Programmed electrical stimulation and electroanatomical mapping in patients with non-ischemic cardiomyopathy

1. Dr Pasquale Vergara
DIAGNOSTICA NELLE CARDIOMIOPATIE NON ISCHEMICHE

2. The day and night of SCD prevention in NIDM
⇝SCD-HeFT 2005
2521 NYHA II/III patients & LVEF ≤ 35%
» conventional therapy + placebo
» conventional therapy + amiodarone
» conventional therapy + shock only ICD Death from any cause
Years
⇝DANISH 2016
1116 NYHA class II/III/IV (if CRT planned) & LVEF
≤35% & increased NT-proBNP

3. ⇝ICD implantation should be considered in patients with DCM/
HNDCM, NYHA class II–III, and LVEF ≤35% after ≥3months of OMT
Risk stratification in NICM
Arsenos P et al. World J Cardiol 2022; 14(3): 139-151
Zeppenfeld EHJ 2022
⇝ 2 limitations:
1. LVEF≤35% fails to identify truly arrhythmic risk
• the majority of the implanted ICDs are not expected to be activated
• as the recent DANISH study has shown, survival may not be improved
2. fatal arrhythmic events may occur in LVEF>35% NICM
patients

4. ⇝ In patients with SHD & mildly reduced/preserved LVEF who
present with unexplained syncope, induction of SMVT with PES can
be helpful to identify the underlying cause and to predict subsequent events
2022 ESC Guidelines for VA & SCD
⇝Voltage mapping, conduction/repolarisation metrics, and
electrogram fractionation can be employed to identify ablation
targets, or to diagnose cardiomyopathic disease
Zeppenfeld EHJ 2022
⇝ ICD implantation should be considered in DCM/HNDCM patients with a
LVEF<50% and ≥2 risk factors (syncope, LGE on CMR, inducible
SMVT at PES, pathogenic mutations in LMNA,d PLN, FLNC, and RBM20
genes)

5. The roadmap

6. VA induced by PES in Non-ischemic CMY Pogwizd Circulation 1998
Induced VA can arise in the
subendocardium or
subepicardium by a
focal
mechanism
39 plunge-needle electrodes
Patients undergoing OHT

7. Fibrosis in Non-ischemic cardiomyopathy Glashan EHJ 2018

8. Programmed ventricular stim in NICM Gatzoulis Circ Arrhythm Electrophysiol. 2013;6:504-512
ICD activation or SCD
158 NICM patients

9. VF induction by PES predicts recurrences in IDCM
⇝ 160 DCM patients
⇝ post spontaneous VT/VF
⇝ PVS + ICD implantation for secondary prevention of SCD
Rolf Europace 2009; 11, 289–296

10. Suggested NIDCM stratification Arsenos P et al. World J Cardiol 2022; 14(3): 139-151
Ischemic or non-ischemic cardiomyopathy patients
Left ventricular ejection fraction assessment
LVEF<35% LVEF  35%
competing mortality
<= 1 yr
survival
expectancy
>1 yr survival
expectancy
nothing
<3NIRFs >=3NIRFs
ICD
PES - PES +
Follow-up
High Low
<3NIRFs >=3NIRFs
PES - PES +
Follow-up ICD
NIRFs Imaging
Significant fibrosis
No Yes
PES - PES +
ICD
Follow-up
No NIRFs 1
PES - PES +
ICD
Follow-up
Late potentials @ SAECG 2/3 criteria
QTc interval duration  440M, 450F
PVBs ≥30/24 h
NSVT ≥ 1 episode/24 h
heart rate variability (SDNN) <=75ms
deceleration capacity of heart rate (DC) ≤ 4.5 m
heart rate turbulence (HRT) HRT onset ≥0%, slope ≤ 2.5ms
T-wave alternans (TWA) ≥65 μV (2-channels)

11. MRI and in-silico PES for NIDCM Balaban JACC 2021;7: 238 – 49
LV myocardium
LV scar
LGE / myocardium
interface
156 NICM patients
• 16 patients (10.3%) had
sudden death or
ventricular tachycardia

12. MRI and in-silico PES for NIDCM Balaban JACC 2021;7: 238 – 49
Interface
area
in-silico
PES

13. The roadmap

14. P. Vergara, et al. CircAE 2018;11:e006730
for the International VT Ablation Collaborative Group
I-VT Score
predicting VT ablation outcome
www.vtscore.org

15. None
0.36; 17/161
Age<65
0.93;
41/166
Yes
5.2;
30/39
No VT, NT,
NC-VT,
0.26; 11/147
C-VT
1.8;
6/14
Age≥65
1.5;
82/230
No
2.3;
16/34
ICD, CRT
0.82;
130/580
LVEF≥30
0.71; 147/741
LVEF<30
1.5; 169/469
PES?
PES
No VT, NC-VT
1.2; 123/396
NT, C-VT
3.8; 46/73
Device?
Previous Abl?
Age?
1;
316/1210
Hazard Ratio;
pts with event/pts in the group
LVEF?
Risk of VT recurrence re-estimated after ablation Vergara CircAE 2018;11:e006730

16. DM
2.4;
30/103
LVEF<14
5.3;
8/9
No
0.09;
4/404
Prev-Abl
0.44;
11/217
Age≥80
2.6;
8/25
LVEF≥30
0.19; 15/621
LVEF<30
2; 134/589
No VT
1.2; 55/370
No DM
0.75; 25/267
Age<80
0.56;
17/242
Previous Abl?
DM?
Age?
LVEF≥14
2;
26/115
ES
4.7;
45/95
NT, NC-VT, C-VT
3.5; 79/219
No ES
2.5; 34/124
EF?
ES?
PES?
1;
149/1210
Hazard Ratio;
pts with event/pts in thegroup
LVEF?
Risk of death re-estimated after ablation Vergara CircAE 2018;11:e006730
Re-stratification after the procedure

17. The roadmap

18. Characterization of the electrophysiological
substrate in patients with Barlow's disease Vergara JCE
2021;32:3179–3186.
2 ventricular fibrillation
2 VT sustained not tolerated

19. Electroanatomical mapping in Barlow’s dis
Bipolar Unipolar
Patients with previous SCD had larger Bi<1.5mV (4.5 ± 0.7 cm2) and Uni<8.3 mV areas
(32.8 ± 3.1 cm2), compared with patients without SCD (0.8 ± 1.6 cm2, p = .008 and 9.2 ± 8.7 cm2, p = .002).
The three patients without any Bi or Uni low voltage areas had less than or equal to 5000
PVCs/24; only one of them had NSVT; none had SCD; none had VA induction by PES.
Vergara JCE
2021;32:3179–3186.

20. ECGI: Electric substrate in a healthy adult
Andrews
CircAE 2017;10:e005105
Activation Recovery intervals
~ Repolarization
Abnormal conduction
~ reentry

21. ECGI: Advanced RV substrate in ACM
Activation Recovery intervals
» earliest activation originating from the basal inferior LV (*)
» Normal unipolar electrograms
» activation-recovery interval (ARI) values were prolonged
Andrews
CircAE 2017;10:e005105

22. CONCLUSIONI
⇝ La stratificazione del rischio aritmico nei pazienti con
cardiopatia non ischemica è tuttora imprecisa
⇝ Lo studio elettrofisiologico può avere un ruolo nell’identificare
I pazienti a maggior rischio di sviluppare eventi aritmici
⇝ Lo studio elettrofisiologico ha un ruolo nella stratificazione dei
pazienti sottoposti ad ablazione transcatetere di TV
⇝ Il mapaggio elettroanatomico può fornire informazioni cliniche
importanti in settings di pazienti selezionati, ma la sua invasività ne
limita l’utilizzo routinario