Invited Commentary

Abstract

In this issue of The Annals, Song and colleagues [1Song S. Fan T. Li B. et al.Minimally invasive peratrial device closure of perimembranous ventricular septal defect through a right infraaxillary route: clinical experience and preliminary results.Ann Thorac Surg. 2017; 103: 199-205Abstract Full Text Full Text PDF PubMed Scopus (12) Google Scholar] report a novel minimally invasive peratrial device closure of perimembranous VSD via a right infraaxillary route. They report successful closure of perimembranous ventricular septal defect (VSD) in 97.9% of patients with no evident valve regurgitation, no complete AV block and no device dislocation. The most impressive aspect of this technique is the avoidance of cardiopulmonary bypass. The fact that transesophageal echocardiography provides the imaging for guidance and maneuvering means that the incision can be kept small. Since being one of the first operations to be performed in the open-heart era, VSD closure remains at the core of congenital cardiac surgical practice, whether it is isolated or it exists as a part of complex congenital cardiac defect. Surgical closure of VSD has been the gold standard for decades, being associated with low morbidity and mortality [2Maile S. Kadner A. Turina M.I. Prêtre R. Detachment of the anterior leaflet of the tricuspid valve to expose perimembranous ventricular septal defects.Ann Thorac Surg. 2003; 75: 944-946Abstract Full Text Full Text PDF PubMed Scopus (26) Google Scholar]. Hence, any possible alternative technique must prove its equivalence or superiority to the existing gold standard. The development of percutaneous transcatheter device closure of VSD in the last decade has definitely added another perspective to the available armamentarium for VSD closure [3Yang L. Tai B.C. Khin L.W. Quek S.C. A systematic review on the efficacy and safety of transcatheter device closure of ventricular septal defects (VSD).J Interv Cardiol. 2014; 27: 260-272Crossref PubMed Scopus (59) Google Scholar]. While surgical and transcatheter closure have niche indications, the presented technique pushes the limits by fusing the advantages of surgical direct access with the device closure which fundamentally serve to avoid cardiopulmonary bypass. This technique also cashes in on the shortcoming of transcatheter approach, which is limited by the vascular access needed to perform the same in infancy. Different techniques of transthoracic device closure of perimembranous VSD without cardiopulmonary bypass (through an inferior sternotomy or parasternal approach) have been described, but these approaches are cosmetically less attractive [4Xing Q. Pan S. An Q. et al.Minimally invasive perventricular device closure of perimembranous ventricular septal defect without cardiopulmonary bypass: multicenter experience and mid-term follow-up.J Thoracic Cardiovasc Surg. 2010; 139: 1409-1415Abstract Full Text Full Text PDF PubMed Scopus (72) Google Scholar, 5Hongxin L. Zhang N. Wenbin G. et al.Peratrial device closure of perimembranous ventricular septal defects through a right parasternal approach.Ann Thorac Surg. 2014; 98: 668-674Abstract Full Text Full Text PDF PubMed Scopus (23) Google Scholar]. The major inclusion criteria described in this paper, including age of 6 months and older, right-sided opening of 3 to 8 mm, and sub-aortic rim of more than 1 mm, clearly define the limits of this approach. For the whole series, the median age was 2.1 years and median body weight was 12 kg, meaning that the majority of children were older than the patient population presenting in the Western world. However, considering that they have used this approach in children as young as 6 months, it is not farfetched to think that theoretically many of the perimembranous VSDs (with an adequate aortic rim) could eventually be approached with this technique. As far as the efficacy of closure, development of tricuspid regurgitation, aortic regurgitation and right bundle branch block are concerned, the authors claim equivalence to the conventional surgical results. However, the mean follow-up of 10 months (maximum follow-up 2 years) is not long enough to be able to draw definite conclusions about the late risks of complete AV block, structural degeneration, and the mechanism of remodeling of the outlet septum with the growth of the child. These aspects must be critically followed up. With more than a decade of experience with the transcatheter device closure of congenital VSD, it has been determined that the incidence of late AV block occurring because of scar formation and compression of the posteroinferior rim can be significant [6Forbes T.J. The race to close perimembranous ventricular septal defects (PVSD): Proceed with caution.J Interven Cardiol. 2014; 27: 273-274Crossref PubMed Scopus (2) Google Scholar]. Similarly, it can be speculated that the distance of the device disc from the aortic valve may remain constant despite growth of the child; whether these have any consequences for the aortic valve or on the hemorheology (hemolysis) need to be followed up. Considering that the procedural and short-term results of this procedure are equivalent, this basic question needs to be answered: Why change? The prospect of being able to avoid cardiopulmonary bypass is definitely welcome. The long-term questions about the integrity of the device, rhythm and valve related problems are yet to be answered comprehensively. Importantly, to date published reports stem from a select couple of centers. It remains to be proven that these results are reproducible at other leading centers. For sure, this evolving concept may open doors for further innovation toward absorbable devices where the ingrowing autologous tissue may provide a lasting solution without potential long-term complications. To summarize, the concept remains appealing, but the present data call for seeking satisfactory answers to the pending questions before it is ready for a step forward. Minimally Invasive Peratrial Device Closure of Perimembranous Ventricular Septal Defect Through a Right Infraaxillary Route: Clinical Experience and Preliminary ResultsThe Annals of Thoracic SurgeryVol. 103Issue 1PreviewBoth percutaneous and perventricular device closures of perimembranous ventricular septal defects (PmVSD) present certain drawbacks. We report our experiences with a new, minimally invasive surgery using a peratrial device closure of PmVSD through a right infraaxillary route. Full-Text PDF