Determination of Continuity Index Values in Atrial Fibrillation Ablation with Proactive Esophageal Cooling
April 19th, 2024
This protocol describes the methods used to determine the continuity index in patients undergoing pulmonary vein isolation procedures using radiofrequency ablation and demonstrates the differences in continuity index between ablation procedures using proactive esophageal cooling as compared to procedures using traditional luminal esophageal temperature monitoring.
This protocol describes the methods used to determine the continuity index in patients undergoing pulmonary vein isolation procedures using radio frequency ablation, and demonstrates the differences in continuity index between ablation procedures using proactive esophageal cooling, as compared to procedures using luminal esophageal temperature monitoring. Proactive esophageal cooling using a dedicated device has been granted marketing authorization by the Food and Drug Administration to reduce the likelihood of ablation-related esophageal injury, resulting from radio frequency ablation procedures, and long-term follow-up data suggests improved freedom from arrhythmia when using cooling, as opposed to LET monitoring. Ablation and mapping catheters provide a variety of lesion quality markers, including impedance decline, catheter tissue contact force, catheter stability, and bipolar electrogram amplitude reduction, which serve as evidence of transmural contributing to PVI effectiveness.
However, continuity index is not a marker provided by current devices and technologies, and currently requires manual assessment. Proactive esophageal cooling allows for a contiguous placement of sequential lesions without interruption or the need to pause for local overheating or temperature alarms. This, in turn, decreases operator cognitive load and procedure time, and allows for increased lesion continuity, or low continuity index, potentially increasing long-term PVI success.
Low continuity index as a result of cooling may not only increase the durability of lesions, resulting in a higher freedom from arrhythmia, but also minimizes risks of thermal injury to critical structures that remains when using reactive luminal esophageal temperature monitoring, and eliminates the need for deviation of critical structures.
Overview
This protocol describes methods for determining the continuity index in patients undergoing pulmonary vein isolation procedures using radiofrequency ablation. It highlights differences in continuity index between proactive esophageal cooling and traditional luminal esophageal temperature monitoring.
Key Study Components
Area of Science
- Cardiology
- Electrophysiology
- Medical Devices
Background
- Proactive esophageal cooling has FDA marketing authorization.
- It reduces the risk of ablation-related esophageal injury.
- Long-term follow-up suggests improved freedom from arrhythmia with cooling.
- Continuity index requires manual assessment and is not provided by current devices.
Purpose of Study
- To evaluate the impact of proactive esophageal cooling on continuity index.
- To compare outcomes of different ablation monitoring techniques.
- To assess the potential for increased lesion continuity and PVI success.
Methods Used
- Radiofrequency ablation procedures were performed.
- Continuity index was manually assessed.
- Comparative analysis between proactive cooling and traditional monitoring was conducted.
- Lesion quality markers were evaluated during procedures.
Main Results
- Proactive cooling resulted in a lower continuity index.
- Improved lesion continuity was observed with proactive cooling.
- Reduced operator cognitive load and procedure time were noted.
- Higher freedom from arrhythmia was associated with cooling techniques.
Conclusions
- Proactive esophageal cooling enhances PVI effectiveness.
- It minimizes risks of thermal injury compared to traditional methods.
- Continued research is needed to validate these findings.
Frequently Asked Questions
Executive Industry Relevance
Quantitative assessment of lesion placement continuity during pulmonary vein isolation (PVI) is critical for optimizing ablation efficacy and minimizing collateral injury. The continuity index (CI) provides a reproducible metric for evaluating procedural precision, supporting predictive confidence in long-term arrhythmia management. Integrating CI measurement into ablation workflows enables more informed risk-adjusted decisions and enhances portfolio-level procedural standardization.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Enables mechanistic de-risking by quantifying lesion contiguity during ablation.
- Supports functional validation of device-mediated esophageal protection strategies.
- Facilitates predictive confidence in procedural endpoints for device development.
Screening & Assay Development
- Establishes a standardized metric for evaluating ablation system performance.
- Enables reproducible comparison of lesion quality markers across device platforms.
- Supports assay readiness for downstream device and procedural optimization studies.
Translational & Preclinical Research
- Aligns procedural metrics with translational endpoints relevant to clinical device adoption.
- Provides continuity from benchtop validation to preclinical and clinical device evaluation.
- De-risks advancement of esophageal protection technologies by quantifying procedural impact.
Pipeline & Workflow Integration
The CI metric integrates into the ablation workflow from early device validation through clinical implementation, supporting iterative optimization and cross-study comparability.
- Discovery Biology: Quantifies procedural precision and lesion contiguity for hypothesis-driven device evaluation.
- Screening: Enables reproducible, quantitative assessment of ablation system performance and procedural consistency.
- Analytics: Provides a standardized output for comparing device-mediated procedural outcomes.
- Translational Research: Bridges preclinical findings with clinical procedural endpoints for device adoption.
- Enterprise Reuse: Establishes CI as a reusable metric for ongoing device and procedural innovation.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence in ablation durability and safety.
- Operational Value: Standardizes procedural assessment and reduces operator variability.
- Strategic Value: Informs go/no-go decisions for device advancement and procedural adoption.
- Portfolio Impact: Supports risk-adjusted prioritization of device and procedural innovations.
Implementation Considerations
- Requires operator expertise in manual CI assessment and lesion mapping.
- Depends on integration with ablation and mapping catheter technologies.
- Necessitates cross-team agreement on CI calculation and reporting standards.
- Adaptable to both prospective and retrospective procedural data analysis.
- Manual assessment may limit scalability until automated solutions are developed.
Biopharma FAQs
Chapters in this video
0:00
Introduction
2:02
Continuity Index (CI) Calculation for Prospective Cases of Atrial Fibrillation Ablation with Proactive Esophageal Cooling
3:00
Continuity Index (CI) Calculation for Retrospective Cases of Atrial Fibrillation Ablation with Luminal Esophageal Temperature (LET) Monitoring
