Background: The design of devices currently used for closure of persistent ductus arteriosus (PDA) with high pulmonary artery pressure is not ideal and there is a risk of embolisation into the aorta.
Objective: To investigate the use of the Amplatzer muscular ventricular septal defect occluder (AMVSDO) for treatment of PDA with high pulmonary artery pressure.
Patients and design: Seven patients, aged 5-12 years, with large PDAs and systemic or near systemic pulmonary artery pressure underwent attempted transcatheter closure using the AMVSDO. The device consists of two low profile disks made of a nitinol wire mesh with a 7 mm connecting waist. Balloon occlusion of the duct was performed before closure from the venous side, and prosthesis size was chosen according to the measured diameter of the occluding balloon. A 7 French sheath was used to deliver the device. All patients underwent a complete haemodynamic and angiographic study one year after occlusion.
Results: The mean (SD) angiographic PDA diameter was 9.8 (1.7) mm (range 7-13 mm) and the mean AMVSDO diameter was 11.4 (1.8) mm (range 9-16 mm). Q(p)/Q(s) ranged from 1.9-2.2 (mean 2.0 (0.1)). Successful device delivery and complete closure occurred in all patients (100% occlusion rate, 95% confidence interval 59.04% to 100.00%). Mean systolic pulmonary artery pressures were as follows: before balloon occlusion, 106 (13) mm Hg; during occlusion, 61 (6) mm Hg; immediately after the procedure, 57 (5) mm Hg; and at the one year follow up catheterisation, 37 (10) mm Hg. Fluoroscopy time was 10.4 (4.3) min (range 7-18 min). No complications occurred.
Conclusions: AMVSDO is an important adjunct for closure of large PDAs associated with high pulmonary artery pressure. Further studies are required to document its efficacy, safety, and long term results in a larger number of patients.