Long-Term Outcomes of Dilated Cardiomyopathy Diagnosed During Childhood

Abstract

Epidemiological studies from the National Australian Childhood Cardiomyopathy Study (NACCS) and the North American Pediatric Cardiomyopathy Registry (PCMR) determined the incidence of newly diagnosed DCM to be between 0.57 cases per 100 000 population per year for children 0 to 18 years of age 5 and 0.73 cases per 100 000 population per year for ages 0 to 10 years of age. 1 In particular, the registries demonstrated a higher incidence in infants and Australian indigenous and black populations. 5,6 In these studies, freedom from death or transplantation was between 69% and 72% at 1 year and 54% and 63% at 5 years after diagnosis. 5,6 In the Background-Existing studies of childhood dilated cardiomyopathy deal mainly with early survival. This population-based study examines long-term outcomes for children with dilated cardiomyopathy. Methods and Results-The diagnosis of dilated cardiomyopathy was based on clinical, echocardiographic, and pathological findings. The primary study end point included time to the combined outcome of death or cardiac transplantation. There were 175 patients 0 to <10 years of age at the time of diagnosis. Survival free from death or transplantation was 74% (95% confidence interval, 67-80) 1 year after diagnosis, 62% (95% confidence interval, 55-69) at 10 years, and 56% (95% confidence interval, 46-65) at 20 years. In multivariable analysis, age at diagnosis <4 weeks or >5 years, familial cardiomyopathy, and lower baseline left ventricular fractional shortening Z score were associated with increased risk of death or transplantation, as was lower left ventricular fractional shortening Z score during follow-up. At 15 years after diagnosis, echocardiographic normalization had occurred in 69% of surviving study subjects. Normalization was related to higher baseline left ventricular fractional shortening Z score, higher left ventricular fractional shortening Z score during follow-up, and greater improvement in left ventricular fractional shortening Z score. Children with lymphocytic myocarditis had better survival and a higher rate of echocardiographic normalization. At the latest follow-up, 100 of 104 of survivors (96%) were free of cardiac symptoms, and 83 (80%) were no longer receiving pharmacotherapy. Although population-based registries have provided valuable insights into the incidence, risk factors, and short-term outcomes of DCM, late survival and the symptomatic status for children with DCM remain uncertain. Better information about long-term outcomes would facilitate decisions about medical care, including the role of cardiac transplantation. The present study examines late outcomes for children with DCM enrolled in NACCS. Conclusions-Death MethodsNACCS is a population-based cohort study of all children in Australia diagnosed with primary cardiomyopathy at 0 to 10 years of age between January 1, 1987, and December 31, 1996. Local institutional review board approval was obtained from participating centers. The methodology and epidemiological findings of NACCS have been described previ...

The highest mortality rates in childhood dilated cardiomyopathy occur during the first year after diagnosis

“…In the American Paediatric Cardiomyopathy Registry, children with neuromuscular disease seemed to have higher mortality rates, mainly due to a lower rate of transplants 19. Some authors have suggested that older children, over the age of five years, may have a lower rate of transplant‐free survival 17, and it has also been suggested that the rate of recovery is higher in younger children 19, 20, 21.…”

“…This finding was in agreement with the study by Alexander et al. 20, who reported familiar or genetic cardiomyopathy in 27% of children with DCM. Other studies have suggested that this can occur up to 50% of all cases 17, 25.…”

Heart failure from heart muscle disease in childhood: a 5–10 year follow‐up study in the UK and Ireland

“…Since our original study, follow‐up of patient cohorts from the Australian Childhood Cardiomyopathy Study and the American Pediatric Cardiomyopathy Registry have now provided valuable data about longer‐term outcomes for specific diagnostic groups 6, 7. This UK and Ireland National cohort differs in that it was selected to look at outcomes of symptomatic new‐onset heart failure in children, rather than cardiomyopathy per se .…”

“…Results from the Australian Cardiomyopathy in Childhood Study showed that outcome for familial cases of dilated cardiomyopathy was worse than non‐familial cases, but other studies have shown no difference between these two groups 6, 11…”

“…They are also consistent with and enhance the data from cardiomyopathy series, despite the fact that this patient cohort was selected on the basis of clinically significant heart failure, rather than a diagnosis of cardiomyopathy per se . There is a broad and expanding consensus that there is a better outcome with younger age at presentation, excepting those under 4 weeks of age, who were identified as a separate group with a worse outcome in the Australian dilated cardiomyopathy study 6, 9, 14, 15. A variety of echocardiographic parameters have been used in different studies as predictors of recovery, including left ventricular end diastolic dimensions, left ventricular fractional shortening or ejection fraction measurements and septal peak systolic tissue Doppler velocities.…”