Taken together, the key role of ACE2 in SARS-CoV-2 infection, the strong binding affinity of SARS-CoV-2 to the ACE2 receptor, and the documented severity of COVID-19 in subjects with respiratory, cardiovascular and metabolic conditions led us to hypothesize that pulmonary vasoconstriction and impaired airway SMC metabolic homeostasis resulting from robust SARS-CoV-2 virus-induced ACE2/Ang II regulatory imbalance might prevail over the diverse immune response at the initial phase of COVID-19 pathogenesis. Here, ACE2 is linked to COVID-19.