- Catheter ablation is an effective treatment for ventricular tachycardia (VT) in both structurally normal hearts and those with structural heart disease. - For normal hearts, activation mapping and pace mapping are used to identify the origin of VT, with typical sites including the right ventricular outflow tract. Success rates are high with few complications. - In structural heart disease, substrate mapping is used to identify scar tissue which hosts reentrant VT circuits. Entrainment mapping during VT can confirm circuits. Ablation targets abnormal potentials in scar or the scar border zone. Integration of cardiac imaging helps define substrate. Long-term outcomes after ablation are improved compared to antiarrhythmic drugs alone.

1. CATHETER ABLATION FOR
VENTRICULAR TACHYCARDIA

2. Introduction
• Ventricular arrhythmias= premature ventricular complexes (PVCs) to
monomorphic ventricular tachycardia (VT) and polymorphic VT/ventricular
fibrillation (VF).
• These arrhythmias can occur in the presence and absence of structural
heart diseases (SHD).
• In the more than three decades since first described, VT catheter ablation as
progressed as a ‘tale of two cities’.
• In patients with a structurally normal heart,
 Idiopathic
 Inherited ion channel abnormality
• In patients with structural heart diseases (SHD)
 IHD related
 Non Ischaemic Cardiomyopathy (NICM)

3. 1972 1978 1988 2004
First EP study for
VT
Catheter
ablation- DC
SHOCK
catheter
ablation-
RFA
surgical VT
ablation
THE TIMELINE
1998 20031982
Non
fluoroscopic
navigation
systems (EAM)
1994
Use of ICE for
RFA
MDCT-guided
catheter
manipulation
MRI integration
during EAM

4. Induced By
Triggered activity
EADs Torsade de pointes Bradycardia
DADs Idiopathic outflow tract VT rapid pacing, programmed
stimulation,
or isoproterenol infusionPurkenjie system related
PMVT/ VF ( Post MI)
Abnormal
automaticity
Fascicular VT
( propranolol sensitive)
isoproterenol infusion
Re-entrant Fascicular VT
(Verapamil sensitive)
Structural heart disease ( scar-
related)
Bundle Branch reentrant VT
(DCMP)
programmed stimulation
The mechanisms underlying
monomorphic VT or PVCs
Antzelevitch C, et al., Card Electrophysiol Clin
2011;3:23–45.

5. Categories Pros Cons
AADs Conventional;
As an initial try
Mostly inefficacious
Can actually increase
mortality
Multiple toxicities
ICD A significant mortality benefit Not curative
High cost
Multiple shocks
detrimental
Surgical Ablation
Optimal removal of the
arrhythmogenic substrate
Significant mortality (3-
14%)
Catheter Ablation Often Curative in certain VTs Accessibility issue
Challenging task
Treatment of Ventricular
Arrhythmias

6. Catheter Ablation of VT in
Structurally Normal Hearts
1. General Consideration
2. Indication
3. Approach
a. Role of Surface ECG
b. Mapping
4. Ablation in Specific Phenotypes
5. Outcomes and safety

7. General Consideration
• Patients with idiopathic VT have a low risk of sudden death, and placement
of an ICD is generally not warranted.
• Hence a curative strategy is better favourable with catheter ablation.

8. J A C C V O L . 7 0 , N O . 2 3 , 2 0 1 7 Dukkipati et al. D E C E M BE R 1 2 , 2 0 1 7 : 2 9 0 9 – 2 3

10. A stepwise approach: Localisation of VT
by Surface ECG
• A. Surface ECG- For Entry, Exit
European Heart Journal (2016) 37, 594–609

11. If 12-lead ECG does not provide clear criteria to guide
ablation
In the setting of the common LBBB-like inferior axis
idiopathic VT, mapping should start from the RVOT.
Subsequent mapping of the distal coronary sinus can add
useful information and occasionally enable the ablation of
an epicardial origin
If activation and pace mapping suggest the origin outside
these RVOT and distal coronary sinus, mapping of the
LVOT and aortic sinus of Valsalva via retrograde arterial
access is the typical next step
If all previously described approaches to mapping and
ablation fail, epicardial mapping via percutaneous
pericardial access should be considered
J Am Coll Cardiol 2005;45:418–423.

13. Activation mapping
• ‘Activation mapping’ is the method of choice for mapping idiopathic VT
and PVCs.
• Activation mapping involves the identification of the earliest site of
electrical activation in a cardiac chamber in comparison to an arbitrary
reference electrogram during VT.
• The ability to induce the clinical arrhythmia in the EP laboratory is a very
important factor for the success of ablation.
• Rapid burst pacing, isoproterenol infusion, Epinephrine, phenylephrine,
aminophylline, calcium infusion, or atropine may facilitate arrhythmia
induction.
• Earliest local activation on the bipolar electrogram from the responsible
focus typically precedes the QRS onset by 15–45 ms during VT or PVCs
with a characteristic QS complex in the unipolar signal.
J Cardiovasc Electrophysiol 2005;16:823–829.

14. J A C C V O L . 7 0 , N O . 2 3 , 2 0 1 7 Dukkipati et al. D E C E M BE R 1 2 , 2 0 1 7 : 2 9 0 9 – 2 3

16. Pace mapping
• This method involves pacing from various sites and comparing the paced
QRS morphology with the target PVC to assess for similarity.
• Pace maps with identical or near-identical matches of VT morphology in
all 12-lead ECG are indicative of the site of origin of the VT/PVCs.
• This approach to mapping is used to confirm the results of activation
mapping.
• It can be of value when VT is difficult to induce and/or clinical PVCs
are infrequent, which severely limit the ability to perform activation
mapping.
• The specificity of pace mapping in isolation appears to be lower than that
of activation mapping. When possible, it is optimal to rely on both pace
mapping and activation mapping. Activation mapping is preferable, as pace
mapping has a lower spatial resolution.
J Cardiovasc Electrophysiol 2005;16:823–829.

18. Fascicular VT
• For verapamil-sensitive reentrant VT,
 Inducible VT- Entrainment mapping- the anterograde Purkinje potentials or
diastolic potentials during VT as a target.
 Non inducible VT- Substrate ablation- a linear lesion perpendicular to the long
axis of the ventricle approximately midway from the base to the apex in the
region of the mid to mid-inferior septum
• For focal Purkinje VT- Activation mapping- the ablation target is the earliest
presystolic Purkinje potential during VT.
• Fascicular VT vs Interfascicular VT vs BBR VT - Needs to be
distinguished

19. Nogami Aet al , J Am Coll Cardiol 2000;36:811–23.

20. PVC-triggered Polymorphic VT And
VF
• These triggers were mapped to the right or left Purkinje system in 83% and
the ventricular myocardium in the right ventricular outflow tract in 17%.
• Seen in SHD, Post MI(focal PVC triggers from surviving Purkinje fibers
situated along the scar border), Inherent arrhythmias(long QT syndrome,
Brugada syndrome, catecholaminergic polymorphic VT, and early
repolarization)
Haissaguerre M et al, Circulation 2002;106:962–7.

21. Brugada syndrome
• The PVC triggers are from the RVOT.
• In addition to PVC triggers of VF, recent studies have demonstrated that
Brugada syndrome represents a special situation where the VF substrate itself
can be mapped.
• RVOT epicardium characterized by abnormal, low-voltage, fractionated
electrograms is critical to the type 1 Brugada ECG phenotype and pathogenesis
of Brugada-related VF.
• After pericardial access, targeting the substrate (low voltage, fractionated
electrograms) along the RVOT epicardial surface can normalize the ECG and
prevent VF.
Nademanee et al., 2011

23. Outcomes and safety

24. T. Tanawuttiwat et al., European Heart Journal (2016) 37, 594–609

25. PVC related VAs- Outcomes
PVC INDUCED CARDIOMYOPATHY
successful ablation (>80%
reduction) of frequent PVCs – LVEF 67%
had improvements >10%, 18% had
improvements of <10%
PVC-TRIGGERED POLYMORPHIC VT AND
VF
82% rate of freedom from recurrent VF
during a median follow-up of
5 years;
Successful repeat ablation
Marrouche NF, J Am Coll Cardiol 2004;43:1715–20

26. Complications
• Complications of catheter ablation of idiopathic VT ablation are rare, with
a reported complication rate of 3–5%.
• Access site vascular complications (pseudoaneurysm, hematoma, or AV
fistula) are most frequent. (2%)
• Less common complications include cardiac tamponade/
haemopericardium (0.8%), thromboembolic events, AV block (0.1%), and
coronary artery injury.
• Major complication rates are lowest for ablation in the RVOT.
Hsia HH etal, Circulation 2003;108:704–710

27. Failed ablation
Common causes of failed
ablation
 Imprecise mapping
 Inability to reach the site of
origin, especially intramural and
epicardial locations,
 Limited power delivery
 Inadequate catheter stability
 Paucity of PVCs during the
procedure.
Methods to overcome these
limitations
 Multi-electrode array sampling
multiple sites simultaneously
 Using ICE to navigate the
catheter in pap pvcs/vt.
 Adjusting the level of sedation
along with isoproterenol or
calcium infusion to increase intra-
procedural pvcs
 Epicardial ablation
 Using contact force ablation
catheters.
Inability to induce PVCs or VT is the most common cause of
unsuccessful Ablation
Bougun F et al, Heart Rhythm 2008;5:
339–44.

28. ICE
Circulation. 2018;137:2278–2294

29. Catheter ablation of VT in
Structural heart diseases
1. General Consideration
2. Indication
3. Approach
 The characterization of target VTs,
 Delineation of the arrhythmic substrate,
 Radiofrequency ablation of the arrhythmic tissue.
4. Ablation in Specific Phenotypes
5. Outcomes and safety
6. Future Directions
7. Trials and Guidelines

30. General Consideration
• VT that occurs in patients with structural heart disease carries an elevated
risk for sudden cardiac death (SCD).
• ICDs are the mainstay of therapy. In these individuals, catheter ablation
may be used as adjunctive therapy to treat or prevent repetitive ICD
therapies when antiarrhythmic drugs are ineffective or not desired.
• The main goal of VT mapping in patients with SHD is identification of
the site of origin for triggered activity or the critical isthmus for reentrant
VT.

32. Step1: Characterization of target
VTs
• Target VTs include all clinically occurring VTs and those induced with programmed
stimulation.
• Typically, programmed ventricular stimulation is performed at 2 drive cycle lengths with
up to 3 extra stimuli delivered at progressively shorter coupling intervals at 2 ventricular
locations.
• Programmed ventricular stimulation is important
 To confirm the diagnosis,
 Assess the possibility of bundle branch reentry, which requires a different approach,
 Provide a QRS morphology to compare with pace-maps
 To validate the use of programmed stimulation as an endpoint for the ablation procedure.
• When VT is induced, pace termination or electrical cardio version is performed, and
programmed stimulation is continued until the same VT is repeatedly induced or multiple
electrical cardioversions are required.
• For each VT, the 12-lead ECG morphology, the rate (or cycle length), bundle branch block
morphology, axis, precordial transition, and the hemodynamic effect are all recorded. This
helps to localize the VT exit site and also to determine the ablation strategy.
Marchlinski FE et al, Circulation 2000;101:1288–96

33. Step 2: Delineation of the arrhythmic
substrate (Substrate mapping)
• The myocardial scar is identified using a 3- dimensional (3D)
electroanatomic mapping system that allows:
1) Spatial localization of a mapping catheter;
2) Generation of a 3D anatomic representation of the ventricle that is
color-coded based on electrogram voltage amplitude recorded from the
mapping catheter to differentiate normal myocardium from scar or border
zone tissue; and
3) Cataloging of myocardial channels and potential VT circuit isthmus sites
identified on the basis of abnormal electrogram characteristics. (Into
Normal, Border Zone, Scar tissue)
Marchlinski FE et al, Circulation 2000;101:1288–96

36. Endocardial Bipolar voltage Endocardial
unipolar voltage
Normal
myocardium
>1.5
mV
LV ≥8.27 mV
RV ≥5.5 mV
Border zone
tissue
0.5 to
1.5 mV
Fractionated
electrograms
No
isoelectric
interval LAVA
(Local
abnormal
ventricular
activity )
late (or isolated)
potentials
isoelectric
interval of
>20 ms
Dense scar <0.5
mV
The VT ablation endpoint as LAVA elimination, additional to non-inducibility, has
showed to be associated with a reduction in recurrent VT or death during long-
term follow-up and become the better predictor of success in substrate ablation.

37. USUAL LOCATION OF THE
SUBSTRATES
• POST MI SCAR- Subendocardium
• DCMP- Midmyocardial or epicardial and most often occurs in the basal
anteroseptal and inferolateral LV regions.
• ARVC/D- Begins in a subepicardial location and progresses toward the
endocardial surface.
• HOCM- Myocardial scar+- LV Aneurysm
.
• SARCOIDOSIS- sub epicardial and transmural LV wall, Basal septal
• CHAGAS- Inferolateral and Apical LV segments- Both Subendocardial and
subepicardial
Miller MA et al, Circ Arrhythm Electrophysiol
2013;6:151–9.

39. SUBSTRATE MAPPING
IMAGE GUIDED
• Voltage mapping may be challenging to identify septal or mid-myocardial substrates.
• Regions of late gadolinium enhancement on cardiac MRI have been successfully
integrated within electroanatomic mapping systems to define the presence of,
subendocardial, transmural, mid-myocardial or epicardial scar, and to identify septal
substrates for ablation in both NICM and ischaemic cardiomyopathy (ICM).
• A major limitation of MRI as a tool for VT ablation is the presence of an ICD in many
patients undergoing this procedure. Fortunately, techniques have been developed to
safely image patients with ICD systems, and a wideband late gadolinium enhancement
technique has been developed to eliminate hyper-intense artefacts from the ICD
generator.
• The ancillary study of intervention mechanisms for ventricular tachycardia study, an
ancillary STAR-VT study, will examine the CT substrate for VT and the impact of
ablation upon that substrate.
• An imaging study combined with 252-lead ECG has been used to develop non-invasive
mapping, guiding catheter ablation in both idiopathic VT and defining substrate in
ischaemic VT.
European Heart Journal (2016) 37, 594–609

40. Sebastiaan RD etal,Arrhythmia & Electrophysiology Review 2013

41. STEP 3: Ablation strategies of the
arrhythmic tissue.
• Entrainment mapping,
• Activation mapping,
• Pace mapping, and
• Substrate modification for VT.

42. Entrainment mapping
• This is the most reliable method for determining the relevance of a
channel of activation in a reentrant circuit.
• Entrainment is the continuous resetting of a reentry circuit.
• The demonstration of entrainment can potentially be assessed during
 The initiation of VT,
 During pacing in stable VT that continues after pacing(By resetting),
 With VT termination
• The demonstration of entrainment proves that the tachycardia is
reentrant in nature.
William G. Stevenson etal, Card Electrophysiol Clin 9 (2017) 55–69

43. REENTRY
Circuit
William G. Stevenson etal, Card Electrophysiol Clin 9 (2017) 55–69

44. Resets
the Cct
Temporal relatiion
Spatial Relation
VT Termination
VT Initiation

45. ENTRAINMENT
Tachycardia Wavefront
Orthodromic Wavefront
Antidromic Wavefront Fusion
Resetting

46. Concealed Fusion
Constant Fusion

47. Circulation 1993;88(4 Pt 1):1647–1670.

48. Entrainment mapping- PROS AND
CONS
• In the setting of stable sustained VT, targeted isthmus ablation at sites with
the three entrainment criteria (PPI–TCL ≤ 30 ms, stimulus to QRS
interval <70% of TCL, and concealed entrainment) has the highest success
rate with positive predictive value of 100% and negative predictive
value of 96% for prediction of VT termination with RF application at
that site.
• However, almost 80% of induced VT episodes in SHD are either non-
sustained and if sustained are haemodynamically intolerable, thus
precluding proper entrainment mapping.
• As a result, pace and substrate-mapping strategies are the main stay
approach for VT ablation in most patients with SHD.
William G. Stevenson etal, Card Electrophysiol Clin 9 (2017) 55–69

49. Activation mapping
• The focus of activation mapping during reentrant is to identify sites with
bipolar electrogram evidence of continuous diastolic activity, isolated
diastolic potentials, or both.
• Unlike idiopathic VT, there is no earliest or latest point of activation in
reentry.
• It is important to note that mid diastolic sites can be part of abnormal slow
conduction unrelated to the VT circuit.
• Therefore, activation mapping in isolation is not a reliable method for
reentrant VT in SHD but can be a useful adjunct in conjunction with other
mapping modalities.
• It can be promising in Triggered activity related VT in SHD.
Brunckhorst CB et al, J Am Coll Cardiol
2003;41:802–9.

51. Pace mapping
• Pace mapping,’ which can be used for identification of the arrhythmia
source in triggered VT and for identification of the VT exit site in reentry,
is another methodology that enables mapping during sinus rhythm.
• An identical paced 12-lead vs. VT 12-lead ECG morphology match
suggests proximity to the exit or isthmus of the VT reentry circuit, or the
source of triggered foci.
• During pace mapping of reentrant VT, a long stimulus-to-QRS interval
(≥80 ms) during pacing indicates regions of slow conduction-Potential VT
Isthmus.
• Pacing threshold ≥10 mA has been used to define unexcitable scar,
provided electrode-tissue contact is adequate.
Brunckhorst CB et al, J Am Coll Cardiol
2003;41:802–9.

52. William G. Stevenson etal, Card Electrophysiol Clin 9 (2017) 55–69

53. Substrate ablation
• Substrate ablation is developed from the concept of surgical ablation by
removal of arrhythmogenic tissue.
• Used in the setting of unmappable VT.
• VISTA trial
 Ablation of clinical VT vs. additional of substrate ablation on the long-
term success rate in ICM patients presenting with stable VT.
 Result- 12-month freedom of recurrent VT in substrate ablation group was
higher than isthmus ablation group (84.5 vs. 51.7%, P , 0.001) without
differences in mortality rate and complication rate.

54. Substrate Ablation strategies

56. External haemodynamic support
devices in VT Ablation
• Devices-
 Intra-aortic balloon Pump
 Percutaneous left ventricular assist devices,
 Extracorporeal membrane oxygenation (ECMO)- maximal hemodynamic
support (>4.5 l/min).
• There was no improved short-term success or greater long-term freedom
fromVT when haemodynamic support is used for delineation of the critical
isthmus and targeting of VTs.
• Therefore, the use of these devices has been primarily restricted to patients
 who failed substrate-based ablation or
 have recurrence of rapid VTs
 with very poor LV function.

57. The end point of Ablation
• The best end point for the ablation has not been well defined.
• However, complete VT non-inducibility was found to be associated with
reduction of the likelihood for all-cause mortality in patients with NICM
and be associated with longer longevity and lower VT/VF recurrence in
post-infarction VT.
• Therefore, a noninducibility of any VT is a reasonable end point for VT
ablation.

58. Carrbucicchio Heart RHYTHM,2013
Fernandez Armenta J, Heart Rhythm 2016
DiBase, L, JACC, 2915

59. Early VS Deferred VT ablation
• Early VT ablation, defined as ablation within 30 days after the first
documented VT, has been associated with a lower VT recurrence rate, as
compared with VT ablation performed later.
• Advantages of Preventive catheter ablation (Before ICD Therapy)-
 Significantly reduces ICD shocks.
 Arrhythmic storm may be reduced
 Might contribute to improved prognosis
 Not associated with significant procedural complications. and increased
mortality

60. Outcomes and safety

61. LANDMARK TRIALS
SMASH-VT( 2007)
ICD in ALL
AAD Naive
VTACH (2010)
Already on AADS
Stable VT
VANISH(2016) Rec VT Despite
AADs
SMS (2017) Unstable VT
INTERVENE (2020) No ICD Already on AADS-Upon meta-analysis, patients who were randomized to Catheter ablation group
had decreased odds of appropriate ICD therapies, appropriate ICD shocks , VT
storm and cardiac hospitalizations .
-There was no evidence of a significant difference in the odds of recurrent VT/VF
or All-cause mortality.

62. INTERVENE TRIAL
Arm/Group Title
(Post MI> 1 month duration +- VT/VF, No
ICD)
Amiodarone Only Amiodarone +
Catheter Ablation
Overall Number of Baseline Participants 27 26
Age, Continuous Mean (Standard
Deviation)
Unit of measure: Years
54.9 (10.7) 53.8 (10.4)
Primary Outcome(Number of participants
who had no occurrences of all-cause
mortality, sustained ventricular tachycardia
(VT) and cardiac arrest at 24 months)
16 (59.3%) 21 (80.8%)
Secondary Outcome(Number of subjects
that die within 30 days or die by 24
months.)
2
7.4%
2
7.7%
Total number of ventricular arrhythmic
events, at 24 months
15 5

63. Complications
• Major complications is access related (most frequent ), cardiac tamponade
and thromboembolic events.
• Overall, complications rate of VT ablation in SHD is about 8%.
• The overall long-term mortality of VT patients with SHD is from 4 to 22%.
• Acute hemodynamic decompensation, defined as persistent hypotension
despite vasopressors requiring mechanical support or discontinuation of
the procedure, is reported to occur in 11% of patients and portends
increased mortality.
• The independent predictors of complications include age, renal
insufficiency, depressed LVEF, and operator experiences.
• Ablation reduces VT recurrence without significant impact upon mortality
when an ICD is present.
• 1-year freedom from VT recurrence is associated with improved transplant-
free survival, independent of heart failure severity.
• Worsening heart failure resulting from catheter ablation can be a concern.
But not so when ablation is performed by an experienced operator.
Tung R, et al; Heart Rhythm 2015;12:1997–2007.
Frankel DS et al, J Am Coll Cardiol 2017;69: 2105–15.

65. Failed ablation
Common causes of failed
ablation
 Imprecise mapping
 Inability to reach the site of origin,
especially intramural and epicardial
locations, the proximity of lesions
to His/coronary artery/ phrenic
nerve.
 Limited power delivery
 Inadequate catheter stability
 Paucity of PVCs during the
procedure.
Methods to overcome these
limitations
 Epicardial ablation
 Ancillary Techniques
 Surgical ablation/hybrid
procedure
The acute success of catheter ablation in VT with SHD is limited as Post-
ablation attempts to reinduce VT are often not performed due to
haemodynamic instability.

66. Epicardial ablation
• Indication-
 A failed prior ablation,
 VT unrelated to coronary artery disease (i.e., DCM,
ARVC/D, HCM, and Chagas cardiomyopathy, )
 A CMR suggesting midmyocardial or epicardial scar, or
 an ECG suggestive of an epicardial exit
• Epicardial Access- Usual subxyphoid (percutaneous/ Surgical)

68. Advance Technology
• Research is ongoing to develop ablation tools that achieve more effective
and deeper ablation lesions to address intra-myocardial Catheter ablation in
VT substrates.
• Ancillary Techniques-
 Trans coronary ethanol ablation
 Bipolar RF ablation,
 Irrigated needle ablation,
 Stereotactic radioablation
 Autonomic modulation/ left or bilateral cardiac sympathetic denervation
(CSD)
 High-frequency focused ultrasound
 Electroporation

72. COR LOE Recommendations for Outflow Tract VA
I B-NR
1. In patients with symptomatic outflow tract VA in an
otherwise normal heart for whom antiarrhythmic
medications are ineffective, not tolerated, or not the
patient’s preference, catheter ablation is useful
COR LOE Recommendation for Papillary Muscle VA (PVCs and VT)
I B-NR
1. In patients with symptomatic VA arising from the papillary
muscles for whom antiarrhythmic medications are ineffective,
not tolerated, or not the patient’s preference, catheter
ablation is useful.
COR LOE
Recommendations for Interfascicular Reentrant VT (Belhassen
Tachycardia)
I B-NR
1. In patients with verapamil-sensitive, idiopathic LVT related to
interfascicular reentry for whom antiarrhythmic medications
are ineffective, not tolerated, or not the patient’s
preference, catheter ablation is useful.
2017 AHA/ACC/HRS Guideline for Management of Patients With Ventricular
Arrhythmias and the Prevention of Sudden Cardiac Death

73. COR LOE Recommendations for Idiopathic Polymorphic VT/VF
I B-NR
For patients with recurrent episodes of idiopathic VF initiated by
PVCs with a consistent QRS morphology, catheter ablation is
useful.
COR LOE Recommendations for PVC-Induced Cardiomyopathy
I B-NR
For patients who require arrhythmia suppression for symptoms or
declining ventricular function suspected to be due to frequent
PVCs (generally >15% of beats and predominately of 1
morphology) and for whom antiarrhythmic medications are
ineffective, not tolerated, or not the patient’s preference,
catheter ablation is useful.
COR LOE Recommendations for Brugada Syndrome
I B-NR
For patients with recurrent episodes of VT, VT storm, aborted
SCD, despite ICD or with inegibility for ICD/ not patient’s
preference for ICD catheter ablation is useful.
2017 AHA/ACC/HRS Guideline for Management of Patients With
Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death

74. Treatment of Recurrent VA in Patients With Ischemic Heart
Disease or NICM
Polymorphic
VT/VF
Sustained
monomorphic VT
Identifiable
PVC triggers
Consider
reversible
causes
Amiodarone
(Class I)
Catheter
ablation
(Class I)
Autonomic
modulation
(Class IIb)
Yes No
Amiodarone or
sotalol
(Class I)
Catheter
ablation
(Class I)
ICD with VT/VF
recurrent arrhythmia*
Revascularize
(Class I)
Treat for QT prolongation,
discontinue offending
medication,
correct electrolytes
(Class I)
Drug, electrolyte induced Ischemia
Catheter ablation
as first-line therapy
(Class IIb)
Yes
Catheter
ablation
(Class IIa)
NICMIHD with
frequent VT or
VT storm
No
Catheter
ablation
(Class IIa)
Beta blockers
or lidocaine
(Class IIa)
Arrhythmia
not controlled
Arrhythmia
not controlled
No reversible causes
2017 AHA/ACC/HRS Guideline
for Management of Patients
With Ventricular Arrhythmias
and the Prevention of Sudden
Cardiac Death

75. 2019 Expert Consensus on Ablation of
Ventricular Arrhythmias
• Revascularization alone is unlikely to reduce the recurrence of Scar related monomorphic VT in IHD.
• CMR and programmed ventricular stimulation can be useful for risk stratification for sudden cardiac death
in patients with frequent premature ventricular contractions (PVCs). Periodic measurement of left
ventricular ejection fraction (LVEF) and LV end-diastolic dimensions, along with quantification of PVC
burden, may be useful for patients with a high PVC burden (approximately 10% or higher) to identify
deteriorating LV function before symptoms of heart failure appear.
• For patients who are clinical nonresponders to cardiac resynchronization therapy, with limited
biventricular pacing due to frequent PVCs, successful PVC ablation is associated with improvement in
heart failure class and a modest improvement in LVEF.
• The PAAINESD risk score is helpful to identify patients undergoing scar-related VT ablation who are at
increased periprocedural risk.
• Advanced cardiac imaging, such as computed tomography (CT), cardiac magnetic resonance imaging
(CMR), and fluorodeoxyglucose positron emission tomography are useful for the evaluation in patients
with Vas.
• For intraprocedural imaging during ablation of VAs, fluoroscopy (including coronary angiography) and
especially intracardiac echocardiography are useful.
• In addition to the traditional unipolar radiofrequency catheter ablation, innovation and new modalities of
tissue destruction may help to improve outcomes of VA ablation. Contact force sensing, hypotonic
external irrigation, simultaneous unipolar or simultaneous bipolar radiofrequency delivery, needle
ablation, cryoablation, transvascular ethanol ablation, and stereotactic radiofrequency offer specific
advantages in appropriate clinical scenarios and may improve outcomes of the ablation procedures.
2019 HRS/EHRA/APHRS/LAHRS Expert Consensus Statement on Catheter Ablation of Ventricular Arrhythmias. Heart Rhythm 2019;May 10

76. CONCLUSIONS
• In Structurally Normal Heart-
 The techniques and outcomes of catheter ablation of idiopathic VT has rapidly
matured, with compelling demonstration of a safe, effective, and curative
procedure.
 In the absence of structural heart disease, catheter ablation can be performed
for symptomatic and frequent PVCs or idiopathic LV VT either as first-line
treatment or for arrhythmias refractory to medical therapy.
 Succesful Catheter ablation can obviate the need of ICD in idiopathic VT .
• In SHD-
 VT catheter ablation in patients with SHD has followed a very different
trajectory, and remains in its infancy.
 It is best used as an adjunct to ICDs, and as an alternative or adjunct to
antiarrhythmic drugs.
 Earlier referral for VT ablation is strongly associated with improved outcomes
when compared to later referral.
 For High risk patients, Catheter ablation with Percutaneous haemodynamic
support helps to abate periprocedural hamodynamic decompensation.

77. TAKE HOME MESSAGE
• In Symptomatic VAs in Structurally Normal Heart,
Catheter ablation should be a straightforward
management plan.
• In SHD with repeated appropriate ICD therapies,
Catheter ablation seems to be noteworthy.

78. THANKS