No abstract

Follow-up of 18 patients with aortic dissection (five with type I, one with type II, 11 with type III dissection according to DeBakey) by transesophageal, two-dimensional and color-coded Doppler echocardiography showed a persistence of the false lumen in five of seven patients (71%) after surgery and in nine of 11 patients (82%) after medical therapy. In two patients treated with surgery, the dissected part of the aorta had been resected, whereas in two patients treated medically, a progressive and complete obliteration of the false lumen was observed. In the false lumen, thrombus formation was absent in four, localized in four, and progressive in six patients. Flow within the false lumen could be registered in 14 patients, and two distinct flow patterns were differentiated (laminar biphasic flow or slowly circulating flow). Persisting intimal tears were visualized by two-dimensional echocardiography in four patients, whereas colorcoded Doppler showed an additional one to three intimal tears in the descending aorta in 10 patients. Flow across these intimal tears was biphasic in 75% of patients; that is, systolic flow was directed from the true to the false lumen with diastolic flow reversal. Unidirectional flow was detected in 25% of the communications, directed in 20%o from the true to the false lumen, serving as an entry only and in one (5%) as reentry only. Additional information concerning complications like extension of the dissection (one of 18 patients), localized dilatation of the aorta (two of 18 patients), mediastinal hematoma (one of 18 patients), or aortic regurgitation (three of 18 patients) were detected by this method. Concerning the morphologic findings and the detection of flow characteristics, the transesophageal approach was superior to conventional echocardiography especially in the descending thoracic aorta. Thus, transesophageal twodimensional and color-coded Doppler echocardiography seems to be an ideal method not only for the easy detection of aortic dissection but also for follow-up. (Circulation 1989;80:24-33 Transesophageal echocardiography overcomes these methodologic limitations and is of great diagnostic value because of high-quality cross-sectional images of the ascending and descending thoracic aorta even in patients in shock or on mechanical ventilation.23-30 Surgery without further diagnostic investigation has been performed successfully in emergency cases.30 In combination with color-coded Doppler flow imaging, which superimposes flow information

Using the transesophageal approach the descending part of the aorta can be imaged by two-dimensional enchocardiography in cross sections comparable to computer tomograms. The value of combined transesophageal and transthoracic echocardiography was evaluated in 53 patients who were studied consecutively from 1983 to 1986 with symptoms of aortic dissection and compared with computed tomography, angiography, surgery and/or autopsy. In all patients the transthoracic aorta could be visualized and the dissection could be classified according to DeBakey: in 9 of 29 patients (34%) type I dissection, in 4 (14%) type II dissection and in 16 (55%) type III dissection was found. Operation was carried out because of acute symptoms in 11 of the 29 patients, and 3 additional patients died before operation. In 24 patients aortic dissection could be ruled out. A sensitivity of 97% for transthoracic and transesophageal echocardiography, of 80% for computed tomography and of 78% for angiography was calculated. The specificity for echocardiography was 100%, for computed tomography 100% and for angiography 95%. The positive predictive accuracy for echocardiography and computed tomography was 100% and 95% for angiography. The negative predictive accuracy for echocardiography was 96%, for computed tomography 77% and for angiography 79%. In no patient was an aortic dissection found by computed tomography or angiography which was not detected by echocardiography. In 1 patient with a large ectasia of the aorta ascendens aortic dissection was overlooked as retrospective analysis demonstrated. Signs of aortic insufficiency and pericardial effusion were detected.(ABSTRACT TRUNCATED AT 250 WORDS)