A neonate with a spongy failing heart - What could it be?

A neonate born of third-degree consanguineous marriage presented on day 12 of life with congestive cardiac failure. A male sibling died at 3 months of age, cause of which was not known. He was treated with decongestive measures and multiple inotropes. 2D Echocardiogram revealed severe Left ventricular dysfunction with prominent trabeculations and deep recesses in the left ventricle suggestive of Left ventricular non-compaction. He was also found to have horse-shoe kidney. Considering the presence of cardiac left ventricular non compaction, horse-shoe kidney and family history of neonatal death and pregnancy loss clinical exome sequencing was done. It detected a homozygous missense variant in exon 6 of the AGK gene suggestive of Senger's syndrome. Baby was on regular follow-up and was thriving well on diuretics, sacubitril-valsartan and weekly levosimendan infusions. At 8 months of age, cardiac transplantation was successfully done and baby has been doing well post-transplantation. LVNC in children is rare with an estimated incidence of 0.11 per 100,000, the highest incidence being during infancy. Senger's syndrome is autosomal recessive in inheritance. Senger's syndrome associated with Left ventricular non compaction has been reported only once in literature so far. Renal manifestations in the form of horse shoe kidney like in our index baby has not been reported previously with Senger's syndrome.