Conflicts Indications for Use of Endocardial and Epicardial - - PDF document

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Ablation of Ventricular Tachycardia: Indications for Use of Endocardial and Epicardial Approaches

Edward P Gerstenfeld MD Professor of Medicine University of California, San Francisco

UCSF

Conflicts

Ø Biosense-webster: research grant, honoraria Ø Medtronic: research grant, honoraria Ø St Jude Medical: research grant, honoraria Ø Boston scientific: honoraria Ø Rhythm diagnostic systems: advisory board

VT Ablation in Post-infarction Cardiomyopathy

N =81,539

Palaniswamy C. Heart Rhythm 2014;11:2056

Catheter ablation increased from 2.8% (2002) à 10.8% (2011) (p <0.001).

deBakker J. Circulation 1988; 77:589

Slow conduction in the infarcted tissue, with ‘zigzag' course of activation Tung R. Circulation 2011;123:2284

Anatomic Substrate in Post-Infarction VT

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VT Ablation in Post-infarction Cardiomyopathy

Ø 90% macroreentrant, scar based Ø 10% focal (automatic or triggered)* Ø Tolerated VT – entrainment mapping Ø Non-tolerated VT – substrate based ablation

*Das et al Heart Rhythm 2010;7:305-11

Mapping VT in CAD

480ms 480ms

Inner Loop

* *

*

57 yo with VT 7 years s/p ASMI

Ablds Ablpx RVa I II III aVR aVL aVF V1 V2 V3 V4 V5 V6 I II III AVR AVL AVF V1 V2 V3 V4 V5 V6 Hisd RV Hisp Abld Ablp Stim

VT Termination with RF

Outcome After Ablation of Mappable VT

Soejima et al Circulation 2001;104:664-669

28% Arrhythmia recurrence

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But….

• Only ~10% of VTs are tolerated

>1.5 mV <0.5.mV Late potentials scar normal

AP LAO

border

Bipolar LV Voltage Map After Anterior MI

normal scar

Pacemaps matching VT

Case

Ø A 64 yo male with HTN suffers an anterior MI 7 years ago Ø Treated with ASA, metoprolol, lisinopril Ø Echocardiogram with EF 40% Ø Now presents to ER with VT. Cardioverted. Do you recommend: a) Implant ICD b) Amiodarone 200mg qd + ICD c) Catheter ablation + ICD

VTACH Study

Kuck et al. Lancet 2010;375:37-40.

29% 47% Ø 107 pts. with stable VT, prior MI and LVEF<50% prospectively randomized to ICD or VT RFA + ICD Ø Entrainment, activation, pace-mapping, substrate modification

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Case

Do you recommend: a) Implant ICD b) Amiodarone 200mg qd + ICD c) Catheter ablation + ICD

Case

Ø A 68 yo male has a history of AMI and VT Ø Single chamber ICD placed Ø Treated with ASA, metoprolol, ramipril, amiodarone 200mg qd Ø Echocardiogram with EF 30-35% Ø Presents with 2 appropriate ICD shocks for MMVT Ø Cath: no new coronary artery disease Do you recommend: a) Reload and increase amiodarone to 400mg qd b) Add Mexiletine 150mg tid c) Catheter ablation d) Transplant evaluation

Ventricular Tachycardia Ablation or Escalated Drug Therapy (VANISH)

Ø Pts with ICM + VT randomized to escalated AAD therapy (Amio 200mg, I amio if<300mg, or + Mexiletine) vs. cath RFA Ø Primary outcome: death, VT storm, or appropriate ICD shock

Sapp J. N Engl J Med, 2016. 375(2):111-121.

Primary outcome = 59.1% (RF group) Vs. 68.5% (Esc- AAD group) >

N=259- 132 Abl vs. 127 AAD

Ventricular Tachycardia Ablation or Escalated Drug Therapy (VANISH)

Sapp J. N Engl J Med, 2016. 375(2):111-121.

Baseline Amio No Baseline Amio Complications: RFA: 2 perforations, 3 bleeding Esc-AAD: 2 deaths pulm toxicity and 1 death hepatic toxicity

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Case

Do you recommend: a) Reload and increase amiodarone to 400mg qd b) Add Mexiletine 150mg tid c) Catheter ablation d) Transplant evaluation

VT Ablation in NICM

UCLA: 6/2004-7/2011

Sacher F. Circ Arrhythm Electrophysiol 2008;1;153 Nakahara S. JACC 2010;55:2355–2365

Ø Catheter ablation increased from 27% (1999-2002) to 35% (2003-2006) (P=0.06)

Non-ischemic Cardiomyopathy

Ø Most common mechanism still reentrant MMVT Ø Automatic VTs also may also occur – effect of sedation/general anesthesia Ø Often multiple VTs, poorly tolerated Ø More often basal, perivalvular and epicardial origin

ICM

40.5% 43% 23% 57%

NICM

Outcomes in VT Ablation in Nonischemic vs Ischemic Cardiomyopathy Heart Centre of Leipzig VT (HELP-VT) Study

VT–Free Survival

Dinov B. Circulation. 2014;129:728-736

N=227: 63 NIDCM vs 164 ICM

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Why is Ablation More Difficult / Less Successful in LV DCM

• 1. Multiple VT morphologies
• 2. Epicardial / midmyocardial substrate

Septal Substrate for VT in Nonischemic Cardiomyopathy

Haqqani, H. Heart Rhythm, 2011; 8:1169 Hutchinson M. Card EP Clin, 2010; 2:93

Ø ~12% of NICM patients had isolated septal substrate, multiple unmappable VTs

Bipolar Unipolar

Scar Patterns in Nonischemic Cardiomyopathy

Piers, S. Circ Arrhythm Electrophysiol. 2013;6:875

RAO LAO

RV LV Liver Sternum

Subxyphoid Puncture– Epicardial Catheter Ablation

Sosa E JACC 2000;35:1450-52

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Epicardial Access

RAO LAO

Epicardial Mapping

RAO LAO

When to Consider Epicardial Access

• Substrate

– ARVC, DCM, Chagas, prior pericarditis

• ECG

– Inferior q waves, precordial pattern break

• Imaging

– MRI, ICE

• Patient characteristics

– Age, comorbidities, prior CABG/valve surgery, pectus, hepatic enlargement

When to Consider Epicardial Access

• Substrate

– DCM, ARVC, Chagas, prior pericarditis

• ECG

– Inferior q waves, precordial pattern break

• Imaging

– MRI, ICE

• Patient characteristics

– Age, comorbidities, prior CABG/valve surgery, pectus, hepatic enlargement

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CAD HOCM IDCM ARVC/D Sarcoid Focal/Normal 4 35 40 11 85 2

Epicardial VT Ablation After Failed Endocardial Ablation - Substrate (N=177)

UPHS database

38 yo with ARVC and ICD Shocks

>1.5 mV <0.5.mV

AP

ARVC Epi Voltage Map

>1.0 mV <0.5.mV

When to Consider Epicardial Access

• Substrate

– ARVC, DCM, Chagas, prior pericarditis

• ECG

– q waves inferior, V2, I, precordial “pattern break”

• Imaging

– MRI, ICE

• Patient characteristics

– Age, comorbidities, prior CABG/valve surgery, pectus, hepatic enlargement

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Site-specific Assessment of Epicardial VT Origin in DCM

Ø Fifteen patients with detailed endo/epi pacemapping and VT

LV Endocardium

Apex Apical Superior Basal Superior Basal Inferior Apical Inferior

Bazan, Gerstenfeld … Marchlinski; Heart Rhythm 2007;4:1403-10

Surface ECG in VT

II I

Site-specific Epi VT (Bazan) Criteria In The Absence of Prior MI

LV Endo

Apex Apical Superior Basal Superior Basal Inferior Apical Inferior No q II, III, aVF q wave I q wave I Q wave V2 QS II, III,aVF

Bazan, Gerstenfeld … Marchlinski; Heart Rhythm 2007;4:1403-10

Epicardial VT

Best PM VT1

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When to Consider Epicardial Access

• Substrate

– ARVC, DCM, HCM, Chagas, prior pericarditis

• ECG

– Inferior q waves, precordial pattern break

• Imaging

– MRI, ICE

• Patient characteristics

– Age, comorbidities, prior CABG/valve surgery, pectus, hepatic enlargement

MRI

Ø 48 yo presenting with MMVT Ø Mid-wall delayed enhancement noted in the inferolateral wall at the base with extension to the subepicardial region.

I II III aVR aVL aVF V1 V2 V3 V4 V5 V6

Intracardiac Echocardiogram When to Consider Epicardial Access

• Substrate

– ARVC, DCM, HCM, Chagas, prior pericarditis

• ECG

– Inferior q waves, precordial pattern break

• Imaging

– MRI, ICE, EAM

• Patient characteristics

– Age, comorbidities, prior CABG/valve surgery, pectus, hepatic enlargement

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Epicardial Puncture After Open-Chest Surgery

Surgical Window

VT Surgery - Cryoablation

LAA LCx and Plane of Mitral Valve Anter et al. Circulation EP 2011;1:494-500.

Outcome After Ablation in NICM

Tokuda M et al. Circ Arrhythm Electrophysiol. 2012;5:992-1000.

Limitations of Epicardial Ablation

• Access

– Risk of RV/LV perforation – Coronary vessel perforation – Liver/lung/bowel laceration – May not be accessible in prior CABG/valve surgery/ablation

• Ablation

– Fat, coronary vessels, phrenic nerve – Epicardial fluid accumulation – Catheter tip contact/orientation – Cardiac motion

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New Technology for VT Ablation

Ø HiFU ablation Ø Linear ablation

Epicardial HiFU Catheter

Ø 12 Fr OD nylon catheter housing

A-mode imaging transducer HIFU ablation transducer Radiopaque

• rientation

marker Internal irrigation balloon Nazer B, et al. Circulation Arrhythmia EP , 2015.

Not available for human use

Representative Lesions

47

10 mm Nazer B, et al. Circulation Arrhythmia EP , 2015.

HIFU Ablation Over LCX

48

10 mm 1 mm

250 μm

Nazer B, et al. Circulation Arrhythmia EP , 2015.

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HIFU Mean Lesion Sizes

49

RF 30W 20W 15W 5 mm Nazer B, et al. Circulation Arrhythmia EP , 2015.

Linear RF Catheter

Ø 7 externally irrigated 3 mm RF ablation electrodes Ø 5 mm spacing Ø 25 W max power, titrated individually to each electrode

50

nMARQ Not approved for human use

Linear vs Focal Ablation

51

B A

Focal Linear

Lesion Gaps

52

Focal RF

1 cm

1 cm

Linear RF Ø Gaps present in 53% focal lesions compared to 0% linear lesions

Nazer B et al. Heart Rhythm, in press

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Ablation Data

FOC (n=15) LIN (n=40) p-value #RF lesions per line 8.6 ± 2.0 1

• RF time (sec)

497 ± 111 56 ± 9 p < 0.0001 Power (W) 27 ± 6 23 ± 5 p < 0.0001 Impedance drop (Ω) 17 ±11 20 ± 13 p = 0.049 Irrigation infused (ml) 78 ± 39 39 ± 7 P < 0.0001 Nazer B et al. Heart Rhythm, in press

Guidelines for Catheter VT Ablation

ESC Guidelines for Management of Ventricular Arrhythmias 2015

Recommended

• 1. Patients with scar-related heart disease with incessant VT/ storm
• 2. Patients with ischemic heart disease & recurrent ICD shocks due to

VT

• 3. Patients with BBR VT
• 4. As additional therapy or an alternative to ICD in patients with CHD

with recurrent VT or ICD therapies refractory to drugs

Should be considered

• 1. After first sustained VT episode with ischemic heart disease and

ICD

• 2. May be considered in patients with DCM and VA refractory to

medical therapy.

• 3. In patients with LV dysfunction associated with freq PVCs, NSVT

Summary

Ø VT ablation should be considered prior to ICD placement in patients with ischemic cardiomyopathy presenting with stable MMVT Ø VT ablation should be considered first line therapy in pts with ischemic cardiomyopathy AND MMVT receiving ICD shock(s) Ø If using AAD to treat VT, consider starting with Sotalol Ø Epicardial access and mapping techniques have improved our ability to treat VT in patients with DCM. Additional risks and limitations of epicardial access need to be considered. Ø Newer technologies for VT mapping and ablation are still needed

Mahalo

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Prophylactic VT Ablation?SMASH-VT

Ø Prospective, Randomized Trial

Ø Assess safety/efficacy of “prophylactic” substrate ablation in preventing ICD shocks in post-MI patients who have sustained a VT/VF event

Ø 3-Center, Randomized Trial (127 pts)

Ø VF Arrest Ø Unstable VT Ø Syncope & Inducible VT Ø Remote ICD / Recent ICD Event

Ø Primary Endpoint: ICD therapy

Follow-Up (2 years) History of a MI (VT/VF) Randomization ICD ICD + VT Ablation (9%) (53%) (18%) (20%) Reddy et al NEJM 2007;357:2657-65.

SMASH-VT Results: ICD Shocks

Freedom from ICD Rx (%) Follow-Up (Months)

Ablation Control

6 12 18 24 20 40 60 80 100

(p = 0.003) 31.3 % 9.8 %

Reddy et al NEJM 2007;357:2657-65.