Sueyoshi Eijun, Sakamoto Ichiro, Hayashi Kuniaki, Yamaguchi Tetsuji, Imada Tatuya
Department of Radiology, Nagasaki University School of Medicine, 1-7-1 Sakamoto, Nagasaki 852-8501.
Circulation. 2004 Sep 14;110(11 Suppl 1):II256-61. doi: 10.1161/01.CIR.0000138386.48852.b6.
The purpose of this study was to evaluate the growth rate of type B double-barrel aortic dissection with computed tomography (CT) and the factors influencing its enlargement.
Sixty-two patients were entered into this study, and regular follow-up CT studies (mean; 49.1 months) were performed. The affected aortas and iliac arteries were divided into 5 segments (aortic arch, descending thoracic, suprarenal abdominal, infrarenal abdominal aorta, and iliac artery). Fifty-two of 62 patients (83.9%) had 1 or more segments increased in size during follow-up period. In a total of 177 segments, the presence or absence of blood flow in the false lumen and aortic diameter were evaluated on CT during the follow-up period. The factors (gender, diabetes mellitus, atherosclerotic disease, smoking, entry site in arch, initial diameter, chronic obstructive pulmonary disease, blood pressure, and age) influencing increase in the diameter and growth rate were also evaluated. Of 177 segments, 132 segments (74.6%) increased in size during the follow-up period. The presence of blood flow in the false lumen was the only significant risk factor for increase in the diameter in the univariate and multivariate analysis. The group with blood flow in the false lumen had a significantly higher mean growth rate (3.3 mm/year) than the group without blood flow (-1.4 mm/year) (P<0.0001). The growth rate of aortic dissections in thoracic aorta and abdominal aorta were 4.1 and 1.2 mm/year, respectively. There was a significant difference in the growth rate between the 2 groups (P=0.0003).
In type B aortic dissection, the affected aortas have shown a high incidence of enlargement during the follow-up period, and more careful follow-up study is needed for aortic dissections in the thoracic aorta. The presence of blood flow in the false lumen is the most important risk factor for aortic enlargement.
本研究旨在通过计算机断层扫描（CT）评估B型双腔主动脉夹层的生长速率及其影响扩大的因素。
62例患者纳入本研究，并进行了定期随访CT检查（平均49.1个月）。将受累的主动脉和髂动脉分为5段（主动脉弓、胸降部、肾上腺上方腹主动脉、肾上腺下方腹主动脉和髂动脉）。62例患者中有52例（83.9%）在随访期间有1个或更多节段增大。在总共177个节段中，随访期间通过CT评估假腔内有无血流及主动脉直径。还评估了影响直径增加和生长速率的因素（性别、糖尿病、动脉粥样硬化疾病、吸烟、主动脉弓入口部位、初始直径、慢性阻塞性肺疾病、血压和年龄）。在177个节段中，132个节段（74.6%）在随访期间增大。单因素和多因素分析显示，假腔内有血流是直径增加的唯一显著危险因素。假腔内有血流的组平均生长速率（3.3 mm/年）显著高于无血流的组（-1.4 mm/年）（P<0.0001）。胸主动脉和腹主动脉夹层的生长速率分别为4.1和1. mm/年。两组间生长速率有显著差异（P=0.0003）。
在B型主动脉夹层中，受累主动脉在随访期间显示出较高的扩大发生率，对于胸主动脉夹层需要更仔细的随访研究。假腔内有血流是主动脉扩大的最重要危险因素。
