a 37-year - old man was admitted to our hospital with long - standing , persistent , lone atrial fibrillation refractory to medical therapy and several attempts of cardioversion .
the patient underwent a total thoracoscopic epicardial ablation without any intraoperative or postoperative complications , followed by a percutaneous postprocedural electrophysiologic evaluation that included confirmation of pulmonary vein isolation and a cavotricuspid isthmus block on the tenth postoperative day .
two weeks after discharge , the patient was admitted to the emergency room with right - sided motor weakness and paresthesia of both upper and lower extremities .
his fever reached 40c , and he had a white blood cell count of 17,690/l .
chest computed tomography imaging revealed a collection of loculated air measuring up to 2 cm in diameter between the right side of the left atrium and the esophagus , with no definitive evidence of a fistulous connection ( fig .
1 ) . brain computed tomography revealed an acute - onset left middle cerebral artery infarction .
an urgent surgical intervention was performed due to our high level of suspicion for a left atrial or pulmonary venous - esophageal fistula .
the chest was opened through the fifth intercostal space via a right posterolateral thoracotomy under one - lung ventilation with a double lumen endotracheal tube .
after anteriorly retracting the lung , a meticulous dissection of the posterior mediastinum between the esophagus , right upper and lower pulmonary veins , and left atrium was performed .
a fistula 2 to 3 mm in diameter was discovered between the right lower pulmonary vein and anterior surface of the esophagus .
surprisingly , there was no bleeding from the fistula on the side of the right lower pulmonary vein .
the right lower pulmonary vein was repaired with a bovine pericardial patch , covered , and fixed with continuous poly - propylene sutures . after repairing the right lower pulmonary vein , we consulted our hospital s thoracic surgeon about repairing the fistula opening on the esophageal side .
he decided to carry out a primary repair of this defect because the defect site was small and relatively clear .
the fistula was carefully debrided and repaired with intermittent 4 - 0 black silk sutures .
the patient s rhythm was converted to sinus rhythm and sustained after cardioversion one day after surgery .
the patient became alert on the third postoperative day , and was extubated on the fifth postoperative day .
he was discharged 39 days postoperatively , with a motor power score of three out of five on the medical research council scale after rehabilitation therapy . on his last outpatient visit ,
two and a half months after surgery , motor power was fully recovered without any sequelae .
a hybrid procedure of a total thoracoscopic epicardial ablation and percutaneous transvenous radiofrequency catheter ablation for lone atrial fibrillation , performed either simultaneously as a single stage procedure or as a two - stage procedure , has been developed to overcome the limitations of each technique and result in better outcomes .
the success rate of this therapy varies according to the specific goals of the intervention and the duration of atrial fibrillation ( paroxysmal or persistent ) .
pison et al .   reported conversion to sinus rhythm after a single stage procedure with a success rate of 83% after one year .
muneretto et al .   reported conversion to sinus rhythm after a two - stage procedure with a success rate of 91.6% at a mean follow - up of 30 months .
after being performed for the first time in south korea at the samsung medical center in february 2012 , we have performed 50 staged hybrid procedures to date with a successful conversion to sinus rhythm in 48 out of 50 patients . unfortunately , we experienced a potentially fatal case of a fistula running from the pulmonary vein to the esophagus fistula despite the high success rate of conversion to sinus rhythm .
we believe our case of a right lower pulmonary venous - esophageal fistula after thoracoscopic epicardial and transvenous catheter ablation to be the first reported in the literature .
even though the radiofrequency catheter ablation was performed after the total thoracoscopic epicardial ablation in a staged procedure , we think that there may have been some degree of infection or edema at the ablation sites due to the short ( ten days ) interval between the components of the hybrid procedure .
the most commonly reported esophageal complication after radiofrequency catheter ablation are left atrial - esophageal fistulas , with an incidence rate of up to 0.2% .
these fistulas result from the usual anatomical relationship of the esophagus to the left atrium and pulmonary veins .
however , unusual variations where the esophagus is situated rightward in the posterior mediastinum near the right pulmonary veins have been described , as in our present case .
. a median sternotomy or a right or left thoracotomy with or without cardiopulmonary bypass is possible depending on the clinical situation and location of the fistula . surgical exposure in our case was achieved via a right posterolateral thoracotomy to expose the suspicious right pulmonary veins and left atrium . in light of this rare but potentially lethal event , we suggest the development of a better - defined consensus , based on further studies , on whether hybrid thoracoscopic epicardial and percutaneous catheter ablations should be performed simultaneously or as a staged procedure .
 a case of a fistula running from the pulmonary vein to the esophagus after a staged hybrid procedure combining total thoracoscopic ablation and percutaneous radiofrequency catheter ablation has not been reported previously . 
 we describe such a case in a 37-year - old man who was successfully treated by surgery . 
CASE REPORT
DISCUSSION