CLINICAL OUTCOME OF AF ABLATION Who Benefits from Catheter Ablation?? Dr Gamal Shaban MD FESC Fellow of EHRA ECR AFA AFIB ALLIANCE NHI

Transcription

1 CLINICAL OUTCOME OF AF ABLATION Who Benefits from Catheter Ablation?? Dr Gamal Shaban MD FESC Fellow of EHRA ECR AFA AFIB ALLIANCE NHI

2 RHYTHM IS THE SOUL OF LIFE

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4 AF the last remaining challenge Considerable morbidity and mortality Recent developments in understanding of AF mechanisms

5 Therapeutic options

6 Mechanisms of AF Persistent Paroxysmal All atrial myocardium Underlying disease Anatomical/ electrical Remodeling Substrate Autonomic modulation Atrial stretch channels Other tachycardia Trigger

7 MetaElectrical Beyond being a focal electrical phenomenon Heterogenity of substrate and triggers Not All AF is the same What trigger the trigger???

8 Triggers vs Substrate in AF Paroxysmal Persistent Permanent Relative importance Trigger/ initiation Substrate/ maintenance AF duration

9 All AF is NOT the same

10 Approach to the AF Patient Rate control Elderly/frail Sx controlled Chronic? Rhythm control Paroxysmal Younger CHF/ stiff heart Treat HTN, lipids, DM, wt, exercise Diastolic dysfunction, systolic dysfunction, sleep apnea,? other

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12 Presumed Benefits of Rhythm Control Fewer symptoms/better exercise tolerance Diminished stroke risk Diminished need for anticoagulation Improved Survival But.

13 Limitations of Rhythm control Medication toxicity Asymptomatic arrhythmia/stroke risk

14 Primary Endpoint: All-Cause Mortality (%) Mortality Rhythm Rate P= Years Rhythm N: Rate N: CP

15 Conclusions Presumed benefits of maintaining sinus rhythm Fewer symptoms/better exercise tolerance Low risk of stroke Long-term anticoagulation not needed Better quality of life Better survival Outcome of patients in the rhythm control arm Functional status no different Similar rates of combined secondary endpoints, including stroke Most strokes (65/84) occurred off warfarin or with INR <2.0 Quality of life no different, but more hospitalizations No survival benefit; a trend toward increased late risk Affirm Investigators, ACC 2002

16 WHAT AFFIRM DOES NOT TELL US?? Optimal management for patients with moderate or severe disabling symptoms related to atrial fibrillation Outcome if better tools to maintain sinus rhythm were available Long-term implications of rate vs rhythm control (mean duration of follow-up only 3.5 years)

17 AFFIRM REVISITED 2 YEARS LATER 2004 AFFIRM Investigators The Presence of SR but not AADs use associated with lower risk of death These results suggest that if an effective method for maintaining sinus rhythm with fewer side effects it may improve survival

18 So why ablate? Our best drugs are only moderately effective Many patients despite adequate rate control remain symptomatic in atrial fibrillation Toxicities and side effects of medications Requirement for medication administration for 40+ years

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21 A New Idea Came Along Haissguerre et al. NEJM1998;339:659-66

22 Initiation and Maintenance of Atrial Fibrillation

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24 Pulmonary Vein Sleeves

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26 PV Potentials Modification Elimination After Abl 1 After Abl 6 End Abl HRA PV 1, 2 PV 2, 3 PV 3, 4 PV 4, 5 PV 5, 6 PV 6, 7 PV 7, 8 PV 8, 9 PV 9, 10 PV 10, 1 ABL dis Pulmonary vein CP

27 Ostial Location

28 NON-PULMONARY VEIN TRIGGERS AVNRT Left atrial posterior wall Crista Terminalis Eustacian Ridge/ CS Os region Mitral Valve Annulus Superior Vena Cava Fossa Ovalis/Limbus Para-Hisian Right Atrial Appendage Tricuspid Valve Annulus Ligament of Marshall

29 NON-PULMONARY VEIN TRIGGERS AVNRT Left atrial posterior wall Crista Terminalis Eustacian Ridge/ CS Os region Mitral Valve Annulus Superior Vena Cava Fossa Ovalis/Limbus Para-Hisian Right Atrial Appendage Tricuspid Valve Annulus Ligament of Marshall

30 Fibrillating Rhythm & Fibrillating protocols Especially in Permanent AF PVI PVAI WACA CPVI LACA Biatrial Ablation

31 Wide Area Circumferential Ablation: More than Trigger Elimination

32 AF-FREE SURVIVAL (%) SYMPTOMATIC AF-FREE SURVIVAL NO AAD, INITIAL PROCEDURE ONLY % (N=150) p < % (N=150) FOLLOWUP (MO) OSTIAL CIRC

33 Distribution of Atrial Ganglionated Plexuses Armour et al: Anat Rec 24:289, 1997

34 Publication date Nov. 28, 2001

35 Electrical remodeling Outside lesion (<0.1 mv): 0.8 ± 0.2 cm 2 PREABLATION POSTABLATION Inside lesion (<0.05 mv): 2.5 ± 0.9 cm 2

36 Quantification of the ablated area Average ablated area (4 PVs): 20 9% of total LA surface

37 PA PA ASI = 38.5% ASI = 7% RAO RAO

38 Multivariate Predictors of ASI* Clinical Parameter Persistent AF vs 11+8 LV EF < 50% 13+9 vs 8+4 P Value SHD vs * Stepwise linear regression

39 LA Scar and Late AF Recurrence 40 LA SCAR INDEX (%) NO RECUR 1 RECUR 2 3 RECUR 11+8 % 20+12% LASI > 18%: 5/10 (50%) LASI < 18%: 4/48 (8%) p = 0.005

40 Anatomical remodeling

41 circumferential PV ablation produces. Electrical remodeling of the PV-LA junction area (voltage reduction inside and outside the lesion) Atriovenous disconnection (PVPs and PV tachycardias abolition) Anatomical remodeling (LA size reduction)

42 LA reverse remodeling post ablation 1) Modest (10-15%) decrease in LA size when sinus rhythm is maintained, but not a return to normal size, even during extended periods of follow-up 2) Ongoing AF associated with little change in LA size or further enlargement 3) Despite decrease in LA size, LA contractile and reservoir functions remain abnormal, and significantly less than age-matched controls NORMAL SINUS RHYTHM, BUT NOT NORMAL ATRIUM

43 Cumulative probability of AF recurrence by Kaplan-Meier analysis Percent of patients with AF recurrence Paroxysmal AF 1 yr risk of recurrence 18% 11% Permanent AF Months from ablation 26% 2 yr risk 14%

44 Risk factors for AF recurrence by Cox regression analysis Univariate predictors AF duration (yrs) 2.0 P = 0.04 Permanent atrial fibrillation 2.5 P = Hypertension P = 0.09 Structural heart disease 2.6 P = Relative Risk of recurrence

45 Clinical Outcome at 1 year (672 patients) Patients free from AF 86% Paroxysmal 92%* Permanent 81%* *9% on AA drugs *10% on AA drugs

46 Heart rate variability and AF recurrence after circumferential PV ablation

47 Background Focal PV ablation can induce transient HRV alterations suggesting reversible autonomic dysfunction (sympathetic predominance) Circulation 1999; 100:

48 Substudy aim To investigate autonomic nervous system activity by HRV analysis after circumferential PV ablation

49 Evidence for local denervation after circumferential PV ablation Pre-RF Post-RF (6 mo) Reduced sympathetic tone Vagal predominance Pappone et al, ACC 2001

50 Circumferential ablation in the PV-LA region rich in endocardial nerve terminals is associated with persistent autonomic changes (denervation effect) Increased sympathetic and reduced vagal modulation of sinus node are found in pts with AF recurrence, suggesting that the shift of sympathovagal balance towards parasympathetic predominance may contribute to AF suppression.

51 AF ABLATION IN LVD/CHF Hsu et al, NEJM 2004; 351:237

52 CAN ABLATION IMPROVE SURVIVAL? Mean age yrs, 35% NSHD Pappone et al JACC 2003; 42:

53 RANDOMIZED TRIALS OF ABLATION FOR PAF STABILE (N=137) WANZI (N=70) JAIS (N=112) PAPPONE (N=198) ONE YEAR AF-FREE ABL AAD Major complications in 1-4% of ablation groups STABILE: EHJ : ; prior AAD failure; 1 episode/mo 6 mo duration; included 32% persistent AF; AAD given to ablation group; PVI+MI+CTI; blanking 1 mo; HM + 3 mo daily event montioring; endpoint 30 sec AF WANZI: JAMA 2005: 293: ); No prior AAD; 1 episode/mo 3 mo duration; PVAI; blanking 2 mo; HM + 1,3 mo event monitoring; endpoint 15 sec AF. Pilot study for RAAFT (400 pt trial) JAIS: HRS Scientific Sessions 2006; Prior AAD failure, 2 episodes/mo 6 mo duration; PVI+CTI+lines; blanking 3 mo; HM + symptom diaries; endpoint 3 min AF or palpitations PAPPONE: JACC 2006 in press, doi 10:1016. Limited prior AAD; 2 episodes /mo 6 mo duration;cpvi+cti+lines; blanking 6 wks, daily event monitoring; endpoint 30 sec AF

54 Persistent AF ablation vs drugs + CV AF lasting > 6months CPVA Up to 2 cardioversions in control group 3month blanking period 1 year event monitor Oral, NEJM 2006

55 Paroxysmal AF ablation vs drugs Drug resistant symptomatic AF PVI+CTI ± MI/Roof lines Up to 2 procedures in 90 day blanking period Failure >3min AF Jais, Circulation 2008

56 AF ablation : First Line Therapy? Untreated AF for 3mths 95% Paroxysmal 50% on beta blockers CPVA only 2mth blanking period Event recorder 1 year fu Wazni, JAMA 2009

57 Catheter ABlation Versus ANtiarhythmic Drug Therapy for Atrial Fibrillation (CABANA) Randomized trial comparing ablation to best drug therapy (rate or rhythm control) Primary endpoint: mortality (powered for 30% mortality reduction assuming 12% 3 yr mortality in drug group) Secondary endpoints: Composite (death, disabling stroke, serious bleeding, cardiac arrest) Freedom from AF recurrence (irrespective of symptoms) Health care costs and resource utilization Quality of life Planned 3000 pts, 120 enrolling centers Pilot phase approved starting late 2006, full study pending

58 Catheter ABlation Versus ANtiarhythmic Drug Therapy for Atrial Fibrillation (CABANA) Enrollment criteria > age 65, or < 65 with > 1 risk factor for stroke Eligible for both AF, and at least 2 membrane active drugs or 3 rate control drugs Paroxysmal (at least 2 episodes in prior 3 mo), persistent or chronic AF Ablation technique to include PVI + additional procedures (lines, CFAE, ganglionated plexi) 3 month blanking period in both groups (repeat ablation, or change in AAD permitted). Crossover to ablation in drug group strongly discouraged Followup with holter monitor, daily TTM (2 wks every 6 mo), and ILR (proposed 750 pt substudy)

59 Benefit from AF Ablation Desired Benefit Stopping anticoagulation Improve ejection fraction Improvement in symptoms Long-term cure Freedom from drug side effects Mortality decrease Result of Ablation If indication existed anticoagulation must continue Likely improvement but difficult to quantify in study Most important indication for ablation Unclear whether cure or control Likely but up to 30% with continued medication No demonstrated benefit on mortality at present

60 Who Benefits from Catheter Ablation of Atrial Fibrillation? The Ideal Patient Paroxysmal atrial fibrillation The Common Patient Chronic atrial fibrillation Valvular disease, Structurally normal heart cardiomyopathy Normal left atrial size Marked left atrial enlargement Younger patient Older patient, diastolic Palpitations, documented dysfunction correlation of symptoms Fatigue, questionable symptoms

61 But.. back in the real world In EG we have finite resources AFib ablations have to be managed alongside other ablations which are generally quicker, more effective, have less complications and are cheaper Should we try to run before we can walk, especially if there are other therapeutic options

62 Who should be offered ablation, here and now in EG? Patients with symptomatic, drug refractory atrial fibrillation, should be judged on an individual basis according to the Ablation Centre s experience Ideally, the patient should satisfy the following criteria: A rhythm control strategy is preferred and other therapeutic options are not as appropriate Attempts with at least 1 AAD have failed Preferably <70 (certainly <80!) Preferably normal heart or mild-moderate structural heart disease (LVEF>45%?) Preferably not a very dilated left atrium Prepared to accept risk of stroke (based on patient factors and institution s results) Prepared to accept failure (based on institution s results) Prepared to accept need for a re-do procedure (based on institution s results)

63 Who to refer. Symptomatic atrial fibrillation Paroxysmal or persistent Failed drug therapy No major cardiac structural abnormality Age <70 LA size <4.5 cm Willing to accept 1-2% risk of TIA or CVA Willing to undergo a 4-5 hour procedure Willing to accept 20-30% chance of 2 nd procedure Willing to accept 75-85% improvement rate, 40-50% cure rate off AA drugs for now

64 Points to remember Will need Warfarin 1 month before and minimum 3 months after procedure May require ongoing AA drug Rx AFib and LA flutter often occur in first few months after procedure. True success should be assessed after 3-6 months Permanent AFib may be considered, but?? success rate

65 Clinical Implications Chronic AF maybe a curable condition regardless of its duration or the presence of underlying heart disease.

66 PAPPONE 2009 ABLATION of AF is strikingly better than long term AADs, despite a limted incidence of a number of possible complications compared to potential benefits HOWEVER complications detection and management is dependent on case load Success rate is center dependent

67 KUCK AF Abl 2009 TO IMPROVE BENEFITS Effectiveness of RFC lesion creation Safety of RFCA vs other technologies New Energy sources for permanent PVI

68 KUCK AF ABL 2009 RCT : CA is superior to AADs WACA 3D guided is the gold standard of RFCA PVI to most pts with PAF whereas LA ablation is often necessary in persistent AF Real times contact force measurements improve lesion formation & incomplete lesions lead to recurrence Balloon based laser is the only visually guided tech producing permanent PVI

69 Clot control AF Rhythm control Rate control Treating a purely electrocardiographic disease

70 Atrial Fibrillation Ablation Evolution of the Moving Target Early Rumors (20 hr cases) Left Sided Focal Tamponade TIA/CVA WACA + Linear Esophageal Fistulas Left Atrial Flutters Hybrid Approaches Mid 90 s IVUS / Transeptal Lasso 3D Mapping CT integration 2006 Need for Stereotaxis, Cryoablation, HIFU? Right Sided Linear PV Isolation Fractionated Egms Phrenic Nerve Injury PV Stenosis Back to the Right Side The Trouble With a Moving Target

71 Atrial Fibrillation New Technology Coming Your Patients Way Stereotaxis Magnetic Catheter Navigation Energy Sources High Intensity Focused Ultrasound (HIFU) Cryoablation Balloon Watchman Left Atrial Appendage Closure

72 Pharmacologic therapy Targeted surgery AF Prevention Ablation Gene therapy Patient- & context-specific therapy

73 A-Fib vs. EP Labs