Naokazu Kinoshita

Flow Velocity Measurement and Differentiation Between True and False Lumens in Patients with Abdominal Aortic Dissection by Use of Pulsed Doppler Echocardiography

Feasibility of differential diagnosis between the true and false lumens was studied with pulsed Doppler echocardiography in 8 patients with abdominal aortic dissection. The blood flow signal was obtained in both lumens in 7 of the 8 patients and in only the true lumen in the remaining 1 patient. The blood flow pattern was abruptly changed when the sample volume was moved from the true lumen to the false one. The peak flow velocity was higher in the true lumen (95 ± 19 cm/sec) than in the false one (28± 12 cm/sec) and ejection flow duration was longer in the former (306 ±103 ms) than in the latter (163 ±53 ms). The appearance time of ejection flow was not different between them. The presence of reverse flow during the ejection phase was more frequent in the false lumen (5/7) than in the true one (2/8). Thus, the conventional pulsed Doppler study may provide useful information in making a differential diagnosis between the true and false lumens in patients with abdominal aortic dissection.