Safety and Performance Assessment of the Sphere-9™ Catheter and Affera™ Ablation System for the Treatment of Ventricular Tachycardia

Sphere-9 VT is a prospective, multi-center, non-randomized, unblinded feasibility study. Adult subjects with recurrent, sustained, monomorphic ventricular tachycardia due to prior myocardial infarction will be enrolled and treated with the Sphere-9 Catheter and Affera Ablation System.


Eligibility Criteria:
Inclusion Criteria:

1. Prior myocardial infarction.
2. At least one episode of sustained (continuous for \>30 seconds, or requiring implantable cardiac defibrillator intervention for termination) monomorphic ventricular tachycardia within the 6 months prior to enrollment.
3. Spontaneous occurrence of sustained ventricular tachycardia despite class I or III antiarrhythmic drug therapy or implantable cardiac defibrillator intervention.
4. Implanted with an implantable cardiac defibrillator or cardiac resynchronization therapy defibrillator for at least 3 months prior to the ablation procedure.
5. Age 18 through 85 years old.
6. Willing and able to provide informed consent.
7. Willing and able to comply with all pre-, post-, and follow-up testing requirements.

Exclusion Criteria:

1. Incessant ventricular tachycardia necessitating hemodynamic support prior to the ablation procedure.
2. Unstable polymorphic ventricular tachycardia or ventricular fibrillation.
3. Idiopathic ventricular tachycardia or ventricular tachycardia of non-ischemic cardiomyopathy.
4. Known reversible cause of ventricular tachycardia (e.g., electrolyte abnormalities, drug induced arrhythmia).
5. Ventricular tachycardia or ventricular fibrillation thought to be from channelopathies.
6. More than one prior ventricular tachycardia ablation at any time, or any ventricular tachycardia ablation within 6 months prior to the ablation procedure.
7. Unstable angina.
8. Active myocardial ischemia.
9. Type 1 myocardial infarction within 2 months (60 days) prior to the ablation procedure.
10. Any percutaneous coronary intervention within 2 months (60 days) prior to the ablation procedure.
11. Any cardiac surgery within 3 months (90 days) prior to the ablation procedure.
12. Left ventricular ejection fraction \<15%.
13. New York Heart Association Class IV heart failure.
14. Decompensated heart failure.
15. Currently receiving support, or anticipated to receive support prior to the index ablation procedure, via extracorporeal membrane oxygenation.
16. Ventricular assist device implanted, planned or required for the procedure.
17. Severe aortic stenosis or flail mitral valve.
18. Presence of prosthetic valve in the aortic or mitral valve.
19. Patients with advanced chronic obstructive pulmonary disease (on home oxygen).
20. Presence of intracardiac thrombus, tumor, or other abnormality that precludes vascular access, catheter introduction, or manipulation.
21. Thromboembolic event (stroke or transient ischemic attack) within 6 months (180 days) prior to the index ablation procedure or with neurologic deficit.
22. Intracardiac thrombus on imaging.
23. Severe bleeding, clotting or thrombotic disorder, or thrombocytopenia (defined as platelet count \<80,000).
24. Contraindication to anticoagulation.
25. End-stage renal disease (requiring dialysis).
26. Acute illness, active infection, or sepsis.
27. Life expectancy less than 12 months.
28. Any woman known to be pregnant or breastfeeding, or any woman of childbearing potential who is not on a reliable form of birth regulation method or abstinence.
29. Body mass index \>45 kg/m².
30. Known ongoing drug or alcohol dependency.
31. Current or anticipated participation in any other ongoing study of a drug, device, or biologic during the duration of the study not pre-approved by the Sponsor.
32. Vulnerable subjects (such as a prisoner, handicapped or mentally disabled person, or person under tutelage or guardianship).
33. Any other condition that, in the opinion of the investigator, would preclude enrollment in this study or compliance with follow-up requirements or would pose a significant hazard to the subject if an ablation procedure were performed.