The purpose of this study is to determine if early ablation (i.e., ablation of ventricular tachycardia in patients with infrequent VT episodes) is more effective than medical therapy alone for the treatment of ischemic ventricular tachycardia in patients with Implantable Cardioverter Defibrillators (ICDs) who continue to have episodes of ventricular tachycardia despite drug therapy.

Inclusion Criteria:

1. Subject must be drug refractory on Class I-IV AADs (i.e., having VT episodes despite drug therapy)

   a. Subject must be on at least one AAD at time of enrollment

2. Qualifying episode must be sustained, monomorphic Ventricular Tachycardia post myocardial infarction

3. ICD implanted

4. 1 to 3 sustained monomorphic VT episodes requiring appropriate therapy within the previous six (6) months as determined by the investigator

5. History of myocardial infarction documented by the development of pathological Q waves with or without symptoms, imaging evidence of a region of loss of viable myocardium that is thinned and fails to contract in the absence of a nonischemic cause, or pathological findings of a healed or healing myocardial infarction

6. 18 years or older

7. Able and willing to comply with all pre- and follow-up testing and requirements

8. Signed Informed Consent Form

Exclusion Criteria:

1. Age < 18 years
2. Documented intra-atrial or ventricular thrombus or other abnormality on preablation echocardiogram
3. Patients with Incessant Ventricular Tachycardia (continuous sustained VTs that recur promptly despite repeated intervention for termination over several (≥ 3) hours)
4. Contraindication to anticoagulation
5. NYHA class IV
6. Left ventricular assist devices (LVADs) or other circulatory assist devices
7. Stroke as confirmed by plasma d-dimer levels or acute myocardial infarction as documented by electrocardiogram or cardiac imaging within the past three (3) months. (Note that a small cardiac enzyme release resulting from being in VT/shocks/etc. is not considered a myocardial infarction.)
8. Patients with active ischemia who are eligible for revascularization
9. Patients with idiopathic Ventricular Tachycardia or Ventricular Tachycardia of non-ischemic cause (such as nonischemic cardiomyopathy)
10. Other disease process likely to limit survival to less than 12 months
11. Serum creatinine of ≥ 2.5mg/dl
12. Thrombocytopenia or coagulopathy
13. Prior ablation for Ventricular Tachycardia
14. Women who are pregnant (as evidenced by pregnancy test if pre-menopausal)
15. Enrollment in an study evaluating an investigational device or drug
16. Unable or unwilling to comply with protocol requirements
17. Exclusively Polymorphic Ventricular Tachycardia

There IS an agreement between the Principal Investigator (PI)/Institution and the Sponsor (or its agents) that restricts the PI's rights to discuss, present or publish trial results after the trial is completed. Please contact Biosense Webster, Inc. for additional information.