Ischemic Cardiomyopathy, Nonischemic Cardiomyopathy, Ventricular Tachycardia (VT)
Conditions
Keywords
Ventricular tachycardia, substrate, mapping, reentry, cardiomyopathy, pacemapping
Brief summary
The goal of this study is to map conducting channels within scar that cause ventricular tachycardia (VT) in patients with scar in their hearts in order to block these channels from causing VT with targeted radiofrequency ablation (cautery). Participants undergoing VT ablation mapping of these channels by pacing many sites within the scar area and determining where these channels exit the scar into normal tissue. These exits will be ablated. Immediate success and success at 1 year will be evaluated.
Detailed description
After standard VT induction and mapping procedures (noninvasive identification of induced VT exit sites with Vektor vMap; substrate mapping; initial pacemapping), the study will consist of pacing within the substrate and mapping all channel exits both noninvasively with vMap as well as invasively with high density mapping catheters within the heart by escape mapping (all paced sites creating a consistent paced morphology, up to the shortest stimulus-to-QRS interval achieved) as well as focal activation mapping of this channel exit while pacing within the channel. The noninvasive map will aid in focusing invasive mapping to a small area of the substrate. Once the exit sites are determined, ablation energy will be delivered based on the mapped exit sites in the substrate channel within 0.5cm of the exit with the goal of blocking each exit site mapped. After the ablation lesion set is delivered, repeat attempt to induce VT will be performed. If more VT is induced, additional ablation energy will be delivered guided by standard mapping techniques (substrate, slow conduction zones, pacemapping).
Interventions
PROCEDURESelective Substrate Isolation
Ablation will be guided by mapping the substrate "from the inside out" by identifying conducting channels as they might be activated during VT. Extensive pace mapping will be performed within scar areas identified during sinus rhythm mapping. The course of these channels will be identified and ablated across the distal portion, just proximal to the exit based on shortest stimulus-to-QRS interval obtained.
Sponsors
New York Medical College
Study design
Observational model
CASE_ONLY
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients with structural heart disease undergoing VT ablation
Exclusion criteria
1. Unable or unwilling to sign consent 2. Cardiogenic shock or NYHA Class IV heart failure and not a candidate for mechanical circulatory support for the procedure (percutaneous left ventricular assist device (LVAD), extracorporeal membrane oxygenation, or implanted LVAD) 3. Absence of substrate during initial voltage mapping
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of participants achieving substrate Isolation with ablation of exit sites | Perioperative/Periprocedural: This will be measured at the end of the study ablation procedure only. | Inability to stimulate the ventricle (physiologic parameter) while pacing in the substrate area contained by the ablation lines through each pacemap exit, at sites that were able to stimulate the ventricle prior to ablation. This will be manifest by the absence of a QRS complex resultant from the pacing stimulus. This is a |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| VT invasive map exit and vMap exit match | Perioperative/Periprocedural: This will be measured throughout the study ablation procedure. | Percent matching of VT exits determined by activation/entrainment/pace mapping for matched ECG morphologies with vMap determined exits |
| Channel exit and vMap match | Perioperative/Periprocedural: This will be measured throughout the study ablation procedure. | Percent matching of noninvasively mapped exit sites compared with invasively mapped channel exits |
| Inducibility post initial ablation | Perioperative/Periprocedural: This will be measured during the study ablation procedure, after the first set of radiofrequency lesions is placed based in initial mapping. | VT inducibility after first lesion sets determined by channel mapping |
| 1 year outcome | 1 year: This will be measured for each subject up to 1 year after the study procedure. | VT recurrence at 1 year determined by therapies delivered by implantable cardioverted defibrillator and presentation with sustained VT below ICD detection. |
Countries
United States
Outcome results
None listed