Regularity/Rhythm Do the QRS complexes come at a regular interval?

Regular rhythm with a P wave before each complex: SINUS RHYHTM Irregularly irregular rhythm: ATRIAL FIBRILLATION Regular rhythm but with no p waves: ATRIAL FLUTTER Regular but long PR interval: FIRST DEGREE HEART BLOCK Regularly irregular: SECOND DEGREE HEART BLOCK Regular with no clear complexes: VENTRICULAR TACHYCARDIA Irregular and disorganised: VENTRICULAR FIBRILLATION

PR INTERVAL GREATER THAN 220ms!

QRS (less than 120ms-number of small squares x 40) Morphology Do all complexes look the same? Are all complexes the same duration? QRS (less than 120ms-number of small squares x 40) P wave (Less than 120ms)

Broad QRS morphology: BUNDLE BRANCH BLOCK NORMAL ECG RIGHT BUNDLE BRANCH BLOCK ‘RSR’ pattern LEFT BUNDLE BRANCH BLOCK Deep S waves

BBB happens with every complex, ectopic's come and go ** 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 ** 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) Can have ventricular ectopic's which are known as VEs or PVCs Can also have atrial ectopic's which are known as SVEs or PACs : these will look the same as a normal beat!! These beats can either occur on their own (isolated ectopic) or in pairs (Couplets) or in threes (triplets), etc..

ST Segments ST elevation- STEMI ST Depression- Angina Indication of heart attacks (Myocardial infraction) ST elevation- STEMI ST Depression- Angina