1 / 76

Catheter Ablation in the Treatment of Atrial Fibrillation

Catheter Ablation in the Treatment of Atrial Fibrillation . Atrial Fibrillation. First described in 1903 by Hering Most common sustained arrhythmia. Atrial fibrillation accounts for 1/3 of all patient discharges with arrhythmia as principal diagnosis. 6% PSVT. 6% PVCs. 18% Unspecified.

torie
Download Presentation

Catheter Ablation in the Treatment of Atrial Fibrillation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Catheter Ablationin the Treatment ofAtrial Fibrillation

  2. Atrial Fibrillation • First described in 1903 by Hering • Most common sustained arrhythmia

  3. Atrial fibrillation accounts for 1/3 of all patient discharges with arrhythmia as principal diagnosis • 6% PSVT • 6% PVCs • 18% Unspecified 2% VF • 4% Atrial Flutter • 9% SSS • 34% Atrial Fibrillation • 8% Conduction Disease • 10% VT • 3% SCD Baily D. J Am Coll Cardiol. 1992;19(3):41A.

  4. Atrial Fibrillation • What is Atrial Fibrillation? • Chaotic circular impulses in the atria • Several reentrant circuits moving simultaneously • Atrial rates • 300 to 600 beats per minute • Ventricular rates regulated by the AV node • Irregularly irregular due to partial depolarization of AV node • Results in loss of AV synchrony • 20% to 30% decrease in cardiac output

  5. Incidence and Prevalence • Prevalence increases with age • 4.8 % in the 70-79 age group • Increases to • 8.8% in the 80-89 age group • During the next 7-8 years, the number of people over the age of 80 is expected to quadruple

  6. Atrial Fibrillation Demographics by Age U.S. populationx 1000 Population with AFx 1000 Population withatrial fibrillation 30,000 20,000 10,000 0 500 400 300 200 100 0 U.S. population <5 5-9 10-14 15-19 20-24 25-29 30-34 35-39 40-44 45-49 50-54 55-59 60-64 65-69 70-74 75-79 80-84 85-89 90-94 >95 Age, yr Adapted from Feinberg WM. Arch Intern Med. 1995;155:469-473.

  7. Stages of Atrial Fibrillation • Paroxysmal • Persistent • Permanent

  8. Stages of Atrial Fibrillation • Paroxysmal (23% of AF population) • Self limiting • Spontaneous conversion to sinus rhythm within 24 hrs after onset is common • Once the duration exceeds 24 hrs, the likelihood of conversion decreases • After one week of persistent arrhythmia, spontaneous conversion is rare • 30% of these patients develop “Persistent” AF

  9. Stages of Atrial Fibrillation • Persistent (38% of AF population) • Requires intervention to restore normal rhythm • Cardioversion • Electrical or Chemical (drugs) • Can lead to electrophysical and structural changes in the myocardium (remodeling) that can lead to “Permanent” AF • AF with duration of greater than 7 days rarely spontaneously converts

  10. Stages of Atrial Fibrillation • Permanent (39% of AF population) • Unable to convert Electrical or Chemical (drugs)

  11. Mechanisms of AF • Theories of the mechanism of AF involve 2 main processes: - Enhanced automaticity in one or several rapidly depolarizing foci - Reentry involving one or more circuits

  12. Mechanisms Contributing to AF

  13. Mechanisms of AF • Rapidly firing atrial foci, located in one or several pulmonary veins (PVs), can initiate AF in susceptible patients • Foci also can occur in RA and infrequently in the superior vena cava or coronary sinus

  14. Pulmonary Vein Myocardial Sleeves

  15. Factors Involved in the Pathogenesis of AF • Studies in man have shown that increased inhomogeneity of refractory periods and conduction velocity is present in AF patients. • Structural changes in atrial tissue may be one of the underlying factors for dispersion of refractoriness in AF. • Other factors involved in the induction or maintenance of AF include premature beats, the interaction with the autonomic nervous system, atrial stretch, anisotropic conduction, and the aging process, vein of Marshall……….

  16. Mechanisms contributing to AF

  17. Atrial Fibrillation: Clinical Problems • Embolism and stroke (presumably due to LA clot) • Acute hospitalization with onset of symptoms • Anticoagulation, especially in older patients (> 75 yr.) • Congestive heart failure • Loss of AV synchrony • Loss of atrial “kick” • Rate-related cardiomyopathy due to rapid and irregular ventricular response • Rate-related atrial myopathy and dilatation • Chronic symptoms and reduced sense of well-being

  18. Therapeutic Approaches to Atrial Fibrillation • Anticoagulation • Antiarrhythmic suppression • Control of ventricular response • Pharmacologic • Catheter modification/ablation of AV node • Curative procedures • Catheter ablation • Surgery (maze)

  19. Disadvantages High recurrence rate High long-term cost Non-curative Adverse effects Potential proarrhythmia Advantages High efficacy for somepatients, at leastinitially (< 50% of all patients) Low initial cost Noninvasive Antiarrhythmic Therapy for Atrial Fibrillation

  20. Antiarrhythmic Suppression • Drugs • Conversion of AF • Class 1A (decrease conduction velocity, increase refractory periods of cardiac tissue, suppress automaticity) • Quinidine • Procainamide • Class III (decrease conduction velocity, increase refractory periods of cardiac tissue, suppress automaticity) • Amiodarone • Sotalol • Ibutilide (Corvert) • Dofetilide

  21. Antiarrhythmic Suppression • Drugs • Maintenance of normal rhythm • Class 1A • Class III • Class 1C (decrease conduction velocity) • Flecainide • Propafenone • Drug choice depends upon patient’s underlying heart disease

  22. Nonpharmacological Approaches to Atrial Fibrillation Pacemaker therapy 2. Ablation 3. Surgery

  23. RF Ablation Techniques • Focal ablation of PV (Pulmonary vein) triggers • Segmental PV isolation • Wide Area Circumferential Ablation • Ablation of Fractionated Complex Electrograms • Targeted ablation of ganglionated autonomic plexi in the epicardial fat pads

  24. Focal Ablation of Triggers

  25. Focal Ablationof Atrial Fibrillation 95% of foci are located within a pulmonary vein ( PV). Focal sources of AF may be found in the RA, LA, coronary sinus, superior vena cava or vein of Marshall. Haissaguerre M, Jais P, Shah DC, et al. Spontaneous initiation of atrial fibrillation by ectopic beats originating in the pulmonary veins. N Engl J Med 1998;339:659–66. Chen SA, et. al: Initiation of atrial fibrillation by ectopic beats originating from the pulmonary veins: Electrophysiologic characteristics, pharmacologic responses, and effects of radiofrequency ablation. Circulation 1999;100:1879-1886.

  26. Pulmonary Vein Spike Discharges

  27. Pulmonary Vein Spike Discharges

  28. Initiation of AF by PV Discharges

  29. PV Potentials PV potentials

  30. PV Potentials

  31. PV Potential on 6-10

  32. PV potentials disappeared during radiofrequency current application

  33. Loss of PV Potentials

  34. Focal Ablation of Pulmonary VeinsComplications • The most common complications associated with the focal ablation of the PVs are pericardial effusion (<4%), transient ischemic episodes (<2%) and symptomatic PV stenosis <2%). • Asymptomatic PV stenosis may occur at as many as 40% of sites at which focal ablation is performed. • Symptomatic PV stenosis seems to be infrequent if the number of radiofrequency applications delivered within PV is kept to a minimum.

  35. PV Stenosis

  36. PV Stenosis

  37. Multi-slice CT Endocardial View

  38. PV Stenting

  39. Tamponade: Intra-cardiac echo The incidence of perforation during ablation of the left atrium is relatively low

  40. Segmental PV Isolation

  41. Segmental PV Isolation • Limitations associated with focal ablation have prompted the development of other techniques for eliminating the PV arrhythmias. • Anatomically PV isolation has significant advantages over focal ablation.

  42. Lasso or Spiral Catheters

  43. Dissociation of the PV potential after successful isolation

  44. Segmental Ostial Pulmonary Vein Isolation • The initial experience with segmental ostial ablation of PVs guided by PV potentials is encouraging, with a long-term success rate of 90% in patients with paroxysmal AF • Minimal risk of PV stenosis when the power of radiofrequency energy applications is limited to 30 W.

  45. Wide Area Circumferential Ablation

  46. Circumferential Ablation • It is an anatomic approach in which circumferential lines of block are created using 3D maps ( Carto, NavX..) around the ostia of PVs for isolation of PVs from LA. • Additional linear lesion from LIPV to mitral annulus for preventing LA incisional tachycardia ( 2%). • Additional linear lesions (posterior, roof, right isthmus….) may be created deepening on operator’s preference. Pappone C, et al. Atrial electroanatomic remodeling after circumferential radiofrequency pulmonary vein ablation: efficacy of an anatomic approach in a large cohort of patients with atrial fibrillation. Circulation 2001;104:2539–2544.

  47. NavX Map

  48. Anatomical Reconstruction of LA

More Related