E25

Response to Letter to the Editor

To the Editor

Thank you for giving us the opportunity to respond toDr. Feld’s valid concerns.1 As stated in the article, the ab-lation strategy was altered when heating was encounteredalong the posterior wall.2 Specifically, in addition to limitingpower to 25 Watts and duration to 30 seconds, the catheterwas moved away from the esophagus along with a furtherdecrease in power and/or duration of ablation lesions. Webelieve the need to move further away from the esophagusgiven the increased temperature rises may have contributedthe increased ablation time in the multisensor probe group.Although it is reasonable to assume that increased ablationtime would lead to more injury, this was not found in 2 priorstudies investigating patient and procedural characteristicsbetween those with esophageal injury and those without.3,4

Furthermore, as shown in Table 3 of our article, there wasno significant difference in total energy applied in those withinjury and those without injury among those who had anesophageal endoscopy (EGD) performed in either tempera-ture probe cohort.

Feld et al. also raise concerns regarding the introductionof selection bias because EGDs were only performed on pa-tients with a temperature rise ≥39 ◦C. We too raised thisas a limitation of our study in the article. This critique isbased on the belief that the multisensor probe has greatersensitivity; however, that assumes the multisensor probe it-self did not play any role in the development of increasedtemperature rises within the esophagus and potential injury.Our study did not evaluate the sensitivity of the temperatureprobes to detect injury as EGDs were not performed in all pa-tients; therefore, it cannot be assumed the multisensor probeis more sensitive. In our article, we compared the percent-age of esophageal injury in only those with EGDs performedrather than comparing the percentage of injury within the re-spective cohorts as a whole. There is the potential that someinjury was missed; however, it is impossible to know if ahigher percentage of lesions would have been found in thosewithout a temperature rise in the single-sensor group versusthe multisensor group.

We agree with Feld et al. that the multisensor probe isusually enface fluoroscopically rather than in an anteropos-terior configuration. However, we disagree that only an an-teroposterior configuration is necessary to affect the rela-tionship between the esophagus and the left atrium (LA).The multisensor probe is of much greater width (18 mm vs3 mm). The esophagus is mobile and can change configu-ration throughout the procedure, which may be a protectivemechanism.5 We hypothesize that the greater width of themultisensor probe may create a more persistent increase incontact surface area of LA to esophagus. We did not studythe difference in material or design of the probes themselves,as was studied by Deneke et al. with a different catheter

J Cardiovasc Electrophysiol, Vol. 24, p. E25, December 2013.

doi: 10.1111/jce.12304

and temperature probe.6 However, we mention such priorwork in our article to express the potential for a direct in-teraction between a temperature probe and ablation catheter.As mentioned in our “Limitations” section, this was not arandomized controlled trial and there is the potential for con-founding variables that may contribute to the results found.The patients were not matched in our study; however, therewas no significant difference seen between the 2 cohorts inbaseline patient characteristics. We agree with Feld et al.that a randomized controlled trial would be superior, and be-lieve that such study should be performed before using thiscatheter on a wide scale basis. In such a study, not only injuryto the esophagus should be measured, but also the effect ofthe use of this probe on the success rate of the procedure.

BRETT J. CARROLL, M.D.FERNANDO M. CONTRERAS-VALDES, M.D.

EDWIN KEVIN HEIST, M.D., Ph.D.CONOR D. BARRETT, M.D.STEPHAN B. DANIK, M.D.JEREMY N. RUSKIN, M.D.

MOUSSA MANSOUR, M.D.Massachusetts General Hospital,

Boston, Massachusetts, USA

References

1. Feld GK, Tate C, Hsu J: Esophageal temperature monitoring during AFablation: Multi-sensor or single-sensor probe? Letter to the Editor. JCardiovasc Electrophysiol 2013: DOI:10.1111/jce.12305.

2. Carroll BJ, Contreras-Valdes FM, Heist EK, Barrett CD, Danik SB,Ruskin JN, Mansour M: Multi-sensor esophageal temperature probeused during radiofrequency ablation for atrial fibrillation is associatedwith increased intraluminal temperature detection and increased risk ofesophageal injury compared to single-sensor probe. J Cardiovasc Elec-trophysiol 2013;24:958-964.

3. Martinek M, Bencsik G, Aichinger J, Hassanein S, Schoefl R, KuchinkaP, Nesser HJ, Purerfellner H: Esophageal damage during radiofrequencyablation of atrial fibrillation: Impact of energy settings, lesion sets, andesophageal visualization. J Cardiovasc Electrophysiol 2009;20:726-733.

4. Yamasaki H, Tada H, Sekiguchi Y, Igarashi M, Arimoto T, MachinoT, Ozawa M, Naruse Y, Kuroki K, Tsuneoka H, Ito Y, Murakoshi N,Kuga K, Hyodo I, Aonuma K: Prevalence and characteristics of asymp-tomatic excessive transmural injury after radiofrequency catheter ablationof atrial fibrillation. Heart Rhythm 2011;8:826-832.

5. Good E, Oral H, Lemola K, Han J, Tamirisa K, Igic P, Elmouchi D,Tschopp D, Reich S, Chugh A, Bogun F, Pelosi F Jr, Morady F: Move-ment of the esophagus during left atrial catheter ablation for atrial fibril-lation. J Am Coll Cardiol 2005;46:2107-2110.

6. Deneke T, Bunz K, Bastian A, Pasler M, Anders H, Lehmann R, MeuserW, de Groot JR, Horlitz M, Haberkorn R, Mugge A, Shin DI: Utilityof esophageal temperature monitoring during pulmonary vein isolationfor atrial fibrillation using duty-cycled phased radiofrequency ablation.J Cardiovasc Electrophysiol 2011;22:255-261.