1. Name That Rhythm EMT-Intermediate W06

9. And you thought we wouldn’t review…..

10. Heart A & P Location Pieces, Parts Important Vessels Electrolyte Role Pulling apart waveforms

11. Valves & Vessels

12. Review of Important Vessels

13. The Components SA Node Internodal Pathways AV Junction AV Node Bundle of His L & R Bundle Branch Purkinje Network Purkinje Fibers

14. The Route

15. Sino Atrial Node The Natural “Pacemaker” –Connects directly to atrial fibers Fires 60-100 times per minute Wavelike Atrial Depolarization The P-Wave P-Wave P-R Interval Q- Wave.04 Sec 0.20 Seconds per 5 Boxes

16. AV Junction Receives impulses from SA Node via the Atrial Cells –An electrical funnel –Impulses hit at various times –Causes delay PR-I –Susceptible to blockage Path from A to V –Delivers impulse to the AV Node

17. Atrio-Ventricular Node Lies between the Atria and Ventricles Collects impulses from above Stimulates Ventricles If unstimulated –Intrinsic rate 40-60

18. Bundle of His / Left and Right Bundle Branches Distributes Impulses from the Node “The Ventricular Messengers”

19. Purkinje Network/Fibers Direct connection with ventricular tissue Intrinsic rate 20-40 if unstimulated P-Wave P-R Interval QRS Complex T-Wave

20. Electrical Conduction System Sympathetic-Thoracic/Lumbar Nerve –Norepinephrine HR, Contractility Parasympathetic-Vagus Nerve –Acetylcholine HR (Valsalva) Chronotropic-HR Inotropic-Contraction

21. Electrical Conduction System Na + in & K + out = Depolarization K + in & Na + out = Repolarization –Imbalances in K + or Na + Effects Automaticity & Conduction Hypo & hyperkalemia affects irritability Ca ++ - Depolarization and Contraction –Affects Contractility –Hypo & Hypercalcemia effects contractile force

22. Phases Phase 0 – Rapid Depolarization –Reached max potential -90mV –Fast Na + Channels Open –Cell now positive +25mV Phase 1 – Early Rapid Repolarization –Fast Na + Channels Close –K + still being lost –MP approaching 0mV Phase 2 – Prolonged Slow Repolarization –Plateau Phase –Muscle finishing contraction –Beginning to relax –MP staying close to 0mV

23. Phases Phase 3 – End of Rapid Repolarization –K + returns to inside –Cell returns to -90mV –Almost ready Phase 4 –Na + - K + Pump turns on Sends Na + out Brings K + in Ready to do it all over again now

24. Refractory Periods Excuse me!!! I hate to interrupt again, but, who cares??? Absolute Refractory Period –Polarity of cell prohibits depolarization Relative Refractory Period –Cell is returning to ready state for depolarization –Impulse now is BAD!!! R on T Phenomenon –Causes VT & VF –Treated with defibrillation Can be caused by: –Frequent PVC’s –EMT-P not pushing the “sync” button

25. QRS Complex

26. Lead Considerations $25,000 mVoltmeter –Lead Views: 1 – Lateral 2 – Inferior 3 – Inferior

27. The Six Step Approach What is the Rate? Is the Rhythm Regular? Are there P-Waves? Is the P-R Interval Normal? Is the QRS Complex Normal? Is There a P-Wave for Every QRS?

28. Describe What You’ve Found!!! IN GENERAL (underlying rhythms)!!! What are the abnormalities? Does it originate in the Sinus Node? Does it follow through from the Atria to the ventricles? Are there abnormal delays? What are the exceptions to the underlying rhythm? (Describe those also)

29. Normal Sinus Rhythm Rate: 60 - 100 Regularity: Very P-Waves: Present and Normal P-R I: 0.12-0.20 sec QRS: 0.04-0.12 sec and Normal Married: 1 P: 1 QRS, no extras or shortages

30. Sinus Arrhythmia n Rate: 60 - 100 n Regularity: Irregular n P-Waves: Present and Normal n P-R I: 0.12-0.20 sec n QRS: 0.04-0.12 sec and Normal n Married: 1 P: 1 QRS, no extras or shortages

31. Sinus Tachycardia n Rate: Over 100 n Regularity: Regular n P-Waves: Present and Normal n P-R I: 0.12-0.20 sec n QRS: 0.04-0.12 sec and Normal n Married: 1 P: 1 QRS, no extras or shortages

32. Sinus Bradycardia n Rate: Less than 60 n Regularity: Regular n P-Waves: Present and Normal n P-R I: 0.12-0.20 sec n QRS: 0.04-0.12 sec and Normal n Married: 1 P: 1 QRS, no extras or shortages

33. Atrial Fibrillation n Rate: Usually tachy n Regularity: Irregular (Irregularly irregular) n P-Waves: Not Discernible n P-R I: Undeterminable n QRS: 0.04-0.12 sec n Married: Undeterminable

34. Atrial Flutter n Rate: Usually tachy n Regularity: Atria Regular Ventricles May be Irregular n P-Waves: Sawtooth Pattern 2:1, 3:1, 4:1... n P-R I: 0.12-0.20 sec on conducting beat n QRS: 0.04-0.12 sec n Married: P-waves outnumber QRS n (Picket fence)

35. (Paroxysmal) Supra Ventricular Tach n Rate: 140-220 n Regularity: Regular n P-Waves: Usually falls within the QRS-T complex (not visible) n P-R I: Shorter than 0.12, or absent n QRS: 0.04-0.12 sec and Normal n Married: Undeterminable

36. SVT WPW –Usually based on Hx. –Delta wave on Q –Shortened PR-I –No Verapamil – Accessory Path use increase

37. 1st Degree Heart Block n Rate: 60 - 100 n Regularity: Very n P-Waves: Present and Normal n P-R I: Longer than 0.20 sec n QRS: 0.04-0.12 sec and Normal n Married: 1 P: 1 QRS, no extras or shortages

38. 2nd Degree Heart Block (Type 1) Wenkebach n Rate: Can be Normal, or usually brady n Regularity: Irregular n P-Waves: Present and Normal n P-R I: Lengthens until beat is dropped n QRS: 0.04-0.12 sec and Normal n Married: P-wave present on conducting beats, increased delay causes missed QRS

39. 2nd Degree Heart Block (Type 2) Mobitz II n Rate: Less than 60 n Regularity: Irregular n P-Waves: Present, 2:1, 3:1, 4:1 n P-R I: 0.12-0.20 sec on conducting beat n QRS: 0.04-0.12 sec, may begin to widen n Married: P-wave for every QRS and extras depending on conduction ratio

40. 3rd Degree Heart Block (CHB) Complete Heart Block n Rate: Ventricular Rate 40-60 n Regularity: Atria-Regular Vent-Regular n P-Waves: Present and Normal n P-R I: Atria independent of Ventricles n QRS: Usually greater than 0.12 sec n Married: P-waves completely unrelated to QRS Complexes.

41. Complete Heart Block

42. Junctional Rhythm n Rate: 40-60 n Regularity: Regular n P-Waves: Inverted, Retrograde or Absent n P-R I: Shortened or absent n QRS: 0.04-0.12 sec n Married: P-wave for every QRS, sometimes not visible

43. Junctional

44. Junctional Accelerated Rhythm n Rate: 60-100 n Regularity: Regular n P-Waves: Inverted, Retrograde or Absent n P-R I: Shortened or absent n QRS: 0.04-0.12 sec n Married: P-wave for every QRS, sometimes not visible

45. Junctional Tachycardia n Rate: 100-140 n Regularity: Regular n P-Waves: Inverted, Retrograde or Absent n P-R I: Shortened or absent n QRS: 0.04-0.12 sec n Married: P-wave for every QRS, sometimes not visible

46. Ventricular Tachycardia n Rate: 100-220 n Regularity: Regular n P-Waves: None n P-R I: None n QRS: Greater than 0.12 sec n Married: NO We’ll look at Torsades de Pointes in Lab

47. Ventricular Tachycardia

48. Ventricular Fibrillation n Rate: No ventricular rate n Regularity: Irregular n P-Waves: No n P-R I: No n QRS: No, unorganized ventricular baseline n Married: No

49. Ventricular Fibrillation

50. Asystole n Rate: 0 n Regularity: N/A n P-Waves: None n P-R I: N/A n QRS: None n Married: No (verify a second lead)

51. Asystole

52. Agonal / Idioventricular n Rate: 20-40 n Regularity: Irregular n P-Waves: None n P-R I: N/A n QRS: Wider than 0.12 sec n Married: NO (a dying heart)

53. Idioventricular Less regular than this!

54. Exceptions / Disruptions Premature Ventricular Contractions Premature Atrial Contractions Bundle Branch Blocks Pacer Considerations (Atrial, Ventricular or Both)

55. Premature Ventricular Contractions Wide, Bizarre QRS Complex Always identify the underlying rhythm first Can appear in couplets, triplets, short runs of V-Tach, bigeminy and trigeminy Can be uni-focal or multi-focal Caused by random firing within the ventricles Not accompanied by a P-wave

56. PVC’s

57. PAC’s P-QRS Complex appearing in an unexpected location Caused by a stimulus from within the Atria, but not from the SA Node

58. PJC

59. Bundle Branch Block Any rhythm having a BBB will have a widened twin peaked R-Wave

60. Paced Rhythms Patients may have various types of pacemakers Atrial Ventricular Both Vertical spike on monitor is an indicator

61. Paced Rhythms Various

62. Artifact 60 Cycle Interference Loose Leads/Moving Ambulance

63. In Summary Really Cool Physiology!!! GENERAL RULES to Interpretation –Applicable to 3 – lead monitoring Practice, Practice, Practice… Remember the rules, NOT how it looks coming from one patient or one rhythm generator!!!

64. Sources – In order of preference Many of the pictures and info from: –Flip and See ECG, 2 nd Edition Cohn/Gilroy-Doohan –A great resource –Paramedic Paramedic Textbook, Revised 2 nd Edition Mick J. Sanders, Mosby –ECG’s Made Easy, 2 nd Edition Barbara Aehlert, RN, Mosby –Basic Dysrhythmias, Interpretation and Management, 3 rd Edition Robert J. Huszar, Mosby