The efficacy of mitral valve surgery in children with dilated cardiomyopathy and severe mitral regurgitation

Long-Term Outcomes and Prognosticators of Pediatric Primary Dilated Cardiomyopathy in an Asian Cohort

Background: Dilated cardiomyopathy (DCM) is the most common childhood cardiomyopathy. The epidemiological profiles and prognosticators of clinical outcomes in Asian populations are not well elucidated. Methods: Data of 104 children aged <18 years with a diagnosis of primary DCM from January 1990 to December 2019 in our institutional database were retrospectively investigated. Relevant demographic, echocardiographic, and clinical variables were recorded for analysis. A P <0.05 was considered statistically significant. Results: The median age at diagnosis was 1.4 years (interquartile range = 0.3-9.1 years), and 52.9% were males. During a median follow-up duration of 4.8 years, 48 patients (46.2%) were placed on the transplantation waitlist, and 52.1% of them eventually received heart transplants. An exceptionally high overall waitlist mortality rate was noted (27.1%), which was even higher (43.5%) if the diagnostic age was <3 years. The 1-, 5-, and 10-year transplant-free were 61.1, 48.0, and 42.8%. Age at diagnosis >3 years and severe mitral regurgitation at initial diagnosis were independent risk factors for death or transplantation (hazard ratios = 2.93 and 3.31, respectively; for both, P <0.001). In total, 11 patients (10.6%) experienced ventricular function recovery after a median follow-up of 2.5 (interquartile range = 1.65-5) years. Younger age at diagnosis was associated a higher probability of ventricular function recovery. Conclusions: Despite donor shortage for heart transplantation and subsequently high waitlist mortality, our data from an Asian cohort indicated that transplant-free long-term survival was comparable with that noted in reports from Western populations. Although younger patients had exceptionally higher waitlist mortality, lower diagnostic age was associated with better long-term survival and higher likelihood of ventricular function recovery.

Longitudinal Prediction of Transplant-Free Survival by Echocardiography in Pediatric Dilated Cardiomyopathy

BACKGROUND

The prognostic significance of serial echocardiography and its rate of change in children with dilated cardiomyopathy (DCM) is incompletely defined.

METHODS

We retrospectively analysed up to 4 serial echocardiograms. Associations between mortality/transplant and echocardiographic parameters over time and between outcomes and the rate of change of echocardiographic parameters were analysed. Estimation of patient-specific intercepts and slopes was done using linear regression models.

RESULTS

Fifty-seven DCM children were studied (50% male; median age, 0.6 year; average follow-up, 2.1 ± 2.4 years). The median time to transplant or death was 2.0 years. Increased left ventricular (LV) diastolic (LVEDD) and systolic (LVESD) dimensions and myocardial performance index (MPI) were associated with increased mortality and transplant risk. Increased LV ejection fraction, mitral E-deceleration time, right ventricular (RV) fractional area change, and tricuspid annular plane systolic excursion were associated with reduced mortality and transplant risk. Transplant/mortality likelihood increased by 41.6% and 19.8% for each unit increase in LVEDD and LVESD z scores, respectively (LVEDD: hazard ratio [HR], 1.416; 95% confidence interval [CI], 1.285-1.560; P < 0.001; LVESD: HR, 1.198; 95% CI, 1.147-1.251; P < 0.001). A higher monthly change in LVESD z score increased transplant/mortality likelihood by 85.6% (HR, 1.856; 95% CI, 1.572-2.191; P = 0.015). Greater changes in mitral E/e' (HR, 0.707; 95% CI, 0.636-0.786; P < 0.001) and RV MPI (HR, 0.412; 95% CI, 0.277-0.613; P < 0.001) were associated with reduced mortality and transplant risk.

CONCLUSIONS

LV and RV systolic and diastolic dimensions and function over time and their rate of change are associated with risk for transplant and mortality in childhood DCM. Serial changes in these parameters may be useful to predict clinical outcomes.

Mitral valve replacement in dilated cardiomyopathy: A valid option?

Background

Dilated cardiomyopathy (DCM) is characterized by left ventricular dilation and dysfunction. The association with significant mitral regurgitation worsens the prognosis.

Case report

A 2-year-old girl presented with DCM and severe mitral regurgitation. She had a history of viral myocarditis at the age of 4 months, necessitating recurrent hospital admissions for management of intractable heart failure, pneumonia, and failure to thrive. The decision was taken to proceed for mitral valve surgery, which ended with mitral valve replacement. Over 3 years of follow-up after surgery, there was significant improvement in her weight gain and she improved clinically. There were still recurrent admissions, but mostly for adjustment of her deranged anticoagulation medications.

Conclusion

Mitral valve surgery might be indicated in selected patients with DCM.

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

We aimed to elucidate the relationship between severity of secondary mitral regurgitation and mitral valve geometry in children with dilated cardiomyopathy. The medical records of 16 children with dilated cardiomyopathy (median age, 1.2 years; range, 0.4-12.3 years) were reviewed. Mitral valve geometry was evaluated by measuring coaptation depth using echocardiographic apical four-chamber views at the initial presentation. Patients were dichotomised according to the mitral regurgitation severity: patients with moderate or severe secondary mitral regurgitation (n=6) and those with mild secondary mitral regurgitation (n=10). A total of 58 healthy children were considered as normal controls, and a regression equation to predict coaptation depth by body surface area was derived: coaptation depth [mm]=4.37+1.34×ln (body surface area [m2]) (residual standard error, 0.49; adjusted R2, 0.68; p<0.0001). Compared with patients with mild secondary mitral regurgitation, those with moderate or severe secondary mitral regurgitation had significantly larger coaptation depth z-scores (6.4±2.3 versus 1.9±1.4, p<0.005), larger mitral annulus diameter z-scores (3.6±2.6 versus 0.9±1.8, p<0.05), higher left ventricular sphericity index (0.89±0.07 versus 0.79±0.06, p<0.005), and greater left ventricular fraction shortening (0.15±0.05 versus 0.09±0.05, p<0.05). In conclusion, geometric alteration in the mitral valve and the left ventricle is associated with the severity of secondary mitral regurgitation in paediatric dilated cardiomyopathy, which would provide a theoretical background to surgical intervention for secondary mitral regurgitation in paediatric populations.

Mitral valve surgery for severe mitral regurgitation and dilated cardiomyopathy--a bridge to transplant: case report and a review of literature

We report a child with myocardial necrosis, dilated cardiomyopathy, and severe mitral valve (MV) regurgitation following neonatal enteroviral myocarditis. He underwent MV annuloplasty at 18 months and MV replacement at 3 years of age. He remains asymptomatic on medical therapy at 8 years of age. Mitral valve surgery may stabilize the evolution of dilated cardiomyopathy and delay the ultimate need for heart transplant.

Usefulness of mitral regurgitation as a marker of increased risk for death or cardiac transplantation in idiopathic dilated cardiomyopathy in children

In adults with idiopathic dilated cardiomyopathy (IDC), mitral regurgitation (MR) is associated with adverse prognosis and is often addressed by surgery or intervention. MR is commonly found in children with IDC, but its prognostic relevance has not been defined, and interventions to reduce MR are not routinely performed in this population. In this study, it was hypothesized that MR is an independent risk factor for death or transplantation. This was a single-center, retrospective study of sequential patients with IDC or familial IDC (left ventricular end-diastolic dimension z score >2 and ejection fraction <50%). Patients with acute myocarditis or previous mitral surgery were excluded. MR severity was graded according to American Society of Echocardiography guidelines as mild, moderate, or severe on the basis of MR jet vena contracta width. Left ventricular end-diastolic volume, end-systolic volume, and ejection fraction were measured by biplane Simpson's method. Forty-two children with IDC were studied. The mean follow-up period was 25 months. At initial assessment, 34 children (82%) were taking angiotensin-converting enzyme inhibitors, 25 (60%) furosemide, 27 (65%) β blockers, and 7 (17%) intravenous inotropes. The mean indexed end-systolic volume was 91 ± 51 ml/m(2). The mean ejection fraction was 27 ± 16%. MR was mild in 42%, moderate in 19%, severe in 2%, and absent in 35% of patients. MR severity progressed from initial to last evaluation. MR severity was an independent risk factor for lower freedom from death or transplantation. Progression in MR severity increased the annual hazard of death or transplantation by a factor of 2.4 (p = 0.003). In conclusion, MR severity is independently associated with worse clinical status and decreased freedom from death or transplantation in children with IDC.

Current management of pediatric dilated cardiomyopathy

PURPOSE OF REVIEW

American and European guidelines for treatment of adult heart failure have been recently revised. This review will reconcile those guidelines to recent studies and experience in the treatment of pediatric dilated cardiomyopathy.

RECENT FINDINGS

Therapy for pediatric dilated cardiomyopathy includes establishing a diagnosis for diagnostic-specific therapies as well as preventive strategies for anthracycline toxicity and muscular dystrophy. Pediatric studies demonstrate safety and efficacy for use of angiotensin-converting enzyme inhibition and beta-blockers in dilated cardiomyopathy. Cardiac resynchronization and mitral annuloplasty represent potential nonpharmacologic therapies. Implantable defibrillator therapy may be of less import in children as compared with adults. Ventricular assist devices (VADs) are now available for all ages, which can improve survival and potentially can lead to recovery.

SUMMARY

The robust development of new therapies for adult heart failure has been successfully applied to children with dilated cardiomyopathy. Therapies for severe, intractable heart failure have been more widely utilized than therapies for mild-to-moderate heart failure.

[Update on pediatric cardiology and congenital heart disease]

The fields of pediatric cardiology and congenital heart disease have experienced considerable progress in the last few years, with advances in new diagnostic and therapeutic techniques that can be applied at all stages of life from the fetus to the adult. This article reviews scientific publications in a number of areas that appeared between August 2007 and September 2008. In developed countries, congenital heart disease is becoming increasingly prevalent in nonpediatric patients, including pregnant women. Actions aimed at preventing coronary heart disease must be started early in infancy and should involve the promotion of a healthy diet and lifestyle. Recent developments in echocardiography include the introduction of three-dimensional echocardiography and of new techniques such as two-dimensional speckle tracking imaging, which can be used for both anatomical and functional investigations in patients with complex heart disease, including a univentricular heart. Progress has also occurred in fetal cardiology, with new data on prognosis and prognostic factors and developments in intrauterine interventions, though indications for these interventions have still to be established. Heart transplantation has become a routine procedure, supplemented in some cases by circulatory support devices. In catheter interventions, new devices have become available for the closure of atrial or ventricular septal defects and patent ductus arteriosus as well as for percutaneous pulmonary valve implantation. Surgery is also advancing, in some cases with hybrid techniques, particularly for the treatment of hypoplastic left heart syndrome. The article ends with a review of publications on cardiomyopathy, myocarditis and the treatment of bacterial endocarditis.