Incidence of acute thermal esophageal injury after atrial fibrillation ablation guided by prespecified ablation index.

INTRODUCTION: Ablation index (AI), a novel parameter defining energy application at single ablation lesions, calculated by integration of ablation time, energy, catheter stability, and contact force, has been documented to be associated with effective lesions and higher ablation efficacy. Using a prespecified target AI in addition to acute lesion efficacy may affect local collateral damage like esophageal thermal injury when used for guiding radiofrequency (RF) ablation at the posterior left atrial (LA) wall. METHODS AND RESULTS: Consecutive patients undergoing first AF ablations using AI were included. Ablation energy was reduced to 25 W when ablating at posterior LA wall. Two different individually defined AI target values were used (300 and 350 for posterior wall ablation). Esophageal endoscopy (EE) was performed 1 to 3 days after ablation procedure to document and categorize endoscopically detected esophageal thermal lesion (EDEL). Two-hundred and eleven consecutive patients with postprocedural EE were included. Incidence of EDEL was 14% (29 of 211 patients; mild category 1 lesions in 22 of 29 patients (76%) and severe category 2 lesions (ulcers > 5 mm) in 7 of 29 patients (24% of EDEL group, 3% of total group). Ablation time at posterior LA wall (9.5 vs 9.0 minutes [P = .67]) was comparable in patients with and without EDEL. CONCLUSION: LA posterior wall RF ablation adopting AI ≤350 was associated with 14% esophageal thermal injury including 3% of severe esophageal thermal ulcers. This incidence is comparable to historic control groups with non AI-guided AF ablation.

High-Resolution Infrared Thermal Imaging of the Esophagus During Atrial Fibrillation Ablation as a Predictor of Endoscopically Detected Thermal Lesions: Results From the HEAT-AF Study.

BACKGROUND: Endoscopically detected thermal esophageal lesions (EDEL) after ablation of atrial fibrillation may be precursors of atrioesophageal fistula and esophageal luminal temperature monitoring has previously failed to decrease thermal damage. METHODS: Sixty-three patients undergoing their first pulmonary vein isolation using radiofrequency point-by-point catheter ablation were prospectively included in the HEAT-AF study (High-Resolution Esophageal Assessment of Esophageal Temperature During Atrial Fibrillation Ablation) and esophageal temperatures were continuously monitored using a novel infrared thermography system (IRTS). Peak esophageal temperature (Tpeak) was correlated to postablation endoscopy results characterizing patients as EDEL positive or negative. RESULTS: Twelve patients had EDEL (19%). Comparing EDEL positive to negative patients, Tpeak was significantly higher (56.3±4.6°C versus 45.7±5.5°C, P<0.0001). Logistic regression analysis demonstrated Tpeak was a statistically significant predictor ( P=0.0008) of EDEL and yielded an odds ratio of 1.52; 95% CI, (1.24-2.05). Receiver operator curve analysis demonstrated Tpeak as a highly accurate binary classifier with an area under the curve of 93%. CONCLUSIONS: For the first time esophageal temperature monitoring using a high resolution, high-fidelity IRTS allowed accurate prediction of postablation EDEL suggesting that Tpeak alone is an excellent binary classifier of patients at risk of EDEL. The logistic regression model and associated receiver operator curve will aid in the selection of optimal temperature thresholds in future prospective studies.

Progression From Esophageal Thermal Asymptomatic Lesion to Perforation Complicating Atrial Fibrillation Ablation: A Single-Center Registry.

BACKGROUND: Up to 40% of patients demonstrate endoscopically detected asymptomatic esophageal lesions (EDEL) after atrial fibrillation ablation. METHODS AND RESULTS: Patients undergoing first atrial fibrillation ablation and postinterventional esophageal endoscopy were included in the study. Occurrence of esophageal perforating complications during follow-up was related to documented EDEL (category 1: erythema/erosion; category 2: ulcer). In total, 1802 patients underwent first atrial fibrillation ablation procedure between January 2013 and August 2016 at our institution. Out of this group, 832 patients (506 male patients, 61%; 64.0±10.0 years) with symptomatic paroxysmal (n=345; 42%) or persistent atrial fibrillation underwent postprocedural esophageal endoscopy. Patients were ablated using single-tip ablation with conventional or surround flow irrigation and circular ablation catheters with open irrigation (nMARQ). In 295 of 832 patients (35%), a temperature probe was used. EDEL occurred in 150 patients (18%; n=98 category 1 EDEL, n=52 category 2 EDEL). In 5 of 832 patients (0.6%), an esophageal perforation (n=3) or an esophagopericardial or atrioesophageal fistula (n=2) occurred 15 to 28 days (19±6 days) after ablation. Two patients (1 atrioesophageal fistula and 1 esophagopericardial fistula) died. Esophageal perforation occurred only in patients with category 2 lesions (absolute risk, 9.6%). In a logistic regression analysis, ulcers were identified to be a significant predictor for esophageal perforating complications. CONCLUSIONS: Postablation endoscopy seems to identify patients at high risk of esophageal perforating complications only occurring in patients with category 2 EDEL. One out of 10 postablation esophageal ulcers progressed to perforation, and no patient without esophageal thermal ulcers showed the occurrence of perforating esophageal complications.