Postapproval Study Outcomes of Muscular Ventricular Septal Defect Closure With the Amplatzer Muscular VSD Occluder.

Background: The Amplatzer Muscular Ventricular Septal Defect (VSD) Occluder (Abbott Structural Heart, Plymouth, MN) was approved by the US Food and Drug Administration in 2007. As a condition of approval, a postapproval study was required to further evaluate its safety and effectiveness. This study reports the clinical outcomes from the postapproval study over 5 years of follow-up.

Methods: Patients with complex congenital muscular VSDs at high risk for surgical closure were enrolled between May 2008 and February 2020 in the United States and Canada. The primary effectiveness end points were technical implant success, acute procedure shunt-closure success, and 1-year shunt-closure success. The primary safety end point was the proportion of patients with any serious adverse event within 12 months of the procedure.

Results: A total of 92 patients (median age, 2 years; 50 females) were enrolled in the study. Technical implant success was achieved in 93.8% of patients, and acute shunt-closure success was achieved in 78.0%. Successful shunt closure at 1-year was 94.4% and increased to >98% between 2 and 5 years. Within 12 months of the procedure, all-cause serious adverse events occurred in 47 of the 90 (52.2%) patients which included 7 device-related and 23 procedure-related serious adverse events. Between 1 and 5 years, there was 1 additional device- and procedure-related serious adverse event.

Conclusions: This postapproval study demonstrates that transcatheter muscular VSD closure with the Amplatzer Muscular VSD Occluder is a safe and effective therapy for the treatment of complex congenital muscular VSDs in patients who are at high-risk for surgical closure.

Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00647387.