cardiac arrythmias .my presentation (1) - Copy.pptx

cardiac arrythmias presentation

1. INTRODUCTION Arrhythmia is an abnormal rhythm of the heart. The only normal rhythm of the heart is a normal sinus rhythm. In this rhythm, an impulse is generated in the sinoatrial (SA) node, which is conducted through and slowed down while passing through the atrioventricular node (AV). It is then conducted through the bundle of His, to the left and right bundle branches, and eventually into the Purkinje fibers. Any deviation from this conduction pathway results in arrhythmia.

2. DEFINITION The term "arrhythmia" refers to any problem in the rate or rhythm of a person’s heartbeat. During an arrhythmia, the electrical impulses may be too fast, too slow or erratic causing an irregular heartbeat. - American Heart Association,2023

3. Dysrhythmia is a disorder of the formation or conduction of the electrical impulses within the heart. - Hariprasath ,2023

4. EPIDEMIOLOGY The prevalence of arrhythmias is expected to be 1.5% to 5% in the general population, with atrial fibrillation being the most common.  Arrhythmias may or may not produce any symptoms and can be paroxysmal, leading to difficulty in estimating true prevalence. The overall presence of arrhythmia is associated with higher morbidity and mortality.  Cardiac arrhythmias are thought to contribute to a significant proportion of cardiovascular disease burden in LMICs. T he incidence of heart block, sudden cardiac death, or tachyarrhythmia in large parts of Africa, Eastern Europe, and Central Asia.  The worldwide prevalence of third-degree heart block is estimated to be 0.04%. 6  It is estimated that 2.5 million people die annually due to lack of access to pacemaker implantation.

5. MECHANISM OF CONDUCTION Normal Bradycardia Tachycardia Flutter Fibrillation Premature complexes Blocks

6. CAUSES OF DYSRHYTHMIAS Cardiac conditions Cardiomyopathy Conduction defects Myocardial cell degeneration Accessory pathways Myocardial infarction Heart failure Valvular diseases

7. OTHER CONDITIONS Acid-base imbalance Alcohol Caffeine, Tobacco Connective tissue disorders Drug effects ( e.g. Beta blockers, toxicity) Electric shock Electrolyte imbalance Emotional crisis Herbal supplements

8. Cont … Herbal supplements Hypoxia Shock Metabolic conditions ( eg.thyroid dysfunctions) Near drowning Poisoning

9. CLASSIFICATION OF ARRYTHMIAS ABNORMAL HEART PULSE FORMATION Sinus arrythmias Atrial arrythmias Atrioventricular junctional arrythmia Ventricular arrythmia ABNORMAL HEART PULSE CONDUCTION Sinus-atrial block Intra-atrial block Atrioventricular block Intraventricular block

10. ARRYTHMIAS ORIGINATING IN THE SA NODE Sinus bradycardia Sinus tachycardia Sinus arrest Sinus arrythmias Sinus exit block Sick sinus syndrome

11. RHYTHMIAS ORIGINATING IN ATRIA Premature atrial contraction Atrial tachycardia Paroxysmal supraventricular tachycardia Supraventricular tachycardia Atrial flutter Atrial fibrillation

12. RHYTHMIAS ORIGINATING IN THE AV JUNCTION Premature junctional complexes Junctional rhythm and junctional tachycardia RHYTHMS ORIGINATING IN THE VENTRICLES Premature ventricular contraction Accelerated Idioventricular rhythm Ventricular tachycardia Ventricular fibrillation Asystole

13. ECG CHARACTERISTICS Rate : < 60/mt Rhythm : Regular P wave : Precede every QRS complex PR interval : Normal ( 0.12-0.20 sec) QRS complex : Normal ( 0.40-0.10 sec) Conduction : Normal TREATMENT Inj.Atropine Pace maker implantation

14. ECG CHARACTERISTICS Rate : >100 bt/mt Rhythm : Regular P wave : Precede every QRS complex PR interval : Normal ( 0.12-0.20 sec) QRS complex : Normal ( 0.40-0.10 sec) Conduction : Normal

15. SINUS ARREST Occurs when SA node automaticity is depressed and impulses are not formed absence of p wave to occur at expected time Unless there is escape of junctional or ventricular pacemaker the QRS complex also missing Sinus pause_ absence of one sinus impulse Sinus arrest_ absence of more than one sinus impulse ( pause of 3 seconds or more).

16. ECG CHARACTERISTICS Rate : Normal/bradycardia , atrial > ventricular beats Rhythm : Irregular P wave : Absent during sinus block/arrest if present Precede every QRS complex PR interval : Normal ( 0.12-0.20 sec) In junctional escape beats PR shorter QRS complex : Normal ( 0.40-0.10 sec); absent during sinus arrest Conduction : Normal when SA node firing Absent When SA node is not firing Junctional escape beat_ ventricular conduction normal Ventricular escape beat _ ventricular conduction abnormally slow

17. SINUS EXIT BLOCK Occurs when the impulse is formed in the sinus node normally but fails to excite atrial tissue. Types First degree SA block Second- degree Sa Exit Block Type I Second- degree Sa Exit Block Type II Complete Sinus Exit Block

18. COMPLETE SINUS EXIT BLOCK Occurs when no impulses reach atria from SA node and no p wave occurs Asystole or cardiac arrest occurs when junctional or ventricular pacemakers not take over the duty of SA node

19. RHYTHMS ORIGINATING IN ATRIA

20. ECG CHARACTERISTICS Rate : 100- 300 bt/mt Rhythm : Regular P wave : Usually not visible , buried in T wave PR interval : Cannot be seen QRS complex : Usually narrow Conduction : Normal, unless bundle branch block is present .

21. PAROXYSMAL SUPRA VENTRICULAR TACHYCARDIA Dysrhythmia originating in an ectopic focus anywhere above the bifurcation of bundle of his. Paroxysmal refers to an abrupt onset and termination sometimes followed by brief period of asystole.

22. If physical manoeuvres have not been successful IV Adenosine 6mg bolus , if no response within 1-2 minutes 2 nd & 3 rd dose of 12mg should be given. If adenosine fails, second line medications include D iltiazem (0.25 mg/kg IV loading dose followed by 5mg/ hr to 15 mg/ hr infusion), E smolol (0.5 mg/kg IV loading dose , then 0.5 mg/kg/min up to 0.2 mg/kg/min, will need to repeat bolus for every up-titration), M etoprolol (2.5 mg to 5 mg IV every two to five minutes , not to exceed 15 mg over 10 to 15 minutes). 

23. ATRIAL FLUTTER Originates from a SINGLE ECTOPIC focus in the right atrium, identified by recurring regular saw tooth shaped FLUTTER waves Palpitation, signs of reduced coronary and peripheral perfusion ATRIAL FIBRILLATION Originates from a MULTIPLECTOPIC focus in the right atrium, identified by FIBRILLATORY waves Symptoms of pulmonary congestion, Symptoms of inadequate coronary and peripheral circulation and systemic embolism.

24. MEDICATIONS B lood thinners to prevent blood clot formation or treat an existing blood clot. Examples include: Warfarin Other Food and Drug Administration-approved anticoagulants such as dabigatran, rivaroxaban, edoxaban and apixaban (direct-acting oral anticoagulants) Aspirin (in rarer cases) Heart rate-controlling medication Beta blockers Calcium channel blockers Digoxin

25. HEART RHYTHM-CONTROLLING MEDICATIONS T wo types of channel blockers for controlling the heart’s rhythm: Sodium channel blockers  help the heart's rhythm by slowing its ability to conduct electricity. Examples may include: Flecainide Propafenone Quinidine Potassium channel blockers  help the heart’s rhythm by slowing down the electrical signals that cause AFib. Examples may include: Amiodarone Sotalol Dronedarone

26. Electrical cardioversion   involves applying an electrical current to the heart to restore the heart's rhythm. The electrical current is delivered by paddles on a device called a defibrillator. Initial cardioversion-200J And then 360J and 360J.

27. COMMON TYPES OF ABLATION FOR AF INCLUDE Pulmonary vein isolation ablation (PVI ablation or PVA) AV node ablation with pacemakers SURGICAL PROCEDURES Pacemakers A pacemaker is a small electrical device implanted in the body, with wires going to the heart to regulate the heartbeat. It is implanted under the skin near the collarbone and sends out an electrical signal to keep a steady contracting rhythm in the heart. Some pacemakers sense when the heartbeat is too fast or too slow and then fire impulses that help the heart return to the proper rhythm and speed.

28. OPEN-HEART MAZE PROCEDURE Maze heart surgery is a complex procedure in which a surgeon creates small cuts in the upper part of the heart. Stitching the cuts together forms scar tissue. The scar tissue interferes with the transmission of the electrical impulses that can cause  atrial fibrillation , which restores a normal heartbeat.

29. RHYTHMS ORIGINATING IN THE ATRIOVENTRICULAR JUNCTION Cells surrounding the AV node in the AV junctional area have automaticity and are capable of initiating impulses and controlling the heart rhythm. Premature junctional complexes (PJC) Junctional rhythm Junctional tachycardia

30. RHYTHMS ORIGINATING IN THE VENTRICLES Premature ventricular contractions Accelerated idioventricular rhythm Ventricular tachycardia Ventricular fibrillation PREMATURE VENTRICULAR COMPLEX It is a contraction originating in an ectopic focus in the ventricles It is premature occurance of a QRS complex which is wide and distorted in shape compared with a QRS complex initiated from the normal conduction pathway

31. ECG CHARACTERISTICS Rate : 60-100bt/mt or the rate of the basic rhythm Rhythm : Irregular P wave : Not related to the PVCs ,Sinus rhythm is often not interrupted PR interval : Absent before the PVCs, If present PR interval is short. QRS complex : Wide and Bizarre, usually greater than 0.12 second in duration Conduction : Conduction in the ventricular myocardium is from muscle cell to muscle cell rather than through purkinjie fibers , resulting Wide QRS .

32. COUPLET /PAIRED PVCS

33. ACCELERATED IDIOVENTRICULAR RHYTHM Occurs when an ectopic focus in the ventricles fires at a rate of 50- 100bt/mt Commonly occurs in the presence of inferior MI and during reperfusion with thrombolytic therapy, when the rate of ectopic ventricular pacemaker exceeds the rateof sinus node. Usually not required treatment unless the patient is symptomatic

34. ECG CHARACTERISTICS Rate : 50-100bt/mt Rhythm : Usually regular P wave : May be seen ,but dissociated from QRS, If retrograde conduction to atria occurs , p wave follows QRS complex. PR interval : Absent QRS complex : Wide and Bizarre, usually greater than 0.12 second in duration Conduction : Conduction in the ventricular myocardium is from muscle cell to muscle cell rather than through Purkinje fibers, resulting Wide QRS.

35. VENTRICULAR TACHYCARDIA Ventricular tachycardia is 3 consecutive ventricular beats at a rate 120 beats/minute. Symptoms depend on duration and vary from none to palpitations to hemodynamic collapse and death. Diagnosis is by electrocardiography. Treatment of more than brief episodes is with cardioversion or antiarrhythmics, depending on symptoms. If necessary, long-term treatment is with an implantable cardioverter defibrillator.

36. DIFFERENT FORMS OF VT Monomorphic VT: Single abnormal focus or reentrant pathway and thus regular, identical-appearing QRS complexes Polymorphic VT: Several different foci or pathways and thus irregular, varying QRS complexes

37. Nonsustained VT: Lasts < 30 seconds Sustained VT: Lasts ≥ 30 seconds or is terminated sooner because of hemodynamic collapse Torsades de pointes : (Twisting of the points) is polymorphic VT associated with a prolonged QT interval of the underlying rhythm.

38. Treatment of Ventricular Tachycardia Hemodynamically stable ventricular tachycardia(with pulse) _ Inj.Amiodarone , Lidocaine Haemodynamically ,unstable ventricular tachycardia(with pulse) Cardioversion Pulseless ventricular tachycardia Defibrillation

39. INTRODUCTION Heart block is a problem with your heartbeat signal moving from the upper to lower part of your heart. The signal can only get through sometimes, or not at all. This makes your heart beat slowly or skip beats. People with second-degree or third-degree heart block may experience fainting, tiredness and shortness of breath. Other names for heart block are atrioventricular (AV) block or a conduction disorder.

40.   DEFINITION Heart block is an abnormal heart rhythm where the heart beats too slowly, which results in the electrical signals being partially or totally blocked between the upper chambers (atria) and lower chambers (ventricles). Heart block is also called atrioventricular (AV) block.   INCIDENCE Prevalence of chronic AV block is 2.47% per year In India with West Bengal tops the list with almost more than 70% prevalence, Assam with 10%, Bihar with 12.8%, Orissa 5% and Tripura with 2% prevalence.

41. Types of heart block Heart blocks can range from mild to severe, depending on whether the electrical signal can get through, and how often. Heart block types are: First-degree heart block :  The electrical impulse still reaches your ventricles, but moves more slowly than normal through the AV node. This is the most mild type of heart block. Second-degree (incomplete) heart block : With this type, your heart’s impulses only get to the lower chambers some of the time. The types of second-degree heart block are: Type I, also called Mobitz Type I or Wenckebach’s AV block :  This is a less serious form of second-degree heart block. The electrical signal gets slower and slower until your heart actually skips a beat.

42. Type II, also called Mobitz Type II :  While most of the electrical signals reach your ventricles, every so often, some don’t. Your heartbeat becomes irregular and slower than normal. This form of second-degree heart block is more serious and may warrant a pacemaker. Third-degree heart block:  This is a complete blockage of the electrical signal from your atria to your ventricles. Third-degree block negatively affects your heart’s ability to pump blood out to your body. This form of heart block is serious and usually requires a pacemaker for treatment.

43. FIRST DEGREE AV BLOCK Every impulse is conducted to the ventricles , but the duration of AV conduction is prolonged. Rate-60-100bt/mt ; Rhythm - Regular ;Conduction – Normal through atria Treatment – Usually not required. Slow in AV node. Slow in AV node.

44. SECOND DEGREE AV BLOCK MOBITZ I : Gradual lengthening of the PR interval followed by missed or blocked beat. ECG CHARACTERISTICS Rate : Atrial rate normal, Ventricular rate may be slower as a result of non conducted or blocked QRS complexes. Rhythm : Irregular unless 2:1 conduction is present. P wave : Normal, some p waves are not conducted to the ventricles, but only one at a time fails to conduct.

45. PR interval : Gradually lengthening of PR interval in consecutive beats. QRS complex : Usually normal unless there is associated bundle branch block. Conduction : Normal through atria and, progressively delayed through the AV node until an impulse fails to conduct. Ventricular conduction is normal. Conduction ratios can vary from low to high. Treatment If patient symptomatic_ Inj.Atropine is used If patient experience MI- Temporary pacemaker may be used.

46. Treatment- Pacemaker implantation .

47. SECOND DEGREE AV BLOCK ( MOBITZ II) PR interval is constant ( normal /prolonged), followed by a missed or blocked beat. ECG CHARACTERISTICS Rate : Atrial rate normal, Ventricular rate depends on degree of AV block Rhythm : Atrial rhythm regular but ventricular rhythm irregular P wave : Regular, precede each QRS, Periodically not followed by QRS complex. PR interval : Constant before all conducted beats QRS complex : Wide because of associated bundle branch block.

48. Conduction :Normal through atria and AV node, intermittently blocked in the bundle branch system and fails to reach the ventricles. Conduction through the ventricles is abnormally slow because of associated bundle branch block. Conduction ratio may vary from 2:1, 3;1, 4:1, 5:1 Treatment _ Pacemaker implantation.

49. THIRD DEGREE AV BLOCK Constitutes one form of Av dissociation in which no impulses from the atria are conducted to the ventricles. The atria are stimulated and contract independently of the ventricles. The ventricular rhythm is an escape rhythm and the ectopic pacemaker may be above or below the bifurcation of the bundle of His.

50. INFRA-HISIAN BLOCKS Infra hisian block is defined as an impaired conduction in the electrical system of the heart that occurs below the atrio ventricular node. Types • Type 2 second degree heart block (Mobitz II) –a type of AV block due to a block within or below the bundle of His • Left anterior fascicular block • Left posterior fascicular block • Right bundle branch block

51. INFRA-HISIAN BLOCKS Left anterior  fascicular block: Left anterior fascicular block (LAFB) is an abnormal condition of the left ventricle of the heart It is caused by only the anterior half of the left bundle branch being defective. It is manifested on the ECG by left axis deviation. It is much more common than left posterior fascicular block.

52. LEFT POSTERIOR FASCICULAR BLOCK : A left posterior fascicular block (LPFB), also known as left posterior hemiblock (LPH), is a condition where the left posterior fascicle, which travels to the inferior and posterior portion of the left ventricle,does not conduct the electrical impulses from the atrioventricular node. The wave-front instead moves more quickly through the left anterior fascicle and right bundle branch, leading to a right axis deviation seen on the ECG.

53. RIGHT BUNDLE BRANCH BLOCK (RBBB) A blockage of electrical impulses to the heart’s right ventricle. This is the lower-right part of the heart. During a right bundle branch block, the right ventricle is not directly activated by impulses travelling through the right bundle branch. The left ventricle, however, is still normally activated by the left bundle branch. These impulses are then able to travel through the myocardium of the left ventricle to the right ventricle and depolarize the right ventricle this way. As conduction through the myocardium is slower than conduction through the Bundle of Bundle of His-Purkinje fibres , the QRS complex is seen to be widened

54. Vagal maneuvers.   These are simple but specific actions that can slow the heart rate. They include coughing, bearing down as if having a bowel movement and putting an ice pack on the face. These actions affect the vagus nerve. The nerve helps control the heartbeat. Vagal maneuvers may be recommended if you have a very fast heartbeat due to supraventricular tachycardia. Vagal maneuvers don't work for all types of arrhythmias. Cardioversion.   Paddles or patches on the chest are used to give an electrical shock to the heart and help reset the heart rhythm. Cardioversion is typically used when vagal maneuvers and medicines don't work. Your healthcare team may recommend this treatment if you have a certain type of arrhythmia, such as atrial fibrillation.

55. Types of procedures and surgeries used to treat heart arrhythmias include: Catheter ablation.  In this procedure, the doctor places one or more catheters into blood vessels to the heart. Sensors at the catheter tips use heat or cold energy to create tiny scars in your heart. The scars block irregular heart signals and restore the heartbeat. Pacemaker.  If slow heartbeats don't have a cause that can be fixed, a pacemaker may be needed. A pacemaker is a small device that's placed in the chest to help control the heartbeat.

56. Implantable cardioverter-defibrillator (ICD).  This device is placed under the skin near the collarbone. It continuously checks the heart rhythm. If the device finds an irregular heartbeat, it sends out low- or high-energy shocks to reset the heart's rhythm. Maze procedure.  In the maze procedure, a surgeon makes tiny cuts in the upper half of the heart to create a pattern of scar tissue. The pattern is called a maze. The heart's signals can't pass through scar tissue. This treatment can block stray electrical heart signals that cause some types of fast heartbeats. The maze procedure is usually only done if you don't get better with other treatments or if you're already having open-heart surgery for another reason.

57. Coronary bypass graft surgery.  If you have severe coronary artery disease with an irregular heartbeat, you may need this type of heart surgery. The surgery creates a new path for blood to flow around a blocked or partially blocked artery in the heart.