Background: Cardiovascular disease (CVD) is the predominant cause of mortality and morbidity globally. Statin therapy is an important part of managing cholesterol since it can help stop and treat atherosclerotic cardiovascular diseases (ASCVD). The aim of this study was to evaluate the effectiveness of statin therapy and the extent to which clinical practices comply with the 2018 ACC-AHA guidelines for the risk management of ASCVD. Methods: This retrospective descriptive analysis assessed the effectiveness of statin therapy and adherence to the latest ACC-AHA guidelines for managing ASCVD risk. After putting the participants into four risk groups, we looked at how well they followed the instructions for using statins. Results: According to the study's rules, 88.4% of patients were taking their medicine correctly, and 73.5% of patients were on statin therapy. The high adherence rate (81.0%) shows that taking statin medicine is necessary for better cardiovascular outcomes. However, it was found that 11.6% of patients were not taking statins correctly. This was either because they were not prescribed enough in the high-risk group or too much in the low-risk group. There was a strong link between taking statins and being older, being male, having been in the hospital before, and having other health problems such high blood pressure and diabetes (p < 0.05). Conclusion: The study's findings stress even more the need to keep improving statin medications and making sure that clinical processes follow the ACC-AHA guidelines for prescribing statins and assessing ASCVD risk. Future study should concentrate on the enduring impacts and strategies to reconcile the disparity between professional standards and clinical practice.