Bicuspid aortic valve disease and pulmonary autograft root dilatation after the Ross procedure: A clinicopathologic study

Objective: Bicuspid aortic valve disease has been associated with histologi c abnormalities of the aortic root. Recent reports have suggested similar a lterations may exist in the pulmonary artery of patients with bicuspid aort ic valve. The present study was undertaken to define the histologic conditi on of the aortic and pulmonary artery root in bicuspid aortic valve disease and the relationship with pulmonary autograft root dilatation after the Ro ss procedure. Methods: In 17 patients undergoing aortic root replacement with the pulmona ry autograft, biopsy specimens of the aortic root and pulmonary artery trun k were collected, Clinical and histologic findings of patients with bicuspi d aortic valves were compared with those with tricuspid aortic valves. Results: There were 9 patients (8 male, 1 female) with bicuspid aortic valv e (group 1) and 8 (all male) with tricuspid aortic valve (group 2). Mean ag e was comparable (24.4 +/- 9.8 vs 23.6 +/- 10.8 years, P = .9). Aortic insu fficiency as an indication for operation was more common in group 1 (9/9 vs 5/8, P = .007), whereas preoperative aortic root dilatation was equally pr evalent (4/9 vs 1/8, P = .1). Prior aortic valve repair had been performed in 2 patients (1/9 vs 1/8, P = .9). Prevalence of cys tic medionecrosis of the aortic wall was similar in the 2 groups (4/9 vs 3/8, P = .6). Cystic me dionecrosis of the pulmonary artery trunk was found only in I patient with tricuspid aortic valve (0/9 vs 1/8, P = .3). During a mean follow-up of 26. 5 +/- 12.2 months (32.1 +/- 12.7 vs 20.1 +/- 7.4 months, P = .04), prevalen ce of pulmonary autograft root dilatation (greater than 4.0 cm) was equally represented in patients with native bicuspid or tricuspid aortic valve (3/ 9 vs 2/8, P = .6). Conclusions: Histologic abnormalities of the pulmonary artery root are rare and equally prevalent in young patients with bicuspid and tricuspid aortic valves. On the contrary, root dilatation is relatively common late after a utograft root replacement but appears unrelated to bicuspid aortic valve di sease or to pre-existing degenerative changes of the pulmonary artery root.