Atrio-Esophageal Fistula Fatal Complication of Radiofrequency Ablation of Atrial Fibrillation

Abstract

INTRODUCTION: Atrio-esophageal fistula is a fatal complication of radiofrequency ablation, which is associated with 80% mortality rate. Incidence rate for atrio-esophageal fistula formation is reported to be less than 1%. Dissemination of the organisms from the gut into the vasculature is the major cause of mortality. Hence, early diagnosis and immediate surgical intervention is necessary. Here we present a case of atrio-esophageal fistula occurred as a complication of radiofrequency ablation, complicated with sepsis and embolic stroke. CASE PRESENTATION: A 64 year old male with medical history of hypertension, coronary artery disease and chronic atria fibrillation, underwent radiofrequency ablation 10 days back, was admitted to hospital for declining mental status and fever for 5 days. No other systemic symptoms were reported. Exam was significant for 101 degree centigrade temperature, irregular heart rate in 140's. Patient was obtunded, with left gaze preference without any response to pain stimulus. Diagnostic examination was significant for troponin level 60.70 ng/ml. Electrocardiogram showed atria fibrillation, heart rate in 140's, no acute ST segment changes or Q waves. Echocardiogram showed ejection fraction of 55% and global hypo kinesis. Broad spectrum antibiotics were administered for possible sepsis. High troponin level without ST segment change, and recent ablation procedure raised the suspicion for atrio-esophageal fistula. CTA Chest revealed 9 - 10 mm wide ulceration of left atrium posterior wall communicating with distal esophagus at T7 level. CT Head showed multiple non specific cerebral lesions in left and right occipital and left frontal-parietal regions. Patient underwent emergent right thoracotomy, and Left atria repair, along with esophageal stent placement. Blood cultures were positive for Enterococci. DISCUSSION: CT Chest with IV contrast is the best diagnostic modality which may reveal multiple findings, not limited to contrast presence in esophagus or mediastenum but may also show pneumo mediastenum, intra-atria air, posterior left atria wall thickening. Procedures like Trans-esophageal echocardiography and esophagoscopy result in air embolism. High radiofrequency pulses delivered to the mid-portion of posterior wall of left atrium where there is disproportionate and less fatty layer, predispose the development of atrio-esophageal fistula. Procedural measures like left atrium posterior wall monitoring by the use of intra-cardiac echocardiography, use of esophageal temperature probe, moving the lines to the roof or decreasing the radiofrequency power while ablating the posterior wall of LA were studied with a reasonable success to avoid injury. CONCLUSIONS: Given the associated poor prognosis, prompt recognition and emergent intervention are mandatory to decrease the mortality.