Hemoglobin (Hb) is an essential hematological parameter, and its deviations from the physiological range can have important implications for cardiovascular health. Anemia is associated with chronic inflammation, oxidative stress, and endothelial dysfunction, increasing the risk of cardiovascular events, while elevated hemoglobin levels can cause high blood viscosity, tissue hypoxia, and thrombotic risk. A retrospective study was conducted on 100 adult patients, using data from standard hemograms. The parameters analyzed included Hb, hematocrit (Hct), leukocytes (WBC), platelets (PLT), age, and gender. The prevalence of anemia (Hb <12 g/dL in women, <13 g/dL in men) and elevated Hb values (>16 g/dL in men, >15 g/dL in women) was evaluated, as well as the correlations between Hb and other hematological parameters. Anemia was identified in 18% of patients, being more frequent in women over 65 years of age. Elevated Hb values were observed in 7% of patients, predominantly in young men. Hb showed a strong correlation with Hct (r=0.82, p<0.001), while the correlations with WBC (r=0.24) and PLT (r=0.18) were moderate and statistically insignificant. Extreme Hb values were associated with hematological changes suggestive of increased cardiovascular risk, including tissue perfusion disturbances and thrombotic predisposition. Hemoglobin values, either low or high, may constitute adjunctive hematological markers of cardiovascular risk. Integrating Hb into clinical evaluation, together with other hematological parameters and traditional risk factors, may support the identification of patients at high risk and the orientation of preventive interventions. These results provide a solid basis for future research on the role of Hb as a clinical marker in cardiovascular risk stratification.