REN and heart failure: Most likely, the development of an unfavorable DC in this collective is similar to those with heart failure or acute myocardial infarction.[18,28] Neurohumeral adaptions like the activation of both the sympathetic nerve and the renin–angiotensin–aldosterone system induce an inability of the ANS to react to vagal influences.[29] DC is an integral measure of the ability to oscillate the heart rate and can quantify this imbalance.