DISCUSSION
The incidence of residual defect after surgical repair of closure of residual leak after surgery post-MI VSR is noted to be around 10–40% (6). Transcatheter closure as a bail- out or salvage where redo surgery weighs more risk than benefit may provide an attractive and less invasive therapeutic strategy for residual defects (7), contraindications being defect size >35 mm, basal VSR near mitral or aortic valves, and apical VSD without sufficient margins.
This catheter-based procedure can be accomplished using different devices, some of them not specifically designed for this purpose. To date, the majority of studies of transcatheter closure of post-infarction VSR have reported on the use of Amplatzer muscular VSD occluder and recently on the Amplatzer postinfarction muscular VSD device (PIMVSD) (Abbott Vascular, Santa Clara, CA, USA) (8-13). The Amplatzer PIMVSD device is a nitinol construct available in larger sizes than the Amplatzer muscular VSD device (maximum waist diameter, 24 mm versus 18 mm, respectively) with a longer connecting waist (10 mm versus 7 mm) and therefore more suited to larger and complex VSRs. Nevertheless, sometimes there’s the need to implant additional devices with a substantial increase in procedural risks.
A primary transcatheter closure of an acute anterior post-infarction VSD closure has been performed few years ago in an 85-year old female using for the first time the custom-made Occlutech® PIVSD occluder with a successful outcome (14).
The Occlutech® PIVSD occluder is a newly designed device with several advanced features compared to previously existing technology: unique braiding technology, no distal hub, soft and atraumatic flexible oval-shaped discs, special surface treatment reducing the risk of thrombosis. The main advantages of this innovative device in comparison with the Amplatzer post MI occluder are (Supplemental Video): first, a wider range of waist sizes (from 16 mm to 36 mm) with bigger left-sided oval disc and a much greater overlap to be able to catch more substantial healthy myocardium and allow a larger surface area between the ventricular septum and the left-sided disc of the device; second, the 10-mm slit-like elliptical connecting waist has no radial strength to prevent tearing the borders of the patch dehiscence; third, due to its conformability, a waist size of the occluder 8 mm or even 10 mm larger than the rupture size may be used without undermining the margins of the repaired area.
Polyester fabric sutured into both discs and into the inside of the waist requires time to thrombose and endothelialize before being efficient in preventing shunt across the high transventricular pressure gradient. Further minor device modifications such as a denser fabric and covering on the distal left ventricle disc to completely seal off the shunt (“closure at implant”) may be hopefully awaited as well as a dedicated braided and less deformable delivery sheath in order to avoid its kinking.