The EPISODE VT trial is designed to compare efficacy and safety of two modalities for interventional treatment - endocardial ablation and endo-epicardial ablation in a population of patients with post myocardial infarction (ICD 10 - I25.2) ventricular tachycardias (ICD 10 - I47.2), who are protected by an implantable cardioverter-defibrilator (ICD) and meet study inclusion criteria.

The EPISODE VT trial is designed to compare efficacy and safety of two modalities for interventional treatment - endocardial ablation and endo-epicardial ablation in a population of patients with post myocardial infarction (ICD 10 - I25.2) ventricular tachycardias (ICD 10 - I47.2), who are protected by an implantable cardioverter-defibrilator (ICD) and meet study inclusion criteria. Nowadays, most often ablation is performed using only endocardial approach. The rate of VT recurrences after such ablation may exceed 50%, which is largely due to the inability to remove all arrhythmogenic substrate. At the same time, in cases where all potentially arrhythmogenic substrate is removed, the immediate and long-term results are better, both in terms of recurrence and prognosis. Single reports on endo-epicardial ablation as the first-line therapy in patients with post-infarction VT indicate a higher efficacy of this approach compared to endocardial ablation. Similar conclusions emerge from meta-analyses. This is probably due to a more complete removal of the arrhythmogenic substrate located mainly in the epicardium or intramurally.

In the endo-epicardial group pericardial sac puncture will be performed after filling it with carbon dioxide, which creates a space for safe puncture.

Ablation procedures will be performed as standard. The electrophysiological systems and ablation electrodes used in the study will be standard devices that research centers are equipped with. Their use will be in accordance with the procedures of the center and the instructions for use.

Inclusion Criteria:

• Status after myocardial infarction (minimum 3 months before inclusion in the study).

• Documented post-infarction VT or VF.

• Implantable ICD (at least 2 weeks before ablation) or CRT-D (at least 2 months before ablation).

• A history of at least one from below:

  1. One or more high energy interventions.
  2. Three or more adequate antitachycardia pacing therapies, including one symptomatic.
  3. Three or more episodes of VT in 24 hours (interrupted by ATP or shock) - electrical storm.
  4. Sustained VT recorded on ECG with a cycle length longer than the ICD detection threshold.

• Age between 18 and 85 years.

• Signed informed consent to participate in the study.

Exclusion Criteria:

• Obesity with BMI > 40 kg/m2.
• Left ventricle ejection fraction < 20%.
• Pregnancy or breastfeeding.
• Renal failure (eGFR < 20 mL/min/1.73m2).
• Fresh ballot thrombus in the left ventricle.
• Suspicion of massive adhesions in the pericardium that may impede pericardial puncture.
• Ablation of the post-infarction VT in the left ventricle in medical history.
• Previous heart surgery.
• Acute conditions that prevent ablation (including active infection, overt hyperthyroidism and others listed below).
• Active neoplastic disease.
• Heart failure with NYHA IV.
• Life expectancy less than 12 months.