Aortic root geometry and stentless porcine valve competence.
Jin XY., Westaby S.
The goal of this study was to characterize medium-term changes in aortic root geometry after stentless aortic valve replacement, the relationship between aortic sinotubular junction and the competence of stentless valves. A total of 205 consecutive patients (mean age 73+/-6 years; 120 men, 85 women) received a Freestyle stentless porcine aortic valve and were studied prospectively by echocardiography from 1 week to 5 years. Internal diameters of outflow tract, annulus, sinus, sinotubular junction, and ascending aortic root were measured at early ejection and indexed to stentless valve size. The degree of stentless valve regurgitation was semiquantified by color Doppler echocardiography. A total of 701 echocardiographic studies were obtained and analyzed; 73% showed a fully competent stentless valve (nAR) and 13% and 14%, respectively, showed a trivial (tAR) or mild (mAR) regurgitation. Sinotubular junction of tAR or mAR was significantly greater than that of nAR (111+/-1.9, 117+/-2.2 vs. 104+/-1.0, percentage of valve size, P<.001). A preoperative diagnosis of aortic regurgitation (110+/-2.6 vs. 104+/-1.0, percentage of valve size, P<.001) and 4 to 5-year follow-up time (116+/-2.2 vs. 107+/-2.9, percentage of valve size, P = .023) were associated with a greater sinotubular junction, although the incidence and mean grade of stentless valve regurgitation did not change significantly during the follow-up period. Up to medium-term follow-up evaluation, the incidence of moderate stentless aortic regurgitation is less than 5%. The nature of valve disease and age-related increase in sinotubular junction may have reduced the cusp coaptation area of the stentless valve and may predict the presence of a trivial or mild regurgitation. Understanding the interrelations between the stentless valve and remodeling of the aging aorta has important implications for both surgical technique and long-term follow-up outcome.