EFFECT OF MEDICAL AND SURGICAL THERAPY ON AORTIC DISSECTION EVALUATEDBY TRANSESOPHAGEAL ECHOCARDIOGRAPHY - IMPLICATIONS FOR PROGNOSIS AND THERAPY

Background. Aortic dissection still has a poor prognosis despite progr ess in therapy. Therefore, this prospective follow-up study was design ed to determine whether the degree of communication between true and f alse lumen in relation to the type of dissection, analyzed by transeso phageal echocardiography, influences the risk after initiation of medi cal or surgical therapy. Methods and Results. In eight centers, 168 pa tients (124 men and 44 women) of age range of 23-84 years with proven aortic dissection were examined by transesophageal echocardiography in the acute phase, after start of medical and/or surgical therapy, and during follow-up (0-65 months; mean, 10 months). Analyses were perform ed prospectively according to a detailed study protocol. Patients were subdivided by transesophageal echocardiography according to a modifie d DeBakey classification. Type I aortic dissection was found in 35%, t ype II aortic dissection in 17%, and type III aortic dissection in 48% . Preoperative mortality was 3%, 7%, and 2%, and survival rates were 5 2%, 69%, and 70%, respectively. Type III aortic dissection could be su bdivided into those with communication and antegrade dissection (ca) ( 50%), with communication and retrograde dissection limited to the desc ending aorta (cr desc) (10%), with dissection extended to the aortic a rch and ascending aorta (cr asc) (27%), and with noncommunicating (nc) aortic dissection (13%). An open false lumen with no thrombus formati on was present in types I, II, III ca and III cr asc aortic dissection in 17%, 21%, 39%, and 27% respectively, although it was most pronounc ed in types III nc and III cr desc (75% and 78%). During follow-up in patients who survived, thrombus was demonstrated in the false lumen in 80% of type I aortic dissection and 81% of types III ca and III cr as c. Open false lumen was seen in type II aortic dissection in 18%. Spon taneous healing was found in 4% with type II and 4% with type III aort ic dissection (mainly in patients with type III nc aortic dissection). Patients with fluid extravasation, pleural effusion, pericardial tamp onade, and periaortic effusion as well as mediastinal hematoma had a m ortality of 52%. Reoperations were necessary in 12-29%, with the highe st rate in patients with type III ca aortic dissection. Survival for p atients with types III nc and III cr desc aortic dissection was higher than those with types I, II, III ca, and III cr asc. Conclusions. Pre operative mortality appears to be reduced by transesophageal echocardi ography, allowing rapid initiation of treatment. Intraoperative and po stoperative mortality in aortic dissection remains high. Risk factors are fluid extravasation and an open false lumen with high communicatio n. Thrombus formation in the false lumen can be regarded as a good pro gnostic sign. Surgery appears to be only a first step in the treatment of aortic dissection. Second surgery or closure of entry sites based on intraoperative echocardiography may be considered to induce thrombu s formation and reduce aortic wall stress.