Vikas Kuriachan MD FRCPC FCCS FHRS FACCCardiology/ Cardiac Electrophysiology

Clinical Associate Professor of Medicine

Director of Cardiac Implantable Electronic Device Services (Calgary)

University of Calgary

Libin Cardiovascular Institute of Alberta

March 12, 2019

Management of Ventricular Tachycardia

In Structural Heart Disease:

Reason for Hope

DISCLOSURES• Relationships with commercial interests:

• Advisory Board:

• Medtronic

• Bayer

• Servier

• Bristol-Myers Squibb/Pfizer

• Research Support

• Medtronic

• St Jude Medical

• Speakers Bureau/Honoraria:

• Medtronic

• Johnson & Johnson / Biosense Webster

• Bayer

• Boston Scientific

• Servier

• Patents /Technology

• Apparatus for stabilizing /fixating medical device leads (provisional patent application)

OBJECTIVES

• Identifying patients with structural heart disease who are at risk for life

threatening ventricular arrhythmias

• Understanding the role of ICD, anti-arrhythmics, and ablation in the

management of ventricular tachycardia and structural heart disease

Monomorphic Ventricular Tachycardia (VT)

NOT DISCUSSING

•Polymorphic VT

•Torsade de pointes

•VF

ALSO NOT DISCUSSING…IDIOPATHIC VENTRICULAR TACHYCARDIA

• VT without structural heart disease (focal origin)

• Normal ventricles

• Same mechanism for PVCs (with or without tachycardia)

• Usually have very good prognosis

• Treatment usually for symptoms (or if cardiomyopathy)

• Beta or calcium channel blockers

• Antiarrhthmics

• Ablation

• Since almost no risk for sudden cardiac death

Gerstenfeld et al. Curr Prob Card 2013;38:131-158

WHAT IS VT WITH STRUCTURAL HEART DISEASE?

• Common causes

• Ischemic

• Non-ischemic / Dilated

• Myocarditis

• Hypertrophic Cardiomyopathy (HCM)

• Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)

• Sarcoid

• Usually results in scar in the ventricles

• Substrate for re-entrant arrhythmias

• May result in sudden cardiac death

• Usually have ICD and optimal cardiac medications

Kuriachan et al Curr Prob Card 2015:40(40):133-200

Exit

Slow Conduction (isthmus)

REENTRY CIRCUIT

• Reentry through an anatomic barriers

• Scar

• Valve annulus

• Zone of slow conduction

Courtesy of Drs I Kosmidou / W Stevenson

Mitral

Valve

Aortic

Valve

• Areas of scar are often large

• Reentry circuits can be large

• Multiple potential reentry circuits

exist and different VT morphologies

can occur

• Critical part of circuit is the isthmus

Courtesy of Dr. I Kosmidou/W Stevenson

VENTRICULAR ARRHYTHMIA LEADING TO LOSS OF ELECTRICAL ACTIVITY AND SUDDEN CARDIAC DEATH

www.uptodate.com

1 American Heart Association. Heart Disease and Stroke Statistics –2005 Update.2 Jemel A. CA Cancer J Clin. 2003;53:5-26.

3 U.S. HIV & AIDS Statistic Summary. Avert.org

SUDDEN CARDIAC DEATHS IN THE US

Breast

Cancer2

335,000

SCD3

18,000

40,000

152,200

163,000

AIDS3

Lung

Cancer2

Stroke1

SCD claims

many lives

each year

compared to

other causes

CASE - MR. M

• Mr M. 65 male with MI then underwent CABG. EF 20%. NYHA III

• Also:

• Permanent atrial fibrillation

• Hypertension

• Diabetes II

• Dyslipidemia

• Mild –mod renal dysfunction (GFR 50)

• He has scar in his ventricles and is at risk of sudden death

Zeitler et al JCE 2017;28(11):1345-1351

• Patients with prior MI or LV dysfunction

• Treat reversible causes (revascularize)

• Ensure appropriate electrolyte levels

• Magnesium, Potassium

• Optimal medical therapy for underlying heart problem

• Beta blockers

• Metoprolol, Bisoprolol, or Carvedilol

• Other cardiac medications that seem to be beneficial in reducing

sudden death

• Usually studied in patients with post-MI, coronary artery disease,

and or heart failure

• Statins

• ACE-Inhibitors

• Angiotensin receptor blockers

• Aldosterone blockers (spironolactone or eplerenone)

• Sacubitril / Valsartan (Entresto)

Mitchell LB Cardio Clin 26 (2008):405-418

McMurray et al NEJM 2014:371:993-1004

MR M.

• Optimized on medications.

• NYHA II

• EF improved to 28% on assessment six months later.

• Hence he received a primary prevention implantable cardioverter

defibrillator (ICD)

Risk of ventricular arrhythmias 5 – 10% per year

Zeitler et al JCE 2017:28(11):1345-1351

ICD will reduce mortality and prevent

arrhythmias?

• A) True

• B) False

ROLE OF ICD – REACTIVENOT PREVENTATIVE

• Implantable Cardioverter Defibrillator

• Risks / benefits of procedure versus condition

• Risk of ICD Implant

• Death is < 0.1%

• Other complications range 1 – 10%

• Infection, pneumothorax, device problems, etc..

• Over a few years

• ICD usually implanted in those deemed to be high risk

for SCD

• Not always very clear

• Need extensive discussion with patient

WHO SHOULD RECEIVE AN ICD

• Persistent Severe LV dysfunction after optimal treatment (EF < 35%)

• Primary prevention

• Most common reason today

• Prior cardiac arrest or significant, life-threatening ventricular arrhythmias

(not reversible)

• Secondary prevention

• VF in context of acute MI would be considered reversible and does not usually require

ICD

• Other risks factors/conditions

• HCM, Long QT, ARVC……

• Not just diagnosis but depends on risk of SCD

Kuriachan V et al Curr Treat Options Cardiovasc Med 2009 Feb;11(1):10-21

Life Expectancy > 1 Year

CLINICAL TRIALS USING ICD TO DECREASE MORTALITY IN PATIENTS WITH LV DYSFUNCTION

Estes Circ 2011;124:651-656

TRANSVENOUS ICD

kronstantinople.blogspot.com

Boston Scientific

EXTRAVASCULAR OR SUBSTERNAL(BEING DEVELOPED)

Startribune.com

MR. M TWO YEARS LATER…………

Presents with symptomatic VT

episodes and ICD shocks

Baseline ECG

STABILIZED WITH IV AMIODARONEWHAT CAN WE DO NOW?

• Treat any CHF and ischemia

• Further optimize beta-blocker

• Consider an antiarrhythmic

Courtesy of Dr. I Kosmidou/W Stevenson

Antiarrhythmics will change the

properties of the circuit and

minimize triggers (PVCs) to

prevent VT

ANTI-ARRHYTHMIC MEDICATIONS VAUGHAN WILLIAMS CLASSIFICATION

• Class I – Sodium channel blockers

• Flecainide, Propafenone, Lidocaine

• Class II – Beta blockers

• Class III – Potassium channel blockers

• Sotalol, Amiodarone

• Class IV – Calcium channel blockers

• Others (Digoxin)

Copyright unknown

• Many antiarrhythmics may worsen outcomes in patients with prior MI

and LV dysfunction:

• Class I agents (Flecainide, propafenone, etc)

• Class IV agents (Diltiazem)

• No benefit for digoxin for ventricular arrhythmia prevention

• Hence the main anti-arrhythmic options in patients with VT and

structural heart disease:

• Beta-blockers

• Add Sotalol (except with renal dysfunction or severe CHF)

• Or Add Amiodarone

TREATMENT OPTIONS

HR 0.27P<0.001

P=0.055

P=0.02

Optic Connolly et al. JAMA 2006

• Sotalol works, just not as well as amiodarone

• But much better side-effect profile

ICD shock reduction

BACK TO MR. M

• Patient sent home on amiodarone 200 mg daily (added)

• After loading 20 grams

• Returns six months later with multiple ICD shocks for VT again

• What now?

VANISH STUDY

VENTRICULAR TACHYCARDIA ABLATION VERSUS

ANTIARRHYTHMICS IN ISCHEMIC HEART DISEASE

• Randomized patient with prior MI and ICD who have

failed one antiarrhythmic to:

• More aggressive antiarrhythmic therapy or

ablation

Sapp et al N Engl J Med 2016; 375:111-121

PRIMARY OUTCOME: DEATH, VT STORM, APPROPRIATE SHOCK

00.10.20.30.40.50.60.70.80.9

1

0 1 2 3 4

Pro

bab

ility

of

Even

t-fr

ee S

urv

ival

Years of Follow-up

Ablation

AADHR 0.72 (95%CI 0.53, 0.98)

P=0.037

27.9 +/- 17.1 months follow-up

Ablation reduced rate of primary endpoint by 28% in comparison to

escalating antiarrhythmics, and had better side-effect profile(Primary Endpoint combination of death, VT and ICD therapies)

Hazard ratio 0.72

P=0.04

SUMMARY OF INDICATIONS FOR VT ABLATION

1. Patients with sustained monomorphic VT that recurs despite antiarrhythmic

drugs or when drugs are not tolerated or desired

2. Control of incessant sustained monomorphic VT or VT storm that is not due to a

transient reversible cause

3. Bundle branch re-entrant or interfascicular VT

4. Frequent PVCs, nonsustained or sustained VT in the setting of ventricular

dysfunction (and/or symptoms)

Dukkipati et al. JACC 2017:70:2924-41

SUMMARY OF INDICATIONS FOR VT ABLATION

5. Recurrent sustained polymorphic VT and VF that is refractory to

antiarrhythmic therapy and thought to be secondary to a trigger (i.e. PVC)

that is amenable for ablation.

6. Additionally, catheter ablation can be considered for sustained

monomorphic VT despite therapy with class I/III antiarrhythmic drugs

• As an alternative to amiodarone in patients with prior MI and LVEF >30%

• And as an alternative to antiarrhythmic drugs for hemodynamically

tolerated sustained monomorphic VT due to prior MI and LVEF > 35%

Dukkipati et al. JACC 2017:70:2924-41

ROLE OF CATHETER ABLATION IN VT WITH STRUCTURAL HEART DISEASE

Beta blockers + ICD

Add Sotalol or Amiodarone

Catheter

Ablation

Antiarrhythmics and

ablation may reduce

VT, but unclear if has

effect on mortality

Palliative vs Curative

Ongoing studies to

determine the best

course for these

patients

(i.e. VANISH 2)

VANISH

VANISH 2

EP Lab:

Mapping of Arrhythmia and

Scar/substrate.

Then ablation.

Using:

Voltage (and geometry)

Pace Mapping

Activation Mapping

Entrainment Mapping

Substrate

scar

Courtesy of Drs I. Kosmidou / W. Stevenson

Geometry and Voltage Map of Left Ventricle

Bipolar voltage:

Normal (purple) > 1.5mV

Border zone 0.5 – 1.5 mV

Scar (red/grey) < 0.5 mV

Can work inside the

geometry to minimize

fluoroscopy, mark relevant

features, and ablation lesions

Nazer et al Korean Circ 2014;44(4):210-217

GOALS OF VT ABLATION

• Ideally ablation of clinical VT (ECGs and ICD tracings)

• And any other induced VTs

• + Modification of substrate

• Regions of scar that still has electrical activity

• And plays critical role in the VT circuits

VT ABLATION OUTCOMESIN STRUCTURAL HEART DISEASE

• Success 50 – 77 % (over 1-2 years)

• Many remain on antiarrhythmic medications

• Complications up to 7%

• Stroke/TIA, perforation, vascular injury, hemodynamic decompensation

• Death up to 3% (sick patients usually)

• May need more than one ablation

• Mortality in one year follow up to 18%

• Recurrent VT or heart failure

Dukkipati et al. JACC 2017:70:2924-41

Nath et al. Prog in Card Dis 1995;37(4):185-204

Morady NEJM 1999;340(7):534-44

Highest

temperature

usually at 1mm

below tissue

surface

• Typical lesions (4mm electrode catheter)

• 2-3 mm depth and 5-6 mm diameter

• Larger lesions with cool-tip or larger electrode catheters (5-6mm depth)

Ablation

WHAT IF CIRCUIT IS NOT ACCESSIBLE ENDOCARDIALLY?

• Ablation depth

• Can limit ability to reach critical

isthmus

• Epicardial or mid-myocardial

EPICARDIAL ABLATION

• Described by Dr. Sosa (1996)

• Tuohy needle (used in epidurals)

• Advanced with minimal contrast injections

• If inadvertent RV puncture then pull back to

pericardial space

• Layering of contrast when in pericardium

Natale JCE 2010;21:339-379

TRANSCORONARYALCOHOL ABLATION

• Similar to HCM treatment

• Risk of heart block and deterioration of LV function

• Can be limited by lack of target vessels and collaterals

• Usually for deep septal circuits

• Cannot reach endocardially or epicardially

Brugada et al:Circ 1989; 79(3)

Sacher et al; Heart Rhythm 2008

Rarely used

NEEDLE CATHETERABLATION

(NOT EASILY AVAILABLE)

Deeper Lesions

FUTURE ?

• 24 Patients with VT after ablation

and anti-arrhythmics

• Stereotactic Arrhythmia

Radioablation (STAR)

Cuculich et al NEJM 2017:377:2325-36

Robinson et al. Circulation 2018

Similar to scar homogenization in

catheter ablation

Cuculich et al NEJM 2017:377:2325-36

Robinson et al. Circulation 2018

Di Biase et al JACC 2012;60:132-41

Stereotaxis Arrhythmia

Radioablation

(STAR ablation)

• Marked reduction in ventricular arrhythmias

• Collateral injury / side effects unknown

• Developing a research study (STAR VTM) looking at this in Calgary

MR. M

• Went to the EP lab and had three different VTs induced

• Extensive endocardial ablation on the substrate regions of the inferior and

anterior scar

• No inducible VT at end of case.

• Stayed on same medications

• On six month follow up no further VT

WHAT IF HE HAS MORE VT AFTER ABLATION?

• Add or increase antiarrhthmics

• Redo catheter ablation

• Not unusual to have more than one

• “Debulking”

• Same VT or new VTs

• Cardiac Transplant

• Palliation

• Other? (STAR)

CONCLUSION

• Definitely a reason for hope in VT management in structural heart

disease

• Ongoing development of cardiac medications, ICD, and ablation

technologies

Thank

You