This double arm randomized study will compare 2 ventricular tachycardia ablation strategies: the standard strategy based on invasive substrate and VT mapping with 3D electro-anatomical system vs a tailored strategy which identifies targets based on pre-procedural CT-scan imaging. The primary endpoint will be procedure duration and secondary endpoints will include safety and efficacy criteria as well as medico-economic evaluation.

Ventricular tachycardia ablation is a non-drug alternative for patients with recurrent VT and ischemic cardiomyopathy with a class 1 indication in the latest guidelines. However, it is poorly standardised and reserved to expert centres. Proof of concept studies have demonstrated that image-guided VT ablation is feasible, and that it may improve the efficiency of VT ablation.

Ablation strategy no longer relying on intracardiac 2-dimensional surface catheter measurements for target identification, but on 3- dimensional pre-operative images of the myocardium acquired by computed tomography (CT) would shorten the procedure, make it more reproducible and less dependent of the operator's experience without altering efficacy.

This randomized study will compare VT ablation based on substrate/VT isthmus identification via intracardiac catheter vs identification via pre-procedural CT-scan. Ablation will be performed with the same material.

Primary endpoint will be procedure duration. Secondary endpoints will compare efficacy and safety of both strategies as well as cost-effectiveness.

Expected results are a reduction procedure duration, without alteration of the efficacy for the CT-guided procedure with an improved medico-economic evaluation.

Inclusion Criteria:

• Age ≥ 18 years,

• Indication for catheter ablation intervention with planned preoperative cardiac CT scan

• Prior myocardial infarction (using the international definition of MI: Q waves or imaging evidence of regional myocardial akinesis/thinning in the absence of a non- ischemic cause with documentation of prior ischemic injury),

• Presence of an implantable cardioverter defibrillator, or planned ID implantation before discharge, and

• One of the following monomorphic VT events within last 6 months:

  • A: ≥3 episodes of VT treated with antitachycardia pacing (ATP),
  • B: ≥1 appropriate ICD shocks,
  • C: sustained VT below detection rate of the ICD documented by ECG or any cardiac monitor
  • D: Sustained VT recorded on 12 leads ECG in the absence of ICD

• Highly effective contraception for women of childbearing potential, maintained during research procedures

• Signed informed consent ,

• Affiliated to or beneficiary of a health insurance

Exclusion Criteria:

• Unable to understand the nature, risks, significance and implications of the clinical investigation or unwilling to provide written informed consent,
• Active ischemia (acute thrombus diagnosed by coronary angiography, or dynamic ST segment changes demonstrated on ECG) or another reversible cause of VT (e.g. drug-induced arrhythmia), had recent acute coronary syndrome within 30 days thought to be due to acute coronary arterial thrombosis, or have CCS functional class IV angina. Note that biomarker level elevation alone after ventricular arrhythmias does not denote acute coronary syndrome or active ischemia,
• Are known to have protruding left ventricular thrombus or mechanical aortic and mitral valves,
• Have had a prior catheter ablation procedure for VT,
• Presenting arrhythmia: polymorphic VT or ventricular fibrillation (VF),
• Renal failure (Creatinine clearance <30 mL/min), have NYHA Functional class IV heart failure, or a systemic illness likely to limit survival to <1 year,
• Women who are pregnant, lactating, or who are planning to become pregnant during the anticipated study period,
• Patient under legal protection