[Surgical therapy of thoracic aortic dissection]

Considerable surgical progress of treating aortic dissection has been achieved during the past decade. The emergency indication for acute dissection of the ascending aorta (type A according to the Stanford classification) is unquestioned while surgical treatment for acute dissection of the descending aorta (type B dissection) is mainly reserved for complicated cases. The major complication of acute operations--fatal hemorrhage from the suture line and secondary multi-organ failure--have been successfully reduced by a progress of cardiopulmonary bypass techniques, the introduction of cold cardioplegic myocardial protection, the development of modern suture materials and glues and last not least by a continuous intensive monitoring. Especially the introduction of the so-called french glue safely enabled both the closure of the false lumen as well as the strong reinforcement of the diseased aortic wall and seems to offer a reliable alternative to the application of multi-layered teflon strips. Since the principle of all reconstructive approaches in case of dissection consists of closure of dissected layers and the limited replacement of the segment that is susceptible to a rupture the exact readaptation and reinforcement of the diseased aortic wall represents a fundamental operative step. In type A operations the supracoronary aortic prosthetic replacement or the combined replacement of ascending aorta plus aortic valve followed by the reattachment of coronary arteries has become the standard operative technique. In fact, independently from the location of the primary intimal tear the operation has been traditionally limited to replace the ascending aorta in order to remove an aortic segment that is most likely to rupture. Yet an increasing number of follow-up investigations has demonstrated recurrence of dissection or an aneurysmatical dilatation of the false lumen in about 20% of patients treated with ascending aortic replacement. Consequently, repair of the aortic transverse arch and the radical elimination of the intimal entry is now favoured by an increasing number of surgeons. In addition to these various perioperative and intraoperative adjuncts the introduction of new imaging techniques, especially computerized tomography, magnetic resonance imaging and transesophageal echocardiography allowed to establish adequate therapeutical concepts on a more rational basis. Transesophageal echocardiography as a mobile diagnostic device enables investigators to perform a bed-side dynamic visualization of both the location and extent of a dissection, the evaluation of ventricular performance and aortic competence. Treatment of acute type B dissection is mainly conservative unless complications like intractable pain, aneurysmatic enlargement of the false lumen, ischemia of visceral organs or even rupture occur.(ABSTRACT TRUNCATED AT 400 WORDS)