Tango 2 Case Series: Cardiac Manifestations

Tango 2 mutation causes a rare paediatric metabolic condition, which is associated with sudden onset of metabolic crises and accompanying cardiac sequelae. These crises can be associated with sudden and transient QT interval prolongation with associated ventricular arrhythmia and severe but reversible dilated cardiomyopathy. This case series documents the presentation of three paediatric patients who presented with acute life-threatening cardiac manifestations of Tango 2 mutation in the setting of metabolic crises. Retrospective case series of three cases with documentation of ECG findings, echocardiographic findings and in relationship to the timeline of the metabolic crises. All three patients in this series presented with severe and sudden onset of new cardiomyopathy and ventricular arrhythmia. All cases experienced transient and significant QT prolongation and subsequent torsade de pointes associated with the metabolic crises. One patient died during the course of the illness, secondary to arrhythmia and cardiomyopathy. Two of the patients had reversible severe dilated cardiomyopathy, with one of these receiving Extra Corporeal Membrane Oxygenation (ECMO). In both of these remaining cases, the cardiomyopathy improved over several months following treatment of the metabolic crisis. Tango 2 mutation is a rare metabolic condition which can be associated with life threatening cardiac manifestations. These are transient and resolve with treatment of the underlying metabolic crisis. This series highlights the importance of identifying prolongation of the QT interval early in the course of metabolic crisis, so that management of subsequent arrhythmias and cardiomyopathy can be instituted in an intensive care setting.