Basic electrocardiography reading. R3 lee wei-chieh

Transcription

1 Basic electrocardiography reading R3 lee wei-chieh

2 The Normal Conduction System

3 Lead Placement avf

4 Limb Leads

5 Precordial Leads

6 Interpretation Rate Rhythm Interval Axis Chamber abnormality QRST change

7 What is the heart rate? (300 / 6) = 50 bpm

8 Rule of 300

9 Rhythm Sinus Originating from SA node P wave before every QRS P wave in same direction as QRS

10 PR 0.20 sec (less than one large box) QRS sec (1 2 small boxes) QT 450 ms in men, 460 ms in women Based on sex / heart rate Half the R R interval with normal HR Corrected QT (QTc) QTm/ (R R) Normal Intervals

11 The QRS Axis Represents the overall direction of the heart s activity Axis of 30 to +90 degrees is normal

12 The Quadrant Approach QRS up in I and up in avf = Normal

13 Cardiac Enlargement and Hypertrophy Right atrial overload: increase in P wave amplitude (2.5 mm) Left atrial overload: biphasic P wave in V 1 with a broad negative component or a broad (120 ms), often notched P wave in one or more limb leads

14 Cardiac Enlargement and Hypertrophy Right ventricular hypertrophy tall R wave in lead V 1 (R S wave) qr pattern in V 1 or V 3 R Prominent S waves may occur in the left lateral precordial leads

15 Cardiac Enlargement and Hypertrophy Left ventricular hypertrophy Sokolow Lyon index: S in V 1 + R in V 5 or V 6 (whichever is larger) 35 mm ( 7 large squares) R in avl 11 mm Cornell voltage criteria: S in V 3 + R in avl > 28 mm (men) S in V 3 + R in avl > 20 mm (women) Romhilt Estes point score system: "diagnostic" >5 points; "probable" 4 points

16 ECG Criteria Romhilt Estes point score system Voltage Criteria (any of): R or S in limb leads 20 mm S in V 1 or V 2 30 mm R in V 5 or V 6 30 mm ST T Abnormalities: ST T vector opposite to QRS without digitalis ST T vector opposite to QRS with digitalis Negative terminal P mode in V 1 1mm in depth and 0.04 sec in duration (indicates left atrial enlargement) Left axis deviation (QRS of 30 or more) 3 QRS duration 0.09 sec 2 Delayed intrinsicoid deflection in V 5 or V 6 (>0.05 sec) 1 Other voltage based criteria for LVH include: Lead I: R wave > 14 mm, Lead avr: S wave > 15 mm, Lead avl: R wave > 12 mm, Lead avf: R wave > 21 mm, Lead V 5 : R wave > 26 mm, Lead V 6 : R wave > 20 mm Points

17 QRST change Baseline Tall or inverted T wave (infarct), ST segment may be depressed (angina) Elevated ST segment, T wave may invert Abnormal Q wave, ST segment may be elevated and T wave may be inverted Abnormal Q wave, ST segment and T wave returned to normal

18 blood supply of coronary artery Location lead reciprocal change supply Lat. Wall I, avl, V5, V6 V1 V3 LCX Inf. wall II, III, avf I, avl RCA marginal branch Septum V1, V2 no Septal br. of LAD Ant. wall V3, V4 II, III, avf Diagnal br. of LAD Post. wall no V1 V4 LCX( 多 ) or RCA( 少 ) RV V1R V6R (*V4R) RCA marginal branch

19 QRST change

20 Differential Diagnosis of Tachycardia Tachycardi a Regular Irregular Narrow Complex ST SVT Atrial flutter A fib A flutter w/ variable conduction MAT Wide Complex ST w/ aberrancy SVT w/ aberrancy VT A fib w/ aberrancy A fib w/ WPW VT

21 P waves absent Baseline fibrillation waves Irregular ventricular rhythm Atrial rate beats/min Ventricular rate beats/min Atrial fibrillation

22 Saw-toothed baseline F (flutter) waves Regular ventricular rhythm Atrial rate beats/min Ventricular rate typically 150 bpm (with 2:1 AV block > 4:1 > 3:1 or 1:1) Atrial flutter

23 Abnormal P wave morphology Atrial rate bpm Ventricular rhythm usually regular and variable ventricular rate Atrial tachycardia

24 AVNRT

25 AVRT orthodromic antidromic

26 Wolff Parkinson White syndrome Type A,B: delta wave/qrs complex over precordial leads 的形狀而區分 Type A: accessory pathway 由 LA 後壁進入 LV 後壁, 是在所有 precordial leads 的 delta wave 都是 upright positive, 在 lead V1 的 R 會比 S 大 Type B: accessory pathway 由 RA 後或側面進入 RV, V2 V6 的 delta wave/qrs complex 都是 upright positive, V1 和 V2 lead 會有 negative 的 delta wave 和 QRS complex

27 AV block First degree block PR interval fixed and > 0.2 sec Second degree block, Mobitz type 1 (Wenckebach) PR gradually lengthened, then drop QRS Second degree block, Mobitz type 2 PR fixed, but drop QRS randomly Type 3 block PR and QRS dissociated

28 Bundle branch block

29 Bundle branch block

30 Bundle branch block

31 Bundle branch block

32 Practice

33 45 year old man, asymptomatic

34 76 year old man, dyspnea

35 79 year old man, 45 minutes after thrombolytic therapy, relieved

36 48 year old man, severe lightheadedness with walking, receive new anti hypertension medication

37 62 year old man, complained of progressive dyspnea after missing regular hemodialysis twice

38 54 year old man, 24 hours after receive thrombolytic therapy

39 39 year old, man

40 Brugada syndrome Circulation, 2005; 111(5):

41 41 year old woman, nausea and vomiting

42 48 year old man, report eights hour of chest pain and arm pain

43 38 year old man, chest pain, nausea, diaphrosis

44 Discussion

45 Discussion

46 75 year old woman, took too many medication

47 82 year old man, increase B blocker dose, felt lightheadedness

48 43 year old man, asymptomatic

49 86 year old man, complained of generalized weakness

50 40 year old woman, palpitation and lightheadedness

51 57 year old man, chest pressure and diaphrosis

52 74 year old man, chest pain and palpitation

53 85 year old man, syncope

54 33 year old man, sudden chest pain and dyspnea

55 44 year old woman, palpitation

56 46 year old man, four days of nausea and vomiting

57 Thank you for listening!

58 Basic Competency in Electrocardiography ST T, AND U ABNORMALITIES Early repolarization (normal variant) Nonspecific ST T abnormalities ST elevation (transmural injury) ST elevation (pericarditis pattern) Symmetrical T wave inversion Hyperacute T waves Prominent upright U waves U wave inversion Prolonged QT interval MI PATTERNS (acute, recent, old) Inferior, Inferoposterior, Inferoposterolateral MI True posterior MI Anteroseptal, Anterior, Anterolateral MI High lateral MI Non Q wave MI Right ventricular MI CLINICAL DISORDERS Chronic pulmonary disease pattern Suggests hypokalemia, hyperkalemia Suggests hypocalcemia, hypercalcemia Suggests digoxin effect, digoxin toxicity Suggests CNS disease PACEMAKER ECG Atrial paced rhythm Ventricular paced rhythm AV sequential paced rhythm Failure to capture (atrial or ventricular) Failure to inhibit (atrial or ventricular) Failure to pace (atrial or ventricular)