Acute ischemic stroke (AIS) is one of the most common neurological emergencies, especially in elderly patients with high morbidity and mortality. The objective of this study is to evaluate the use of monocyte and high-density lipoprotein cholesterol (HDL-C) values, which play important roles in the inflammatory process after ischemia, in the prediction of 30-day mortality in patients. This is a retrospective, cross-sectional, observational study on demographic characteristics, vital signs and laboratory parameters of adult patients who were diagnosed with AIS and had atrial fibrillation (AF) rhythm in their electrocardiograms (ECGs) were retrospectively abstracted from hospital registry. The relationship of the laboratory values (i.e., monocyte count, blood HDL-C level and monocyte HDL-cholesterol ratio (MHCR)) were analyzed. Among 92 patients enrolled in the study, 54 (58.7%) were male, 31 (33.7%) of the patients had a yellow triage code, 61 (66.3%) were recorded as red. Sixty-nine patients (75%), had a history of chronic disease. While 86 (93%) of the patients were hospitalized to the wards, 5 (6%) were admitted into the intensive care unit and one patient (1%) was referred to another institution. The minimum duration of signs and symptoms varied between 1 hour and 240 hours (median 12 hours). Length of stay in the emergency department varies between 1 hour and 26 hours (median 4 hours). Monocyte counts of the patients were in the range of 310 to 1510 × 109/µL, (median 685 × 109/µL). Blood HDL-C level is in the range of 12–84 mg/dL, (median 40 mg/dL). The MHCR was in the range of 5.95–89.1 (median 18.2 and mean 19.7 ± 10.6). MHCR is not effective in predicting 30-day mortality in ischemic stroke patients due to AF who presented to the emergency department. It would be more appropriate to design more comprehensive, multicenter and prospective studies on this subject.