Catheter Ablation of Atrial Fibrillation Strategy and Outcome Predictors Shih-Ann Chen MD

Transcription

1 Catheter Ablation of Atrial Fibrillation Strategy and Outcome Predictors Shih-Ann Chen MD Taipei Veterans General Hospital, Taiwan

2 Outline of AF Ablation 1. Strategy for Catheter Ablation of AF 2. Substrate Ablation Guided by CFAE 3. CHADS2 Score and Long-term Outcome in Ablation of AF 4. Novel Ablation Devices

3 Strategy for Catheter Ablation of AF (Consensus Document HRS/EHRS/ECAS, 2007 and 2012 ) A. PV Isolation B. PVI, Roof line, mitral isthmus, CTI Make sure to complete isolation Complete line block C. PVI, Carina, RA, LA, SVCI D. DF and CFAE Find the residual PVP or non-pv ectopy AF substrate mapping

4 PVI is not enough for persistent AF ablation Persistent AF Paroxysmal AF 4 Parkash. JCE 2011 Favors CPVI+CFE Favors CPVI

5 We need CFAE! For Ablation of Persistent AF 5

6 Introduction The optimal substrate ablation approach is unclear in patients with Persistent (Per) and long-lasting Per AF (LS-Per) atrial fibrillation (AF). This prospective randomized study compared the efficacy of extensive atrial substrate modification versus limited atrial substrate modification after pulmonary vein isolation (PVI).

7 Ablation Strategy 120 msec N=99 N=70 N=29 Extensive CFE ablation 60 msec N=35 N=35 Limited CFE ablation

8 Patient Characteristics Variables Limited CFE (Group I), N=33 Extensive CFE (Group II), N=32 P value Age, year-old 54± 9 52± Male, N (%) 30 (88.2%) 27 (84.4%) 0.73 Long-lasting Per AF, N (%) 19 (55.9%) 17 (53.1%) >0.99 Hypertension, N (%) 19 (55.9%) 18 (56.3%) >0.99 Diabetes mellitus, N (%) 5 (14.7%) 1 (3.1%) 0.20 Coronary artery disease, N (%) 7 (20.6%) 7 (21.9%) >0.99 Congestive Heart Failure, N (%) 3 (8.8%) 7 (21.9%) 0.18 Structural heart disease, N (%) 0 (0.0%) 1 (3.1%) 0.49 Old stroke, N (%) 2 (5.9%) 4 (12.5%) 0.42 History of AF (month) 68± ±

9 Catheter Ablation Results

10 Primary Endpoint: All Atrial Arrhythmias Recurrence Single Procedure Multiple Procedure

11 Subgroup Analysis: AF Recurrence Ext. Persistent AF Long-Lasting Persistent AF Recurrence of AF was similar in persistent AF patients

12 Subgroup Analysis : Lt-AFL and AT Recurrence after Single Procedure Ext. LA-AFL, AT

13 Subgroup Analysis: AT & AFL Recurrence Ext. Persistent AF Long-Lasting Persistent AF Recurrent AFL required LA linear ablation in the repeat procedure (18% vs. 73% in Per and LS-Per patients, respectively, P=0.015).

14 Summary Pulmonary vein ablation plus limited substrate modification (continuous CFEs) is the optimal approach for persistent AF (< 1 yr in duration), with similar efficacy as extensive CFE ablation), and less recurrent AFL. Subgroup analysis showed that, in long lasting-per AF, extensive CFE ablation in both atria, and LA linear ablation might be necessary in the first ablation procedure.

15 Outline of AF Ablation 1. Strategy for Catheter Ablation of AF 2. Substrate Ablation Guided by CFAE 3. CHADS2 Score and Long-term Outcome in Ablation of AF 4. Novel Ablation Devices

16 Long-term Follow-up Paroxysmal AF

17 Total population N = 565 First procedure, N = 238 N = 105 Recurrence (+) Events rate = 15.2% (16/105) N= 121 N = 105 Recurrence (-) Events rate = 15.2% (16/105) N = 117 Recurrence-free rate = 49.2% Second procedure, N = 93 Recurrence (+) N = 47 Recurrence (-) N = 46 Recurrence-free rate = 68.5% Total population N = 565 Third procedure, N = 27 N = 105 Recurrence (+) Events rate = 15.2% (16/105) N = 14 N = 105 Recurrence (-) Events rate = 15.2% (16/105) N = 13 Recurrence-free rate = 73.9%

18 Recurrence free-survival curve after ablations of PAF (without AADs) A total of 238 PAF patients with a median follow up duration of 5 years. The minimal follow up duration was 2 years.

19 Table 2 Predictors of recurrence after ablation Variables Univariate analysis HR 95% CI P value Multivariate analysis* HR 95% CI P value Age (per year) Sex (male gender) Coronary artery disease CHADS 2 score < Body mass index (per kg/m 2 ) LA diameter (per mm) < LVEF (per percent) AF duration (per year) Presence of non-pv trigger Additional linear ablation * The multivariate analysis included variables whose p values were <0.05 in the univariate model.

20 Kaplan-Meier curves of recurrence in patients with different LA size

21 Kaplan-Meier curves of recurrence in patients with different scores

22 Different patterns of recurrences in patients with different CHADS 2 scores

23 Summary Patients with a high CHADS 2 scores were associated with high recurrence rate after PAF ablation. After a successful ablation, recurrences may continue to occur without reaching a plateau during the long-term follow-up, especially in patients with a high CHADS 2 score.

24 Long-term Follow-up Non-paroxysmal AF

25 Total population N = 565 First procedure, N = 88 N = 105 Recurrence (+) Events rate = 15.2% (16/105) N= 63 N = 105 Recurrence (-) Events rate = 15.2% (16/105) N = 25 Recurrence-free rate = 28.4% Second procedure, N = 41 Recurrence (+) N = 24 Recurrence (-) N = 17 Recurrence-free rate = 47.7% Total population N = 565 Third procedure, N = 6 N = 105 Recurrence (+) Events rate = 15.2% (16/105) N = 3 N = 105 Recurrence (-) Events rate = 15.2% (16/105) N = 3 Recurrence-free rate = 51.1%

26 Recurrence after ablation of non-paf A total of 88 non-paf patients with a median follow up duration of 2 years.

27 Cox regression analysis for predictors of recurrence Variables Long-standing persistent AF CHADS 2 score > 3 LA diameter (per mm) Univariate analysis* Multivariate analysis + HR 95% CI P value HR 95% CI P value Procedural termination *Variables with p values < in Table 1 were analyzed in the univariate Cox regression analysis. +The multivariate analysis included variables whose p values were <0.1 in the univariate model.

28 Different patterns of recurrence In patients with recurrence and CHADS 2 score > 3, all recurrences happened within 1 year after the procedure.

29 Recurrence-free survival curves in different groups of patients

30 Outline of AF Ablation 1. Strategy for Catheter Ablation of AF 2. Substrate Ablation Guided by CFAE and Linear/Non-linear Analysis 3. CHADS2 Score and Long-term Outcome in Ablation of AF 4. Novel Ablation Devices

31 Alternative ablation technologies for PVI Different devices (balloon technology, or mesh designs) have been studied, mostly in patients with paroxysmal AF without SHD or significant LAE. Mostly using radiofrequency current, some alternative energy sources, such as cryothermia, ultrasound, and laser energy. No better results compared to current sequential approach; but it is time saving! All of these devices still have to be shown the safety -- potentially causing excessive collateral damage such as atrio-oesophageal fistula formation.

32 Contact Force vs. Lesion Depth Endosense, TactiCath system provide contact force, low force predict recurrence Ensite Contact Technology: Provide electrical coupling index (ECI)

33 Real-time Image: Rotational Angiography 3D atriography is a novel intraprocedural 3D imaging technique. It can be safely and effectively used as a single navigation tool for performing PV isolation

34 Conclusion In non-paroxysmal AF, defragmentation is an important substrate ablation strategy The CHADS2 score is associated with longterm outcome after AF ablation

35 Welcome to Taiwan

36 CHADS 2 Score and Recurrence in PAF The CHADS 2 score is an important predictor of recurrence in the multivariate analysis with the HR of per increment of the score. Hazard ratio of recurrence: group 2 versus 1 = group 3 versus 1 = The CHADS 2 score is a convenient scoring system to predict the recurrence rate of PAF after catheter ablations Chao and Chen Heart Rhythm 2012 In press

37 Cardiac Echography Variables Left atrial diameter (mm) LV ejection fraction (%) LV end-systolic dimension (mm) LV end-diastolic dimension (mm) Baseline Limited CFE Extensive CFE P value 44.6± ± ± ± ± ± ± ± Abbreviation: LV=left ventricle

38 Cardiac Echo Follow-UP P < 0.01 P = 0.69

39 Meta-analysis of Additional CFE Ablation Paroxysmal AF patients (N=340) Non-Paroxysmal AF patients (N=360) Additional substrate modification Using CFE Ablation is Favor PVI along effective in patients with non-paroxysmal AF Favor PVI along Additional CFE ablation Additional CFE ablation Robert M. Hayward, et al. Heart Rhythm 2011

40 Mapping and Ablation Results Procedural variable Limited CFE Extensive CFE P value Incomplete procedure, N (%) 2 (5.7%) 3 (8.6%) 0.22 Non-Pulmonary vein triggers (including the first and repeat procedures, N [ %] ) 7 (20.6%) 9 (28.1%) 0.67 Procedure termination, N (%) 10 (29.4%) 14 (43.8%) 0.34 Procedure time (min) 193± ± 54.2 <0.01 Fluoroscopic time (min) 107± ± Pericardial effusion and other complications, N (%) 0 (0%) 0 (0%) 0.99

41 Outline of AF Ablation 1. Strategy for Catheter Ablation of AF 2. Substrate Ablation Guided by CFAE 3. CHADS2 Score and Long-term Outcome in Ablation of AF 4. Novel Ablation Devices

42 Target the Complex Fractionated Electrograms 121 patients (63 yrs, 57=PAF, 65=CAF). Target the CFAE of LA (mostly septum), RA and CS. Acute termination in 115/121 (95%), one year F/U 63 % without drug, 28 % with ibutilide, overall 91 % successful rate. Nademanee et al. JACC 2004

43 Variables Substrate Characteristics Left atrial substrate characteristics Limited CFE Extensive CFE P value Total activation time (msec) 132± ± Bipolar peak-to-peak voltage (mv) 1.12± ± Maximal DF during CFE (Hz) 25.8± ± Mean DF during CFE (Hz) 14.6± ± Mean of CFE (FI) 109± ± Right atrial substrate characteristics Total activation time (msec) 124± ± Bipolar peak-to-peak voltage (mv) 1.53± ± Maximal DF during CFE (Hz) 21.1± ± Mean DF during CFE (Hz) 13.0± ± Mean of CFE (FI) 124± ±

44 Cox regression analysis for predictors of recurrence Variables Univariate analysis Multivariate analysis HR 95% CI P value HR 95% CI P value Age (per year) Sex (male gender) Coronary artery disease CHADS 2 score < Body mass index (per kg/m 2 ) LA diameter (per mm) < LVEF (per percent) AF duration (per year) Presence of non-pv trigger Additional linear ablation

45 CHADS 2 Score and Recurrence in PAF During the follow up of 17.3 ± 7.0 months, 23.1% of the PAF pts suffered from recurrence. Group 1 : 2 : 3 = 13% : 27.6% : 45.9% Group 1: score 0 Group 2: score 1-2 Group 3: score > P value< 0.01 Gr o up 1 Gr o up 2 Gr o up 3 Gr o up 1 Gr o up 2 Gr o up 3 Chao and Chen Heart Rhythm 2012