Rotating inotrope therapy in a pediatric population with decompensated heart failure

Contemporary Management of the Failing Fontan

Adult patients with congenital heart disease have now surpassed the pediatric population due to advances in surgery and improved survival. One such complex congenital heart disease seen in adult patients is the Fontan circulation. These patients have complex physiology and are at risk for several complications, including thrombosis of the Fontan pathway, pulmonary vascular disease, heart failure, atrial arrhythmias, atrioventricular valve regurgitation, and protein-losing enteropathy. This review discusses the commonly encountered phenotypes of Fontan circulatory failure and their contemporary management.

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.

Management of circulatory failure after Fontan surgery

With improvement in survival after Fontan surgery resulting in an increasing number of older survivors, there are more patients with a Fontan circulation experiencing circulatory failure each year. Fontan circulatory failure may have a number of underlying etiologies. Once Fontan failure manifests, prognosis is poor, with patient freedom from death or transplant at 10 years of only about 40%. Medical treatments used include traditional heart failure medications such as renin-angiotensin-aldosterone system blockers and beta-blockers, diuretics for symptomatic management, antiarrhythmics for rhythm control, and phosphodiesterase-5 inhibitors to decrease PVR and improve preload. These oral medical therapies are typically not very effective and have little data demonstrating benefit; if there are no surgical or catheter-based interventions to improve the Fontan circulation, patients with severe symptoms often require inotropic medications or mechanical circulatory support. Mechanical circulatory support benefits patients with ventricular dysfunction but may not be as useful in patients with other forms of Fontan failure. Transplant remains the definitive treatment for circulatory failure after Fontan, but patients with a Fontan circulation face many challenges both before and after transplant. There remains significant room and urgent need for improvement in the management and outcomes of patients with circulatory failure after Fontan surgery.

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.

Effect of Preoperative Infusion of Levosimendan on Biomarkers of Myocardial Injury and Haemodynamics After Paediatric Cardiac Surgery: A Randomised Controlled Trial

OBJECTIVE

The aim was to test the hypothesis that preoperative infusion of levosimendan would decrease patients' cardiac biomarker profiles during the immediate postoperative stage (troponin I and B-type natriuretic peptide levels) more efficiently than placebo after cardiopulmonary bypass.

METHODS

In a randomised, placebo-controlled, double-blinded study, 30 paediatric patients were scheduled for congenital heart disease surgery. 15 patients (50%) received prophylactic levosimendan and 15 patients (50%) received placebo from 12 h before cardiopulmonary bypass to 24 h after surgery.

RESULTS

Troponin I levels were higher in the placebo group at 0, 12, and 24 h after cardiopulmonary bypass, although the mean differences between the study groups and the 95% confidence intervals (CIs) for troponin I levels did not present statistically significant differences at any of the three time points considered (mean differences [95% CIs] - 3.32 pg/ml [- 19.34 to 12.70], - 2.42 pg/ml [- 19.78 to 13.95], and - 79.94 pg/ml [- 266.99 to 16.39] at 0, 12, and 24 h, respectively). A similar lack of statistically significant difference was observed for B-type natriuretic peptide (mean differences [95% CIs] 36.86 pg/dl [- 134.16 to 225.64], - 350.79 pg/dl [- 1459.67 to 557.45], and - 310.35 pg/dl [- 1505.76 to 509.82]). Lactic acid levels were significantly lower with levosimendan; the mean differences between the study groups and the 95% CIs for lactate levels present statistically significant differences at 0 h (- 1.52 mmol/l [- 3.19 to - 0.25]) and 12 h (- 1.20 mmol/l [- 2.53 to - 0.10]) after cardiopulmonary bypass. Oxygen delivery (DO2) was significantly higher at 12 h and 24 h after surgery (mean difference [95% CI] 627.70 ml/min/m2 [122.34-1162.67] and 832.35 ml/min/m2 [58.15 to 1651.38], respectively).

CONCLUSIONS

Levosimendan does not significantly improve patients' postoperative troponin I and B-type natriuretic peptide profiles during the immediate postoperative stage in comparison with placebo, although both were numerically higher with placebo. Levosimendan, however, significantly reduced lactic acid levels and improved patients' DO2 profiles. These results highlight the importance of this new drug and its possible benefit with regard to myocardial injury; however, evaluation in larger, adequately powered trials is needed to determine the efficacy of levosimendan. Trial registry number: EudraCT 2012-005310-19.

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.

Recurrent Extubation Failure Following Neonatal Cardiac Surgery Is Associated with Increased Mortality

Extubation failure (EF) following neonatal cardiac surgery is associated with increased mortality. Neonates who experienced EF twice or more (recurrent EF) may have worse outcomes than those who have a single EF or no-EF. The aims of this study are to investigate the in hospital mortality for neonates with recurrent EF compared to those with single or no-EF, and determine factors associated with recurrent EF. Neonates' ≤ 28 days who underwent cardiac surgery from January 2008 to December 2019 were included. EF was defined as unplanned reintubation within 72 h after a planned extubation. 1187 (18 recurrent EF, 84 single EF and 1085 no-EF) neonates were included. Recurrent EF occurred in 18 (17.6%) of 102 neonates undergoing a second extubation. The median time (IQR) to reintubation after the first and second extubations were similar, being 20.9 (3.3-45.2) versus 19.4 (5.5-47) h. The reason for a second-time EF was respiratory in 39% and cardiovascular in 33%. Recurrent EF and single EF was associated with increased mortality (odds ratio, 95% confidence interval (CI) 23.5, 6.9-79.9) and (odds ratio, 95% CI 5.2, 2.3-12.0) compared to no-EF. Based on the final model with risk adjustment, predicted mortality was 29.0% in recurrent EF, 6.5% in single EF, and 1.2% in no-EF. First-time EF due to cardiovascular compromise was associated with recurrent EF (odds ratio, 95% CI 3.1, 1.0-9.7). This study confirmed that patients with recurrent EF have a high morality. Neonates with a cardiovascular reason for first-time EF are more likely to have a recurrent EF than those with other causes.

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.

[Vasopressors and inotropes: use in paediatrics]

The cardiovascular system is a dynamic system, which is required to ensure adequate delivery of oxygen, nutrients, and hormones to the tissues that are necessary for cell metabolism. It also synthesises and modifies the vasoactive components that regulate vascular tone and myocardial function. These vasoactive components have demonstrated their beneficial effects in the management of paediatric patients in a critical condition with heart failure and shock. However, their use and abuse brings harmful effects, increases mortality, and is associated with arrhythmias. An increase in myocardial oxygen consumption favours the presence of ischaemia, therefore it is necessary to know the mechanism of action and indications of these drugs to minimise their harmful effects. The purpose of this review is to describe the pharmacology and clinical applications of inotropic and vasopressor agents in the paediatric patient in acritical condition.

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

BACKGROUND

Limited treatment options are available for children with decompensated dilated cardiomyopathy (DCM), while they wait for either functional recovery or heart transplantation. We evaluated the safety of repetitive levosimendan infusions and short-term and long-term impacts of the therapy in this patient population.

METHODS

Eighty-one repetitive levosimendan infusions administered to 20 patients with DCM at severe or end stage of the disease in the pediatric intensive care unit were analyzed retrospectively. Echocardiographic assessments were reinterpreted by two experienced pediatric cardiologists. The mean follow-up time after therapy was 9.8 ± 3.3 years.

RESULTS

The median age of the patients at the time of the first levosimendan infusion was 1.1 years (interquartile range: 0.3-2.1). Transient hypotension was reported in 17.3% of the infusions. No significant changes in the mean ejection fraction were detected after repetitive levosimendan infusion (31.6 ± 12.5 vs 33.1 ± 12.4; P = .39) or for the laboratory parameters for the group as a whole. In 7 (35%) of 20 patients, the mean ejection fraction improved from 20% ± 12% to 35% ± 11% ( P = .003). The administration of concomitant medications and time may have contributed to the healing process of these patients. Two patients were removed from the transplantation waiting-list owing to clinical recovery after six months of therapy. The long-term survival rate was 70% (n = 14 of 20).

CONCLUSIONS

Repetitive levosimendan infusions in children with DCM appeared to be hemodynamically well tolerated without severe adverse events. Although one-third of the children had a good response to repetitive levosimendan infusions, no overall significant improvement in ventricular performance could be found in this heterogenous DCM patient population, which included the patients in end-stage heart failure.

Pediatric Cardiac Intensive Care Society 2014 Consensus Statement: Pharmacotherapies in Cardiac Critical Care Chronic Heart Failure

OBJECTIVE

Heart failure is a serious complication that can occur in patients with a variety of congenital and acquired disorders including congenital heart disease, cardiomyopathy, and myocarditis. Furthermore, heart failure patients comprise an increasing number of ICU admissions. Thus, it is important for those caring for patients with critical cardiovascular disease to have a thorough understanding of the medications used for the treatment of heart failure. The aim of this review is to provide an overview, rationale, indications, and adverse effects of medications used in the treatment of chronic heart failure.

DATA SOURCES

PubMed, Medline, Cochrane Database of Systemic Reviews.

STUDY SELECTION

Studies were selected on their relevance for pediatric heart failure. When limited data on pediatric heart failure were available, studies in adult patients were selected.

DATA EXTRACTION

Relevant findings from studies were selected by the authors.

DATA SYNTHESIS

The rationale for the efficacy of most heart failure medications used in pediatric patients is extrapolated from studies in adult heart failure. Commonly used medications for chronic heart failure include β-receptor antagonists (e.g., carvedilol and metoprolol), and medications aimed at blocking the renin-angiotensin-aldosterone system (e.g., angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, aldosterone receptor antagonists). In addition, diuretics are useful for symptoms of fluid overload. For patients with impaired perfusion, inotropic agents are useful acutely, but may be associated with worse outcomes when used chronically. Newer medications that have been recently approved in adults (e.g., serelaxin, ivabradine, and neprilysin inhibitor [angiotensin receptor blocker]) may prove to be important in pediatric heart failure.

CONCLUSIONS

Heart failure patients are in an important population of critically ill children. The pharmacologic approach to these patients is aimed at treating symptoms of congestion and/or poor perfusion and improving long-term outcomes.

Heart transplantation in pediatric cardiomyopathies

Cardiomyopathies represent an uncommon but serious cause of heart disease in the pediatric population and can be categorized as dilated, hypertrophic, restrictive and left ventricular non-compaction. Each of these subtypes has multiple potential genetic etiologies in addition to possible non-genetic causes. Many patients with cardiomyopathies can benefit from transplantation, although there is not insignificant morbidity and mortality for those patients. Outcomes both prior to and following transplantation depend on the underlying etiology, the amount of support needed prior to transplantation and the illness severity of the patient prior to transplantation. Mechanical circulatory support is frequently used to bridge patients to transplantation, and newer technologies are currently in development.

The use of levosimendan in children with cancer with severe acute cardiac dysfunction: case series and a review of the literature

We report the use of levosimendan in two febrile, neutropenic children with cancer - one post bone marrow transplant - with acute heart failure following chemotherapy. Initial management with epinephrine, milrinone, and diuresis was unsuccessful. Infusion of levosimendan without a loading dose was added to the ongoing heart failure therapy, which resulted in persistent symptomatic and echocardiographic improvement without major side effects.

Newer inotropes in pediatric heart failure

In the cardiac setting in pediatrics, inotropic support is often employed based on the extrapolation from adult studies, the underlying pathophysiology, pharmacodynamics of inotropes, and anecdotal experience. Large pediatric critical care studies involving inotropic support are rare. Levosimendan, a calcium-sensitizing agent with inotropic and lusitropic properties, is a pyridazole dinitrate derivative with linear pharmacokinetics and a relatively short half life, although an active metabolite, namely, OR-1876, has a half life of 70-80 hours accounting for a prolonged effect. Albeit few, pediatric studies involving levosimendan suggest similar pharmacokinetics to adults with heart failure, an efficacy at least equal to that of milrinone, favorable myocardial oxygen effects, and an ability to decrease concomitant catecholamine dosing. Levosimendan may be a promising new agent in pediatrics, but further experience and study are warranted. Finally, istaroxime, a calcium cycling agent that is in the beginning of adult study, may be another inotrope with lusitropic properties that might be applicable to pediatric patients.