Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Ablation Techniques D-PO02 - Poster Session II (ID 47) Poster

D-PO02-186 - Esophageal Temperature Monitoring Greatly Underestimates Esophageal Temperature Rises During High-power Short-duration Ablation As Compared To Standard Ablation (ID 245)

 A. Post: Nothing relevant to disclose.


Background: High power, short duration (HPSD) ablations are gaining popularity in treating atrial arrhythmias. However, little characterization has been performed on how heat transfer compares between HPSD ablations and standard ablations. This must be understood to avoid esophageal damage and subsequent atrioesophageal fistula formation.
Objective: Determine the thermodynamic differences between the HPSD and standard ablation techniques at different tissue interfaces.
Methods: Section of fresh porcine hearts and esophagi were secured to a custom holder and submerged in a temperature-controlled circulating water bath with a grounding pad at the bottom of the bath (Fig 1 A). Thermistors were positioned at the catheter tip-atrium interface, atrium-esophagus interface, and inside the esophagus lumen (Fig 1 B). Samples were tested in triplicate with varying ablation parameters: contact force (15-20g), power (10, 20, 30W), and duration (10, 20, 30s for standard; 5, 10, 15s for HPSD), all with irrigation. Temperatures were recorded until the temperature returned to 37C.
Results: The esophageal surface temperature was much higher than the lumen temperatures (Fig 1 C). The esophageal lumen reached peak temperature after the surface reached peak temperature (Delay averages - HPSD: 18.85s, Standard: 17.25s). HPSD also resulted in double the esophageal injury.
Conclusion: This suggests that the esophageal probe used in ablation underrepresents the esophageal surface temperature and lags significantly behind the actual esophagus heating. Particularly, further investigation is warranted for HPSD to determine optimal cut off temperatures to avoid esophageal injury risks.