Volume 12, Issue 4 , Pages 250-256, Winter 2007
Thoracoscopic Approach to Patent Ductus Arteriosus
Article Outline
Current options for the treatment of a patent ductus arteriosus include open division or ligation via left thoracotomy or sternotomy, transcatheter device occlusion, and ligation via video-assisted thoracoscopic surgery (VATS). Open division has almost 50 years of use and represents the “gold standard.” Direct visualization and control of the ductus minimize risk, and ductal division avoids possible residual patency. However, the advent of transcatheter device closure motivated surgeons to refine their approach. To decrease the trauma of surgery, incision length was reduced, and muscle-sparing incisions came into vogue. Despite these refinements, the necessity of rib retraction remained, and postthoracotomy pain and scoliosis remained significant long-term complications.
As endoscopic techniques gained favor in adult general and thoracic surgery, VATS for congenital heart operations also became a consideration. In the VATS approach, pleural access is gained via small thoracostomies; visualization is achieved with a video camera, and dissection is performed with endoscopic instruments. This approach enables the ductus to be closed with a minimum of trauma to the chest wall. Conversion to an open thoracotomy is the fallback option during each procedure.
Endoscopic ductal closure, like open closure, can be successfully undertaken in patients of any size, as well as in patients in a tenuous hemodynamic state. In a premature neonate, the overall incision length may not be less than with an open procedure. However, rib retraction, with its potential long-term effects on the chest wall, are avoided. Premature neonates who are not on an oscillating ventilator are transferred to the operating room for endoscopic ductus interruption. Those requiring an oscillating ventilator undergo open duct interruption in the neonatal intensive care unit. Other contraindications to the endoscopic approach include a calcified ductus, ductal diameter greater than 1 cm, and dense pleural adhesions due to infection, or prior surgery. The following figures illustrate the operative approach.
Operative Technique
Figure 1.
General anesthesia is established with a single-lumen endotracheal tube. VATS ductal ligation is performed with the patient in a right lateral decubitus position. A transesophageal echocardiographic probe is placed, and the anatomy is confirmed.
Figure 2.
Four thoracotomy incisions are made with a No. 15 blade. Blunt dissection with a curved hemostat allows entry into the pleural space, and four trocars are placed to allow instrument insertion. The most anterior port admits a 2-mm grasping forceps, the next port an expanding lung retractor, and the next a videoscope (4-mm, 30-degree face angle for infants; 2.7-mm, 30-degree angle for premature neonates). The posterior port admits the cautery, scissors, and clip applier. The camera is advanced as the anesthesiologist limits ventilation to allow the lung to fall away from the chest wall. A cotton swab placed through the posterior trocar further pushes the lung away from the chest wall to create a space for the lung retractor.
Figure 3.
The lung retractor is opened under direct vision via the videoscope, and the left upper lobe is retracted medially and inferiorly. Using the left subclavian artery as a landmark for the origin of the ductus, the scope is advanced further into the chest. L = left; LPA = left pulmonary artery; LSCA = left subclavian artery; N = nerve; PDA = patent ductus arteriosus.
Figure 4.
A left-handed grasper and right-handed cautery are used to elevate a parietal pleural flap over the ductus. The left vagus and recurrent laryngeal nerves are easily seen. Tissue is grasped and lifted away from the aorta before the cautery is activated. L = left; N = nerve.
Figure 5.
The pleural flap is raised up to the takeoff of the left subclavian artery. Lymphatics at the upper end of the pleural dissection are carefully sealed with the cautery. LSCA = left subclavian artery.
Figure 6.
The crossing vein is divided if it obscures exposure. The lower aspect of the ductus is dissected with blunt and cautery dissection, taking care to avoid the recurrent laryngeal nerve. The upper angle of the ductus is opened with sharp dissection to create a plane between the ductus and aortic arch. Dissection is then continued with blunt spreading. Once the upper and lower angles of the ductus are free, the duct is sized by comparison to a juxtaposed cotton swab. PDA = patent ductus ateriosus.
Figure 7.
The appropriate-sized clip applier is advanced through the posterior trocar, using the grasper to clear first the lower, then the upper angle. The clip applier should fall easily into place. If resistance is felt, the back wall of the ductus should be further separated from the underlying esophagus with blunt dissection. The clip is tightened around the ductus, and ductal closure is confirmed by transesophageal echocardiography. Patency of the left pulmonary artery and aorta are also ensured. The pleural edges are cauterized to avoid a chylous leak. The instruments are removed, with care being taken to avoid scissoring the lung when closing the retractor. A 12-F thoracostomy tube is placed via the retractor port, and the incisions are closed with subcuticular absorbable sutures. The thoracostomy tube is removed in the operating room. PDA = patent ductus ateriosus.
Figure 8.
To convert to an open procedure, the thoracotomy incisions are joined, and the pleural space is entered through the fourth interspace. Malleable retractors are used for exposure. Pleural retraction sutures are used to expose the ductus. Proximal and distal sutures secured to the adventitia are placed around the ductus. Once these are tied down, the ductus may be left in continuity, or divided.
Premature neonates are returned to the neonatal intensive care unit intubated. Elective patients are awakened and extubated in the operating room. They advance to a regular diet and activity by the evening and are ready for hospital discharge the next morning. A chest film is obtained before discharge, to detect pneumothorax or chylothorax. A follow-up echocardiogram is obtained at 1 month to ensure ductal closure.
Note: Material in this article was adapted from the chapter Burke RP: Patent ductus arteriosus, in Kaiser LR, Kron IL, Spray TL (eds): Mastery of Cardiothoracic Surgery. Philadelphia, PA, Lippincott, Williams & Wilkins, 2007, pp 716-721.
PII: S1522-2942(07)00126-2
doi:10.1053/j.optechstcvs.2007.11.002
© 2007 Elsevier Inc. All rights reserved.
Volume 12, Issue 4 , Pages 250-256, Winter 2007
