Growth Rate of Aortic Diameter in Patients With Type B Aortic Dissection During the Chronic Phase

Abstract

Background-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. Methods and Results-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 (Ϫ1.4 mm/year) (PϽ0.0001). 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 (Pϭ0.0003). Conclusion-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.

In-hospital and Long-Term Results of Surgery for Acute Type A Aortic Dissection: 243 Consecutive Patients

“…Endovascular treatment is another option reported to be recommendable especially for its characteristic of thrombus formation in the false lumen. 20) In addition, endovascular treatment can be an effective approach, even for elderly or severely compromised patients.…”

Editor's Choice – Management of Descending Thoracic Aorta Diseases

“…202 Conversely, FL thrombosis has been associated with a slower growth rate. 172,173 Interestingly, partial distal FL thrombosis has been shown to be an independent predictor of mortality after hospital discharge in patients with a CTBAD. 174 The responsible mechanism may be increased FL pressure resulting from a large entry tear without outflow.…”

Time-resolved Three-dimensional Magnetic Resonance Velocity Mapping of Chronic Thoracic Aortic Dissection: A Preliminary Investigation

“…The wide variation of ‰ow velocity and slower helical ‰ow in the dilated lumen may be related to an increase in wall shear stress on the outer wall of the false lumen, which comprises fewer elasticˆbers. 3,19,21,22 In this study, 3 patients with enlarged patent false lumen in the thorax or abdomen showed this type of blood ‰ow patterns, and one patient with a growing ULP had slower helical ‰ow at the ULP. The false lumens with laminar ‰ow or ULPs with stagnant ‰ow did not enlarge in this study.…”

“…These results suggest that pathologically helical blood ‰ow, in addition to other risk factors, such as Stanford type, maximum diameter of the aorta, aging, hypertension, and atherosclerosis, may contribute to the deterioration of chronic thoracic aortic dissection. 2,3,5,8,21 This study has also suggested that preemptive surgery might prevent disease progression even in cases of slower helical ‰ow in the false lumen. Further studies with a larger patient population are needed to conˆrm these preliminary results.…”

“…[1][2][3] Contrast-enhanced computed tomography (CT) or 3-dimensional (3D) magnetic resonance (MR) angiography is the standard technique for diagnosing and classifying thoracic aortic dissection, visualizing mural thrombus, intramural hematoma, and ulcer-like projection (ULP), and following up patients with this disease. [3][4][5][6][7][8][9] However, the frequent involvement of renal arteries in aortic dissection 1,7 precludes the use of contrast agents in some patients with renal insu‹ciency and risk for contrast-induced nephropathy and nephrogenic systemicˆbrosis.…”