The management of acute aortic aneurysm rupture or dissection (AARD) requires specific medical expertise, diagnostic techniques, and therapeutic options, not always available in all hospitals through the entire week. The aim of our study was to evaluate whether an association exists between weekday (WD) or weekend (WE) admission and mortality for patients with ARRD.Based on the database of routinely collected hospital admissions of the region of Emilia Romagna (RER) of Italy, we examined the discharge sheets of all patients with AARD (January 1999 to December 2009). The risk of in-hospital death was calculated for admissions on the WE compared with the admissions during a WD.The analysis considered 4559 events in 4461 patients. AARD admissions were most frequent on Monday (14.7%) and Friday (14.8%) and less frequent on Saturday (12.6%). The percentage of events admitted on Sunday/holiday was 15.0%, whereas the distribution of death rate with respect to day of admission was significantly different (χ(2) = 23.472; P < .001) with the highest frequency peak on Sunday/holiday (17.4%) and the lowest on Tuesday (12.9%). WE admissions were associated with significantly higher in-hospital mortality (43.4%) than WD admissions (36.9%, P < .001). Multivariate regression analysis showed that WE admission was an independent risk factor for increased in-hospital mortality odds ratio 1.318; 95% confidence interval, 1.144-1.517; P < .001).Our findings show that hospitalization for AARD on WE is associated with a significantly higher mortality rate than hospitalization on WD. Further studies are needed to investigate whether ensuring optimal diagnostic and therapeutic approaches during the entire week might improve the overall survival of patients with ARRD.