Severity of Mitral Regurgitation Predicts Risk of Death or Cardiac Transplantation in Children With Idiopathic Dilated Cardiomyopathy

Abstract

Clinical outcomes among children with idiopathic dilated cardiomyopathy (IDC) are diverse, which makes the decision as to when a patient should be listed for a cardiac transplantation challenging. This study aimed to determine echocardiographic and clinical variables that can help clinicians identify those at highest risk for death or cardiac transplantation. The study was a single-center, retrospective chart review of children with IDC. Patients younger than 18 years with a diagnosis of IDC, as defined by a left ventricular end-diastolic dimension (LVEDD) z-score higher than 2, and fractional shortening of less than 28 % on the initial echocardiogram, were included in the study. Echocardiographic parameters including mitral regurgitation (MR) grade and certain clinical parameters at the time of presentation were assessed. A follow-up echocardiogram was similarly studied. The study included 49 children with IDC. Those who died or underwent cardiac transplantation were grouped as "nonsurvivors" (n = 26). The remaining children who either completely recovered or experienced chronic dilated cardiomyopathy were grouped as "survivors" (n = 23). The median age overall was 1.25 years (range 0.1-17 years). The follow-up echocardiograms of the survivors showed significant improvement in left ventricle size, systolic function, left atrial volume, and MR grade, whereas these parameters did not change in the nonsurvivor group. The use of inotropic medications at initial presentation was an independent predictor of death or cardiac transplantation (p < 0.05). The presence of moderate to severe MR at diagnosis also was predictive of a worse outcome.

Assessing Mitral Regurgitation in Patients with Dilated Cardiomyopathy Using 3.0T Cardiac Magnetic Resonance Imaging: Correlation with Morphological and Functional Abnormalities

“…Recognition of the presence and severity of mitral regurgitation, especially a moderate/severe degree of mitral regurgitation, can be of great value for risk stratification, treatment decisions and prognosis prediction (2,3,21). Our studies have revealed that the indexed LVESD, LAESD, and MAA min are positively correlated with increasing grades of mitral regurgitation grading, and in particular, the indexed LVESD is sufficiently sensitive to detect moderate/severe mitral regurgitation.…”

“…In DCM patients, chamber dilatation and alteration in the geometric relationship of the mitral valve apparatus may lead to mitral regurgitation, particularly MAA dilatation. According to previous studies (2,3,21), the presence of mitral regurgitation is associated with a poor outcome, and a moderate/severe degree of mitral regurgitation remains an independent predictor for sudden cardiac death, heart failure, and mortality in DCM patients. Surgical correction for severe mitral regurgitation can improve patients' symptoms and quality of life, reduce hospital mortality, and reveal reverse LV remodeling (14,22).…”

Clinical implications of mitral valve geometric alterations in children with dilated cardiomyopathy

“…Our findings might warrant surgical intervention for secondary mitral regurgitation in the paediatric populations. It is not uncommon for dilated cardiomyopathy patients to develop secondary mitral regurgitation, which results in progressive worsening of left ventricular function and is associated with unfavourable prognosis in children 2,3 as well as adult patients. [17][18][19] Furthermore, mitral repair has been established as an effective therapy leading to reverse left ventricular re-modelling in adult dilated cardiomyopathy patients with secondary mitral regurgitation refractory to medical therapy.…”

“…1 Secondary mitral regurgitation, also known as functional mitral regurgitation, is commonly encountered during echocardiography in children with dilated cardiomyopathy, and secondary mitral regurgitation severity is associated with poor prognosis in paediatric dilated cardiomyopathy patients. 2,3 Surgical intervention for severe secondary mitral regurgitation has been attempted to control heart failure. [4][5][6] Secondary mitral regurgitation is caused by altered mitral valve geometry; left ventricular dilatation leads to increased mitral valve leaflet tethering, which impairs valve closure.…”