Hybrid VSD Creation or Enlargement

Abstract

The need for ventricular septal defect (VSD) creation or enlargement is a relatively rare one. It usually involves a combination of what appears to be an adequate VSD for flow to the systemic circulation usually in the context of a single ventricle variant (most commonly double outlet right ventricle (DORV)) at birth or at the time of palliative surgery. As the child grows, the VSD becomes restrictive as evidenced by a significant gradient of flow across the VSD, which may be accompanied by depressed ventricular function. Treatment options include surgical or transcatheter creation or enlargement of the VSD. While surgery has been the primary option, it often carries high morbidity and risks [1, 2]. Transcatheter techniques have been developed for this rare anatomic problem. VSD enlargement is relatively straightforward involving the passage of a wire across the existing VSD, balloon septoplasty, and stent implantation. VSD creation is technically more demanding requiring a transseptal puncture across the ventricular septum and in the muscular septum, followed by positioning of a wire, septoplasty, and stent implantation [3, 4]. This technique was first reported in 2006 in a small series of eight patients from Meadows et al. [3]. In that series, five patients underwent VSD creation and three for VSD enlargement. Three of the patients had prior surgical attempts at LV decompression. Gradients across the septum decreased from 76.9 to 20.3 mmHg post intervention. At last follow-up, all stented VSDs were patent although recurrent obstruction was found in the majority of patients due to muscular hypertrophy extending beyond the stent edges. Their conclusion was that in high-risk surgical patients, transcatheter creation or enlargement of VSDs is possible with need for repeat interventions due to recurrent obstruction.