Stent-Grafts: A safe therapeutic option for patients with impending rupture of the chest aorta

Surgical repair of such aneurysms and interposition of vascular protheses were until recently the only treatment option for complicated cases (diameter „d 5.5 cm; impending rupture; malperfusion syndrome; recurrent pain). Although great strides have been achieved by improving surgical techniques, postoperative complications (such as persistent paralysis of both legs, stroke, acute renal failure or pulmonary dysfunction) and 30-day mortality remain high. Especially elderly patients with accompanying illnesses (high blood pressure, chronic pulmonary disease or heart failure) are at high risk. Therefore, these comorbidities have a significant impact on postoperative outcome and further life expectancy.

Conversely, endovascular stent-graft implantation seems to be a promising, non-surgical and less traumatic therapeutic option and avoids surgical opening of the chest. Endovascular protheses are based on the concept of a metal grid covered with graft material (Dacron). The natural healing process begins after complete sealing of the proximal entry tear in dissection (see figure 2) and induces thrombus formation in the false lumen and reconstruction of the aortic wall.

In our institution stent-graft placement was performed in the cardiac catheterization laboratory with patients under general anesthesia and ventilation. In all patients, the femoral or distal iliac artery was surgically exposed and the stent-graft was inserted, advanced and deployed inside the aorta with the use of fluoroscopy and simultaneous ultrasound. Once stent apposition was achieved, the catheter delivery system was removed, and the incision was surgically closed.

Between October 1997 and September 2002 105 patients were subjected to endovascular treatment of dissecting aneurysms in the chest aorta. This analysis describes the experience with this endovascular strategy in the largest reported group of patients. Delivery success was achieved in all patients. Early 30-day mortality was 2.8% and overall-mortality in the entire follow-up period (mean follow-up 32.4 „b 15.5 months, range 1 day – 64 months). was 10.5% (11 patients). Six patients died from late rupture of the chest aorta; additional five deaths were non-vascular.

Persistent neurological complications (strokes) after stent-graft implantation were observed in 2.8% during the entire follow-up period and temporary neurological complications without any residues in 7.6%. Persistent paralysis of both legs was not observed. Within midterm follow-up 6.6% of patients required a second adjunctive stent-graft intervention to seal secondary endoleaks or to treat progressive pathology of the aorta. Elective open surgery was necessary in 5.7% due to progression of aortic diameters with persistent perfusion of the false lumen.

Although our retrospective midterm-analysis after endovascular stent-graft placement suggests a beneficial outcome and confirms procedural safety, the concept of non-surgical aortic reconstruction should be subjected to randomized trials in order to demonstrate improvement of long-term prognosis for patients with dissecting aneurysms of the chest aorta. At this time such a European multi-center trial is ongoing (INSTEAD-study).

Professor Dr. med. Christoph A. Nienaber / Dr. med. Tim C. Rehders
Division of Cardiology, University of Rostock, Rostock, Germany

IMPORTANT: This press release accompanies a poster or oral session given at the ESC Congress 2003. Written by the investigator himself/herself, this press release does not necessarily reflect the opinion of the European Society of Cardiology
True aneurysms and dissecting aneurysms (see figure 1) of the chest aorta both represent life-threatening situations since with increasing diameters they tend to rupture and lead to fatal bleeding.