Invited Commentary

Abstract

Mitral regurgitation (MR) accompanying ventricular septal defect (VSD) is uncommon and when present is often presumed to be a result of the physiologic mechanisms of VSD, with left ventricular dilatation that is a consequence of intracardiac shunting. The common expectation is for MR to regress as the ventricle remodels after VSD closure. Indeed, several studies have observed that ventricular volume load and associated MR regress with time after VSD closure alone [1Cho H.J. Ma J.S. Cho Y.K. Ahn B.H. Na K.J. Jeong I.S. Timing in resolution of left heart dilation according to the degree of mitral regurgitation in children with ventricular septal defect after surgical closure.J Pediatr (Rio J). 2014; 90: 71-77Crossref PubMed Scopus (7) Google Scholar, 2Mahadin D.R. Srivastava S. Parness I.A. et al.Outcomes of mitral regurgitation associated with large ventricular septal defect and a normal mitral valve apparatus: does intact atrial septum have an impact?.Pediatr Cardiol. 2011; 32: 1128-1131Crossref PubMed Scopus (9) Google Scholar], or even without VSD closure [3Kleinman C.S. Tabibian M. Starc T.J. Hsu D.T. Gersony W.M. Spontaneous regression of left ventricular dilation in children with restrictive ventricular septal defects.J Pediatr. 2007; 150: 583-586Abstract Full Text Full Text PDF PubMed Scopus (27) Google Scholar]. Indications to intervene for specific types of MR in this setting may lack clear definition. Among 1,898 consecutive VSD closures, Jang and colleagues [4Jang W.S. Kim W.-H. Cho J.Y. et al.Surgical indications and results of mitral valve repair in pediatric patients with ventricular septal defects accompanied by mitral valve regurgitation.Ann Thorac Surg. 2015; 99: 891-898Scopus (6) Google Scholar] found MR in 5.6% of patients, and mitral repairs were judged necessary in half of those with MR. Of the patients who underwent concomitant mitral repair, 35 of 48 patients had prolapse of the anterior mitral valve leaflet, and the remaining patients had annular dilatation alone. At follow-up, all the patients who had VSD closure alone had regression or stability of the degree of MR. Of the patients who underwent repair, MR was also stable or improved, although 2 patients had mild to moderate mitral stenosis. Jang and colleagues demonstrate that, at least in short- to midterm follow-up, annular growth and sustained competence is achievable when posterior annuloplasty and commissuroplasty techniques are used to repair the mitral valve in infancy. Such repair in infancy is not without cost, however, as evidenced by the 2 patients who exhibited mitral stenosis after repair. The history of surgical and catheter-based interventions for cardiac defects is rife with junctures at which we are challenged to separate what we can do from what we should do. It is established that MR from annular dilatation regresses after closure of the VSD and generally does not require valvuloplasty. The fate of MR from structural valve abnormalities in addition to annular enlargement is less clearly defined. Jang and colleagues describe anterior leaflet prolapse as a common structural abnormality among those who underwent valvuloplasty in their series. The prognosis of untreated isolated mitral prolapse in children may be good [5Bisset G.S. Schwartz D.C. Meyer R.A. James F.W. Kaplan S. Clinical spectrum and long-term follow-up of isolated mitral valve prolapse in 119 children.Circulation. 1980; 62: 423-429Crossref PubMed Scopus (88) Google Scholar], but prolapse in the setting of VSD has not undergone specific scrutiny. It would be useful for the authors to leverage their large experience to specifically compare outcomes of treated versus untreated anterior mitral prolapse in the setting of VSD. Surgical Indications and Results of Mitral Valve Repair in Pediatric Patients With Ventricular Septal Defects Accompanied by Mitral Valve RegurgitationThe Annals of Thoracic SurgeryVol. 99Issue 3PreviewVentricular septal defects (VSDs) can be accompanied by mitral regurgitation (MR) owing to chronic volume overload or mitral valve (MV) abnormalities. This study investigates the surgical indications, results, and natural course of pediatric VSD patients with MR. Full-Text PDF