The Hemodynamic Effects and Safety of Repetitive Levosimendan Infusions on Children With Dilated Cardiomyopathy

Familial dilated cardiomyopathy in a child: a case report

BACKGROUND

Dilated cardiomyopathy (DCM) commonly leads to heart failure (HF) and represents the most common indication for cardiac transplantation in the pediatric population. Clinical manifestations of DCM are mainly the symptoms of heart failure; it is diagnosed by EKG, chest x-ray and echocardiography. For the idiopathic and familial diseases cases of DCM, there are no definite guidelines for treatment in children as they are treated for prognostic improvement.

CASE PRESENTATION

We report the case of a 2-year-old girl diagnosed with dilated cardiomyopathy associated with homozygous mutation in the Myosin Light Chain 3 gene admitted for edema in lower extremities, muscle weakness, lethargy and vomiting, and she was found to be in cardiogenic shock. Chest x-ray showed cardiomegaly and EKG showed first degree atrioventricular block. Echocardiogram showed severe biventricular systolic and diastolic dysfunction. After 70 days of hospitalization, the patient went into cardiac arrest with cessation of electrical and mechanical activity of the heart, despite cardiopulmonary resuscitative efforts.

CONCLUSION

Although rare, pediatric DCM carries a high risk of morbidity and mortality and a lack of curative therapy.

Safety of Levosimendan in Pediatric Patients: An Up-to-Date Systematic Review

BACKGROUND

The potential risks associated with the use of levosimendan in the pediatric population has not been systematically evaluated. This study aimed to review the available evidence regarding the safety of this treatment.

METHODS

Bio Med Central, PubMed, Embase, and the Cochrane Central Register of clinical trials were searched for studies describing levosimendan administration in the pediatric population in any setting. Relevant studies were independently screened, selected, and their data extracted by two investigators. The authors excluded: reviews, meta-analyses, as well as basic research and trials involving patients >18 years old. The primary outcome was the number and the type of adverse side effects reported during levosimendan administration.

RESULTS

The updated systematic review included 48 studies, enrolling a total of 1,271 pediatric patients who received levosimendan as treatment (790 patients in the 11 studies that reported side effects). The primary adverse effects of levosimendan administration were hypotension and cardiac arrhythmias, particularly tachycardia. Hypotension occurred in approximately 28.9% of patients, while arrhythmia occurred in about 12.3% of patients. Meta analysis of RCTs revealed a rate of all-cause mortality of 2.0% (8 out of 385) in the levosimendan group compared to 3.9% (15 out of 378) in the control group (dobutamine, milrinone or placebo) (risk ratio [RR] = 0.55; 95% confidence interval [CI] = 0.25-1.21; P = 0.14; I2 = 0%) CONCLUSIONS: Hypotension and cardiac arrhythmia are the most reported side effects of levosimendan in pediatric patients. However, adverse events remain underreported, especially in randomized trials.

Thin filament cardiomyopathies: A review of genetics, disease mechanisms, and emerging therapeutics

All muscle contraction occurs due to the cyclical interaction between sarcomeric thin and thick filament proteins within the myocyte. The thin filament consists of the proteins actin, tropomyosin, Troponin C, Troponin I, and Troponin T. Mutations in these proteins can result in various forms of cardiomyopathy, including hypertrophic, restrictive, and dilated phenotypes and account for as many as 30% of all cases of inherited cardiomyopathy. There is significant evidence that thin filament mutations contribute to dysregulation of Ca2+ within the sarcomere and may have a distinct pathomechanism of disease from cardiomyopathy associated with thick filament mutations. A number of distinct clinical findings appear to be correlated with thin-filament mutations: greater degrees of restrictive cardiomyopathy and relatively less left ventricular (LV) hypertrophy and LV outflow tract obstruction than that seen with thick filament mutations, increased morbidity associated with heart failure, increased arrhythmia burden and potentially higher mortality. Most therapies that improve outcomes in heart failure blunt the neurohormonal pathways involved in cardiac remodeling, while most therapies for hypertrophic cardiomyopathy involve use of negative inotropes to reduce LV hypertrophy or septal reduction therapies to reduce LV outflow tract obstruction. None of these therapies directly address the underlying sarcomeric dysfunction associated with thin-filament mutations. With mounting evidence that thin filament cardiomyopathies occur through a distinct mechanism, there is need for therapies targeting the unique, underlying mechanisms tailored for each patient depending on a given mutation.

Drug Treatment of Heart Failure in Children: Gaps and Opportunities

Medical therapy for pediatric heart failure is based on a detailed mechanistic understanding of the underlying causes, which are diverse and unlike those encountered in most adult patients. Diuresis and improved perfusion are the immediate goals of care in the child with acute decompensated heart failure. Conversion to maintenance oral therapy for heart failure is based on the results of landmark studies in adults, as well as recent pediatric clinical trials and heart failure guidelines. There will continue to be an important role for newer drugs, some of which are in active trials in adults, and some of which are already approved for use in children. The need to plan for clinical trials in children during drug development for heart failure is emphasized.

Effect of Levosimendan Treatment in Pediatric Patients With Cardiac Dysfunction: An Update of a Systematic Review and Meta-Analysis of Randomized Controlled Trials

Levosimendan increasingly has been used to treat heart failure and cardiac dysfunction in pediatric patients. Currently, there is only limited evidence that this drug positively affects outcomes. The authors' aim was to investigate the effects of levosimendan on hemodynamic parameters and outcomes in pediatric patients in all clinical settings. The study design was a systematic review of randomized and nonrandomized studies. Randomized clinical trials (RCTs) were included in a meta-analysis. The primary outcome of the meta-analysis was the effect of levosimendan on central venous oxygen saturation (ScvO₂) and lactate values as surrogate markers of low-cardiac-output syndrome. The study setting was any acute care setting. Study participants were pediatric patients (age <18 years) receiving levosimendan, and the intervention was levosimendan versus any control treatment. The authors identified 44 studies published from 2004 to 2020, including a total of 1,131 pediatric patients. Nine studies (enrolling 547 patients) were RCTs, all performed in a pediatric cardiac surgery setting. Three RCTs were judged to carry a low risk of bias. In the RCTs, levosimendan administration was associated with a significant improvement of ScvO₂ (p = 0.03) and a trend toward lower postoperative lactate levels (p = 0.08). No differences could be found for secondary outcomes. Levosimendan use in pediatric patients is not associated with major side effects and may lead to hemodynamic improvement after cardiac surgery. However, its impact on major clinical outcomes remains to be determined. Overall, the quality of evidence for levosimendan use in pediatric patients is low, and further high-quality RCTs are needed.

Recent and Upcoming Drug Therapies for Pediatric Heart Failure

Pediatric heart failure (HF) is an important clinical condition with high morbidity, mortality, and costs. Due to the heterogeneity in clinical presentation and etiologies, the development of therapeutic strategies is more challenging in children than adults. Most guidelines recommending drug therapy for pediatric HF are extrapolated from studies in adults. Unfortunately, even using all available treatment, progression to cardiac transplantation is common. The development of prospective clinical trials in the pediatric population has significant obstacles, including small sample sizes, slow recruitment rates, challenging endpoints, and high costs. However, progress is being made as evidenced by the recent introduction of ivabradine and of sacubitril/valsartan. In the last 5 years, new drugs have also been developed for HF with reduced ejection fraction (HFrEF) in adults. The use of well-designed prospective clinical trials will be fundamental in the evaluation of safety and efficacy of these new drugs on the pediatric population. The aim of this article is to review the clinical presentation and management of acute and chronic pediatric heart failure, focusing on systolic dysfunction in patients with biventricular circulation and a systemic left ventricle. We discuss the drugs recently approved for children and those emerging, or in use for adults with HFrEF.

Ambulatory Intravenous Inotropic Support and or Levosimendan in Pediatric and Congenital Heart Failure: Safety, Survival, Improvement, or Transplantation

End-stage heart failure (HF) frequently needs continuous inotropic support in hospital and has high morbidity and mortality in absence of heart transplantation. This study reports outcome, efficacy, and safety of continuous ambulatory inotropes (AI) and/or periodic levosimendan (LS) infusions in pediatric HF patients. The study included 27 patients, median age 9.4 (0.1-26.1) years, with severe HF (6 myocarditis, 13 dilated cardiomyopathy, 2 restrictive cardiomyopathy, 6 repaired congenital heart disease). Dobutamine and milrinone AI were administered in 21 patients through a permanent central catheter for median duration 1.0 (0.3-3.7) years. Additionally, 14 AI patients and the remaining 6 study patients received periodic LS infusions for median duration 1.1 (0.2-4.2) years. During median follow-up 2.1 (0.3-21.3) years, 4 patients died of worsening HF after 0.8-2.1 years AI, 6 patients underwent heart transplantation with only 3 survivors, while the rest remained stable out of the hospital with complications 4 line infections treated with antibiotics and 4 catheter reinsertions due to dislodgement. Severe pulmonary hypertension was reversed with AI in 2 patients, allowing successful heart-only transplantation. Therapy with AI was discontinued after 1.4-0.4 years in 6 improved myocarditis and 3 cardiomyopathy patients without deterioration. In conclusion, prolonged AI and/or LS infusions in HF are safe and beneficial even in small infants, allowing stabilization and reasonable social and family life out of the hospital. It may provide precious time for heart transplantation or myocardial remodeling, improvement, and possible discontinuation even after long periods of support.

Hemodynamic support of a 15-year-old waiting for a heart transplant: Is there a role for levosimendan in pediatric heart failure?

Decompensated heart failure in children requires rapid and aggressive support. In refractory cases, invasive supportive care is essential to ensure cardiac output. This results in lengthy pediatric intensive care unit (PICU) stays, secondary morbidity, and high cost. Levosimendan may help palliate the pitfalls encountered with the usual treatment. It has been shown to improve hemodynamics and decrease morbidity and mortality from heart failure in adult trials and pediatric cohorts. We report the case of a 15-year-old boy with dilated cardiomyopathy and refractory ventricular dysfunction who was weaned from continuous inotropes and discharged from the PICU with levosimendan while waiting for heart transplantation.