Cardiovascular mortality in peripheral artery disease (PAD) patients is higher in critical limb ischemia (CLI) than in intermittent claudication (IC). We sought to evaluate differential characteristics of coronary artery disease (CAD) severity and prognostic biomarkers for cardiovascular events between CLI and IC patients. Coronary angiography was performed on 242 PAD patients (age 73 ± 8 years) with either CLI or IC. High-sensitivity troponin T (hs-TnT), eicosapentaenoic acid-arachidonic acid ratio (EPA/AA), and lipoprotein(a), as biomarkers for prognostic factors, were measured from blood samples. The study patients were divided into a CLI-group (n = 42) and IC-group (n = 200). The Gensini score as an indicator of coronary angiographic severity was higher in the CLI-group than in the IC-group (39.1 ± 31.2 vs. 8.5 ± 8.3, p < 0.0001). Hs-TnT and lipoprotein(a) values were higher in the CLI-group than in the IC-group (0.152 ± 0.186 ng/mL vs. 0.046 ± 0.091, p < 0.0001, 45.9 ± 23.3 mg/dL vs. 26.2 ± 27.7, p = 0.0002, respectively) and EPA/AA was lower in the CLI-group than in the IC-group (0.22 ± 0.11 vs. 0.38 ± 0.29, p = 0.0049, respectively). Greater CAD severity, higher hs-TnT, and lipoprotein(a), and lower EPA/AA were observed in the CLI-group, which may explain higher cardiovascular events in patients with CLI.