This is a single-arm non-randomized prospective observational cohort study to assess the outcomes of patients undergoing intramural needle catheter ablation of recurrent ventricular tachycardia that has failed antiarrhythmic drug therapy and standard radiofrequency (RF) catheter ablation. Following ablation, patients will be monitored for 6 months. The duration of the study is up to 4 years.

This is an observational prospective cohort study of patients undergoing needle catheter ablation. Patients with recurrent sustained or incessant ventricular tachycardia who have recurrent monomorphic ventricular tachycardia that has failed antiarrhythmic drug therapy and prior catheter ablation who are undergoing intramural needle ablation for VT will be offered participation. Data will be collected during the procedure and during follow-up. Patients will be monitored in hospital for complications and during 6 months follow-up.

Data Collection:

Baseline Data: Baseline demographic information and a narrative medical history will be collected on all patients, including documentation of prior cardiac history, and arrhythmia history, as well as prior medications and cardiac procedures.

Procedural data: Details of the procedure including both procedural methods and arrhythmias induced, ablation parameters, needle deployments, recordings and response to procedure.

Followup data: Adverse events will be collected for events which are documented during enrollment and follow-up. During follow-up, hospitalizations will be collected, need for further procedures, implantable defibrillator therapies and procedures will be collected, as well as follow-up echocardiography findings.

Inclusion Criteria:

• Patients undergoing catheter ablation using the needle ablation catheter for ventricular arrhythmias.

Exclusion Criteria:

• Patient refusal to participate

Patients with recurrent ventricular tachycardia who have failed radiofrequency catheter ablation who are undergoing intramural needle catheter ablation procedures.