European Journal of Cardio-Thoracic Surgery, Vol 11, 1163-1169, Copyright © 1997 by European Association for Cardio-thoracic Surgery
Early and late outcome of operated and non-operated acute dissection of the descending aorta
J Gysi, T Schaffner, P Mohacsi, B Aeschbacher, U Althaus and T Carrel
Clinic for Thoracic and Cardiovascular Surgery, University Hospital of Berne, Switzerland.
OBJECTIVE: At present debate continues concerning the optimal mode of
treatment for type B dissections. Controversies are mainly due to
discordant results regarding survival following medical or surgical
treatment. We assessed early and long-term outcome of acute dissection of
the descending aorta treated by emergency aortic replacement, medical
treatment or delayed surgery. METHODS: Between 1980 and 1995, 225 patients
were hospitalized in the medical or surgical department of our institution
with the diagnosis of acute type B aortic dissection. A total of 38
patients (16.8%) underwent replacement of the descending aorta within the
first week after hospital admission. Primary indications for immediate
surgery were: rupturing aneurysm (n = 15), diameter of the descending aorta
(n = 13), malperfusion of the thoracoabdominal aorta (n = 8) and
pseudocoarctation syndrome with uncontrollable hypertension (n = 2). All
other patients (n = 187) underwent primary conservative treatment on the
intensive care unit, including appropriate anti-hypertensive medication. In
12 of them, surgery was denied because of age or significant concomitant
diseases. RESULTS: Hospital mortality after urgent or emergency surgery was
21% (8/38 patients) for the overall time period. There has been a
significant decrease in hospital mortality during the last 5 year- period
(12% versus 30% between 1980 and 1994). Causes of death were: cardiac
failure in 3, bleeding complications in 2, postoperative mesenteric
ischemia in 2 and septicemia in one patient. From the 30 operative
survivors, 9 (30%) patients required further surgery on the native aorta
after a mean follow-up of 48 +/- 13 months. Hospital mortality during
conservative treatment was 17.6% (33/187 patients). Main causes of death
were rupture in 14, thoraco-abdominal malperfusion in 13 and cardiac
failure in 3 patients, whereas in 3 patients, the cause of death could not
be evaluated. In this group, 9 patients had to be shifted to early surgery
during the initial hospitalization because of impending rupture (n = 4),
rapidly increasing diameter (n = 2) and suspicion of intestinal ischemia (n
= 3). After hospital discharge, surgery for chronic dissection was
performed in 47 patients, mainly because of expanding descending aortic
aneurysm. Hospital mortality was 8% (4/47 patients). Actuarial survival
rates after surgery during the first admission were 85 +/- 6% at 5 years
and 61 +/- 8% at 10 years, versus 76 +/- 5 and 50 +/- 7% respectively,
following conservative treatment (P < 0.001). CONCLUSION: Nowadays,
acute type B dissection can be treated surgically with a reasonable
perioperative risk. Despite aggressive anti-hypertensive treatment,
hospital mortality of primary conservative treatment is still high and a
substantial percentage of patients requires surgery during initial
hospitalization. Main causes of death in both groups are rupture and
abdominal malperfusion: therefore, closed clinical and radiologic
assessment of the whole thoraco-abdominal aorta is of utmost importance.
Long-term results are satisfying; unlimited radiographic follow-up allows
for detection of potential severe complications and for proper planning of
elective reoperations when indicated.
