1	Mapping Ventricular Tachycardia in Ischemic and Idiopathic Dilated CMP Moti Haim ,MD Cardiac Electrophysiology Service Belinson Campus Rabin Medical Center
2	Outline Pathophysiology-Mechanism of VT Mapping ECG Localization of VT Exit point Invasive mapping methods: Entrainment map Activation map Substrate mapping and ablation Management Medical ttx Ablation ICD
3	Pathophysiology Reentry –Most Common mechanism Triggered Activity Increased Automaticity
4	Reentry Requires: Slow Conduction Different Refractory Periods of adjacent myocardium Unidirectional block in one limb of the reentry circuit Scar provides perfect Substrate for block, slow conduction and variable refractory characteristics
5	Reentry
6	Reentrant VT Circuits
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9	VT in Ischemic and Non ischemic CMP
10	Mapping Principles
11	Mapping Purpose of VT mapping Recognizing the Mechanism (crucial for successful ablation and medical therapy) Localization Localization of the Critical Isthmus in Reentrant VT.
12	ECG Localization Limited in Pathologic heart (non uniform propagation, barriers in scar) Provides General Guide to Source Provides Estimate of Exit point to myocardium of reentrant circuit and does not provide data of rest of circuit
13	ECG Recognition of Exit Point of VT Inferior Axis- Anterior wall Superior Axis- Inferior wall Q waves across precordium- Apical R waves in V1/V2 – Basal LV LBBB Usually Septal (or rarely RV/ARVD) Typical LBBB - think of BBR (esepcially in non ischemic CMP) RBBB –Can be anywhere in LV (free wall/septum)
14	"Pathophysiology-Mechanism of Arrhythmia" Pathophysiology-Mechanism of Arrhythmia Mapping ECG Localization of VT InvasiveMapping Methods: Entrainment map Activation map Substrate mapping Management Medical ttx Ablation ICD
15	VT Examples ECGs
16	VT Examples ECGs
17	VT Examples ECGs
18	VT Examples ECGs
19	VT Examples ECGs
20	VT Examples ECGs
21	Outline Pathophysiology-Mechanism of Arrhythmia Mapping ECG Localization of VT Exit point Invasive mapping methods: Entrainment map Activation map Substrate mapping and ablation Management Medical ttx Ablation ICD
22	Entrainment Mapping
23	Resetting
24	Resetting without Fusion
25	Resetting with Fusion Possible only in Reentrant Circuit
26	Resetting with Fusion
27	Resetting Proof of Arrhythmia Mechanism
28	Resetting
29	Resetting
30	Resetting
31	Entrainment
32	Entrainment Map
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34	Progressive Fusion
35	Entrainment as tool to localize the critical isthmus
36	Identification of Potential Isthmus Sites Sinus EGMs Abnormal conduction is indicated by the presence of fractionated EGMs comprised of multiple low amplitude potentials Discrete low amplitude potentials are sometimes due to depolarization of an isthmus with surrounding areas of fixed block Late Potentials Limitation: Could be Innocent adjacent bystanders in scar
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38	EGMs During Tachycardia Middiastolic/ presystolic potentials at least 50 ms early then QRS (Josephson) An isolated, low amplitude, diastolic potential during VT potential is often a marker of a narrow isthmus in a reentry circuit Entrainment mapping is essential for determining if the isolated potential originates from the reentry circuit site as opposed to a bystander.
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40	Entrainment to localize Circuit
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42	Concealed Fusion using same exit site as VT
43	Entrainment Mapping of Critical VT Isthmus 1. Concealed Fusion – identical 12 lead ECG Morphology 2. PPI equals TCL (>=20 ms) 3. s-QRS = (>=20 ms)EGM-QRS
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45	S-QRS= EGM-QRS If pacing within the protected isthmus the s-QRS should equal EGM-QRS
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47	VT Case
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49	Entrance /Proximal Isthmus
50	Exit Point
51	Mid Isthmus
52	Substrate Based Mapping and Ablation
53	Substrate Based Mapping
54	Substrate Based Ablation
55	Electro-Anatomic Imaging RAO –Voltage Map
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58	"Electroanatomical Voltage map"
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62	Identifying Isthmus site with Pace Maps
63	Identifying Isthmus site with Pace Maps
64	Identifying Conducting Channels in scar
65	Targeting Late Potentials
66	SMASH-VT Trial
67	SMASH-VT Trial: Background The goal of the trial was to evaluate treatment with ICD implantation with catheter ablation compared with ICD alone among post myocardial infarction (MI) patients with sustained ventricular tachycardia (VT)/ ventricular fibrillation (VF)
68	SMASH-VT Trial: Study Design
69	SMASH-VT Trial: Primary Endpoint
70	SMASH-VT Trial: Adverse Events
71	SMASH-VT Trial: Summary Among post-MI patients with sustained VT/VF, ICD implantation with substrate-based catheter ablation was associated with a reduction in appropriate ICD therapy through two years compared with ICD therapy alone. The present trial suggests that the procedure can also be effective in reducing ICD shocks in the post-MI setting, although it should be noted that the procedure is difficult to perform and extremely technical, so use for prophylactic therapy should be undertaken with caution and only in experienced centers.
72	Ablation with Thermocool ablation catheter in Recurrent Ischemic VT
73	Bundle Branch Reentry
74	Bundle Branch Reentry