Background: The management of the aortic root in type A aortic dissection (TAAD) is challenging. Conservative aortic root repair is considered a reasonable option in most cases. This study aimed to analyze medium-term mortality and aortic root reintervention after TAAD. Methods: All patients with TAAD underwent prospective follow-ups between 2017 and 2021. The primary endpoint was the increase in aortic root diameter and the rate of proximal root reintervention. The secondary endpoints were the risk factor and location for root-RAD, and risk factors for severe and moderate AR and mortality during follow-up. Results: A total of 210 patients were included, of which 166 (79.0%) did not have root-RAD and 44 (21.0%) had root-RAD after supracoronary aortic replacement. After a mean follow-up of 41.1 months (0–60), four patients (1.8%) died. No cases of aortic root rupture were reported. Two patients in the root-RAD group underwent aortic root reoperation. The aortic root diameter increased by 0.5 mm/year and 0.09 mm/year in the root-RAD and no-root-RAD groups, respectively (p = 0.18). Root-RAD was a risk factor for severe AR (HR 19.6; 95%CI: 1.6–2.7; p = 0.05) and an independent risk factor for moderate AR (HR 23.0; 95%CI: 2.8–2.9; p = 0.009). Conclusions: Without increasing long-term mortality, root-RAD increases the risks of AR and subsequent aortic root reintervention. Long-term follow-up is essential for monitoring aortic valve function.