LONG-TERM OUTCOME OF THE FALSE LUMEN AFTE R SURGERY OF ACUTE TYPE-A DISSECTION OF THE AORTA

The long-term outcome (64.3 +/- 45 months) of 44 patients operated for acute dissection of at least the ascending aorta was assessed by regu lar clinical examination and annual CT scan. The diameter of the aorta at different levels was measured at each CT scan for all patients. in itially 7 patients (16 %) had acute dissection limited to the ascendin g aorta; none had a false lumen after surgery. No signs of aneurysmal dilatation were observed during follow-up of these patients. In the 37 other cases (84 %) dissection of the aorta extended beyond the innomi nate artery; the false lumen remained patent distal to the prosthetic tube replacing the ascending aorta in 34 patients (92 %). The false lu men was partially thrombosed in 8 % of patients, leading to distal emb oli in 1 patient. Moderate increases (less than 15 mm) in diameter of the false lumen were observed in 32 % of patients; more severe dilatat ion (over 20 mm) was observed in 12 % of patients. The management of d ilatation of the false lumen is not standard; it depends mainly on the rate of progression and the clinical consequences. It is hoped that e xtension of the initial repair to the aortic arch, when the intimal te ar is situated in this zone, will reduce the short and longterm progre ssion of the false lumen.