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nous VSDs has been well described [4, 5] . Percutaneous approaches to conal septal VSDs have proven more challenging given the inherent deficiencies of adequate septal tissue below the aortic or pulmonary valve coupled with the risk of semilunar valve disruption by most double disk devices made for muscular VSDs. Still not all conal septal VSDs are created equal, with some being more amenable to percutaneous approaches at closure. As such, prior interventional papers have further categorized conal septal VSDs based on the anatomic feasibility of interventional closure as: (1) subpulmonary VSDs have a muscular rim <2 mm below the pulmonary annulus (i.e., are not suitable for a percutaneous approach), and (2) intracristal VSDs have a muscular rim ≥ 2 mm below the pulmonary annulus (i.e., may be suitable for a percutaneous approach with asymmetric disc devices) [6] . In the latest issue of Cardiology , Dr. Cui and colleagues report the largest published case series involving the closure of intracristal VSDs with the O eccentric shape VSD occluder (Shanghai Shape Memory Alloy Co. Ltd; SHSMA) [7] . Various SHSMA occluders have been described previously for closing select atrial septal defects and patent ductus arteriosus in addition to prior smaller reports for intracristal VSDs [6, 8, 9] . This device was specifically designed to be asymmetric, with a smaller disc on Ventricular septal defects (VSDs) are among the most common cardiac defects, present in approximately 50% of all patients with congenital heart disease, with an estimated prevalence in the population of about 0.3 per 1,000 live births [1] . VSDs are classically categorized by the precise anatomic location of the defect involving the membranous, inlet, muscular, or outlet septum in addition to the physiologic relationship between ventricles (restrictive vs. nonrestrictive). Conal septal VSDs involve a deficiency in the outlet or infundibulum septum; the nomenclature for these defects is redundant and often confusing, using terms such as supracristal, conoventricular, outlet, doubly committed subarterial, juxta-arterial, and subpulmonary. Conal septal VSDs imply an absence of fibrous continuity between the aortic and pulmonary valves, and can lead to prolapsing of the right coronary cusp of the aortic valve and significant aortic valve disruption over time. As such, there is a lower threshold for recommending surgical VSD closure at an early age for these types of VSD [2] . In 1987, Locke and colleagues performed the first percutaneous VSD closures using the Rashkind double umbrella device, which interestingly was originally developed to treat patent ductus arteriosus [3] . Subsequently, percutaneous closure for muscular and select membraReceived: April 18, 2017 Accepted: April 18, 2017 Published online: May 13, 2017