Levy David, Sharma Sanjeev, Farci Fabiola, Le Jacqueline K.
Waikato Hospital
Pisa University
Aortic dissection, though uncommon, is a catastrophic vascular disorder characterized by a tear in the intimal layer of the aorta, leading to the separation of the aortic wall layers. Blood enters between the intima and media, propagating the dissection either proximally or retrograde, resulting in compromised blood flow to vital organs. Acute aortic dissection carries extremely high mortality rates, with many patients dying before reaching emergency care. Patients with chronic aortic dissection, defined as a dissection present for more than 2 weeks, have a slightly better prognosis. While the classic presentation of acute aortic dissection involves sudden, severe, “tearing” chest pain, subtle presentations often lead to missed diagnoses. Despite the literature, many aortic dissections are missed in the emergency department; only 15% to 43% of verified cases are accurately diagnosed at first presentation. Without treatment, mortality approaches 50% within 48 hours of symptom onset. Despite its rarity, acute aortic dissection requires prompt diagnosis and multidisciplinary healthcare intervention, with better outcomes observed in high-volume centers utilizing experienced teams, “aorta code” protocols, and specialized aortic centers. Further, implementing a multidisciplinary strategy with vascular surgery and cardiology expertise is essential to improving patient outcomes in these life-threatening cases. Aortic dissections are classified anatomically by 2 systems: the Stanford and DeBakey classification systems. The Stanford system categorizes dissections into 2 types based on whether the ascending or descending part of the aorta is involved (see Stanford Classification of Aortic Dissection). : Thisinvolves the ascending aorta, regardless of the site of the primary intimal tear (see Type A Aortic Dissection), and is defined as a dissection proximal to the brachiocephalic artery. This originates distal to the left subclavian artery and involves only the descending aorta; the Society for Vascular Surgery and the Society of Thoracic Surgeons define Stanford type B dissections as those where the entry tear occurs beyond the origin of the innominate artery. The DeBakey system further subdivides dissections into 3 types based on the origin and extent of the dissection: : Originates in the ascending aorta, aortic arch, and descending aorta. Originates in and is limited to the ascending aorta. Begins in the descending aorta and extends distally above the diaphragm (type 3a) or below the diaphragm (type 3b). Ascending dissections (Stanford type A or DeBakey types 1 and 2) are nearly twice as common as descending dissections (Stanford type B or DeBakey type 3), necessitating an urgent, specialized approach to reduce the risk of fatal complications such as aortic rupture, stroke, or myocardial infarction (see Aortic Dissection, Type A).
主动脉夹层虽然不常见，但却是一种灾难性的血管疾病，其特征是主动脉内膜层撕裂，导致主动脉壁各层分离。血液进入内膜和中膜之间，使夹层向近端或逆行扩展，导致重要器官的血流受损。急性主动脉夹层的死亡率极高，许多患者在到达急诊治疗之前就已死亡。慢性主动脉夹层患者（定义为夹层存在超过2周）的预后稍好一些。虽然急性主动脉夹层的典型表现是突发、剧烈的“撕裂样”胸痛，但症状不典型时往往会导致漏诊。尽管有相关文献报道，但许多主动脉夹层在急诊科被漏诊；初诊时只有15%至43%的确诊病例能被准确诊断。未经治疗的情况下，症状发作后48小时内死亡率接近50%。尽管急性主动脉夹层罕见，但需要迅速诊断并进行多学科医疗干预，在使用经验丰富的团队、“主动脉急救方案”和专业主动脉中心的大容量中心，观察到的治疗效果更好。此外，实施包含血管外科和心脏病学专业知识的多学科策略对于改善这些危及生命病例的患者预后至关重要。主动脉夹层按解剖学分为两种系统：斯坦福分类系统和德巴基分类系统。斯坦福系统根据主动脉升部或降部是否受累将夹层分为两种类型（见主动脉夹层的斯坦福分类）。：这包括升主动脉，无论原发内膜撕裂的部位如何（见A型主动脉夹层），定义为头臂动脉近端的夹层。：起源于左锁骨下动脉远端，仅累及降主动脉；血管外科学会和胸外科学会将斯坦福B型夹层定义为入口撕裂发生在无名动脉起源远端的夹层。德巴基系统根据夹层的起源和范围将夹层进一步细分为三种类型：：起源于升主动脉、主动脉弓和降主动脉。：起源于并局限于升主动脉。：始于降主动脉，向远端延伸至膈肌上方（3a型）或下方（3b型）。升主动脉夹层（斯坦福A型或德巴基1型和2型）的发生率几乎是降主动脉夹层（斯坦福B型或德巴基3型）的两倍，因此需要采取紧急、专门的方法来降低致命并发症如主动脉破裂、中风或心肌梗死的风险（见A型主动脉夹层）。
