Atrio-oesophageal fistula following circumferential pulmonary vein ablation: verification of diagnosis with multislice computed tomography

A 37-year-old male patient with highly symptomatic and drug refractory paroxysmal atrial fibrillation underwent circumferential pulmonary vein ablation, using the electroanatomic mapping system (CARTO™, Biosense Webster Inc., Diamond Bar, CA, USA) and applying radiofrequency (RF) energy with an irrigated tip catheter (NaviStar™ ThermoCool®, Biosense Webster Inc.). The energy application time was 58.9 min and power was limited to 30 W at the posterior wall, as previously described.1 The patient was the 82nd in a series of 84 patients treated with an unmodified ablation strategy (Figure 1). Twenty-five days after the procedure, the patient presented with fever, later sustained a grand mal seizure and deteriorated into status epilepticus with loss of consciousness on the same day. Suspected atrio-oesophageal fistula was confirmed by multislice spiral computed tomography (CT) scan (Siemens SOMATOM Sensation 16). This showed, in the early phase of iopromide infusion (120 mL at 4 mL/s, Ultravist, Schering, Germany), a breakthrough of contrast medium from the left atrium to the oesophagus with an extensive pneumomediastinum. During preparation for urgent cardiac surgery, the patient died from acute circulatory collapse, most likely due to air embolism. Autopsy demonstrated a fistula of 7 mm diameter from the posterior wall of the left atrium to the oesophagus, just inferior to the right superior pulmonary vein ostium, matching well in size and location with the findings of the CT scan (Figure 2B). In the rare published cases of post-ablation atrio-oesophageal fistula,2–4 a CT scan was performed in three patients, showing pneumomediastinum in all cases, indicating potential oesophageal damage.2,3 The visualization of atrio-oesophageal fistula by cardiac imaging has never been described previously. Anatomic CARTO map of the patient's left atrium in a posteroanterior view showing the circular ablation lesions around the pulmonary vein ostia tagged as red dots. Pulmonary veins are displayed as coloured tubes. (A–C) Cardiac CT scan showing the left atrium (LA) at the level of the right superior pulmonary vein (RSPV) and left superior pulmonary vein (LSPV) in Figure 2A and of the right inferior pulmonary vein (RIPV) in Figure 2C. The interjacent CT slice in Figure 2B verified a fistula (F) from the LA to the oesophagus marked by the gastric tube (Eso). Pneumomediastinum (PM) was detected throughout the retrocardiac space.