1. The document discusses electrocardiographic (ECG) interpretation including determining cardiac rate and rhythm, identifying conduction disturbances, myocardial ischemia or infarction, and other abnormalities. 2. It provides details on properly placing ECG leads and determining the cardiac axis. Common rhythms, conduction blocks, hypertrophy, and other ECG findings are explained. 3. A mnemonic device, RRAHIM, is presented to guide the systematic interpretation of an ECG, covering rate, rhythm, axis, hypertrophy, ischemia/infarction, and other findings.

1. Electrocardiographic Cases Crisbert I. Cualteros, M.D.

2. Sinus Rhythm

3. SR frequent PVDs PRWP lat wall ischemia

4. ECG Indications determine cardiac rate define cardiac rhythm diagnose old or new MI identify intracardiac conduction disturbances aid in the diagnosis of IHD, pericarditis, myocarditis, electrolyte abnormalities and pacemaker malfunction

5. V1 = 4th ICS, R sternal border V2 = 4th ICS, L sternal border V3 = halfway between V2 and V4 V4 = 5th ICS, L MCL V5 = 5th ICS, anterior axillary line V6 = 5th ICS, L mid-midaxillary line V3R = halfway between V1 and V4R V4R = 5th ICS, R MCL Lead Locations

6. Correspondence Anteroseptal wall V1-V3 Lateral wall V5, V6 Anterior wall V3, V4 Septal wall V1, V2 High lateral wall I, aVL Inferior wall II, III, aVF Area Leads

7. Area Leads RV wall V3R and V4R Posterior LV wall Mirror image of V 1/2 Diffuse/global/massive Almost all leads Inferolateral wall V5, V6, II, III, aVF Anterolateral wall V3-V6, I, aVL

9. RRAHIM Components of ECG interpretation R ate R hythm A xis H ypertrophy I schemia and Infarction M iscellaneous (normal variants)

16. Rate Mnemonic: 300, 150, 100, 75, 60, 50 Formula: 1500 / # of small boxes 300 / # of big boxes Bradycardia = <60 bpm Normal Rate = 60-100 bpm Tachycardia = >100 bpm

17. What is the rate? 1500/28 or 300/5.6 53 bpm

18. What is the rate? 1500/12 or 300/2.4 125 bpm

19. Rhythm Identify the P wave Check relation of P wave to QRS Normal: P wave is before QRS SVT, heart blocks: P wave after QRS or burried Check PR interval ( 0.12 - 0.20s ) Shortened: WPW Prolonged: 1 st and 2 nd degree AV block

20. Check QRS duration (< 0.10 s ) Widened: bundle branch blocks Check relation of R-R and P-P int PP < RR: complete heart block PP > RR: AV dissociation

21. Common Rhythm Interpretations Sinus rhythm Supraventricular arrhythmias Atrial fibrillation Atrial flutter Supraventricular tachycardia (SVT) Heart Blocks First-degree AV block Second-degree AV block Mobitz Type I (Wenckebach) Mobitz Type II

22. Third-degree AV block Left or Right Bundle Branch Block Complete Incomplete Ventricular Arrhythmias Premature Ventricular Depolarization (PVD) Ventricular Tachycardia (V-tach) Sustained Non-sustained Ventricular fibrillation (V-fib)

23. Axis Determination get the average QRS vector from the isoelectric baseline in Leads I and AVF if the average QRS vector is above baseline -> (+) QRS deflection if the average QRS vector is below baseline -> (-) QRS deflection

24. Axis -- -- indeterminate + -- RAD -- + LAD + + Normal Axis AVF Lead 1

26. Normal (-30 to +90) RAD Indeterminate LAD

27. Axis - 90 AVF indeterminate LAD ± 180 0 I RAD normal (-30 to +90) + 90

28. What is the axis?

29. Axis Differentials WPW syndrome WPW syndrome LPFB LAFB Pulmonary embolism LBBB Lateral wall MI Inferior wall MI RVH (COPD, cor pul) LVH (HTN) N variant: thin, tall N variant: short, fat RAD LAD

30. Hypertrophy Six Possibilities No hypertrophy LVH RVH LAE RAE combination

31. LVH criteria 3 Methods 1) S wave in V1 + R wave in V5/6 > 35mm 2) R in AVL > 11mm 3) Romhilt and Estes Criteria (best)

32. SR, LVH with Strain Pattern, Old Anteroseptal Wall MI

33. RVH Criteria RAD of ≥ +110, with any of the ff: V1: R wave > S wave COPD RBBB True posterior infarction WPW Deep S wave in V5-6 COPD ST depression and T wave inversion in V1-3

34. LAE (p mitrale) 2 Methods V1: wide terminal component of P wave ≥ 1 mm wide (0.04 s) and ≥ 1 mm deep Any lead: P wave wider than 0.12s or with a ≥ 1 mm notch in the middle

35. ST, RAD, LAE, RVH

36. RAE (p pulmonale) 2 Methods V1: tall initial component of P wave ≥ 2mm wide and ≥ 2 mm tall Any Lead: P wave ≥ 2.5 mm tall

37. RRAHIM Components of ECG interpretation Rate Rhythm Axis Hypertrophy Ischemia and Infarction Miscellaneous (normal variants)

38. Myocardial Ischemia 1 mm ST-segment depression Symmetrically/inverted T waves Abnormally tall T waves Normalization of abnormal T waves Prolongation of QT interval Arrhythmias, BBB, AV blocks or electrical alternans

39. SR, Anterolateral Wall Ischemia

40. Myocardial infarction Criteria (any) ST elevation ≥ 2 Chest leads: ≥ 2 mm elevation or ≥ 2 Limb leads: ≥ 1 mm elevation Q waves ≥ 0.04s (1 small square)

41. Timing of MI/ECG 0-6 hours 6-24 h 24 -72 h 72 h – 6 weeks > 6 wk

42. Differentials for ST elevation Acute pericarditis Ventricular aneurysm Severe LV wall hypokinesia Early repolarization changes Variant (prinzmetal) angina

43. Q waves never significant in aVR not significant in V1 unless with abnormalities in other precordial leads not significant in III unless with abnormalities in II, aVF more reliable if associated with ST changes Not significant in V1-V3 if (+) LBBB , but significant if (+) RBBB

44. Criteria for Pathologic Q waves ≥ 0.04 sec in duration ≥ 25% of the R wave amplitude

45. Recent Anteroseptal Wall MI

46. SR, Acute Inferior Wall MI

47. RRAHIM Components of ECG interpretation R ate R hythm A xis H ypertrophy I schemia and Infarction M iscellaneous (normal variants)

48. Hypokalemia V2, V3: u wave as tall or taller than T wave Hyperkalemia Chest leads: height of T wave > 10 mm Limb leads: height of T wave > 5 mm Hypocalcemia Prolonged QT interval, longer than ½ the RR interval Hypercalcemia Shortened QT interval

50. Poor R wave Progression (PRWP) Height of Rwave in V3 < 3 mm Differentials Old anteroseptal wall MI LVH Normal variant: heart rotated clockwise LBBB Early Repolarization Changes (ERP) V2-V4: ST segment elevation of 2-3 mm Normal variant, usually in males < 40y Differentials Acute anteroseptal wall MI Acute pericarditis

51. SR, ERP

52. SR, ERP

53. SR, PRWP

54. Hyperkalemia tall, peaked T waves usually >10 mm in the chest leads

55. Hypokalemia abnormally tall U waves most prominent in V2 and V3

56. Low-voltage QRS QRS in all limb leads is < 5 mm Artifacts Irregular spikes or undulations on the ECG baseline not found in other segments Causes Patient movement (shivering) Poor electrode contact

57. Atrial Fibrillation Criteria No P waves Irregular fibrillatory waves Irregularly irregular ventricular rhythm Acute if < 48h

58. Top 5 causes of AF (EVICT) E thanol (Holiday Heart Syndrome) V alvular heart disease (MS) I HD C ardiomyopathy T hyrotoxicosis

60. AF with RVR PRWP NSSTTWC

62. AF with MVR, RBBB

63. AF with RVR, lateral wall ischemia

64. AV Nodal Blocks First Degree AV Block P-R interval > 0.21 sec One-to-one AV conduction

65. Sinus Bradycardia with first degree AV block

66. AV Nodal Blocks Second Degree AV Block Sinus rhythm Some P waves not followed by QRS complx Mobitz I (Wenckebach) Increasing PR interval -> dropped beat

67. Mobitz II PR interval prolonged but constant Third Degree AV Block or Complete Heart Block AV dissociation P waves seen marching through the QRS PP interval < RR interval Idioventricular rhythm

68. SR with 2 nd degree AV block (Wenckebach)

69. 3 rd degree AV block

70. Intraventricular Blocks Complete RBBB QRS duration ≥ 0.12 seconds QRS in V1 has an rsR’ configuration or is a solitary R wave

71. Intraventricular Blocks Complete LBBB QRS duration ≥ 0.12 seconds QRS is notched and splintered QRS has a QS or rS deflection in V1

72. .

73. SR with cRBBB

74. ST with cRBBB

75. V-Tach Criteria ≥ 3 consecutive QRS complexes… of uniform configuration of ventricular origin > 100 bpm

76. Monomorphic Sustained VT: > 30 s Hemodynamic compromise Requires intervention for termination Non-sustained V-Tach Morphology

77. Polymorphic beat to beat variation in QRS complexes V-Tach Morphology

78. SupraV Tach Criteria regular succession of QRS complexes with normal duration and configuration rate 150 – 250 bpm P waves not identifiable (superimposed on QRS) or preceed / succeed the QRS complex

81. Sinus Rhythm

82. Second-degree AV block, type II

83. Third Degree AV Block

84. Acute Inferior Wall MI

85. AF with RVR

86. AF with SVR

87. Anteroseptal Wall MI

88. Atrial Flutter with 2:1 conduction

89. Digoxin Effect

90. ERP

91. First-Degree AV block, SB

92. Frequent PVCs in Bigeminy

93. Hyperkalemia

94. Left Bundle Branch Block

95. Right Bundle Branch Block

96. SVT

97. Ventricular Fibrillation

98. Ventricular Tachycardia

99. Ventricular Tachycardia

100. WPW Syndrome

102. SR LAE LVH with strain Pattern ERP vs Acute injury pattern in the anteroseptal wall

103. SR, LAH, LAE, IVCD, LVH, lateral wall ischemia and/or strain. NSSTTWC, inferior wall. ERP vs. acute injury, anteroseptal wall. 66 male (+) HTN (+) DM 5 pack years cc: fever, cough body malaise 150/80, 88, 20 trop I negative SR, LAE, with an acute injury pattern in the anteroseptal wall

104. D.R., 41 male (-) medical problem (-) smoker (-) alcoholic cc: 2 months productive cough low-grade fever 120/80, 104, 36 imp: PTB III meds: combivent ranitidine levofloxacin

105. Atrial flutter/atrial fibrillation with NSSTTWC

106. Thank You! http://crisbertcualteros.page.tl