Objective: This study compared the efficacy and safety of warfarin in specialized international normalized ratio (INR) outpatient clinic (INR-C) and in general cardiology outpatient clinic (General-C).Methods: Herein, 381 consecutive patients with a regular follow-up at INR-C (n=233) or General-C (n=148) for at least 1 year were retrospectively included. While INR-C patients were followed by a single experienced trained nurse, General-C patients were followed by a different cardiologist who worked in a rotational principle every month. During controls, demographic characteristics, INR levels, bleeding events, ischemic stroke, and transient ischemic attacks in the last 1 year were recorded. Primary endpoint was defined as the evaluation of the combined major bleeding and ischemic event, and secondary endpoint was defined as the evaluation of them separately.Results: The mean age of the patients was 62±12.86 and 43.8% were male. Mean time in therapeutic range (TTR) level was statistically higher in INR-C than that in General-C (68.8%±15.88 and 51.6%±23.04, respectively; p<0.001). Primary outcomes were significantly higher in General-C than that in INR-C [13.5% (20) and 6.4% (15); respectively, p=0.020]. Overall, major bleeding was observed in 25 patients (6.5%) and (2.6%) ischemic event was observed in 10 patients. In General-C patients, both major bleeding (8.8% vs. 5.2%; p=0.163) and the ischemic event (4.7% vs. 1.3%; p=0.051) were more, and no statistically significant differences were detected between the two clinics.Conclusion: The findings of our study demonstrate that patients followed in INR-C had higher TTR levels and lower bleeding and ischemic events rates that those followed in General-C.