We report a 33-year-old man presented to the emergency department with a chief complaint of typical angina three days before admission. An electrocardiogram showed arrowhead T-waves inversion in leads V1-V4, and the cardiac enzyme marker was increased. The initial diagnosis was non-ST-elevation acute coronary syndrome. On subsequent examinations, he had severe mitral stenosis, paroxysmal atrial fibrillation, and a history of intracranial hemorrhage. Diagnostic coronary angiography examination revealed myocardial bridging in the middle segment of left anterior descending coronary arteries. The patient was given dual antiplatelets (DAPT), beta-blocker, atorvastatin, and anticoagulant. Beta-blocker is the first-line therapy for myocardial bridging, whereas DAPT, anticoagulant, and high-dose statin therapy are used to treat acute coronary syndrome (ACS). The atherosclerotic process is commonly found in the proximal segment of myocardial bridging that can lead to ACS. In addition, mitral stenosis is one of the main causes of systemic embolism, including coronary embolism, while atrial fibrillation is known to increase the risk of embolism. Herein, we discuss the possible etiology of ACS, the management of myocardial bridging and comorbidity of this patient, and the rationale for selecting antithrombotic therapy.