Interestingly, in the present study (comprising 63 MD patients), elevated Nt-proBNP levels were measured in three (5 %) MD patients only – although any abnormal cardiac findings were detected in 49 (78 %) and a reduced LV-EF was observed in 29 (46 %) of them by CMR. The gene discussed is NPPB; the disease is Menkes disease.