As many as 1/3 of patients with proven ACS have no chest pain at presentation. Among the more common alternative presentations (anginal equivalents) are dyspnea, diaphoresis, nausea/vomiting, and syncope/near-syncope.
Note also that the absence of pain does not confer a better prognosis. The overall in-hospital mortality rate for patients with painless presentations is 13% vs. 4.3% for patients with chest pain.
