Catheter ablation of ventricular tachycardia

Catheter Ablation of Ventricular Tachycardia

Lin Yenn-Jiang MD. Chen Shih-Ann MD.April 15, 2012

Advanced EP training, St. Jude Medical, Taipei

Taiwan Heart Rhythm SocietyDivision of Cardiology, Taipei Veterans General Hospital

and National Yang-Ming University, Taipei, Taiwan

Experience of VT EPS/ABLin Taipei VGH 2001-2011

61%61%

12%12%

9%9%

9%9%

4%4%

2%2%

1%1%

1%1%

OT VTFVT

ARVC

CAD

DCM

P=0.007

Survival of VT Patients According to National Mortality Data Base of Taiwan (up to 2011)

CAD, DCMCAD, DCM

ARVCARVC

RV-VTRV-VT

Brugada,VFBrugada,VF

Fascicular VTFascicular VT

Different types of VTDifferent types of VT

Focal TypeFocal Type Reentrant TypeReentrant Type

Pace mapping, Activation map, Unipolar electrogram morphology

Entrainment technique, substrate mapping, Electrogram characteristics

Mapping and ablation VT differ by underlying condition and tachycardia mechanism.

Focal Ventricular Tachycardia

ICD Lead

LV apex

Septum

RVOT

Lin YJ et al. HRS abstract 2010

Reentrant Ventricular Tachycardia

How to Map VTTools

Surface ECG: origin, exitPace mappingEntrainment technique: during VT,3D activation and substrate mapping:

Stable VT: NavX, CartoUnstable VT: Ensite Array, substrate map during si

nus rhythm

Location: RV, LV, and EpicardiumECG, substrate map, activation map

Outlines

Outflow tract VT. ARVC/D.LV Fascicular VT.Papillary muscle VT.CPVT, BBRVT.Substrate VT: CAD, DCM.

Outflow Tract Ventricular Tachycardia (OT-VT)

VT arises from the right ventricular outflow tract (RVOT-VT, left ventricular outflow tract (LVOT-VT), aortic cusps (Cusp VT), and from the pulmonary artery (PA VT)

OT-VT tend to occur in the absence of structural heart disease and are focal in origin, the 12-lead ECG recorded during VT is a precise localizing tool.

Clinical Features of RVOT-VT

RVOT VT constitutes 75% of all patients with outflow tract VT

RVOT VT is more common in females 30-50 years old.

Symptoms include palpitations, dizziness, atypical chest pain, and syncope.

Exercise testing reproduces the patient’s clinical VT 25 to 50% of the time.

Mechanism of RVOT-VT

Most forms of RVOT VT are sensitive to adenosine

Most likely mechanism is catecholamine mediated DAD and triggered activity.

Mediated by the activation of cyclic AMP. Can be induced in the EP lab with isoprote

renol, aminophylline, atropine, and rapid burst pacing but rarely with programmed ventricular extrastimuli.

RVOT VTRVOT VT

IIIIIIaVRaVLaVFV1V2V3V4V5V6

1. Important overlapping nature of the outflow tract course!

2. RVOT and PA lie anterior and to the left of the LVOT and aorta.

Outflow Tract AnatomyOutflow Tract Anatomy

RVOT VT: Pace mapping ECG morphology

Pulmonary Artery VT

David Callans JCE 2009

Cross over of RVOT & LVOT region

AP viewAP view Superior viewSuperior view

RR

RR

LL

LL

I: biphasic, V1 :WI: biphasic, V1 :W

I: positive V1 :RSI: positive V1 :RS

AntAnt

RightRight

LeftLeft

How to D/D RVOT and VT with ASC in origin

LVOT and Aortic Cuspid VT VT arising from the LVOT shares similar character

istics to the RVOT VT because of a common embryonic origin.

ECG: LBBB with inferior axis with small R-waves in V1 and early precordial transition (R/S 1 by V2 or V3) or RBBB morphology with inferior axis and S-wave in V6.

Aortic cusp VT accounts for up to 21% of idiopathic VT.

More commonly arises from the LCC, than the RCC and rarely arise from the NCC.

Aortic Cusp VT Morphology

Tabatabaei and Asirvatham. Circ EP 2009;2:316-326

LVOT VT Morphology

Mapping Tool for OT-VT

ECG morphology Could be non-inducible

Pace mappingCould be large area 2 cm2: different chamber, scar, or epicardium,

Activation mapMore accurate: remain unsuccess: more mapping sites, epicar

dium, different energy sources,

Spontaneous 　 PVC 　　　　　 Pace　Mapping

Taipei VGH 2010

PVC Disappearance Just After RF

12

A BVT PM 1 PM 2

Free wall

Septal wall

Anterior wall

RVOT

Difficulty in Pace Mapping in RVOT-T (1)

Taipei VGH 2010

Schema of the Ventricular Arrhythmia Origin, BreakoSchema of the Ventricular Arrhythmia Origin, Breakout Site, and Preferential Conduction From the LCC to tut Site, and Preferential Conduction From the LCC to t

he RVOThe RVOT

T. Yamada, et al JACC, 2007, Vol. 50, No. 9: 884-91

Difficulty in Pace Mapping in RVOT-T (2)

Voltage of SR Spectral Analysis Activation of VT

RVOT-T : 3D mapping

Scar in the free wall site

3.5 cm from PV

Successful site

0.000

0.002

0.004

0.006

0.008

0.010

0.012

0.014

0.016

0.018

0 20 40 60 80 100 120 140 160 180 200 220 240 260 280 300

Free wall

septum

Eg during SR

Summery

Carefully ECG interpretation and EP study to Carefully ECG interpretation and EP study to

localize the optimum ablation site for VT.localize the optimum ablation site for VT.

Usually not life threatening, and could be treated Usually not life threatening, and could be treated

conservatively.conservatively.

3D mapping system can be helpful (activation 3D mapping system can be helpful (activation

map or substrate map), but correct chamber, far-map or substrate map), but correct chamber, far-

field sensing, preferential conduction need to be field sensing, preferential conduction need to be

consideredconsidered. .

Outlines

Outflow tract VT. ARVC/D.LV Fascicular VT.Papillary muscle VT.CPVT, BBRVT.Substrate VT: CAD, DCM..

Idiopathic RVOT-TIdiopathic RVOT-T

Right ventricular outflow tract tachycardia (RVORight ventricular outflow tract tachycardia (RVOT-T) represents up to 10% of all ventricular tachyT-T) represents up to 10% of all ventricular tachycardias (VTs), and is considered as a benign disecardias (VTs), and is considered as a benign disease.ase.

Symptoms:Symptoms: Ranging from none to palpitations, li Ranging from none to palpitations, lightheadedness, dyspnea, or syncope. ghtheadedness, dyspnea, or syncope.

Arrhythmias:Arrhythmias: Frequent isolated PVCs, bursts of n Frequent isolated PVCs, bursts of nonsustained VT, or sustained tachycardia often fonsustained VT, or sustained tachycardia often facilitated by catecholamines or exercise.acilitated by catecholamines or exercise.

Ablation:Ablation: Acute success rate of focal ablation of Acute success rate of focal ablation of RVOT-T is 65–97% with rare complications. RVOT-T is 65–97% with rare complications.

Arrhythmogenic RV DysplasiaArrhythmogenic RV Dysplasia Cardiomyopathy begins in RV with poor contractile fCardiomyopathy begins in RV with poor contractile f

unction and dilatation, progresses to LV finally.unction and dilatation, progresses to LV finally.

Histology:Histology: RV muscle becomes replaced by adipose RV muscle becomes replaced by adipose and fibrous tissue.and fibrous tissue.

Arrhythmia:Arrhythmia: Re-entrant Type (scarring & late Potentia Re-entrant Type (scarring & late Potentials) with LBBB type ECG; ls) with LBBB type ECG;

ECG:ECG: Diffuse T wave inversion over precordial leads, Diffuse T wave inversion over precordial leads, and Epsilon Wave. and Epsilon Wave.

Ablation:Ablation: The effect of catheter ablation is temporizin The effect of catheter ablation is temporizing, 1/3 epicardium, mostly reentry. Implanted cardioveg, 1/3 epicardium, mostly reentry. Implanted cardioverter defibrillator (ICD) is the only reliable therapy for rter defibrillator (ICD) is the only reliable therapy for sudden cardiac death.sudden cardiac death.

Task Force Criteria

TF (Definite +)TF (Definite +) if meet if meet 2 major 2 major or or 1 major 2 minor 1 major 2 minor criteriacriteria

McKenna et al. 1994, BMJ

TF Criteria

Positive TF criteria is important to diagnose Positive TF criteria is important to diagnose

ARVC/D and is specific to detect the future VARVC/D and is specific to detect the future V

F/ICD implantation/ CV mortality F/ICD implantation/ CV mortality

Malignant ventricular arrhythmia and late recMalignant ventricular arrhythmia and late rec

urrences may occur in patients with mild or urrences may occur in patients with mild or

atypical form of arrhythmogenic RV cardiomatypical form of arrhythmogenic RV cardiom

yopathy.yopathy.

ECG of End stage ARVCRVEF=10%, LVEF=15%

RV-VT, ARVC/D

Multiple VT morphology in ARVC/D

Sinus rhythm voltage map

Peri-valvular VT in a Patient with ARVC/D

Europace 2005Europace 2005

Electrophysiology

RVOT-TNot Fulfilling TF

(RVOT-VT)78.4%

Definite ARVC 21.6% P value

Catheter mapping

RV ERP (msec) 215 ± 22 238 ± 32 0.016

Inducible sustained VT 24% 59% 0.001

Requirement of isoproterenol infusion

53% 26% 0.016

Tachycardia cycle length (msec)

315 ± 67 277 ± 94 0.109

3D mapping

Scar in the RVOT (voltage <0.5 mV)

37% 57% 0.416

Scar in the RV body 47% 57% 0.697

Total RV conduction time (msec)

129 ± 46 222 ± 77 <0.001

Chen SA et al. 2011 HRS abstract

Factors VT

recurrence (+)

VT recurrence

(-)

Odds ratioCI (95%)

Multivariate analysis

P value

TF criteria (1 major one minor, or 3 minors)

35% 13%7.5

0.95-590.055

Substrate Mapping RV body & free wall scar

46% 17%5.9

1.02-340.047

Distance to the pulmonary valve (cm)

29±19 19±101.1

1.01-1.170.047

Predictor of VT Recurrence After Ablation in TF (-) Patients

The presence of Scar / Foci in FREE WALL indicated future recurrence in TF (-) patients

Chen SA et al. 2010 HRS abstract

P=0.511

All CauseAll CauseMortalityMortality

Malignant Malignant arrhythmiasarrhythmias

TF (+) , 7.4%

TF (-), 3.1%

P=0.019

TF (+): 36%:

TF (-) : 14%

Follow-Up Duration

Cumulative Incidence Cumulative Incidence

Follow-Up Duration

Long-Term Outcome(Mean follow-up time for more than 2 years)

Kaplan-Meier analysis of survival free of rapid VT/VF event in ARVC patients

Summery of ARVC/D

The most specific criteria to predict the outcome of ARThe most specific criteria to predict the outcome of AR

VC patients: VC patients: TF criteriaTF criteria. .

Detection of atypical and early form of ARVC from idiopDetection of atypical and early form of ARVC from idiop

athic RVOT-T: athic RVOT-T: Substrate mappingSubstrate mapping..

Substrate characteristics of ARVC: Diffuse LVZ and lonSubstrate characteristics of ARVC: Diffuse LVZ and lon

ger activation time, and abnormal substrate in the Epi-eger activation time, and abnormal substrate in the Epi-e

ndocardium; Tachycardia: both focal and reentrant.ndocardium; Tachycardia: both focal and reentrant.

Outlines

Outflow tract VT. ARVC/D.LV Fascicular VT.Papillary muscle VT.CPVT.Substrate VT: CAD, DCM, Brugada S.

LV fascicular VT

Most common left ventricular VTMost common left ventricular VT

Morphology: RBBB pattern (post. fascicular type: Morphology: RBBB pattern (post. fascicular type:

superior axis and LAD. incidence 90%; ant. fascicular superior axis and LAD. incidence 90%; ant. fascicular

type: inferior axis, and RAD; incidence 10%)type: inferior axis, and RAD; incidence 10%)

is a reentrant VT that originates from the Purkinje is a reentrant VT that originates from the Purkinje

network near the left ant or posterior fascicle without network near the left ant or posterior fascicle without

structural heart disease.structural heart disease.

This VT can be ablated by the diastolic potentials (P1 This VT can be ablated by the diastolic potentials (P1

or DP) or Purkinje potentials during VT.or DP) or Purkinje potentials during VT.

Posterior Fascicular VT

Diastolic potential & Purkinje potential

LPF

P1P2 (LPF)

LVSexit

100 ms

P2

P1 P1: antegrade limbLVS: retrograde limbP2 (LPF): bystander

A

H

A B

Posterior Fascicular VT

Where to Target

P1 (DP) in the mid-septum of LV (28-130 ms before QRS). The earliest P1 is not required, usually targeting the lower 1/3 of the P1 to avoid AVB.

If P1 could not be identified, target the fused and earliest P2 (PP) near the exit site of the tachycardia.

Perfect QRS match during pace mapping may not be required.

Anatomic-guided linear ablation, longitudinal transect the limb of FVT.

Conventional catheter is enough

Outlines


LV Papillary M VT (PM-VT)

Catecholamine sensitive VT, arising from anterior anCatecholamine sensitive VT, arising from anterior an

d posterior papillary muscle.d posterior papillary muscle.

Relative benign course in the follow-upRelative benign course in the follow-up

Focal and non-reentrant in mechanism. Mostly preseFocal and non-reentrant in mechanism. Mostly prese

nted with burst VPCs, Extra-stimulation induced VT nted with burst VPCs, Extra-stimulation induced VT

(-), entrainment (-).(-), entrainment (-).

Require advanced imaging to locate the PM-VT (angioRequire advanced imaging to locate the PM-VT (angio

graphy, TEE, ICE…)graphy, TEE, ICE…)

Could required Could required multiple site ablationmultiple site ablation and and irrigated RFirrigated RF

to achieve long-term success.to achieve long-term success.

Location of Ant. and post. PAP M

JCE, Vol. 20, pp. 866-872, August 2009

Surface ECG

NegativeNegative

Wide QRSWide QRS

Early transitionEarly transition

VPC SR

Intracardiac recording

ECG of Post. PAP VT

Circ Arrhythmia Electrophysiol. 2008;1:23-29

Heart Rhythm, Vol 5, No 11, November 2008

Differentiation of PM-VT and Fascicular VT

Outlines


Baseline EP characteristics: BBRVT

• BBRVT: Old patients , structure heart disease

• RBBB or LBBB,• Reentry: PPI<30 at RVap

ex, Critical delay of His-Purkinje system

• HV longer than SR, • HV during SR not normal

CPVTCPVT

Bidirectional VT, CPVTBidirectional VT, CPVT 3.　Activation　Mapping,　during　tachycardia　

ECG after ablationECG after ablation

Outlines


Substrate VT

Localization of chamber (RV, LV, or Epi)

Localization of the disease susbtrate..

Identify the circuits of VT/VF, potential exit/entrance sites for VT/VF, by activation/entrainment during VT/VF and substrate during SR.

Determination of the targets for ablation.

Strategy for SubstrateVT/VF ablation

Mappable/ inducible VT: Identification of the circuits and use of entrainment technique.

Unstable VT: substrate mapping during SR, use device, AAD to slow the VT rate.

Non-inducible VT: substrate mapping, pace mapping, consider autonomically or ischemically/mediated VT

Ineffective ablation: energy source, extensive ablation, or epi/intramural in origin.

1. Localization of VT by ECG

Bundle branch morphology: RBB: LV, LBB: RV or LV septum.

Superior and inferior axis: sup. and inferior LV

Precordial transition: dominant R: mitral to basal, dominant S: anterior apex in location.

Positive concordance: Mitral annulus, negative concordance: LV apex.

Slurred wave, wider QRS, Q wave of lateral leads for LV-VT, R wave in RV-VT: Epicardial in position.

2. Entrainment technique

3. Electrogram Characteristics

Bipolar Eg: < 3 deflection, > 2 mV, < 70 msec, amplitude/duration<0.05

AbnormalAbnormal NormalNormal

4. Substrate Mapping: Strategy

Zipes DP et al. Catheter Ablation of Arrhythmias, 2nd edition, 2002

Ventricular Tachycardia RV ICD Lead Pacing Case 1

LVZ

Ablation site

LVZ

LVZ

Bi-Ventricular Voltage Map


ICD Lead

LV apex

Septum

RVOT

Ischemic LV VT---Case 1The important to identify chamber to ablate



Ischemic LV VT---Case 2The important to identify the LVZ and critical

Channels and exit site

Tsai and Chen, Circ J, 2011

Conclusions Outflow tract VT Outflow tract VT is the commonest form of idiopathic is the commonest form of idiopathic

VT. VT. ECG morphology ECG morphology is important for localization of focais important for localization of foca

l VT and exit site of substrate VT.l VT and exit site of substrate VT. Pacing mapping Pacing mapping may not sensitive to locate the sites may not sensitive to locate the sites

of foci in certain patients with focal VT, scar-VT, epicof foci in certain patients with focal VT, scar-VT, epicardial VT, and fascicular VT.ardial VT, and fascicular VT.

In the stable VT of abnormal ventricular substrateIn the stable VT of abnormal ventricular substrate: a: activation maps and entrainment technique are imporctivation maps and entrainment technique are important to decide the targets.tant to decide the targets.

In unstable VT, VF, and non-inducible VTIn unstable VT, VF, and non-inducible VT, substrate , substrate mapping during SR could be identify to determine thmapping during SR could be identify to determine the critical substrate. e critical substrate.

Brugada syndrome---Case 3Identification of LVZ and prolonged potentials

Bipolar Eg > 1.5mVBipolar Eg > 1.5mV

Unipolar Eg > 5mVUnipolar Eg > 5mV

AbnormalAbnormal

RV endocardiumRV endocardium

RV endocardiumRV endocardium

Brugada syndrome---Case 3Late potential maps

RV endocardiumRV endocardium RV epiardiumRV epiardium

Post ablation> No inducible VT/VFPost ablation> No inducible VT/VF

Before epicardial puncture After epicardial puncture

Changes in ECG during the procedureChanges in ECG during the procedure

Health & Medicine

Catheter ablation of ventricular tachycardia