The relationship between 1-year mortality and infarct location in patients with non-Q wave myocardial infarction.

The association between 1-year mortality and infarct location was evaluated in 544 patients with acute non-Q wave myocardial infarction. Infarcts were anterior (alone or including other locations) in 51.1% (n = 278) of cases, localizable but not anterior 29.6% (n = 161) of the time, and nonlocalizable in 19.3% (n = 105) of patients. One-year actuarial mortality (73 deaths) was 16.9% in the anterior group, 13.3% in the nonanterior group, and 6.8% in nonlocalizable patients (p = 0.037). Anterior and localizable nonanterior mortality were similar (p = 0.367). However, there were differences when mixed location infarcts were excluded. Mortality in the inferior infarction only group (2.8%, n = 36) was less than in the lateral infarction only group (16.8%, n = 79, p = 0.041) and almost significantly less than in the anterior only group (15.1%, n = 62, p = 0.064). The positive prognosis in the inferior infarction only group may be associated with the low rate of ST depression among these patients compared with those with other infarct locations (p less than 0.0001). Mortality among localizable infarcts (15.5%) was greater than among those that were nonlocalizable (6.8%, p = 0.021). Despite the low overall risk of the nonlocalizable infarcts, 41.9% (n = 44) of these patients developed at least one important risk factor while in hospital.(ABSTRACT TRUNCATED AT 250 WORDS)