Pediatric dilated cardiomyopathy is the most common type of cardiomyopathy in children and accounts for the most heart transplantations in pediatric patients. Despite the progressive nature of the disorder and high mortality and morbidity rates, few studies aimed to investigate the etiology and treatments of children affected by dilated cardiomyopathy. Treatments for children are mainly adopted from studies aimed at adults without testing their effectiveness in pediatrics. Several studies were undertaken in recent years to learn whether adult-oriented evidence-based treatments for dilated cardiomyopathy are applicable to children.
Background
Dilated cardiomyopathy is the most common form of cardiomyopathy in children. The disorder is characterized by an increased size of the left ventricular chamber. Consequently, the affected child experiences reduced contractility and systolic dysfunction (Somarriba, Extein, & Miller, 2008). The causes of dilated cardiomyopathy were identified in only 34 percent of pediatric cases, and they mainly include myocarditis and neuromuscular disorders with a few cases of inborn errors resulting in metabolic and malformation syndromes (Somarriba et al., 2008).
Population and Topic Significance
There are four types of cardiomyopathy, but dilated cardiomyopathy has the highest prevalence among children with an annual incidence between 0.34 and 0.73 per 100,000 patients (Alvarez, Wilkinson, & Lipshultz, 2007). Although cases of dilated cardiomyopathy in children rarely occur, it accounts for 76 percent of all heart transplants in pediatric patients (Alexander et al., 2013). It has high morbidity and mortality rates because the most effective treatment for improving survival rate is heart transplantation.
The area of pediatric cardiomyopathy deserves more research than is currently available. The causes of any type of cardiomyopathy in 57 to 68 percent of children are unknown, which makes the diagnosis difficult (Somarriba et al., 2008). The progression of the disorder is also much faster in children than in adults, and few studies investigated evidence-based practices in pediatric dilated cardiomyopathy, so there have been no recorded improvements in survival rates in contrast to previous studies (Kantor, Abraham, Dipchand, Benson, & Redington, 2010).
Although dilated cardiomyopathy can affect people at any age, newborn children and children between the ages of 1 and 12 are at a significant risk. A study by Alexander et al. (2013) found that 74 percent of children survive one year after the diagnosis without a transplant and 56 percent of them survive 15 years after the diagnosis without a transplant.
Various studies conducted on adult patients with dilated cardiomyopathy are currently being adjusted and adopted for the purpose of treating children with dilated cardiomyopathy and improving their quality of life. For example, Kantor et al. (2010) compared medication treatment results in children to the existing body of research aimed at adults. While those studies are important contributions to developing evidence-based practices for managing dilated cardiomyopathy in the pediatric population, more research is required to understand the etiology of pediatric dilated cardiomyopathy and develop evidence-based treatments.
Literature Review: Current Evidence-Based Treatments
The most effective treatment for pediatric dilated cardiomyopathy-induced heart failure is heart transplantation. Recent studies reported survival rates of 92 percent at five years after transplant and 53 percent at 15 years after transplant in pediatric dilated cardiomyopathy patients (Morales et al., 2007). The limitations of heart transplantation include lack of suitable donors, organ rejection, and the necessity for chronic immunosuppressant medication, but it is the only survival option for patients who do not respond to pharmacotherapy and show signs of rapid disease progression.
Pharmacotherapy for pediatric dilated cardiomyopathy has shifted from the traditional interventions involving digoxin and diuretics toward angiotensin-converting enzyme inhibitors (ACEIs) and beta-adrenergic receptor blockers (BBs). According to Kantor et al. (2010), there have been no significant changes in survival rates when pediatric patients are treated with ACEI and BB instead of digoxin and diuretics. Nevertheless, pharmacological maintenance therapy is critical for survival because patient without maintenance treatments die or require transplantation sooner than patients who receive medicine (Kantor et al., 2010).
As alternative interventions for improving the quality of life in pediatric patients, studies started investigating the effects of exercise programs and surgical interventions for children that have already been proven in adults. An evaluation of the study by Somarriba et al. (2008) and the study by de Lima Lopes, Meneguim, Soares Muniz, and da Silva Herbas Palomo (2011) will determine the necessity and implications of their findings and the limitations of those studies.
Study Evaluations
Study 1: Exercise for Managing Pediatric Dilated Cardiomyopathy
The study by Somarriba et al. (2008) is a case study that presents an exercise program intervention for children with cardiomyopathy. The aim of the study was to evaluate the application of physical exercise programs in children with cardiomyopathy. Even with improvements in heart transplant interventions, heart transplants required by many cardiomyopathy patients do not contribute to improving the quality of life in affected children (Somarriba et al., 2008).
Therefore, ancillary therapies need to be studied because of their potential to improve the quality of life. Exercise is one of the most important ancillary therapies because most children with cardiomyopathy will remain inactive. However, their sedentary lifestyle may result in secondary disorders, which is why evaluating the safety and effectiveness of exercise in children with chronic heart conditions is an important disease management topic.
Two patient case studies were presented. Both patients were seven years of age with idiopathic dilated cardiomyopathy, and both had to adhere to a stable dose of medication over the past three months or more to satisfy the inclusion criteria. One patient was male and the other one female. The exact disease state was not reported, but patients with a New York Hear Association Class IV heart condition were excluded from the intervention.
Intervention. A 12-week program consisting of anaerobic and flexibility training with aerobic components was implemented twice per week. The aim of the study was to assess the safety of the program and determine whether its completion is a realistic goal for children with cardiomyopathy.
Measurements. Anthropometry measures included height, weight, body mass index (BMI), skin-fold thickness, and dual X-ray absorptiomentry scanning. The overall cardiovascular and left ventricular functions were measured with echocardiography and flow-mediated vasodilation. Aerobic function was assessed with exercise stress testing. Strength was assessed with 1-repetition maximum tests. The quality of life was measured with Functional Status Questionnaire (FSQ) and the Child Health Questionnaire (CHQ). The FSQ tool has high validity and reliability levels, but the choice for CHQ is questionable because it has adequate internal reliability at best. The measures were taken once at baseline and once after the intervention to determine how exercise affected their cardiac function, strength, and quality of life.
Limitations. Because of the study design involving individual cases, the researchers cannot generalize their conclusions to the rest of the population, which is a significant limitation to the study. Another critical limitation is the use of CHQ for assessing quality of life because of the low internal consistency and discriminative validity. Finally, the choice of resistance training as the first-line intervention is questionable because anaerobic exercises without a functional aerobic metabolism may worsen acute stages, which suggests implementing aerobic exercise programs before anaerobic programs may be a safer and more effective alternative.
Practical implications. Although changes in cardiac functions were insignificant, the exercise program was not hazardous to cardiac health. However, the participants’ BMI, body fat, strength, flexibility, and quality of life improved, which means exercise can be a safe and effective intervention for improving quality of life in children with cardiomyopathy.
In clinical settings, multidisciplinary teams would be required to carry out the exercise intervention in the pediatric population, and Somarriba et al. (2008) recommend a team including exercise physiologists, dietitians, registered nurses, nurse practitioners, and social workers as the optimal staffing strategy. While exercise physiologists and dietitians would prescribe intervention programs, the nurses would be responsible for monitoring the patients’ measurements and cardiac output to assess potential risks and benefits of the intervention. Although nurses should ideally intervene if cases of acute stages of pediatric dilated cardiomyopathy occur, the entire staff needs to be trained to perform interventions such as mechanical ventilation and endotracheal entubation to improve patient safety.
Further research. The intervention used by Somarriba et al. (2008) could be further improved by implementing aerobic exercise programs before transitioning into resistance training. Although recovery from anaerobic training strengthens aerobic functions, acute engagement in physical activity for individuals who are leading a sedentary lifestyle and have low aerobic functions may worsen their disease. Another study aimed at evaluating aerobic exercise interventions is required. It is expected that strengthening aerobic functions before focusing on strength and flexibility training will improve cardiac functions more significantly than the results reported by Somarriba et al. (2008) if the same measurement strategies are used.
Study 2: Nursing Interventions for Children with Intra-aortic Balloon Pump Support
The aim of the study by de Lima Lopes et al. (2011) aimed to identify nursing diagnoses and interventions applicable to children with dilated cardiomyopathy who require an intra-aortic balloon pump. The case study presented a case of one 7-year-old male child diagnosed with both dilated cardiomyopathy and heart failure. Within a year of the diagnosis, the patient’s fatigue, palpitations, and vomiting worsened. Before the heart transplant was performed, the patient’s hemodynamic levels decreased and an intra-aortic balloon pump was instilled.
The application and consequences of intra-aortic balloon pump instillations in adults are known much better than they are in children because the intervention is rarely used in children (de Lima Lopes et al., 2011). Therefore, studying adequate nursing interventions for children undergoing intra-aortic balloon pump instillations is required to establish evidence-based practices that can be used by nurses in clinical settings.
Intervention and measurements. Three cardiology and pediatric nurses familiar with Nursing Intervention Classification taxonomies NANDA-International taxonomies developed nursing diagnoses and intervention for a child after an intra-aortic balloon pump instillation. The measurements taken were vital signs and laboratory tests. The measurements were used to determine potential risks and develop nursing diagnosis and interventions based on established and proven classification systems.
Limitations. As a case study, this study cannot generalize any conclusions, but that limitation is something that is difficult to overcome in researching pediatric dilated cardiomyopathy. Because it is a rare occurrence with high mortality and morbidity rate, acquiring a sample size large enough to conduct a proper randomized controlled trial is nearly impossible. Therefore, a case study is an appropriate choice of study design given the small chances for acquiring large intervention and control groups.
The study was not quantitative, which means it cannot be repeated by other researchers. In addition, the potential risks and nursing diagnoses were only identified, but have not been evaluated individually. The only conclusion that can be drawn from the study is that care for children with an intra-aortic balloon pump is a complex condition that requires a collaborative nursing team effort to manage.
Practical implications. The study by de Lima Lopes et al. (2011) emphasizes the importance of standardized classifications of nursing diagnoses and interventions. The study found that decreased cardiac output was the most significant risk, but it also identified the necessity for interventions regarding risks for infection, aspiration, constipation, renal perfusion, bleeding, and excessive fluid volume. With an outlined care program, collaborative interventions are more organized and effective in practice.
Further research. The study found that most risks, such as renal perfusion, constipation, and aspiration, were probably the consequences of decreased cardiac output. Therefore, an extension study should focus on how managing decreased cardiac output affects other risks identified by de Lima Lopes et al. (2011). A nursing intervention for shock management and circulatory care with mechanical assist devices should be used, and the outcomes measured would include cardiac output, as well as associated risks, including renal perfusion, constipation, and aspiration. It is expected that managing cardiac output would have a beneficial impact on those associated risks in addition to managing cardiac output.
Summary and Conclusion
Despite the progress in heart transplants for pediatric dilated cardiomyopathy, survival rates in the event-free population remain the same. The majority of causes of pediatric dilated cardiomyopathy remain unknown, and pharmacotherapy did not improve over the past decades, even though it shows better survival rates than non-pharmacological interventions. When the amount of research for pediatric dilated cardiomyopathy is compared to the amount of research on pediatric dilated cardiomyopathy in adults, it is clear that further research is needed to adapt many findings to children and establish evidence-based practices. The studies evaluated present important efforts towards expanding the knowledge of managing pediatric dilated cardiomyopathy and improving the patients’ quality of life, but suggested improvements should be taken in account to optimize those interventions.
References
Alexander, P. M., Daubeney, P. E., Nugent, A. W., Lee, K. J., Turner, C., Colan, S. D., & Weintraub, R. G. (2013). Long-term outcomes of dilated cardiomyopathy diagnosed during childhood: Results from a national population-based study of childhood cardiomyopathy. Circulation, 128(18), 2039-2046.
Alvarez, J. A., Wilkinson, J. D., & Lipshultz, S. E. (2007). Outcome predictors for pediatric dilated cardiomyopathy: A systematic review. Progress in Pediatric Cardiology, 23(1), 25-32.
de Lima Lopes, J., Meneguim, S., Soares Muniz, C. C., & da Silva Herbas Palomo, J. (2011). Special report: Nursing diagnoses and interventions for a child with dilated cardiomyopathy requiring intra‐aortic balloon pump support – Case report. International Journal of Nursing Terminologies and Classifications, 22(1), 23-32.
Kantor, P. F., Abraham, J. R., Dipchand, A. I., Benson, L. N., & Redington, A. N. (2010). The impact of changing medical therapy on transplantation-free survival in pediatric dilated cardiomyopathy. Journal of the American College of Cardiology, 55(13), 1377-1384.
Morales, D. L., Dreyer, W. J., Denfield, S. W., Heinle, J. S., McKenzie, E. D., Graves, D. E., & Fraser Jr, C. D. (2007). Over two decades of pediatric heart transplantation: How has survival changed? The Journal of Thoracic and Cardiovascular Surgery, 133(3), 632-639.
Somarriba, G., Extein, J., & Miller, T. L. (2008). Exercise rehabilitation in pediatric cardiomyopathy. Progress in Pediatric Cardiology, 25(1), 91-102.
