Objective: The purpose of this study was to compare cost and efficacy of surgical closure of patent ductus arteriosus using new critical pathway methods with outpatient transcatheter coil occlusion of patent ductus arteriosus. Methods: Surgical techniques included a transaxillary, muscle- sparing thoracotomy, triple ligation of the patent ductus arteriosus, no chest tube, and discharge from the hospital within 24 hours. Transcatheter coil occlusion of patent ductus arteriosus was done as an outpatient procedure. Costs were compared with inclusion of all hospital and professional charges. Results: From July 1994 until March 1996, 20 patients underwent coil occlusion of patent ductus arteriosus and 20 patients underwent surgical closure of patent ductus arteriosus. Duration of hospitalization was significantly less for the patients receiving coil occlusion (11 ± 6 hours) as compared with that for the patients having surgical ligation (28 ± 7 hours, p < 0.05). Total charges were similar for surgical ligation ($7101 ± $408) as compared with those for coil occlusion ($7104 ± $886, p > 0.05). Morbidity in coil occlusion included inability to occlude the patent ductus arteriosus in two patients (2/20, 10%) and residual patency in two patients (2/18, 11%). Morbidity in the surgical group included nausea and vomiting necessitating hospitalization for more than 36 hours in one patient (1/20, 5%), transient left recurrent laryngeal nerve palsy in one (1/20, 5%), and pneumothorax in two patients (2/20, 10%). There were no instances of residual patency in the surgical group. Conclusions: Transaxillary thoracotomy without tube thoracostomy and with critical pathway methods allows safe and effective ligation of a patent ductus arteriosus with early hospital discharge. This surgical method has similar cost, higher efficacy rate, and applicability in all patients as compared with newer transcatheter coil occlusion techniques for closure of a patent ductus arteriosus.