Peri-Procedural Transmural Electrophysiological (EP) Imaging of Scar-Related Ventricular Tachycardia

Electrocardiographic imaging (ECGi) is an emerging technique to image cardiac electrical activity through inverse reconstructions from body-surface ECGs. After 40 years of active research, the potential of ECGi as a noninvasive adjunct to catheter mapping is gaining rapid attention in the clinical community.

A total of 40 consecutive post-infarction VT patients will be prospectively enrolled and recruited from those who have been referred for catheter ablation of scar-related VT. Within 7 days before the ablation procedure, these patients will undergo noninvasive cardiac CT or MRI imaging and noninvasive programmed stimulation (NIPS) study with simultaneous 120-lead body- surface ECG mapping (pre-ablation NIPS). MRI will be performed for patients with implantable defibrillators for whom it is considered safe to do so. CT imaging will be performed for those with Implantable Cardioverter Defibrillators (ICDs) which are not MRI compatible.

At the time of scheduled ablation, all patients will undergo standard catheter mapping and ablation procedure as a part of standard care. Within 7 days after the ablation procedure, the patients will undergo cardiac MRI imaging and noninvasive programmed stimulation (NIPS) with simultaneous 120-lead body-surface ECG mapping (post-ablation NIPS). For patients who cannot undergo MRI, CT imaging will not be repeated.

At 6 months after the procedure, a follow-up will occur as a part of standard care where outcome data regarding the chronic success of the ablation procedure will be collected and ICD interrogation will be performed. No imaging or mapping is planned at the follow-up.

Inclusion criteria

• One or more episodes of sustained monomorphic VT
• Referred for catheter ablation
• Previously implanted ICD
• Signed the patient informed consent form
• Able and willing to comply with all pre-, post-, and follow-up testing and requirements

Exclusion criteria

• Have estimated Glomerular Filtration Ratio (eGFR) less than 30
• Have a life expectancy less than 6 months or are listed for heart transplantation at time of inclusion
• Are pregnant
• Are on IV inotropic agents
• Have any contraindication to catheter ablation (including but not limited to mechanical prosthetic aortic and mitral valves, known protruding Left Ventricular (LV) thrombus
• New York Heart Association (NYHA) functional class IV
• Had ST wave elevation myocardial infarction within < 1 month
• Unwilling or unable to undergo cardiac MRI scan AND unwilling or unable to undergo cardiac CT scan (e.g. contrast allergy).