What does acute onset means in the context of Staphylococcus aureus infective endocarditis? Description of a hyperacute infective endocarditis

What does acute onset means in the context of Staphylococcus aureus infective endocarditis? Description of a hyperacute infective endocarditis. Repessé, Xavier; Charron, Cyril; Guérin, Laurent; Au, Siu-Ming; Vieillard-Baron, Antoine. Presse Medicale (Paris, France: 1983). 2016; 45: p.933-935. doi:10.1016/j.lpm.2016.05.018
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