Influence of Ventricular Pacing on Automated Ventricular Substrate Mapping and Relationship Between Ablation Index and Impedance Drop in the Human Ventricle
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 15
- 试验地点
- 1
- 主要终点
- Areas with ventricular tachycardia substrate
研究概览
简要总结
There is an increasing evidence regarding the efficacy of a substrate-based ablation approach to ventricular tachycardia (VT). This approach involves identifying regions of scar and also areas displaying late potentials and fractionated activity. Automated mapping systems are now available which may be able to generate high density maps displaying regions containing both late potentials and ventricular scar. Such an automated approach has not been validated. Furthermore, most patients presenting for VT ablation have pacing devices in situ. It is not known how the pacing modality affect the substrate maps generated for these procedures. Once an area felt to be important to ablate has been identified, the next key step is to perform effective ablation. An algorithm has now been made available (Ablation index - Biosense Webster Inc.,) which in preclinical studies is an effective predictor of radiofrequency lesion depth. This algorithm has been studied extensively in the atrium but not in the ventricle. This study would also seek to collect ablation index data during ablation to assess the algorithm during ventricular ablation.
详细描述
The study would propose to use the Carto3 mapping system with the Confidense automated tagging module (Biosense Webster Inc.,) and a high density mapping catheter to generate substrate maps of the ventricle, with maps generated with varying pacing modes. A SmartTouch catheter (Biosense Webster Inc.,) would then be used for ablation with data collected during each ablation.
The study hypotheses are:
- High density automated mapping systems can be used to generate accurate ventricular substrate maps.
- There will be a significant change in the late potential maps based on the presence and type of ventricular pacing.
- The relationship between impedance drop and ablation index during ablation will be stronger than FTI and will allow formulation of an upper limit for clinical ventricular ablation.
- The relationship between FTI and AI with impedance drop will be stronger than with electrogram attenuation.
Protocol:
15 patients, listed on clinical grounds for a left ventricular VT ablation in the context of structural heart disease (including redo ablation) would be recruited for the trial. All patients would need to have a pacing device in situ and have underlying sensed ventricular rhythm (with or without atrial pacing), or in the absence of a sensed ventricular rhythm, a biventricular pacing device. As part of their clinical work-up for the procedure, patients will have cardiac MRI scans wherever possible.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Diagnostic
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 100 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Ventricular Tachycardia; scheduled for ablation on clinical grounds; able/willing to consent to procedure/research protocol; no contraindication to clinical ablation; ≥18 years old
排除标准
- •Unable/unwilling to consent; contraindication to clinical ablation
研究组 & 干预措施
Mapping and ablation
Automated Substrate maps with different pacing modes. Validation of collected substrate. Data collection during ablation
干预措施: Mapping and ablation (Device)
结局指标
主要结局
Areas with ventricular tachycardia substrate
时间窗: Through study completion, an average of 1 year
Quantification of late potential area and scar area with comparison between pacing modalities
次要结局
- Relationship between ablation index and impedance drop(Through study completion, an average of 1 year)
- Relationship between Force Time Integral and impedance drop(Through study completion, an average of 1 year)
- Relationship between electrogram attenuation and impedance drop(Through study completion, an average of 1 year)