Acute pulmonary hemorrhage during atrial fibrillation HotBalloon ablation.

A 64-year-old man with an atrial septal defect was referred for HotBalloon ablation of symptomatic drug-resistant paroxysmal atrial fibrillation. Pulmonary vein (PV) isolation was achieved using a SATAKE HotBalloon ablation system, which was inserted into the left atrium through the deflectable guiding sheath via the atrial septal defect. During ablation of the right superior pulmonary vein carina, the HotBalloon dropped to the left atrium. Hemoptysis and respiratory failure was then observed, and the patient was intubated and controlled under ventilator. The computed tomography identified a pseudoaneurysm developed on the right superior PV, with massive hemorrhagic alveolar flooding.

INTRODUCTION

A radiofrequency HotBalloon catheter has been used to isolate the pulmonary vein (PV) in patients with paroxysmal atrial fibrillation.1 Pulmonary hemorrhage is a rare but serious complication of atrial fibrillation ablation.2 We describe a case in which a patient developed pulmonary hemorrhage during an elective HotBalloon ablation for paroxysmal atrial fibrillation. Written informed consent was obtained from the patient.

CASE REPORT

A 64‐year‐old man with an atrial septal defect was referred for HotBalloon ablation of symptomatic drug‐resistant paroxysmal atrial fibrillation. A 12‐lead electrocardiogram revealed a sinus rhythm with a heart rate of 50 beats per minute and an incomplete right bundle branch block. A chest X‐ray showed mild cardiomegaly with a cardiothoracic ratio of 56% with slight pulmonary congestion. A transthoracic echocardiography confirmed the right atrial and ventricular dilatation, a dilated left atrium of 56 mm, and an atrial septal defect ostium secundum type of 13 × 20 mm with left‐to‐right shunt. The Qp/Qs ratio was 2.4 as calculated by the quantification of shunt flow. We decided to perform pulmonary vein isolation prior to catheter atrial septal defect closer.

Anticoagulation using 5 mg twice daily apixaban was stopped on the procedure day. After femoral vein punctures were performed, a heparin bolus (100 U/kg) was administered and, afterward, a continuous infusion of heparin was provided, maintaining an activated clotting time value between 250 and 350 seconds. Dexmedetomidine was used during procedure. A SATAKE HotBalloon ablation system (Toray Industries, Inc., Tokyo, Japan) was inserted into the left atrium through the deflectable guiding sheath (Treswaltz, Toray Industries, Inc., Tokyo, Japan) via the atrial septal defect. The balloon was placed into the targeted PV ostium and carina by advancing the spring guidewire (SPRING GUIDE WIRE, Toray Medical Co., Ltd., Tokyo, Japan). Balloon positioning in the PV was adjusted by injecting saline to increase the volume.1 Left superior PV ostium, antrum, and carina; left inferior PV antrum; right inferior PV antrum; and right superior PV antrum were ablated in turns. Esophageal temperature was monitored by means of an Esophastar (Japan Lifeline Co., Ltd., Japan) inserted through a nasogastric tube. To prevent injury to the phrenic nerve, the diaphragm was paced by an electrode in the superior vena cava and the compound motor action potential was monitored. Finally, we performed ablation near the carina of the right superior PV with the injection volume of 10 ml and the energy setting of 70 degree Celsius (Figure 1). During radiofrequency energy delivery, the HotBalloon and spring guidewire dropped to the left atrium, immediately stopping energy delivery. Moderate hemoptysis and respiratory failure were then observed, and the patient was intubated and controlled via the ventilator. The computed tomography identified a pseudoaneurysm developed on the right superior PV, with massive hemorrhagic alveolar flooding (Figure 1). The patient required positive pressure ventilation for 2 days and was extubated 2 days after the ablation procedure. Anticoagulation using 5 mg twice daily apixaban was restarted 2 days after the ablation. The patient improved clinically and did not have any additional episodes of hemoptysis. Chest X‐ray performed 3 days after the complication revealed diminution of pulmonary hemorrhage, and the patient discharged 10 days after the complication. The patient underwent re‐ablation of pulmonary vein isolation using radiofrequency catheter 5 months after the first procedure and will undergo catheter closure for ASD if AF recurrence does not occur.

Figure 1

Fluoroscopic view of the radiofrequency HotBalloon catheter and thoracic computed tomography scan. Left panel: Posteroanterior view. The SATAKE HotBalloon is placed at the carina of the right superior pulmonary vein. Right panel: A pseudoaneurysm is represented on the right superior pulmonary vein with massive hemorrhagic alveolar flooding (red arrow). SVC, superior vena cava

DISCUSSION

In this case, pulmonary hemorrhage occurred during HotBalloon ablation targeting the right superior PV. Pulmonary hemorrhage is a rare complication of AF ablation. While there are a few cases where pulmonary hemorrhage occurred immediately after radiofrequency catheter2 or cryoballoon,3 or 2 hours to 1 week after cryoballoon ablation,3, 4 the present case is the first one reported where it occurred during HotBalloon ablation (according to a PubMed search).

Pulmonary hemorrhage may be caused by mechanical trauma from the spring guidewire, which, in our case, dropped down from the superior PV to the left atrium. Although the first 6 cm of spring guidewire is soft, the proximal part is stiff. So, to stabilize the balloon catheter onto the carina of the PV, the proximal part should be placed at the balloon, and the distal (soft) part should be inserted into the periphery of the pulmonary vein. Moreover, as compared with the puncture site of the interatrial septum for patients without atrial septal defect, this patient's atrial septal defect was positioned to the upper and anterior (Figure 2). For these anatomical and structural reasons, it was difficult to stabilize the HotBalloon when placed onto the carina of the right superior PV. If the atrial septal puncture was performed to the ordinary site, the HotBalloon may not have dislodged during ablation of the right superior PV.

Figure 2

Thoracic computed tomography scan and fluoroscopic view of the radiofrequency HotBalloon catheter. Left panel: 3D image of the left atrium and pulmonary veins. Middle panel: Fluoroscopic view of the radiofrequency HotBalloon catheter and illustration of 3D image of the left atrium and pulmonary veins of the patient. Right panel: Fluoroscopic view of the radiofrequency HotBalloon catheter and illustration of 3D image of the left atrium and pulmonary veins from another patient who was performed transseptal puncture via ordinary site. Red circle indicates the atrial septal defect. Blue circle indicates the site where a transseptal puncture is usually done

CONCLUSION

To avoid traumatic complication, it is recommended that the HotBalloon catheter is handled with caution during radiofrequency energy delivery.

CONFLICT OF INTEREST

Authors declare no conflict of interests for this article.