Aortic valve replacement for aortic stenosis in the elderly: influence of prosthesis-patient mismatch on late survival and left ventricular mass regression

Purpose Controversy still exists about the influence of prosthesis-patient mismatch on outcomes after aortic valve replacement in the elderly. Our aim was to evaluate the effect of prosthesis-patient mismatch on survival and the extent of left ventricular (LV) mass regression after aortic valve replacement for aortic stenosis in Japanese patients aged ≥65 years. Materials and methods A total of 84 patients who underwent isolated aortic valve replacement for aortic stenosis between 1986 and 2006 were retrospectively analyzed. Patients were divided into two groups based on the definition of prosthesis-patient mismatch (indexed effective orifice area ≤0.85 cm 2 /m 2 ), and long-term results were compared. The mean follow-up time was 4.5 ± 4.5 years. In 49 patients, follow-up echocardiography was performed at least 6 months after surgery, and the extent of LV mass regression was analyzed according to the presence of a prosthesis-patient mismatch. Results Eight years after surgery, there was no significant difference between patients with and without mismatch in terms of actuarial freedom from cardiac-related death ( P = 0.159) or death from any valve-related events ( P = 0.107). The postoperative transvalvular pressure gradients were not significantly different between the two groups, and significant absolute and relative LV mass regression were observed in both groups. Conclusion Although a moderate prosthesis-patient mismatch appeared to be tolerable, the criteria of prosthesis-patient mismatch may have to be reassessed for elderly Japanese patients.