ECG Interpretation PDF

ECG Interpretation University of St. Andrews School of Medicine The ECG MADE EASY J R Hampton 9th Edition Dr Predrag Bjelogrlić Join at vevox.app Or search Vevox in the app store ID: XXX-XXX-XXX ECG – A Methodical Approach 1. Identity, Standardisation 2. Rate 3. Rhythm 4. P Wave 5. P–R Interv...

ECG Interpretation University of St. Andrews School of Medicine The ECG MADE EASY J R Hampton 9th Edition Dr Predrag Bjelogrlić Join at vevox.app Or search Vevox in the app store ID: XXX-XXX-XXX ECG – A Methodical Approach 1. Identity, Standardisation 2. Rate 3. Rhythm 4. P Wave 5. P–R Interval 6. QRS Complex 7. QT Interval 8. ST Segment 9. T Wave 10. Axis 11. Other Abnormal Components 12. Formulate an Interpretation Identity, Standardisation  First confirm patient’s name and age and ECG’s date.  Standardisation.  Make sure that 1cm = 1mV and  Paper speed 25mm/sec Join: vevox.app ID: XXX-XXX-XXX How old is patient on your ECG? POLL OPEN 1. 12 years 2. 19 years 3. 21 years 4. 22 years Vote Trigger Rate Rate  Calculation:  300 divide by the number of big squares per R – R interval.  Calculate this in the second lead  Normal rate 60-100 b.p.m  Bradycardia <60  Tachycardia >100 R-R Duration (s) Big Squares Rate per min 0.2 1 300 0.4 2 150 0.6 3 100 0.8 4 75 1.0 5 60 1.2 6 50 1.4 7 43 Rate (300/5=60) Join: vevox.app ID: XXX-XXX-XXX POLL OPEN The rate on this ECG is...(bpm) 1. 50 2. 54 3. 60 4. 70 5. Do not know Vote Trigger Rhythm  Are the normal P waves present (<0.25mV, and upright in II III and AVF)?  Are the QRS complex narrow-normal <120 ms (0.12s) or wide >120 ms (0.12s)?  Relationship between P waves and QRS complexes. (One P wave followed by one QRS complex)  Is the rhythm regular or irregular (arrhythmia)? Sinus Rhythm     Normal P waves Normal QRS complexes One P wave followed by one QRS complex Regular rhythm Sinus Rhythm  Regular rhythm  Mark position of 3 successive R waves  Slide the mark forward and check that intervals are equal Sinus Rhythm  Regular rhythm  Mark position of 3 successive R waves  Slide the mark forward and check that intervals are equal Sinus Rhythm  Regular rhythm  Mark position of 3 successive R waves  Slide the mark forward and check that intervals are equal Join: vevox.app ID: XXX-XXX-XXX POLL OPEN Rhythm on this ECG is... 1. Regular 2. Irregular 3. Do not know Vote Trigger Rhythm - Arrhythmia  No discernible P waves and irregular QRS complexes Rhythm - Arrhythmia Nodal Rhythm – Arrhythmia  Normal QRS complexes but absent P waves Ventricular Rhythm P Wave (Atrial Depolarisation)  <0.25mV, and upright in II III and AVF  Normally precedes each QRS complex  Absent P wave:  Atrial fibrillation  Nodal (junctional) rhythm Join: vevox.app ID: XXX-XXX-XXX This ECG P wave is normal Do you agree? POLL OPEN 1. Yes 2. No 3. Do not know Vote Trigger Abnormal P Waves  P-Mitrale:  Bifid P wave = left atrial hypertrophy Abnormal P Waves  P-Pulmonale:  Peaked P wave = right atrial hypertrophy P-R Interval (Time Between Atrial and Ventricular Depolarisation)  Measure from the beginning of P to the beginning of Q wave  Normal range 120-200 ms (0.12-0.2 s)  Check P-R Interval on your ECG Join: vevox.app ID: XXX-XXX-XXX Duration of P-R Interval on this ECG is... POLL OPEN 1. 80 ms (0.08 s) 2. 160 ms (0.16 s) 3. 120 ms (0.12 s) 4. 200 ms (0.20 s) 5. Do not know Vote Trigger P-R Interval  Prolonged >200 ms (0.2 s) implies delayed AV conduction QRS Complex (Ventricular Depolarisation)  Measure from the beginning of Q to the end of S wave  Normal Duration <120 ms (0.12 s)  Normal Q wave <40 ms (0.04 s) and <2mm depth Join: vevox.app ID: XXX-XXX-XXX POLL OPEN Duration of QRS complex on this ECG is... 1. 80ms (0.08 s) 2. 100ms (0.10 s) 3. 120 ms (0.12 s) 4. 160 ms (0.16 s) 5. Do not know Vote Trigger Join: vevox.app ID: XXX-XXX-XXX Is there evidence of abnormal Q waves in this ECG? POLL OPEN 1. Yes 2. No Vote Trigger Abnormal QRS Complex  If >120ms (0.12 s)  Ventricular Conduction Defects  Bundle Branch Block  Left and Right Bundle Branch Block  Low voltage <5mm:     Hypothyroidism COAD Myocarditis Pericarditis and Pericardial effusion Abnormal QRS Complex  Left Ventricular Hypertrophy:  R wave in V5 >25mm or  Sum of the S wave in V1 and R wave in V5 or V6 >35mm  Sokolow-Lyon index Abnormal QRS Complex  Right Ventricular Hypertrophy:  Dominant R wave in V1  T wave inversion in V1 – V3 or V4  Deep S wave in V6 Significant Q Wave  >40ms (0.04 s)  Depth >2 mm.  Present couple of hours/days after acute MI  If present in lead III consider PE. Join: vevox.app ID: XXX-XXX-XXX This ECG shows sign of ventricular hypertrophy. POLL OPEN 1. Yes 2. No 3. Do not know Vote Trigger QT Interval  Measure from start QRS to end of T wave – varies with rate.  Corrected QTc Interval  QTc=QT/√RR Normal 380-420 ms (0.38-0.42 sec)  Measure QTc on your ECG Join: vevox.app ID: XXX-XXX-XXX Duration of QT interval on this ECG is... POLL OPEN 1. 420 ms (0.42 s) 2. 380 ms (0.38 s) 3. 365 ms (0.37 s) 4. Do not know Vote Trigger Prolonged QT Interval         Acute Myocardial Ischaemia Myocarditis Bradycardia Head Injury Hypothermia U&E Imbalance (K+ Ca2+ Mg2+ ) Congenital Drugs (Quinidine, Antihistamines, Macrolides, Amiodarone, Phenothiazines) ST Segment  Time from the end of ventricular depolarisation to the start of ventricular repolarisation  Usually Isoelectric  Check ST segment on your ECG Join: vevox.app ID: XXX-XXX-XXX The ST segment is isoelectric on this ECG. POLL OPEN 1. True 2. False 3. Do not know Vote Trigger Abnormal ST segment  Elevation > 2mm  In two adjacent chest leads or  Elevation > 1mm  In two adjacent limb leads  = INFARCTION  Depression = Ischaemia T Wave (Ventricular Repolarisation)  Normally inverted in VR and V1 and in V2 in young  Abnormal if inverted in I, II and V4 -V6 (Ischaemia /Infarction) Join: vevox.app ID: XXX-XXX-XXX POLL OPEN T wave on this ECG is... 1. Inverted in lead I 2. Inverted in V3 3. Inverted in aVR 4. Do not know Vote Trigger T Wave Digoxin effects  T Wave inversion  ST segment sloping depression Axis (normal between -30° and +90°)  Sum of all ventricular forces during ventricular depolarisation.  Predominantly upwards deflections in leads I II and III. Left Axis Deviation (-30°to -90°)  Negative QRS deflections in II and III  LV Hypertrophy, MI Right Axis Deviation (+90° to +180°)  Negative QRS deflections in I  RV Hypertrophy, PE, MI Join: vevox.app ID: XXX-XXX-XXX POLL OPEN The axis in this ECG shows… 1. Right deviation 2. Normal axis 3. Left deviation 4. Do not know Vote Trigger Other Abnormalities  Myocardial Infarction  Pulmonary Embolism  Metabolic Abnormalities MI ECG Changes  During an Acute MI, the ECG evolves through 3 stages:  T wave peaking followed by T wave inversion  ST segment elevation  Appearance of new Q waves STEMI Evolution Previous ECG At onset of MI Within minutes Hours to days No change ST elevation Q wave R shortened T inversion ST elevation T inversion Q waves Weeks ST resolved Weeks onward s T reverts Q persists MI ECG Localizing the Infarct  Anterior Infarction:  Any of precordial leads (V1 through V6)  Lateral Infarction:  Leads I, AVL, V5 and V6  Inferior Infarction:  Leads II, III, and AVF  Posterior Infarction:  Reciprocal changes in lead V1 (STsegment depression, tall R wave) Anterior Infarction  Sinus rhythm  Q waves in leads V2 - V4  Inverted T waves in leads V4 - V6 Anterolateral Infarction  Sinus rhythm  Q waves in leads I, II, AVL, V3 – V 5  Raised ST segments in leads V2 – V6 Inferior Infarction  Sinus rhythm  Q Waves in leads III and AVF  Depressed (ischaemic) ST segments in leads AVL and V6 Location of MI Pulmonary Embolism  Large S wave in lead I  Deep Q wave in lead III  Inverted T wave in lead III Metabolic Abnormalities  Hyperkalaemia:  Tall, tented T wave, widened QRS.  Hypokalaemia:  Small T waves, prominent U waves.  Hypercalcaemia:  Short QT interval.  Hypocalcaemia:  Long QT interval, small T waves. Join: vevox.app ID: XXX-XXX-XXX POLL OPEN Interpretation of this ECG... 1. Irregular sinus rhythm 2. Sinus arrhythmia 3. Pulmonary embolism 4. Sinus bradycardia 5. Normal ECG 6. Ventricular hypertrophy 7. I do not know – too difficult for me Vote Trigger Join: vevox.app ID: XXX-XXX-XXX POLL OPEN This lecture was useful 1. Strongly Agree 2. Agree 3. Neutral 4. Disagree 5. Strongly Disagree Vote Trigger THANK YOU!