Treatment of Children Suffering from an Inborn Error of Mitochondrial Fatty Acid p-Oxidation with Cardiac Glycosides and Antiarrhythmics During Acute Metabolic Decompensation

Treatment of Children Suffering from an Inborn Error of Mitochondrial Fatty Acid p-Oxidation with Cardiac Glycosides and Antiarrhythmics During Acute Metabolic Decompensation

Birutė Skerlienė, Odeta Kinčinienė, Willy Lehnert

Summary

Frequently primary or secondary mito­chondrial fatty acid ß-oxidation (FAO) defects are causing acute metabolic de­compensation. Inborn errors of fatty acid metabolism are also important causes of reversible cardiomyopathy in infancy. In­sufficient mitochondrial ß-oxydation of the main substrates suppress the func­tion of myocardium. Long-chain acyl- carnitines and other pathol ogic metabo­lites cause damage of mitochondrial membranes, disturb action of the ATP-de- pendent ion pumps and the corresponding ionic equilibrium, inducing thereby cardiac arrhythmia and destruction of cardio­myocytes. Etiopathogenesis of heart failure and arrhythmias in infants with inborn FAO defects, the pharmacodynamic char­acteristics of cardiac glycosides (CG) and some antiarrhythmics (AA) as well as cor- reiafion of their side effects with injured mitochondrial FAO is discussed, present­ing a clinical cases as an example. The cardiomyopathy in infant was demon­strated to be reversible as a result of the suspition of the inborn FAO deiect and the homeostasis correction in due time. The unreversible myocardium damage possibly aggravated by CG and amiodarone was demonstrated in infant with the ho meo sta sis al ter ations not cor­rected in prompt way. Metabolic distur bances in cardiomyocytes can be wors­ened by CG and AA during acute decom­pensation. In some cases uncommon side effects of CG and AA can be caused by an undiagnosed FAO defect.

Keywords: cardiomyopathies, myo­carditis, heart failure, arrhythmia, cari diac glycosides, amiodarone, mitochon­dria, ion channels, fatty acid oxidation, inborn defects.