Early Experiences Using Cocoon Occluders for Closure of a Ventricular Septal Defect

Transcatheter device closure of ventricular septal defect (VSD) has become an attractive alternative to surgery. We report here on our early experiences of transcatheter closure of VSD using Cocoon devices, which are now available in Korea.

We reviewed the medical records and angiographic images of 13 patients who underwent transcatheter closure of VSD with a Cocoon occluder at Samsung Medical Center. The median patient age was 5.8 years, and the median patient weight was 20.3 kg.

The device was successfully implanted in all patients. The follow-up period was 10 ± 6 months, and no mortality was observed. An immediate residual leak on the next day was detected in 7 patients (including 4 with perimembranous VSD). However, 6 months later, a residual leak was observed only in 2 patients with perimembranous VSD and 1 patient with muscular VSD. Early conduction abnormalities were observed in 3 patients, all of whom had perimembranous VSD, but no significant complete atrioventricular block was observed. One patient experienced newly developed significant aortic regurgitation that decreased spontaneously but still existed at the 6 month follow-up. No hemolysis or embolization was noted on the next day or during the follow-up period.

Cocoon devices can be used safely and effectively for VSD closure. However, residual leaks and conduction abnormalities may occur early after implantation, especially in patients with perimembranous VSD. Although normal conduction was recovered, long-term evaluation remains essential.