dr Saqib Mahmud
MRCP(UK), MRCPS(Glasg), MRCGP
Electrical Conducting system
ECG LEADS
leads representing regions
Anatomic region of heart & associated
coronary artery
• Inferior MI----------------RCA
• Antero-septal MI---------LAD
• Antero-lateral MI---------Circumflex
• Posterior MI--------------RCA
----------------------------------------------------------• Inferior leads-------------II, III, aVF
• Antero-septal leads------V1,V2,V3&V4
• Antero-lateral leads------I,aVL,V2-V6
Normal
ECG
PR interval0.12s0.2s(not>1 large sq)
QRS duration0.12s
(not>3 small squares)
PQRST
ST segmentisoelectric
T upright
ECG reporting-systematic
approach
1.
2.
3.
4.
5.
6.
7.
Rate
Rhythm & P waves
Conduction intervals
Axis
QRS complexes-narrow, wide, bizarre
ST segments-elevation or depression
T waves-inverted, upright, peaked
How to calculate heart rate
Relationship b/w R-R interval (large
squares)& heart rate
-----------------------------------------------------------------R-R interval (large squares)
• 1
• 2
• 3
• 4
• 5
• 6
heart rate
300
150
100
75
60
50
QRS nomenclature
Axis
Cardiac axis
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•
•
•
•
Normal axis-’’ double thumbs up’’(I&III+)
RAD--- I –ve, III +ve
LAD--- I +ve, III –ve
--------------------------------------------RAD-(causes): normal in children, R vent
hypertrophy, PE, ASD/ VSD, anterolateral MI
• LAD-inferior MI, WpW, emphysema,
conduction defects
Bundle branch block
•
1.
2.
3.
•
1.
2.
RBBB
Tall R wave V1
QRS>0.12sec
RsR-V1
LBBB
QS-V1,V2
QRS>0.12
LBBB
RBBB+LAD
Atrial flutter & fibrillation
•
1.
2.
•
1.
2.
3.
Atrial flutter
Saw tooth appearance
Rapid & regular rhythm
Atrial fibrillation
No P waves or bizarre P waves
Always irregular rhythm
Can be slow or rate controlled
ACS classification
•
Heart block
1st degree HB-prolonged PR>0.2sec
Causes-increased vagal tone, IHD, Rh fever, dig
toxicity, electrolyte imbalance,myocarditis
• 2nd degree HB1. Mobitz type 1 or wenckebeck-progressively
increased PR,non conducted beat,short PR
(causes-inf MI, athelete, drugs-Ca & beta
blockers,digoxin)
2. Mobitz type 2-(2:1) fixed PR, one P wave
not folowed by QRS-(causes-degenerative
disease of conducting system, anteroseptal
MI-may herald CHB)
CHB or 3rd degree HB
• Atrial contraction normal-no beats
conducted to ventricles
• Ventricles excited by slow escape
rhythm
• ECG-no relationship b/w P waves and Q
waves
• Bizarre or wide QRS complexes
• Causes-degenerative fibrosis of bundle
of his, MI, drugs eg betablockers,
digoxin
wpw
hyperkalaemia
P-pulmonale
SI,QIII,TIII-RV strain
Thank you
Presentation
on
Peripheral vascular disease
Next time if you are
interested