Nausea and vomiting occurring during myocardial ischemia is believed to be associated with inferior wall infarction. However, data supporting such an association are limited, and an alternative hypothesis that cardiac vomiting is related to infarct size has also been advanced. The 2 hypotheses were tested in a cross-sectional study of 265 patients consecutively admitted to the coronary care unit. Nausea or vomiting was a good predictor of myocardial infarction (p less than 0.0001). The odds of having an infarction was 3.14 times greater for patients with nausea or vomiting than for those without these symptoms. Nausea was not a good predictor for inferior wall infarction (p = 0.14): 51% of patients with inferior infarcts had nausea or vomiting and 66% with anterior infarcts had these symptoms. Using peak serum creatine kinase level as an index of infarct size, nausea or vomiting was a good predictor of larger infarction. While 55% of all patients with infarction had nausea or vomiting, for patients with infarctions that produced a peak creatine kinase level of more 1,000 IU/liters, 78% had nausea or vomiting. Sex was a marginally important variable. After adjusting for sex, the presence of nausea or vomiting still predicted infarct size (p less than 0.001). Thus, cardiogenic nausea and vomiting are associated with larger myocardial infarctions but do not suggest infarcts in a particular location.