The fate of mild-to-moderate proximal aortic dilatation after isolated aortic valve replacement for bicuspid aortic valve stenosis: a magnetic resonance imaging follow-up study†

OBJECTIVES: The treatment of mild-to-moderate aortic dilatation at the time of aortic valve replacement (AVR) in patients with bicuspid aortic valve (BAV) disease is still controversial. We aimed to estimate late progression of aortopathy in patients who underwent isolated AVR for BAV stenosis with concomitant proximal aortic dilatation of ≥40 mm.

METHODS: The review of our institutional BAV database (n = 510) revealed a subgroup of 96 consecutive BAV patients (57 ± 10 years, 78% male) with BAV stenosis and concomitant ascending aortic dilatation of ≥40 mm [i.e. as defined by magnetic resonance imaging (MRI)/computed tomography (CT)], who underwent isolated AVR from 1995 to 2006. Aortic diameters were quantified by preoperative MRI/CT in all patients (i.e. all cases without MRI/CT were excluded). Moreover, we excluded all cases of simultaneous aortic surgery. MRI/CT follow-up (855 patient-years) was obtained in 83 (87%) patients. Study end-points were progression of proximal aortic diameters (mm/patient-year) and prevalence of aortic events (sudden death, aortic dissection and aortic surgery).

RESULTS: MRI/CT follow-up (mean 10.3 ± 3.8 years post-AVR) revealed no significant progress of maximal cross-sectional aortic diameters (i.e. 46.4 ± 4.4 mm pre-AVR vs 46.9 ± 4.6 mm post-AVR, P = 0.1). Aortic diameters were identical in 54 (65%) patients. The mean progression rate of maximal cross-sectional aortic diameter was 0.09 mm/patient-year for the whole study cohort, whereas diameter increase of ≥5 mm was revealed in 1 (1%) patient. No aortic dissection occurred. Five (5%) patients underwent redo aortic surgery for aneurysm, whereas 3 of them had aortic diameters identical to pre-AVR.

CONCLUSIONS: Mild-to-moderate ascending aortic dilatation remains stable in most BAV patients who underwent isolated AVR surgery for aortic valve stenosis at least 10-year post-AVR.