Transcatheter PDA closure: equipment and technique

The Patent Ductus Arteriosus in Adults with Special Focus on Role of CT

The primary imaging modality for the diagnosis of patent ductus arteriosus (PDA) is echocardiography. However, CT may be the technique on which an incidental PDA is first recognized because of the increasing number of chest CT scans performed for a variety of causes. Identification of PDA on CT may lead to earlier closure using a PDA occluder device. Immediate identification of incidental PDA is important, but a high rate of missed diagnosis of PDA has been reported due to its small size and anatomic location. In addition, echocardiography may overlook the presence of even a large PDA due to decrease in the amount of shunting through the PDA caused by high pulmonary artery pressures. This review provides the basic CT anatomy and clinical perspective of PDA, and discusses the role of CT in the evaluation of PDA as well as methods to avoid overlooking a small PDA on CT.

Long-term outcome of coil occlusion in patients with patent ductus arteriosus

BACKGROUND

Coil occlusion has been widely indicated for the closure of patent ductus arteriosus (PDA). Although many reports have shown the efficacy and safety of coil occlusion, the long-term outcome in patients remains controversial. Here, we analyzed the long-term outcome of coil occlusion in patients with PDA in Japan.

METHODS AND RESULTS

We collected the longitudinal data of patients who underwent coil occlusion between 1995 and 2009. A total of 310 coil occlusions were performed in 298 patients with PDA. The median minimum duct diameter was 1.4mm. Successful coil occlusion was achieved in 286 patients (96.0%), and total adverse events were seen in only 28 cases (9.0%). The median follow-up period was 50 months. The occlusion rates at 1 month, 6 months, 1 year, 2 years and 5 years were 90.1%, 94.4%, 97.4%, 97.8% and 97.8%, respectively. Patients with a large PDA (≥4mm) showed a higher rate of residual leakage than those with a small (<2mm) or moderate (2-4mm) PDA (P=0.004). Patients who underwent this procedure in the early study period also showed a higher rate of residual leakage than those in the late study period.

CONCLUSIONS

Coil occlusion is an effective procedure for patients with PDA. Our data indicate that the long-term outcome is promising without any adverse events.

Multicenter USA Amplatzer Patent Ductus Arteriosus Occlusion Device Trial

OBJECTIVES

We sought to review and report initial and one-year efficacy and safety results of the multicenter USA Amplatzer ductal occluder (ADO) device trial.

BACKGROUND

Transcatheter closure of a moderate to large patent ductus arteriosus (PDA) using conventional techniques is challenging. The ADO can close a PDA up to 12 mm in diameter.

METHODS

From September 1999 to June 2002, 484 patients were enrolled in 25 U.S. centers. Forty-five (9%) of 484 patients did not have ADO implantation, because the PDA was too small or because of elevated pulmonary resistance. The median age of the patients at catheterization was 1.8 years (range 0.2 to 70.7 years), and weight was 11 kg (range 4.5 to 164.5 kg).

RESULTS

The median PDA minimal diameter was 2.6 mm (range 0.9 to 11.2 mm); 76 (17%) of 439 were larger than 4.0 mm. Median pulmonary artery mean pressure was 20 mm Hg (range 7 to 80 mm Hg). The ADO was implanted successfully in 435 (99%) of 439 patients, with a median fluoroscopy time of 7.1 min (range 2.9 to 138.4 min). Angiographic demonstration of occlusion was seen in 329 (76%) of 435. This increased to 384 (89%) of 433 on post-catheterization day 1, with occlusion documented in 359 (99.7%) of 360 at one year. At the last evaluation in all patients at any time, PDA closure was documented in 428 (98%) of 435 patients. There have been two cases of partial left pulmonary artery occlusion after ADO implantation and no cases of significant aortic obstruction.

CONCLUSIONS

Moderate to large PDAs can be effectively and safely closed using the ADO device, with excellent initial and one-year results. This device should obviate the need for multiple coils or surgical intervention for these defects.