BACKGROUND: Acute aortic dissection is known as the most dangerous aortic disease, with management and prognosis determined as the disruption of the medial layer provoked by intramural bleeding. The objective of this study was to evaluate the safety and necessity of antiplatelet therapy on patients with Stanford Type B aortic dissection (TBAD) who underwent endovascular aortic repair (EVAR). METHODS: The present study retrospectively analyzed 388 patients with TBAD who underwent EVAR and coronary angiography. The primary outcomes were hemorrhage, death, endoleak, recurrent dissection, myocardial infarction, and cerebral infarction in patients with and without aspirin antiplatelet therapy at 1 month and 12 months. RESULTS: Of those 388 patients, 139 (35.8%) patients were treated with aspirin and 249 (64.2%) patients were not treated with aspirin. Patients in the aspirin group were elderly (57.0 ± 10.3 years vs. 52.5 ± 11.9 years, respectively, χ2 = 3.812, P < 0.001) and had more hypertension (92.1% vs. 83.9%, respectively, χ2 = 5.191, P = 0.023) and diabetes (7.2% vs. 2.8%, respectively, χ2 = 4.090, P = 0.043) than in the no-aspirin group. Twelve patients (aspirin group vs. no-aspirin group; 3.6% vs. 2.8%, respectively, χ2 = 0.184, P = 0.668) died at 1-month follow-up, while the number was 18 (4.6% vs. 5.0%, respectively, χ2 = 0.027, P = 0.870) at 12-month follow-up. Hemorrhage occurred in 1 patient (Bleeding Academic Research Consortium [BARC] Type 2) of the aspirin group, and 3 patients (1 BARC Type 2 and 2 BARC Type 5) in the no-aspirin group at 1-month follow-up (χ2 = 0.005, P = 0.944). New hemorrhage occurred in five patients in the no-aspirin group at 12-month follow-up. Three patients in the aspirin group while five patients in the no-aspirin group had recurrent dissection for endoleak at 1-month follow-up (2.3% vs. 2.2%, respectively, χ2 = 0.074, P = 0.816). Four patients had new dissection in the no-aspirin group at 12-month follow-up (2.3% vs. 3.8%, respectively, χ2 = 0.194, P = 0.660). Each group had one patient with myocardial infarction at 1-month follow-up (0.8% vs. 0.4%, respectively, χ2 = 0.102, P = 0.749) and one more patient in the no-aspirin group at 12-month follow-up. No one had cerebral infarction in both groups during the 12-month follow-up. In the percutaneous coronary intervention (PCI) subgroup, 44 (31.7%) patients had taken dual-antiplatelet therapy (DAPT, aspirin + clopidogrel) and the other 95 (68.3%) patients had taken only aspirin. There was no significant difference in hemorrhage (0% vs. 1.1%, respectively, χ2 = 0.144, P = 0.704), death (4.8% vs. 4.5%, respectively, χ2 = 0.154, P = 0.695), myocardial infarction (2.4% vs. 0%, respectively, χ2 = 0.144, P = 0.704), endoleak, and recurrent dissection (0% vs. 3.4%, respectively, χ2 = 0.344, P = 0.558) between the two groups at 12-month follow-up. CONCLUSIONS: The present study indicated that long-term oral low-dose aspirin was safe for patients with both TBAD and coronary heart disease who underwent EVAR. For the patients who underwent both EVAR and PCI, DAPT also showed no increase in hemorrhage, endoleak, recurrent dissection, death, and myocardial infarction.