Effects of ascending aorta replacement on aortic root dilatation.

OBJECTIVE: Because of an increase of aortic root wall stress, prosthetic replacement of the ascending aorta might be a risk factor for the progressive increase of the aortic root dimension. Aim of the present study was to evaluate the aortic root diameter change and the progression of aortic valve regurgitation late after ascending aorta replacement for different ethiology. METHODS: Sixty-three late survivors after supracoronary ascending aortic replacement were evaluated. Forty-one patients were operated on for acute aortic dissecting aneurysm (group I) and 22 for chronic atherosclerotic non-dissecting aneurysm (group II). Aortic root diameter and aortic valve regurgitation were assessed echocardiografically after a mean follow-up of 63+/-31 months and were compared with those early after surgery. RESULTS: Seven patients of group I (17%) needed reoperation for aortic root dilatation or dissection. Twenty-five percent of the patients (15 of group I and 1 of group II) showed at least a 10% increase in aortic root diameter at follow-up (46.8+/-6.1 vs. 38.1+/-6.1mm, P<0.0001). Aortic root diameter increased almost exclusively in patients operated on for acute dissecting aneurysm. A significant worsening of aortic valve insufficiency with time was evident only in patients operated on for acute dissecting aneurysm with an higher incidence in those with progressive root dilatation. CONCLUSIONS: Both the increase of aortic root diameter and the progressive worsening of aortic valve insufficiency seem to justify a more aggressive treatment of the aortic root at the time of surgery for acute aortic dissecting aneurysm but not for chronic atherosclerotic non-dissecting aneurysms.