INTRAVASCULAR ULTRASOUND IMAGING IN ACUTE AORTIC DISSECTION

Objectives. This study was performed to determine the potential of int ravascular ultrasound in the detection and delineation of aortic disse ction. Background. Intravascular ultrasound is a new technique capable of displaying real-time cross-sectional images of arterial vasculatur e. Its clinical use has been explored mostly in coronary and periphera l arterial circulation. Methods. Intravascular ultrasound imaging of t he aorta was performed using a 20-MHz ultrasound catheter in 28 patien ts with suspected aortic dissection. All patients underwent contrast a ngiography; 7 had computed tomography; and 22 had transesophageal echo cardiography. Results. Imaging of the aorta from the root level to its bifurcation was performed in all patients in an average of 10 min. No complications occurred. Dissection was present in 23 patients and abs ent in 5. In the patients without dissection, intravascular ultrasound revealed normal aortic anatomy. In all 23 patients with dissection, i ntravascular ultrasound demonstrated the intimal flap and true and fal se lumena. The longitudinal and circumferential extent of aortic disse ction, contents of the false lumen, involvement of branch vessels and the presence of intramural hematoma in the aortic wall could also be i dentified. In cases where aortography could not define the distal exte nt of the dissection, intravascular ultrasound did. Conclusions. Our e xperience in this series of patients with aortic dissection indicates that intravascular ultrasound could be valuable in the identification and categorization of aortic dissection and in the description of asso ciated pathologic changes that may be clinically important. It can be performed rapidly and safely and could serve as an alternative or adju nct diagnostic procedure in patients with aortic dissection.