REN and hydrops fetalis: Recent studies have shown that DM not only negatively affects patients with ischaemic cardiomyopathy and HF, but also patients with HF with non-ischaemic cardiomyopathy and preserved left ventricular systolic function.2,3 The linear relationship of DM and HF was established four decades ago.4 Often described as “diabetic cardiomyopathy”, it is mainly characterized by the intensification of atherogenesis, upregulation of the renin-angiotensin-aldosterone system, glycation of interstitial proteins and increased oxidative stress.56