1. Cardiac Rhythm

2. “Until the day Jesus returns, I will live in a body which does not function as God originally intended. My brain, which is a key, central, integral part of my body, will not function correctly. Chemicals will become imbalanced. Serotonin will not be properly absorbed. Norepinephrine will be unevenly distributed. Synapses won’t fire correctly. My brain, just like every other part of my body, is prone to illness.”

4. Sinus Rhythm - 6 second strip qrs times 10 = heart rayr

5. Sinus Rhythm

6. Atrial Fibrillation A-Fib – no p wave

7. Atrial Flutter – fluttering of p waves

8. Supra Ventricular – heart is beating fast and the heart can’t fill and the heart can’t pump

9. First Degree Atrioventricular block 1° AV Block – p waves are far away from qrs

10. Third Degree Atrio Ventricular Block 3° AV Block – p waves completely dissociated from qrs complexes

11. Ventricular Tachycardia V-Tach – qrs complexes are wide, one ventricle must be stimulating the other

12. Ventricular Fibrillation V-Fib VF – no qrs complexes, common rhythm in cardiac arrest

13. Cardiac Muscle Cell
The cardiac muscle cell can repeatedly contract or beat by itself

14. Cardiac Muscle Cell Na+ Ca2+ K+ Cl-
The cardiac muscle cell requires these ions and their membrane channel

16. Charged and Ready The Na+/K+ pump creates:
- sodium concentration gradient
- more outside than inside
- potassium concentration gradient
- more inside than outside
The Na/Ca pump creates
- calcium concentration gradient

17. Action Potential Step 1 sodium channels open
Sodium rushes in, causing a voltage change across the membrane

18. Action Potential Step 2 calcium channels open
Calcium rushes in, causing muscle contraction
Na channels are closing now

19. Action Potential Step 3 potassium channels open
Potassium ‘resets’ the membrane by rushing out until the membrane is charged and ready for another action potential

20. Cardiac muscle cell
Each separate cardiac muscle cell can repeatedly contract or beat by itself, at it’s own pace.

21. Fibrillation
When the cells beat separately and on their own, this is called fibrillation

22. Fibrillation
When the ventricles, the main pumps, are fibrillating there can be no heart beat

23. Synchrony
It is important that the cells work together

24. Conduction Pathway
Certain specialized heart muscles help conduct the signals and maintain synchrony

25. Conducting System of the Heart Picture

27. Atrio-Ventricular Node R-Atrium Picture

28. Sympathetic Neuron
NE – norepinephrine
Increased HR

29. Parasympathetic Neuron
Ach
Decreased HR

30. P wave – atrial excitation
- think of it as lighting the fuse
QRS wave – ventricular excitation
- think of it as the BANG!
T wave – ventricular repolarization
- think of it as the RESET

33. What do we do in V-fib?
Chest compressions is the first round of treatment for V-fib
100 beats/minute

34. Pulseless arrest BLS Algorithm: Call for help, give CPR
Give oxygen when available
Attach monitor/defibrillator when available
Allow for full recoil using chest compressions

35. Oxygen is a drug
- most important drug in pediatric arrhythmia
Use Bag valve mask or ambu bag

36. Bag Valve

37. Ambu Bag

38. VF/VT – pulseless Give 1 shock
Manual biphasic: device specific (typically 120 to 200J)
AED: device specific – automatic external defibrillator
Monophasic: 360J
Resume CPR immediately

39. Stand clear
Shock!

40. Fibrillation
By applying a large electrical shock sometimes we can convert fibrillation into a perfusing rhythm – synchrony
So must do chest compressions, oxygen, electricity

41. Defibrillation Applying a shock to the heart is called defibrillation
V-fib – oxygen is one of the greatest anti-arrhythmic drugs

42. Resume CPR immediately after the shock
When the IV is available, give vasopressin during the procedure (before or after the shock)
Epinephrine 1mg IV
Repeat every 3 to 5 mins or may give 1 dose of vasopressin 40IV to replace first or second dose of epinephrine

43. Epinephrine produces beneficial effects in patients during cardiac arrest primarily because of it’s α-adrenergic stimulating vasoconstrictive properties

44. Vasopressin – is a nonadrenergic vasoconstrictor
Vasopressin is also called Anti-Diuretic Hormone (ADH) and is released by the posterior pituitary of the brain

45. Resume CPR immediately after the shock
Consider antiarrhythimics, give during CPR (before or after the shock)
- amiodarone
- lidocaine

46. Lidocaine is a “Class 1” antiarrhythmic
It is a sodium channel blocker in heart muscle slowing down heart contraction

47. Amiodarone
Is a “Class 3” antiarrhythmic
It is a: sodium channel blocker, potassium channel blocker, calcium channel blocker, α & β adrenergic blocker

48. V-Fib interventions
Chest compressions
Oxygen
Shock!

49. V-Fib Drugs
Epinephrine
Vasopressin (ADH)
Lidocaine
Amiodarone

50. Do not confuse Ventricular fibrillation – cardiac arrest
Atrial fibrillation – the ventricles are still beating – will have a pulse, irregularly irregular ECG, will have tachycardia – you may call this as atrial fibrillation with rapid response

51. A-fib Major cause of strokes Major reason to give coumadin
Don’t want to convert A-fib to SR (sinus rhythm) until we know there is no thrombus

52. A-Fib
Stable
Unstable

53. Digoxin Lanoxin Digitalis glycoside
Blocks Na/K ATPase increasing calcium availability
Antiarrhythmic
Positive Inotrope
Negative Chronotrope
Slows AV conduction

54. Digoxin Risks
Arrythmia
Toxicity with hypokalemia

55. Supra Ventricular Tachycardia ECG Picture

56. SVT A-Fib RVR – rapid ventricular rate - Control ventricular rate
- Β-blockers (Class 2)
- Calcium channel blokcers (Class 4)
- verapamil
- diltiazem

57. Adenosine
Endogenous nucleotides which slows conduction through the AV node
IV antidysrythmic used in PSVT – paroxysmal supra ventricular tachycardia

58. SVT Adenosine - safe - “reset” AV node
- stops heart beat for about 6 secs
- 6 very long seconds……
Will not reverse a-fib a-flut

59. Atrial flutter – treat the same as a-fib

60. First Degree AV Block ECG Picture

61. Third Degree AV Block ECG Picture – p waves completely dissociated from qrs complexes

62. Bradycardia Bradycardia means low heart rate
Bradycardia is heart rate less than 60
Relative bradycardia means heart is beating too slow just to keep up with demand

63. Bradycadia
Stable
Unstable

64. Bradycardia
Atropine
- cholinergic blocker
Epinephrine
- adrenaline

65. Procaine – similar to Lidocaine
Procainamide
- sodium channel blocker
- watch for hypertension
- lupus-like adverse effects when taken chronically