The interaction between ACE2 and SARS-CoV-2 determines a disruption of the physiological renin–angiotensin–aldosterone system (RAAS)—which ACE2 is directly part of—modifying its normal protective functions against heart failure, myocardial infarction, hypertension, lung disease, and diabetes mellitus [26,27,28,29]. The gene discussed is ACE2; the disease is heart failure.