Esophageal Heating and Damage With High-Power-Short-Duration Radiofrequency and Pulsed Field Ablation

High-power short-duration (HPSD) radiofrequency ablation (RFA) and pulsed-field ablation (PFA) are intended to limit esophageal damage. The actual esophageal heating and damage risk are unclear.

This study sought to assess luminal esophageal temperature (LET) kinetics and esophageal risk of HPSD and PFA.

Included in this study were: 1) in vivo swine undergoing pulmonary vein ablation adjacent to the esophagus, using SmartTouch SF (STSF) (50W/10s, n = 8), QDOT (90W/4s, n = 8); or PFA (n = 12) using STSF Dual Energy or Omnypulse (OMNY) catheters (Biosense Webster); and 2) ex vivo swine esophagi. We collected LET, LET rise rate (dT/dt), postablation LET rises, and histology of the esophagus acutely and after 1 month.

Peak LET and dT/dt were higher in 50W/10s vs 90W/4s (41.8 ± 2.8 °C vs 39.7 ± 1.2 °C; P = 0.001). The bulk of LET rises with 90W/4s were postablation LET rises. All RF-ablated pigs had acute esophageal lesions, but only 50W/10s led to mucosal lesions or persisted after 1 month. Lesions after 90w/4s were limited to the muscularis externa. For PFA, peak LET and dT/dt were higher in STSF (40 ± 1.6 °C) vs OMNY (37.8 ± 0.7 °C; P = 0.001; maximum LETs: 43.8 °C and 39.2 °C, respectively). Acute muscularis externa lesions were observed in 4 of 4 pigs with STSF and 3 of 4 with OMNY, irrespective of LET rises. There were no detectable lesions at 30 days with PFA using either catheter design. Ex vivo experiments showed comparable LET rises for RFA and PFA-STSF.

LET rises and acute esophageal damage can occur with RFA-HPSD and PFA. However, PFA-induced esophageal damage was independent of PFA thermal effects and not detectable at 30 days.