Download The basic`s of a 12 lead ECG part 3

Regularity/Rhythm
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Do the QRS complexes come at a regular interval?
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Regular rhythm with a P wave before each complex: SINUS RHYHTM
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Irregularly irregular rhythm: ATRIAL FIBRILLATION
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Regular rhythm but with no p waves: ATRIAL FLUTTER
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Regular but long PR interval: FIRST DEGREE HEART BLOCK
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Regularly irregular: SECOND DEGREE HEART BLOCK
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Regular with no clear complexes: VENTRICULAR TACHYCARDIA
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Irregular and disorganised: VENTRICULAR FIBRILLATION
PR INTERVAL GREATER THAN 220ms!
Morphology
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Do all complexes look the same?
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Are all complexes the same duration?
QRS (less than 120ms-number of small squares x 40)
P wave (Less than 120ms)
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Broad QRS morphology: BUNDLE BRANCH BLOCK
NORMAL ECG
RIGHT BUNDLE BRANCH BLOCK
‘RSR’ pattern
LEFT BUNDLE BRANCH BLOCK
Deep S waves
Ectopic's
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Different morphology to the normal sinus beat however it is not a bundle branch
block even though it may look like it!
•
BBB happens with every complex, ectopic's come and go **
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These are just extra heart beats that originate from somewhere else in the heart
(the ventricles or somewhere other than the SAN in the atria)
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Can have ventricular ectopic's which are known as VEs or PVCs
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Can also have atrial ectopic's which are known as SVEs or PACs : these will look the
same as a normal beat!!
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These beats can either occur on their own (isolated ectopic) or in pairs (Couplets)
or in threes (triplets), etc..
ST Segments
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Indication of heart attacks (Myocardial infraction)
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ST elevation- STEMI
ST Depression- Angina