Echocardiographic predictors of mitral stenosis–related death or intervention in infants

BackgroundThe purpose of this study is to identify independent echocardiographic predictors of mitral stenosis (MS)–related death or intervention in infants. Congenital MS is a rare and morphologically heterogeneous lesion with variable prognosis. Among patients diagnosed with MS in early infancy, echocardiographic factors associated with MS-related intervention or death have not been determined.Methods and ResultsThe clinical and echocardiographic data of patients diagnosed with MS at age <6 months by echocardiography between 1986 and 2004 were reviewed. The primary outcome was a composite end point of either mitral valve (MV) intervention (catheter or surgery) or death related to MS. Multiple variables from the initial echocardiogram were analyzed for association with outcomes. Seventy-one patients (median age at diagnosis 63 days) fulfilled the inclusion criteria. Multivariate analysis identified higher initial MV mean inflow gradient (P = .009) and lower left ventricular (LV) diastolic length Z-score (P = .006) at presentation as predictors of intervention or death. Among patients with an initial MV inflow gradient < 2 mm Hg, none reached an end point, whereas, among patients with an initial mean gradient ≥ 5.5 mm Hg, the risk of intervention or death was 85%. Among patients with a gradient > 2 and < 5.5 mm Hg, an end point was reached in 38%, and an LV diastolic length Z-score ≤ 0 was predictive of outcome (71% vs 17%, P = .005). Mitral valve morphology was not predictive of outcome.ConclusionsIn young infants with congenital MS, higher mean MV inflow gradient and shorter LV length, but not MV morphology, are associated with increased risk of MV intervention or MS-related death.