Treatment of cardiac failure in infancy and childhood

Pharmacological Heart Failure Therapy in Children: Focus on Inotropic Support

Pediatric heart failure is a clinical syndrome, which needs to be distinctly defined and the pathophysiological consequences considered. Pharmacological treatment depends on the disease- and age-specific myocardial characteristics. Acute and chronic low cardiac output is the result of an inadequate heart rate (rhythm), myocardial contractility, preload and afterload, and also ventriculo-ventricular interaction, synchrony, atrio-ventricular and ventricular-arterial coupling. The treatment of choice is curing the cause of heart failure, if possible.Acute HF therapy is still based to the use of catecholamines and inodilators. The cornerstone of chronic HF treatment consists of blocking the endogenous, neuro-humoral axis, in particular the adrenergic and renin-angiotensin-aldosterone system.Before neprilysin inhibitors are used in young children, their potential side-effect for inducing Alzheimer disease needs to be clarified. The focus of the current review is put on the differential use of the inotropic drugs as epinephrine, norepinephrine, dopamine and dobutamine, and also the inodilators milrinone and levosimendan. Considering effects and side-effects of any cardiac stimulating treatment strategy, co-medication with ß-blockers, angiotensin converting inhibitors (ACEIs), angiotensin blockers (ARBs) and mineralocorticoid receptor antagonists (MRAs) is not a contradiction, but a senseful measure, even still during the acute inotropic treatment.Missing sophisticated clinical trials using accurate entry criteria and clinically relevant endpoints, there is especially in cardiovascular diagnosis and treatment of young children a compromise of evidence-based versus pathophysiology-based procedures. But based on the pharmacological and pathophysiological knowledge a hypothesis-driven individualized treatment is already currently possible and therefore indicated.

Pediatric heart failure therapy: why β1-receptor blocker, tissue ACE-I and mineralocorticoid-receptor-blocker?

Pediatric heart failure (HF) treatment lagged behind the knowledge of pharmacological research and evidence-based clinical experience in adults. Considering the lack of prospective, double blind randomized studies in children, the review is focused on the preferred indication of specific β1-adrenoreceptor blockers (ARB), mineralocorticoid antagonists and tissue angiotensin-converting enzyme inhibitors (ACE-I). Our recommendations are based on the specificity in children, the effectiveness and the side-effect profile of HF-drugs, the receptor-physiological knowledge and the negative results of the few pediatric HF studies with an "evidence study label". In the interest of our pediatric patients, effective HF treatment has not longer to be postponed by balancing between evidence-based versus pathophysiology-based approach. At our institution, bisoprolol, lisinopril and spironolactone (BLS) are used treating HF in patients with left-right shunt lesions, reduced ejection fraction as well as during the inter-stage after HLHS-Hybrid approach. Chronic use of diuretics and fluid restriction is avoided, if always possible; intravascular volume deficiency stimulates further the neurohumoral axis. Pediatric HF needs to be treated with a strategy respecting the variable pathophysiology and the differences of receptor physiology between children and adult patients. The personalized treatment can be easily proofed by the surrogate parameters as heart rate, breath pattern, weight gain and image-derived parameters as well as biomarkers. Effective HF-therapy is also the basis for novel regenerative strategies in particular for young children with "end-stage" HF avoiding cardiac transplant or death.

Effects of digoxin on systolic time intervals of neonates and infants

Systolic time intervals were measured in 27 normal newborn infants before and after administration of oral digoxin (30 µg/kg). Systolic intervals were also measured in 10 newborns and infants with congestive heart failure before and after this same 30 µg/kg dose of digoxin, but also after administration of a much larger "digitalizing dose" of 80 µg/kg. Preejection period (PEP) shortened significantly in the normal newborns following the smaller dose. Changes in ejection time (ET) were much less striking and appeared to be transient, lasting less than 8 hours. When small doses of digoxin were given to the babies with congestive failure, PEP again shortened significantly. In general, the larger doses of digoxin produced no further changes in PEP or ET, although there were individual exceptions. The demonstration that maximal inotropic effect, as measured by PEP changes, usually occurred with small doses of digoxin may have significant clinical implications in terms of present concepts of loading doses of digitalis in the pediatric age group.