Advancement of Catheter Ablation

With Magnetic Navigation

Caiyi Lu, Shenghua Zhou, Lei Gao, Qiao Xue

PLA General Hospital

Principles of Magnetic Navigation Technology

磁场强度： 0.08~0.10T；范围： 15~20cm

导管特点：含 1.8mm磁体 X3；柔软，可控

磁力线方向和大小 导管受力方向和大小

导丝特点：头端金冒，内含磁体

1. 3 维导航

2. 血管腔内导航

3. “ 牛眼”视图导航

4. “ 钟面”视图导航：

导航方式

导航图像的生成

整合 X 线血管造影机的二维图像，生成三维导航图像

整合 CARTO 图像到磁导航的导航图像中

整合 CT 或 MRI 图像，与造影图像结合，形成导航图像

Courtesy of San Raffaele University Hospital, Milan, Italy

Stereotaxis’ Semi-Automatic Cardiac Chamber Algorithm

自动生成三维导航图像

整合 CARTO图像形成导航图 Main Features

– Real-time Catheter Location on Navigant

– Fully Automated Mapping

– “Click and Go” Navigation on CARTO

– Send Carto Points/Lines to Navigant

– Catheter Contact Indicator

– CT Merge object integrated on Navigant

– Wand can be synchronized to CARTO

Navigation Controls on Carto

Integrated CT Merge object Under US 510(K) review. Not available in the US.

Comparison Between MNS and Mannual Procedure

MNS MANNUAL

Catheter

4mm regular magnetic

8mm regular magnetic

irrigated regular magnetic

Mapping bedside control room

Ablating bedside control room

Journal of the American College of Cardiology Vol. 42, No. 11, 2003

MNS and EPS

特点：定位精准，操作灵活，减少照射时间

Shortages of Manual Procedure

Instability of the ablation catheter Lower reproducibility Longer fluoroscopy time More ineffective energy delivery

Advantages of MNS Reduce fluoroscopic time Reduce RF lesion delivery Improved local contact Minimize fluoroscopic guidance Enhances catheter stability Improve clinical efficacy

MNS and AVNRT

Slow Pathway Was Mapped And Ablated By Magnetic Ablation Catheter

Parameter Comparison Between CMT and MNS

Slow and Fast JR during Energy Delivery

MNS and AVRT

Davis DR, et al. J Interv Card Electrophysiol. 2006, 16(3): 149-51

A case of a concealed parahisian AP Recurrence after 3 conventional ablation Successful ablation during a single RF lesion Total fluoroscopy time 17 min Asymptomatic during follow-up of 12 months

Ablation of Concealed Parahisian Accessory Pathway

1. The first case report of CAP ablation2. Key point is catheter stability during RF3. Minimized the risk of AV block

Cavotricuspid Isthmus Ablation in Pts With Common-Type Atrial Flutter (-)

1. 90 pts randomized to mannual (n45) or RMN (n45)2. Complete bidirectional isthmus block RMN 84%, Conventional 91%, P=0.523. RMN: Shorter fluoroscopy time: 10.6/15.0m,P=0.043 Longer RF application: 17.1/7.5m, P<0.0001 Longer ablation time: 55/17m, P<0.0001 Longer procedure duration: 114±35/ 77±24m,P<0.0001 Lower 6m f/u success: 73%/89%, P=0.063

Vollmann D, et al. Circ Arrhythm Electrophysiol. 2009 Dec;2(6):603-10.

MNS and Atrial Flutter

CON(n=45) RMN(n=45) Difference between means (95% CI)

P

Radiofrequency application duration, min

7.5 (3.6 ～10.9)

17.1 (8.6 ～25.1)

… ＜ 0.0001

No. of radiofrequency applications

9 (6 ～ 16) 22 (10 ～ 30) … ＜ 0.0001

Ablation time, min 17 (7 ～ 31) 55 (28 ～ 76) … ＜ 0.0001

Applied engery, w 54±10 59±11 4 （ 0 ～ 9） 0.047

Temperature ，℃ 51±4 50±4 -1 （ -2 ～ 1） 0.38

Impedance ， ohm 93±15 92±12 -2 （ -7- ～ 4） 0.58

Robotic vs Conventional Ablation for Common-type Atrial Flutter

• 50 pts (65.7 +/- 9.3 years) with AFL• Rrandomized to conventional or RNS• Bidirectional cavotricuspid isthmus block without

complications

Steven D, et al. Heart Rhythm. 2008, 5(11):1556-60

Procedural data comparison between both study groups

Conventional group 1

RNS group 2 P

Procedure duration, minutes 58.4 ± 17.7 79.4 ± 30.6 .04

Fluoroscopy time, minutes 8.2 ± 4.6 5.8 ± 3.6 .038

Fluoroscopy exposure time, minutes

8.2 ± 4.6 1.9 ± 1.1 .001

Preparation time, minutes 23.5 ± 9.1 45.4 ± 21.4 .001

RF energy, joules 16,308 ± 6870 8279 ± 5767 .001

RF duration, seconds 496.4 ± 213.9 321.7 ± 214.6 .006

• Safety and feasibility • Increased catheter stability• Increased RF application efficacy

Inferior Isthmus Mapping for Ablation of Typical Atrial Flutter

• 50 pts (58±11 years) with typical atrial flutter • Randomized to receive isthmus ablation

Group I (n24): conventionalGroup II (n26): magnetic

• Complete bidirectional isthmus block: Verified by double potential mappingGroup switch: not achieved by 20 RF or 25 min flu

• Results: Group I to II: 33%Group II to I: 4%Total fluoroscopy: 22.0±6.3 vs 3.9±1.5 m (P<0.0001)Fluo for isthmus mapping: 17.7±6.5 vs 0.2±0.3 min (P<0.0001)

• Conclusions: Significant reduction in exposure to fluoroscopyReduced to levels for diagnostic EPSMaintaining high efficacy

Kottkamp H, et al, Circulation. 2000;102:2082

Clinical Characteristics of Patients

Group I (n=24) Group II (n=26) P

Age, y 58.3±10.7 56.8±11.7 NS

Sex, male/female 19/5 21/5 NS

Structural heart disease, n (%) 16 (66.7) 18 (69.2) NS

Atrial flutter CL, ms 235±45 225±50 NS

Atrial enlargement on echocardiography, n (%)

11 (45.8) 13 (50) NS

MNS

CON

MNS And AT

Mehta R et al. Europace 2008;10:280-283

• 72y, Male

• History of CABG, mitral valvular repair, and prior RF

ablation for typical right AFL

• Daily occurrence of AT

• A single RF (43.8 , 27 W, 91Ω) resulted in prompt ℃

termination of AT

• Safety RF circumferentially surrounding success

site (total lesions 5, 236 s, 41.8 , 28 W, 88Ω)℃

A 12 lead ECG shows AT at ventricular rate of 100 beats/min

Mehta R et al. Europace 2008;10:280-283

Mehta R et al. Europace 2008;10:280-283

Mehta R et al. Europace 2008;10:280-283

Ventricular Arrhythmias Ablation: Comparison Between 4- and 8-mm Catheter Tips

• 65 pts with symptomatic VAs• 4mm to 8mm tip comparison• Succsess rate (4mm vs 8mm):

In CAD, IDC 22% vs 59% p=0.014In normal heart 85% vs 87% p=1.00

• Conclusion Increased success related to catheter tip RVOT origin, 4mm tip provided adequate lesions

Biase LD, et al. Journal of Interventional Cardiac Electrophysiology. 2009 ， 26 （ 2 ）：133

MNS and Ventricular Arrhythmias

Scar-Related Ventricular Tachycardia

• 27 procedures on 24 consecutive patients• VT related to: myocardial infarction dilated cardiomyopathy arrhythmogenic RV cardiomyopathy hypertrophic cardiomyopathy• Electroanatomic mapping Left ventricule 24 pts Right ventricule 10 pts Epicardial 12 pts• Fluoroscopy time for mapping Endocardial 27±23 s Epicardial 18±18 s• 97% VT were ultimately ablated• F/u: 7±3 m with VT free after 1.2 procedures /pt • Conclusions Safety and feasibility Minimal amount of fluoroscopy exposure

Aryana A,et al. Circulation. 2007;115:1191-1200

Ablation of Atrial Fibrillation

• 40 patients: 20 conventional 20 RMN • End point: PV entrance block• Procedure time: 279±60 vs 209±56 m, p<0.001• Fluoroscopy time: 58.6±21 vs 19.5±9.8 m, p<0.001• Conclusion: RMN is safe and feasible Similar clinical outcomes Decreased fluoroscopy and procedure times

Katsiyiannis WT, et al. The American Journal of Cardiology. 2008, 102(12):1674

MNS and Atrial Fibrillation

First Human Experience With An Irrigated-tip

Magnetic Catheter In Pts with Atrial Fibrillation

• Irrigated-tip magnetic catheter (Biosense Webster)• 29 pts (58.8±11.8 y) with symptomatic refractory AF• Power-control mode with a fixed power of 30 W• Endpoints: patient CPVA remotely catheter feasibility, safety and acute efficacy• Results Safe and success: 27/29 pts Total procedure time: 70.5±7.4 min Total ablation time: 30.7±7.1 min Impedance significantly decreased (p<0.0001) Maximum temperature: 36.4±0.8°C Follow-up: 6±2m with AF free in 27/29 pts • Conclusions 100% PV isolation Safe, feasible and effective Mitral isthmus block was easily achieved

Santinelli V, et al. Circulation.2008;118:984

Human Experience in Pulmonary Vein Ablation (-)

• 45 consecutive pts with AF• Stepwise approach: circumferential PV ablation (CPVA) pulmonary vein antrum isolation (PVAI) if failed, PVAI using conventional approach• End point: electrical disconnection of PVs• target location: 60% VS 100% conventional 8% could be electrically isolated 33% charring on the ablation catheter tip• Conclusions Remote magnetic system is a feasible technique Effective lesions cannot be achieved in most cases

Di Biase L, et al. J Am Coll Cardiol. 2007 Aug 28;50(9):868-74

Ablation Experience of Atrial Fibrillation

• 65 pts with refractory AF (43 paroxysmal, 22 persistent)• Acute complete PVI: 95%• Procedure time: 195±40 min• Operator x-ray time: - 6±4 min (35%)• F/u of 239 days, AF free in pts:

76% for paroxysmal AF

68% for and persistent

73% for any atrial tachyarrhythmia recurrences• Conclusions: PVI can be performed safely and effectively

30% of operator’s fluoroscopy be saved• Questions: whether pt fluoroscopy exposure is reduced

whether RN improves PVI quality

Boris Schmidt, et al. Circulation: Arrhythmia and Electrophysiology. 2009;2:120-128

LV Lead Implantation by 3D Image of CS

• 3D reconstruction of CS by using CardiOp-B system• Accuracy was evaluated by CS angiogram• Aims: Feasibility of deploying the guidewire LV lead into the selected side branch(SB)• Results: 16 pts were included Total fluoroscopy time: 23±14 min Fluoroscopy time to SB: 1.7±1.3 min• Conclusion 3D CS can be made using two angiographic views It allows magnetic navigation of guidewires in CS

Rivero-ayerza M, et al. Europace. 2008 ， 10 （ 9 ） 1042-6

MNS and LV Lead Implantation

164

28

100

144

24

83

0

30

60

90

120

150

180

(mi n)操作时间 (mi n)曝光时间 (%)成功率

MNS(n=9) (n=12)对照

Rivero-ayerza M, et al. Europace. 2008 ， 10 （ 9 ） 1042-6

总 结总 结

磁导航技术应用于心脏电生理介入治疗：安全、精确、有效 目前主要应用领域包括：

心脏电生理检查 心律失常射频消融 植入心脏起搏电极 心肌内注射治疗

临床应用研究尚处于起步阶段，缺乏大规模临床试验

Thank you for your attention