A Prospective Study of Medically Treated Acute Type B Aortic Dissection

Abstract

Objective: To study prospectively aneurysm formation, need of surgery, incidence of rupture and mortality in patients with conservatively treated acute type B aortic dissection.Methods: All patients referred to us with acute type B dissection between January 1990 and December 2001 were candidates for this prospective treatment and follow-up study. Patients deemed not to be in need of acute surgical repair were included after aggressive antihypertensive treatment. The follow-up protocol included close blood pressure control, clinic visits with physical examination, chest x-ray and spiral CT or MRI at 3 and 6 months and annually thereafter.Results: Sixty-six patients were followed for a mean of 79 months (range 22-179). The actuarial survival rate was 82% at 5 years and 69% at 10 years. Eighty-five percent remained free from dissection-related death at 5 years and 82% at 10 years. Ten patients (15%) developed aneurysm (Ͼ6 cm) of the dissected aorta. Three of these 10 patients died from aortic rupture and 2 underwent elective surgical repair. Of the 56 patients without aneurysm, one died from rupture and one died suddenly for causes unknown. One patient was treated with endovascular stent-graft. Five patients sustained a new type A aortic dissection which in all but one were fatal. In 26 patients the initial dissection was categorized as intramural hematoma. Twelve of these patients had, in addition to the hematoma, areas with localized dissection/ulcer-like projection. The latter was found to be a predictor of aortic event (dissection-related death, rupture, new type A aortic dissection, aneurysm formation) during follow-up, as was an initial diameter of Ͼ4.0 cm at first CT-scan during the acute event.Conclusions: Conservatively treated acute type B dissection has a low incidence of aneurysm formation and rupture during the chronic phase. These results must be matched or improved upon before endovascular stent-grafting or early aortic surgical repair can be regarded as the primary treatment of choice.

Retrograde Type A Aortic Dissection After Endovascular Stent Graft Placement for Treatment of Type B Dissection

“…34 -37 Hata et al 36 investigated the prognosis of 180 patients with acute type B dissection under medical management, and newly developed type A dissection was observed in 4 cases. Winnerkvist et al 37 reported new type A dissection developing in 5 of 66 candidates in a prospective study of medical treatment of acute type B dissection. Furthermore, some of patients with post-stent grafting type A dissection had a spontaneous new entry irrelevant to the endoprosthesis.…”

Editor's Choice – Management of Descending Thoracic Aorta Diseases

“…168 Aortic related complications may occur in 20e50% of patients with CTBAD. 169 Overall, it is estimated that approximately 20e40% of patients with CTBAD develop enlargement of the FL that warrants treatment and approximately 25% of DTAA or TAAA are associated with AD. 170 Aside from aneurysmal degeneration, aortic related complications include recurrent dissection, retrograde dissection, and rupture of the FL.…”

“…171 Hypertension, an aortic diameter of 40 mm or more in the acute phase, chronic obstructive pulmonary disease, and patency of the FL have been recognized as risk factors for late aneurysmal degeneration. 169 In addition, the presence of an entry tear larger than 10 mm in diameter or located in the arch or proximal DTA has been recognized as a predictor of late mortality and the consequent need for aortic repair. 168 Moreover, in patients treated for type A dissection with a patent distal FL, a large area of the FL (>70% of the total aortic area) is considered to be a predictor of aneurysmal degeneration.…”

“…Without interventional therapy, a substantial proportion of these patients will go on to develop a large aneurysmal chronic dissection that may require therapy. 169 Treatment of chronic dissections is difficult and from an endovascular perspective, requires extensive thoracic coverage because of poor aortic plasticity. It has been hypothesized that a subset of patients with sub-acute dissection (between 2 and 12 weeks after the index process), could be identified on the basis of morphological and physiological characteristics that predispose to formation of aneurysmal chronic dissection.…”

Prognosis for Patients With Type B Acute Aortic Dissection Risk Analysis of Early Death and Requirement for Elective Surgery

“…17 Genoni et al found that freedom from subsequent aortic surgery was approximately 80%. 18 These results are similar to those reported here, and are considered satisfactory.…”