Acute aortic dissection type A (AADA) is a cardiovascular emergency and necessitates immediate diagnosis and subsequent surgical treatment to overcome the risk of preoperative deterioration and death [2, 5]. Further, the associated postoperative mortality is still hard to predict prior to the surgical procedure or when explaining the situation to the patient or to the patient’s relatives (e.g. if the patient is unconscious) in the emergency room. As risk factors associated with postoperative mortality, there have been many reports, however, it remains controversial.
In the present study, because the actual 30-day mortality rate of the study cohort was low (6%) compared to calculated GERAADA score (14.3%), our results could not reveal the significant statistical relationship between the GERAADA score and 30-day mortality. However, the GERAADA score revealed significant correlation with peri- and post-operative factors. Therefore, GERAADA score may impact on the postoperative course. Czerny et al. stated that the GERAADA score is not meant as an apodictic instrument for accepting or rejecting treatment but is meant to serve as a useful instrument to be able to anticipate postoperative outcome according to very basic and easily retrievable parameters [8, 9]. Pollari et al. stated that the best use of the new GERAADA score should not be the patient selection or the decision-making but rather the quality control and the performance comparison between different hospitals for the retrospective evaluation and better resource management purposes [18]. For these reasons, The GERAADA score can be a useful predictor of other postoperative course as well as 30-day mortality.
In addition, parameters such as the time from onset to arrival at the hospital, time from onset to arrival at the operation room, spouse presence, and hemodialysis were significantly associated with early mortality.
Goda et al. described renal dysfunction defined by a serum creatinine concentration of more than 2.0 mg/dL, was a preoperative independent risk factor for hospital mortality in AADA surgery [11]. According to Mehta et al., as variables predicting in-hospital death after AADA surgery, kidney failure was given the highest score [12]. As shown in these reports, preoperative renal dysfunction has been reported to increase the operative risk of aortic repair for patients with AADA, however, there have been little debate about hemodialysis. Akiyoshi et al. reported that the difference was not statistically significant between hemodialysis group and non-hemodialysis group although the in-hospital mortality rate was increased in hemodialysis group [13]. Since aortic dissection is somewhat rare in hemodialysis patients, further studies on the effects of hemodialysis on the outcome of AADA are warranted.
Not to mention, timely diagnosis is essential for successful management in AADA. Nakai et al. described that time from symptom onset to operation within 5 hours is a significant predictor of long-term survival among patients with AADA and preoperative malperfusion [14]. According to Harris et al., a median time to diagnosis of 4.3 hours plus an additional 4.3 hours from diagnosis to surgery indicates that there is a significant opportunity for systematic improvement [15]. The authors reported that some patient groups, such as patients who transfer from other hospitals, those without pain, nonwhites, and those with prior cardiac surgery, are prone to delays in treatment [15]. In the present study, time from onset to arrival at the hospital and time from onset to arrival at the operation room were significantly associated with 30-day mortality. Moreover, interestingly, those related with lower GERAADA scores were referred patients from other hospitals. This explains that critically ill patients are not in time for referrals and transport alive. In order to save time, it is critical to establish acute aortic syndrome network consisting experienced aortic centers as well as prompt diagnosis with advanced imaging technology. In addition, we endorse the crucial role of modern dedicated specialized aortic centers in treating acute aortic syndromes.
Although there have been no reports about relationship between aortic dissection and family background, the relationship between coronary artery disease and family background has been described [16, 17]. Single men and women with myocardial infarction reportedly had an increased mortality compared with married participants [16, 17]. Although the causal relationship is still unclear, there have been data describing that singles are prone to fatal myocardial infarction. Further studies on the relationship between AADA and family background are warranted.
This study is had some limitations. First, relatively few patients were included owing to the rarity of this condition. Second, this was a retrospective single-center experience lacking any form of randomization. Third, the surgical technique for AAAD has evolved during the time of this study. To resolve these limitations, a multi-institutional study is needed. Further, a prospective clinical trial is required to further evaluate the new GERAADA score as a useful tool to allow for improved decision- making in the emergency setting of AADA. Moreover, public-health management strategies that would reduce the time from onset to admission are needed.